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名词解释题
Fetal antigen
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下列关于前列腺特异性抗原(prostate－specific antigen,PSA)的说法,不正确的是()
A.血清PSA为组织特异性而非疾病特异性B.PSA升高对前列腺癌，特别是高分化癌有较高的诊断价值C.PSA检查应在前列腺的直肠指诊前1周D.PSA检测时应无急性前列腺炎、尿潴留E.PSA检查应在膀胱镜检查、导尿等操作后48小时
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第一篇Immune FunctionsThe immune system is equal in complexity to the combined intricacies of the brain and nervous system. The success of the immune system in defending the body relies on a dynamic regulatory communication net- work consisting of millions and millions of cells.Organized into sets and subsets,these cells pass information back and forth like clouds of bees flying around a hive（蜂巢）.The result is a sensitive system of checks and balances that produces an immune response that is prompt,appropriate,effective,and self-limiting.At the heart of the immune system is the ability to distinguish between self and nonself. When immune defenders encounter cells or organisms carrying foreign or nonself molecules,the immune troops move quicklyto eliminate the intruders（人侵者）.Virtually every body cell carries distinctive molecules that identify it as self. The body's immune defenses do not normally attack tissues that carry a self-marker. Rather,immune cells and other body cells coexist peaceably in a state known as self-tolerance.When a normally functioning immune system attacks a nonself molecule,the system has the ability to"remember"the specifics of the foreign body.Upon subsequent encounters with the same species of molecules,the immune system reacts accordingly. With the possible exception of antibodies（抗体）passed during lactation（授乳期）, this so called immune system memory is not inherited.Despite the occurrence of a virus in your family,your immune system must"learn"from experience with the many millions of distinctive nonseif molecules in the sea of microbes（微生物）in which we live. Learning entails producing the appropriate molecules and cells to match up with and counteract each nonseif invader.Any substance capable of triggering an immune response is called an antigen（抗原）.Antigens are not to be confused with illergens（过敏原）,which are most often harmless substances that provoke the immune system to set off the inappropriate and harmful response known as allergy.An antigen can be a virus,a bacte-rium,or even a portion or product of one of these organisms.Tissues or cells from another individual also act as antigens,because the immune system recognizes transplanted tissues as foreign,it rejects them.The body will even reject nourishing proteins unless they are first broken down by the digestive system into their primary,nonantigenic building blocks.An antigen announces its foreignness by means of intricate and charac- teristic shapes called epitopes（抗原表位）, which protrude（突出）from its surface. Most antigens , even the simplest microbes,carry several different kinds of epitopes on their surface;some may even carry several hundreds.Some epitopes will be more effective than others at stimulating an immune response.Only in abnormal situations does the immune system wrongly identify self as nonself and execute a misdirected immune attack.What is used to describe the communication network consisting of cells in the immune system?A:The immune system's memory.B:Immune troops sliminating intruders.C:Bees flying around a hive.D:A sea of microbes.
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第一篇Immune FunctionsThe immune system is equal in complexity to the combined intricacies of the brain and nervous system. The success of the immune system in defending the body relies on a dynamic regulatory communication net- work consisting of millions and millions of cells.Organized into sets and subsets,these cells pass information back and forth like clouds of bees flying around a hive（蜂巢）.The result is a sensitive system of checks and balances that produces an immune response that is prompt,appropriate,effective,and self-limiting.At the heart of the immune system is the ability to distinguish between self and nonself. When immune defenders encounter cells or organisms carrying foreign or nonself molecules,the immune troops move quicklyto eliminate the intruders（人侵者）.Virtually every body cell carries distinctive molecules that identify it as self. The body's immune defenses do not normally attack tissues that carry a self-marker. Rather,immune cells and other body cells coexist peaceably in a state known as self-tolerance.When a normally functioning immune system attacks a nonself molecule,the system has the ability to"remember"the specifics of the foreign body.Upon subsequent encounters with the same species of molecules,the immune system reacts accordingly. With the possible exception of antibodies（抗体）passed during lactation（授乳期）, this so called immune system memory is not inherited.Despite the occurrence of a virus in your family,your immune system must"learn"from experience with the many millions of distinctive nonseif molecules in the sea of microbes（微生物）in which we live. Learning entails producing the appropriate molecules and cells to match up with and counteract each nonseif invader.Any substance capable of triggering an immune response is called an antigen（抗原）.Antigens are not to be confused with illergens（过敏原）,which are most often harmless substances that provoke the immune system to set off the inappropriate and harmful response known as allergy.An antigen can be a virus,a bacte-rium,or even a portion or product of one of these organisms.Tissues or cells from another individual also act as antigens,because the immune system recognizes transplanted tissues as foreign,it rejects them.The body will even reject nourishing proteins unless they are first broken down by the digestive system into their primary,nonantigenic building blocks.An antigen announces its foreignness by means of intricate and charac- teristic shapes called epitopes（抗原表位）, which protrude（突出）from its surface. Most antigens , even the simplest microbes,carry several different kinds of epitopes on their surface;some may even carry several hundreds.Some epitopes will be more effective than others at stimulating an immune response.Only in abnormal situations does the immune system wrongly identify self as nonself and execute a misdirected immune attack.The immune cells and other cells in the body coexist peaceably in a state known as________.A:self-toleranceB:balanceC:harