单选题In some cases the organisms that cause blood poisoning enter the bloodstream through contaminated needles or other improperly sterilized instruments.A contactedB infectedC contagiousD infectious

考题 HIV can be transmitted through () A、direct contact of a musous or the bloodstream with a body fluid containing HIVB、sexual intercourse, drug abuse, and blood transfusionC、pregnancy, child birth or breast feedingD、sharing hot pot with AIDS patients

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考题 Which of the following statement is true? () A、Hepatitis A often leads to chronic liver disease.B、Hepatitis B can be infected by sharing toothbrushes.C、With the improvement of medical technology, the risk of catchinghepatitis from contaminated blood products and blood transfusions has decreased.D、The symptoms of the hepatitis A, B and C are quite different from each other.

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考题 CFood sometimes gets poisoned with harmful things. A person who eats such food can get an illness called food poisoning. Food poisoning is usually not serious, but some types are deadly. The symptoms of food poisoning usually begin within hours of eating the poisoned food. Fever is one of the most common symptoms.Certain microorganisms（微生物）cause most types of food poisoning. Bacteria and other microorganisms can poison eggs, meat, vegetables, and many other foods. After entering the body, these tiny living things release（释放）poisons that make people sick.Some chemicals can also cause food poisoning. They are often added to food while it is being grown, processed, or prepared. For example, many farmers spray chemicals on crops to kill weeds and insects. Some people may have a bad reaction to those chemicals when they eat the crops.Some plants and animals contain natural poisons that are harmful to people. These include certain kinds of seafood, grains, nuts, seeds, beans, and mushrooms.When people handle food properly, the risk of food poisoning is very small. Microorganisms multiply rapidly in dirty places and in warm temperatures. This means that people should never touch food with dirty hands or put food on unwashed surfaces. Food should be kept in a refrigerator to stop microorganisms from growing. Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food covered with chemicals before eating it. Finally, people should not eat wild mushrooms or other foods that grow in the wild. Some of these foods may contain natural materials that are poisonous to humans. In addition, some types of fish can be poisonous.Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat natural poisons, they must go to the hospital right away to have their stomachs emptied.51. Which of the following statements is NOT true?A. Food when poisoned can make people sick.B. Food poisoning means death.C. Food poisoning comes in varieties.D. Food poisoning can be serious.

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考题 Ventilation ().A、is a system for moving fresh airB、can cut indoor pollution to a safe levelC、can cause some diseasesD、is better done through air-conditioning

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考题 When the author mentions the Indian fakir, he suggests that______.A) Indians are not at all afraid of painB) people may be senseless of painC) some people are able to handle painD) fakirs have magic to put needles right through their arms

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考题 In some cases, when a predator approaches, fishes escape on hearing ______.A. the sounds of other speciesB. the sounds of their preyC. the sounds of the approaching enemyD. the sounds of their fellows

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考题 What is NOT a problem when carrying coal ________．A.The requirement for through-ventilationB.The corrosion some types of coal will cause to the shipC.Spontaneous heatingD.Generation of methane gas

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考题共用题干 Surgery Involving the Heart1 The heart-lung machine(pump-oxygenator)is a valuable addition to the modern operating room. This machine has made it possible to perform many operations on the heart and other thoracic organs which could not otherwise be done.There are several types of machines in use,all of which serve as a temporary substitute for the patient's heart and lungs.2 The machine siphons off the blood from the large vessels entering the heart on the right side so that no blood passes through the heart and lungs.The blood is returned to the general circulation for body distribution through one of the large arteries.While passing through the machine,the blood is oxygenated by means of an oxygen inlet,and carbon dioxide is removed by various chemical means.These are the processes that normally take place between the blood and the air in the lung tissue.While in the machine,the blood is also deformed to be sure that all air bubbles are removed,since such bubbles could be fatal to the patient byobstructing blood vessels.An electric motor in the machine serves as a pump during the surgical procedure to distribute the processed blood throughout the body by means of the artery mentioned above.3 Diseased valves may become deformed and scarred from endocarditis so that they are ineffective and often obstructive.In some cases a special small knife can be inserted into the heart chamber and the valve can be cut so that it no longer obstructs the blood flow. The valve may even become partially functional.In other cases there may be so much damage that replacement is the only resort. Substitute valves,made of plastic materials have proved to be a lifesaving measure for many patients.Very thin butterfly valves made of dacron（涤纶）or other synthetic material have also been successfully used.4 Artificial hearts or parts of hearts designed to assist the ventricles in their pumping function have not proved as successful as the artificial valves.However,research continues and it is quite possible that an effective device may soon be ready for use.More spectacular is the transplantation of a human heart from the body of a person who has recently died.Tissues of the donor and the recipient should be as closely matched as possible to avoid rejection by the recipient's antibody mechanism.This rejection syndrome is the most serious problem related to heart transplants.The heart-lung machine is an essential helper for surgeons________.A:and finally they fail to function properlyB:to perform many surgical operations on the chestC:when it passes through the heart-lung machineD:and they no longer obstruct the blood flowE:to match tissues of the donor and the recipientF: when the ineffective valves are replaced by artificial ones

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考题共用题干 LeukemiaLeukemia is the most common type of cancer kids get,but it is still very rare.Leukemia involves the blood and blood-forming organs,such as the bone marrow.________(46)A kid with leukemia produces lots of abnormal white blood cells in the bone marrow. Usually,white blood cells fight infection,but the white blood cells in a person with leukemia don't work the way they're supposed to.________(47)The abnormal white blood cells multiply out of control,filling the bone marrow and making it hard for enough normal,infection-fighting white blood cells to form.Other blood cells一such asred blood cells(that carry oxygen in the blood to the body's tissues)and platelets(that allow blood to clot）一are also crowded out by the white blood cells of leukemia. These cancer cells may also move to other parts of the body,including the bloodstream,where they continue to multiply and build up.Although leukemia can make kids sick,most of the time it is treatable,and kids get better. Almost all leukemia patients are treated with chemotherapy,which means using anti-cancer drug.________(48)Chemotherapy quickly goes to work,traveling through the blood to the bone marrow. There,the drugs can attack the cancer cells.After several weeks of chemotherapy,many kids begin to feel better.Some children with leukemia will also have to have radiation therapy,too.________(49)If the cancer isn't getting better from using the usual amounts of chemotherapy and radiation,then a kid with leukemia will probably need more treatment一with higher doses of chemotherapy and radiation to finally kill the cancer cells.But this heavy-duty treatment will also harm the normal cells in the kid's bone marrow too,and the bone marrow will no longer be able to produce normal blood cells.So,doctors will then give a kid一or anyone else with bone marrow that is no longer working一normal bone marrow tissue from someone else who is healthy.________(50)___________（50）A:The chemotherapy drugs are given through a catheter,a narrow tube that is inserted into a blood vessel, sometimes in the kid's upper chest.B:Early symptoms of leukemia are often overlooked,since they may resemble symptoms of the flu or other common diseases.C:This is a special procedure called a bone marrow transplant,and it helps the patient make new blood cells so they can recover from the leukemia.D:Bone marrow is the innermost part of some bones where blood cells are first made.E:They don't protect the person from infections very well.F: Radiation therapy uses invisible high-energy waves(similar to X-rays)to kill cancerous cells.

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考题共用题干 Surgery Involving the Heart1 The heart-lung machine(pump-oxygenator)is a valuable addition to the modern operating room. This machine has made it possible to perform many operations on the heart and other thoracic organs which could not otherwise be done.There are several types of machines in use,all of which serve as a temporary substitute for the patient's heart and lungs.2 The machine siphons off the blood from the large vessels entering the heart on the right side so that no blood passes through the heart and lungs.The blood is returned to the general circulation for body distribution through one of the large arteries.While passing through the machine,the blood is oxygenated by means of an oxygen inlet,and carbon dioxide is removed by various chemical means.These are the processes that normally take place between the blood and the air in the lung tissue.While in the machine,the blood is also deformed to be sure that all air bubbles are removed,since such bubbles could be fatal to the patient byobstructing blood vessels.An electric motor in the machine serves as a pump during the surgical procedure to distribute the processed blood throughout the body by means of the artery mentioned above.3 Diseased valves may become deformed and scarred from endocarditis so that they are ineffective and often obstructive.In some cases a special small knife can be inserted into the heart chamber and the valve can be cut so that it no longer obstructs the blood flow. The valve may even become partially functional.In other cases there may be so much damage that replacement is the only resort. Substitute valves,made of plastic materials have proved to be a lifesaving measure for many patients.Very thin butterfly valves made of dacron（涤纶）or other synthetic material have also been successfully used.4 Artificial hearts or parts of hearts designed to assist the ventricles in their pumping function have not proved as successful as the artificial valves.However,research continues and it is quite possible that an effective device may soon be ready for use.More spectacular is the transplantation of a human heart from the body of a person who has recently died.Tissues of the donor and the recipient should be as closely matched as possible to avoid rejection by the recipient's antibody mechanism.This rejection syndrome is the most serious problem related to heart transplants.Paragraph 3________ A:The Heart TransplantationB:How the Heart-lung Machine WorksC:A Machine Making Many Kinds of Thoracic Operations PossibleD:A Temporary Substitute for the Diseased ValveE:Operations on Cardiac Valves and Substitutes for ValvesF: How Every Part of the Heart Performs Its Function

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考题共用题干 Surgery Involving the Heart1 The heart-lung machine(pump-oxygenator)is a valuable addition to the modern operating room. This machine has made it possible to perform many operations on the heart and other thoracic organs which could not otherwise be done.There are several types of machines in use,all of which serve as a temporary substitute for the patient's heart and lungs.2 The machine siphons off the blood from the large vessels entering the heart on the right side so that no blood passes through the heart and lungs.The blood is returned to the general circulation for body distribution through one of the large arteries.While passing through the machine,the blood is oxygenated by means of an oxygen inlet,and carbon dioxide is removed by various chemical means.These are the processes that normally take place between the blood and the air in the lung tissue.While in the machine,the blood is also deformed to be sure that all air bubbles are removed,since such bubbles could be fatal to the patient byobstructing blood vessels.An electric motor in the machine serves as a pump during the surgical procedure to distribute the processed blood throughout the body by means of the artery mentioned above.3 Diseased valves may become deformed and scarred from endocarditis so that they are ineffective and often obstructive.In some cases a special small knife can be inserted into the heart chamber and the valve can be cut so that it no longer obstructs the blood flow. The valve may even become partially functional.In other cases there may be so much damage that replacement is the only resort. Substitute valves,made of plastic materials have proved to be a lifesaving measure for many patients.Very thin butterfly valves made of dacron（涤纶）or other synthetic material have also been successfully used.4 Artificial hearts or parts of hearts designed to assist the ventricles in their pumping function have not proved as successful as the artificial valves.However,research continues and it is quite possible that an effective device may soon be ready for use.More spectacular is the transplantation of a human heart from the body of a person who has recently died.Tissues of the donor and the recipient should be as closely matched as possible to avoid rejection by the recipient's antibody mechanism.This rejection syndrome is the most serious problem related to heart transplants.Endocarditis may cause valves to be damaged________.A:and finally they fail to function properlyB:to perform many surgical operations on the chestC:when it passes through the heart-lung machineD:and they no longer obstruct the blood flowE:to match tissues of the donor and the recipientF: when the ineffective valves are replaced by artificial ones

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考题共用题干 Surgery Involving the Heart1 The heart-lung machine(pump-oxygenator)is a valuable addition to the modern operating room. This machine has made it possible to perform many operations on the heart and other thoracic organs which could not otherwise be done.There are several types of machines in use,all of which serve as a temporary substitute for the patient's heart and lungs.2 The machine siphons off the blood from the large vessels entering the heart on the right side so that no blood passes through the heart and lungs.The blood is returned to the general circulation for body distribution through one of the large arteries.While passing through the machine,the blood is oxygenated by means of an oxygen inlet,and carbon dioxide is removed by various chemical means.These are the processes that normally take place between the blood and the air in the lung tissue.While in the machine,the blood is also deformed to be sure that all air bubbles are removed,since such bubbles could be fatal to the patient byobstructing blood vessels.An electric motor in the machine serves as a pump during the surgical procedure to distribute the processed blood throughout the body by means of the artery mentioned above.3 Diseased valves may become deformed and scarred from endocarditis so that they are ineffective and often obstructive.In some cases a special small knife can be inserted into the heart chamber and the valve can be cut so that it no longer obstructs the blood flow. The valve may even become partially functional.In other cases there may be so much damage that replacement is the only resort. Substitute valves,made of plastic materials have proved to be a lifesaving measure for many patients.Very thin butterfly valves made of dacron（涤纶）or other synthetic material have also been successfully used.4 Artificial hearts or parts of hearts designed to assist the ventricles in their pumping function have not proved as successful as the artificial valves.However,research continues and it is quite possible that an effective device may soon be ready for use.More spectacular is the transplantation of a human heart from the body of a person who has recently died.Tissues of the donor and the recipient should be as closely matched as possible to avoid rejection by the recipient's antibody mechanism.This rejection syndrome is the most serious problem related to heart transplants.The blood is oxygenated and carbon dioxide in it is removed________.A:and finally they fail to function properlyB:to perform many surgical operations on the chestC:when it passes through the heart-lung machineD:and they no longer obstruct the blood flowE:to match tissues of the donor and the recipientF: when the ineffective valves are replaced by artificial ones

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考题共用题干 Acupuncture一Old Chinese MedicineFor more than 4,000 years people in Asia have used acupuncture to treat illnesses.________ (46)Today acupuncture is also very popular in Europe,America and Australia.Acupuncture can control pain and sickness.It can also be used if you have a headache or back pain.Some doctors use acupuncture along with regular treatments for asthma,high blood pressure or stress.________(47)Some people think that acupuncture can treat depression and even help people to stop smoking. Many patients feel more energy after a treatment,while others may feel more relaxed.People who practice acupuncture must take courses to learn how to do it correctly._________(48)During treatment the patient lies down and needles are stuck into certain points of the body. There are hundreds of possible points and each one has a certain effect on the body._________(49) For example you stick a needle into the hand to treat problems with your stomach.Acupuncture needles are made of metal and about as thick as a human hair. They normally go less than one cm into the skin.When they are in the skin the acupuncturist may twist them or send electricity through them.The patients rest for a short time and then the needles are removed.Acupuncture normally doesn't hurt. There is also a milder form of acupuncture called acupressure where you don't need needles.Doctors use their fingers to press the points of the body.Chinese medicine teaches us that all acupuncture points are located along pathways called meridians.Each of these meridians carries energy,which the Chinese call "qi" to certain points of the body.If this "qi" gets blocked from an area the person will get sick or feel pain.Sticking needles into the correct points can help "qi" flow again and make the person well.Doctors today are not sure how acupuncture really works.They have not found any proof that these pathways of energy really exist.Some think that needles cause the body to produce pain killing substances.________(50)Some also say that acupuncture only works because patients believe in it._________（50）A:In many places,especially outside of Asia,only doctors are allowed to perform acupuncture.B:The earliest written record of acupuncture is found in the Huangdi Neijing.C:Doctors have even used acupuncture to stop pain during an operation.D:The points can also be very far away from the place of pain.E:Others think that the needles block pain signals that travel along the nerves to the brain.F: It is an old Chinese form of healing in which your skin is pierced with thin needles to relieve pain.

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考题共用题干 Geology and Health1. The importance of particular metals in the human diet has been realized within the past few decades,and the idea that geology might be related to health has been recognized for a number of elements such as iodine,zinc and selenium. For example,soils with low iodine contents produce crops,and animals deficient in iodine.A lack of iodine in the human diet leads to some serious diseases.2.The ultimate source of metals within the human body is rocks,which weather into soil.gaining or losing some of their chemical constituents. The crops we eat selectively remove from the soil the elements that they require for growth .The water we drink contains trace elements leached from rock and soil. Thus the geology and geochemistry of the environments have effects on the chemis-try and health of plants,animals and people.3. So far there is no data to suggest that people living on metal-rich soils experience a potential health hazard. The levels of metals within naturally contaminated soils are generally not high enough to cause serious health problems.Living on metal-rich soils does not represent a health risk unless large quantities of soil are digested or metal-rich dust is inhaled.However,small chil-dren are particularly exposed to metal-rich topsoil in playgrounds and gardens. They are also the most likely ones to eat potentially dangerous metal-rich soil.4. Heavy metals are persistent:they do not break down to other chemicals in the environment. Industrially polluted sites usually undergo intensive clean-up and rehabilitation because heavy metals are a health concern once they enter the food chain. Some trace metals are alleged to cause cancer and are also known to cause poisoning.5.In contrast,naturally contaminated soils have not been subject to risk assessment studies and rehabilitation measures,despite the fact that they frequently possess metal concentrations well above those of such polluted by humans and above environmental quality criteria.6.There is a vital need to understand the potential risks and long-term health effects of living on naturally contaminated soils.Future environmental investigations of naturally polluted soils should concentrate on the potential pathways of metals into the food chain and human body.Geologists should be part of such studies as they can provide the essential background information on rock and soil chemistry as well as the chemical forms of heavy metal pollution. Paragraph 1______A:.No evidence to indicate bad effects of naturally contaminated soilB:.Potential hazards of human contaminated soilsC: Research on channels of heavy metals getting into human food chainD: Geology and health problemsE:.Rocks-the ultimate source of soil pollutionF: Long-term health effects on children

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考题共用题干第一篇Food PoisoningFood sometimes gets poisoned with harmful things,A person who eats such food can get an illness called food poisoning. Food poisoning is usually not serious,but some types are deadly.The symptoms of food poi- soning usually begin within hours of eating the poisoned food.Fever is one of the most common symptoms.Certain microorganisms（微生物）cause most types of food poisoning. Bacteria and other microorganisms can poison eggs,meat,vegetables,and many other foods.After entering the body,these tiny living things re- lease（释放）poisons that make people sick.Some chemicals can also cause food poisoning. They are often added to food while it is being grown,pro- cessed,or prepared.For example,many farmers spray chemicals on crops to kill weeds and insects.Some people may have a bad reaction to those chemical、when they eat the crops.Some plants and animals contain natural poisons that are harmful to people.These includo certain kinds of seafood,grains,nuts,seeds,beans,and mushrooms.When people handle food properly,the risk of food poisoning is very small.Microorganisms multiply rapidly in dirty places and in warm temperatures.This means that people should never touch food with dirty hands or put food on unwashed surfaces.Food should be kept in a refrigerator to stop microorganisms from growing, Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food covered with chemicals before eating it.Finally,people should not eat wild mushrooms or other foods that grow in the wild.Some of these foods may contain natural materials that are poisonous to humans.In addition,some types of fish can be poisonous.Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat natural poisons,they must go to the hospital right away to have their stomachs emptied. From Paragraph 5,we can learn that_______________.A:mushrooms should not he eatenB:vegetables are safer than meat and seafoodC:natural poisons are more dangerous than chemicalsD:different types of food should he handled differently

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考题共用题干第一篇Food PoisoningFood sometimes gets poisoned with harmful things,A person who eats such food can get an illness called food poisoning. Food poisoning is usually not serious,but some types are deadly.The symptoms of food poi- soning usually begin within hours of eating the poisoned food.Fever is one of the most common symptoms.Certain microorganisms（微生物）cause most types of food poisoning. Bacteria and other microorganisms can poison eggs,meat,vegetables,and many other foods.After entering the body,these tiny living things re- lease（释放）poisons that make people sick.Some chemicals can also cause food poisoning. They are often added to food while it is being grown,pro- cessed,or prepared.For example,many farmers spray chemicals on crops to kill weeds and insects.Some people may have a bad reaction to those chemical、when they eat the crops.Some plants and animals contain natural poisons that are harmful to people.These includo certain kinds of seafood,grains,nuts,seeds,beans,and mushrooms.When people handle food properly,the risk of food poisoning is very small.Microorganisms multiply rapidly in dirty places and in warm temperatures.This means that people should never touch food with dirty hands or put food on unwashed surfaces.Food should be kept in a refrigerator to stop microorganisms from growing, Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food covered with chemicals before eating it.Finally,people should not eat wild mushrooms or other foods that grow in the wild.Some of these foods may contain natural materials that are poisonous to humans.In addition,some types of fish can be poisonous.Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat natural poisons,they must go to the hospital right away to have their stomachs emptied. It can be inferred from the passage that_______________.A:natural materials are safe in food processingB:chemicals are needed in food processing C:food poisoning can be kept under control D:food poisoning is out of control

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考题共用题干 Geology and Health1. The importance of particular metals in the human diet has been realized within the past few decades,and the idea that geology might be related to health has been recognized for a number of elements such as iodine,zinc and selenium. For example,soils with low iodine contents produce crops,and animals deficient in iodine.A lack of iodine in the human diet leads to some serious diseases.2.The ultimate source of metals within the human body is rocks,which weather into soil.gaining or losing some of their chemical constituents. The crops we eat selectively remove from the soil the elements that they require for growth .The water we drink contains trace elements leached from rock and soil. Thus the geology and geochemistry of the environments have effects on the chemis-try and health of plants,animals and people.3. So far there is no data to suggest that people living on metal-rich soils experience a potential health hazard. The levels of metals within naturally contaminated soils are generally not high enough to cause serious health problems.Living on metal-rich soils does not represent a health risk unless large quantities of soil are digested or metal-rich dust is inhaled.However,small chil-dren are particularly exposed to metal-rich topsoil in playgrounds and gardens. They are also the most likely ones to eat potentially dangerous metal-rich soil.4. Heavy metals are persistent:they do not break down to other chemicals in the environment. Industrially polluted sites usually undergo intensive clean-up and rehabilitation because heavy metals are a health concern once they enter the food chain. Some trace metals are alleged to cause cancer and are also known to cause poisoning.5.In contrast,naturally contaminated soils have not been subject to risk assessment studies and rehabilitation measures,despite the fact that they frequently possess metal concentrations well above those of such polluted by humans and above environmental quality criteria.6.There is a vital need to understand the potential risks and long-term health effects of living on naturally contaminated soils.Future environmental investigations of naturally polluted soils should concentrate on the potential pathways of metals into the food chain and human body.Geologists should be part of such studies as they can provide the essential background information on rock and soil chemistry as well as the chemical forms of heavy metal pollution.Industrially contaminated sites usually require a thorough clean-up due to______＿.A:.industrially polluted soilsB: rock and soil chemistryC:.naturally polluted soilsD: the pathways of metals into the food chainE: the element of iodineF: the persistence of heavy metals

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考题共用题干第一篇Food PoisoningFood sometimes gets poisoned with harmful things,A person who eats such food can get an illness called food poisoning. Food poisoning is usually not serious,but some types are deadly.The symptoms of food poi- soning usually begin within hours of eating the poisoned food.Fever is one of the most common symptoms.Certain microorganisms（微生物）cause most types of food poisoning. Bacteria and other microorganisms can poison eggs,meat,vegetables,and many other foods.After entering the body,these tiny living things re- lease（释放）poisons that make people sick.Some chemicals can also cause food poisoning. They are often added to food while it is being grown,pro- cessed,or prepared.For example,many farmers spray chemicals on crops to kill weeds and insects.Some people may have a bad reaction to those chemical、when they eat the crops.Some plants and animals contain natural poisons that are harmful to people.These includo certain kinds of seafood,grains,nuts,seeds,beans,and mushrooms.When people handle food properly,the risk of food poisoning is very small.Microorganisms multiply rapidly in dirty places and in warm temperatures.This means that people should never touch food with dirty hands or put food on unwashed surfaces.Food should be kept in a refrigerator to stop microorganisms from growing, Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food covered with chemicals before eating it.Finally,people should not eat wild mushrooms or other foods that grow in the wild.Some of these foods may contain natural materials that are poisonous to humans.In addition,some types of fish can be poisonous.Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat natural poisons,they must go to the hospital right away to have their stomachs emptied. Which of the following statements is NOT true?A:Food when poisoned can make people sick.B:Food poisoning means death.C:F0od poisoning comes in varieties.D:Food poisoning can be serious,

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考题共用题干 Geology and Health1. The importance of particular metals in the human diet has been realized within the past few decades,and the idea that geology might be related to health has been recognized for a number of elements such as iodine,zinc and selenium. For example,soils with low iodine contents produce crops,and animals deficient in iodine.A lack of iodine in the human diet leads to some serious diseases.2.The ultimate source of metals within the human body is rocks,which weather into soil.gaining or losing some of their chemical constituents. The crops we eat selectively remove from the soil the elements that they require for growth .The water we drink contains trace elements leached from rock and soil. Thus the geology and geochemistry of the environments have effects on the chemis-try and health of plants,animals and people.3. So far there is no data to suggest that people living on metal-rich soils experience a potential health hazard. The levels of metals within naturally contaminated soils are generally not high enough to cause serious health problems.Living on metal-rich soils does not represent a health risk unless large quantities of soil are digested or metal-rich dust is inhaled.However,small chil-dren are particularly exposed to metal-rich topsoil in playgrounds and gardens. They are also the most likely ones to eat potentially dangerous metal-rich soil.4. Heavy metals are persistent:they do not break down to other chemicals in the environment. Industrially polluted sites usually undergo intensive clean-up and rehabilitation because heavy metals are a health concern once they enter the food chain. Some trace metals are alleged to cause cancer and are also known to cause poisoning.5.In contrast,naturally contaminated soils have not been subject to risk assessment studies and rehabilitation measures,despite the fact that they frequently possess metal concentrations well above those of such polluted by humans and above environmental quality criteria.6.There is a vital need to understand the potential risks and long-term health effects of living on naturally contaminated soils.Future environmental investigations of naturally polluted soils should concentrate on the potential pathways of metals into the food chain and human body.Geologists should be part of such studies as they can provide the essential background information on rock and soil chemistry as well as the chemical forms of heavy metal pollution.Some diseases is connected with deficiency of_______.A:.industrially polluted soilsB: rock and soil chemistryC:.naturally polluted soilsD: the pathways of metals into the food chainE: the element of iodineF: the persistence of heavy metals

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考题共用题干第一篇Food PoisoningFood sometimes gets poisoned with harmful things,A person who eats such food can get an illness called food poisoning. Food poisoning is usually not serious,but some types are deadly.The symptoms of food poi- soning usually begin within hours of eating the poisoned food.Fever is one of the most common symptoms.Certain microorganisms（微生物）cause most types of food poisoning. Bacteria and other microorganisms can poison eggs,meat,vegetables,and many other foods.After entering the body,these tiny living things re- lease（释放）poisons that make people sick.Some chemicals can also cause food poisoning. They are often added to food while it is being grown,pro- cessed,or prepared.For example,many farmers spray chemicals on crops to kill weeds and insects.Some people may have a bad reaction to those chemical、when they eat the crops.Some plants and animals contain natural poisons that are harmful to people.These includo certain kinds of seafood,grains,nuts,seeds,beans,and mushrooms.When people handle food properly,the risk of food poisoning is very small.Microorganisms multiply rapidly in dirty places and in warm temperatures.This means that people should never touch food with dirty hands or put food on unwashed surfaces.Food should be kept in a refrigerator to stop microorganisms from growing, Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food covered with chemicals before eating it.Finally,people should not eat wild mushrooms or other foods that grow in the wild.Some of these foods may contain natural materials that are poisonous to humans.In addition,some types of fish can be poisonous.Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat natural poisons,they must go to the hospital right away to have their stomachs emptied. A:are always accompanied by a fever B:are too common to be notedC:can be noticed within hoursD:can he ignored

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考题共用题干第一篇Food PoisoningFood sometimes gets poisoned with harmful things,A person who eats such food can get an illness called food poisoning. Food poisoning is usually not serious,but some types are deadly.The symptoms of food poi- soning usually begin within hours of eating the poisoned food.Fever is one of the most common symptoms.Certain microorganisms（微生物）cause most types of food poisoning. Bacteria and other microorganisms can poison eggs,meat,vegetables,and many other foods.After entering the body,these tiny living things re- lease（释放）poisons that make people sick.Some chemicals can also cause food poisoning. They are often added to food while it is being grown,pro- cessed,or prepared.For example,many farmers spray chemicals on crops to kill weeds and insects.Some people may have a bad reaction to those chemical、when they eat the crops.Some plants and animals contain natural poisons that are harmful to people.These includo certain kinds of seafood,grains,nuts,seeds,beans,and mushrooms.When people handle food properly,the risk of food poisoning is very small.Microorganisms multiply rapidly in dirty places and in warm temperatures.This means that people should never touch food with dirty hands or put food on unwashed surfaces.Food should be kept in a refrigerator to stop microorganisms from growing, Meat needs to be cooked thoroughly to kill any dangerous microorganisms. People should also wash food covered with chemicals before eating it.Finally,people should not eat wild mushrooms or other foods that grow in the wild.Some of these foods may contain natural materials that are poisonous to humans.In addition,some types of fish can be poisonous.Most people recover from food poisoning after a few days of resting and drinking extra water. If people eat natural poisons,they must go to the hospital right away to have their stomachs emptied. Food poisoning can be caused by all of the following EXCEPT_______________.A:some chemicalsB:low temperaturesC:some tiny living thingsD:certain natural materials

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考题单选题Which of the following sentences explains the primary goal of hormone replacement therapy?A The quantities and proportions of hormones produce change with age, so scientists have given a great deal of study to shifts in the endocrine system over time in the hopes of alleviating ailments associated with aging.B A combination of estrogen and progesterone has been prescribed for decades to women who want to reduce mood swings, sudden changes in body temperature, and other discomforts caused by lower natural levels of those hormones as they enter middle age.C HRT may also increase the likelihood that blood clots—dangerous because they could travel through the bloodstream and block major blood vessels—will form.D Because of the complicated effects growth hormone has on the body, such treatments are generally restricted to children who would be pathologically small in stature without it.

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考题单选题Which of the following problems could cause air to blow out through the inlet air filter of a running compressor?（）A Excessive compression in the cylinderB A broken intake valveC A dirty inlet filter elementD An improperly adjusted discharge valve

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考题单选题What is NOT a problem when carrying coal? （）A The requirement for through-ventilationB The corrosion some types of coal will cause to the shipC Spontaneous heatingD Generation of methane gas

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考题单选题If a user attempts to go to a website and notices the URL has changed， which of the following attacks is MOST likely the cause？（）A DLL injectionB DDoS attackC DNS poisoningD ARP poisoning

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考题单选题Why should you wear a self-contained breathing apparatus before entering the engine room after the fixed CO2 system has been discharged to combat a major fire?（）A Because carbon dioxide dilutes the oxygen concentration in the atmosphere and may cause asphyxiationB Because carbon dioxide breaks down in a fire into carbon monoxide which may cause blood poisoning in the person breathing this gasC Because carbon dioxide is a colorless and odorless gas that becomes highly toxic in the presence of high temperatures and will quickly incapacitate a person exposed to this gasD This action is unnecessary as carbon dioxide is not poisonous nor toxic but is a relatively harmless gas

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考题单选题The development goals for a large marine engine are many often interact and in some cases even with each other（）A conflictB accordC harmonizeD struggle

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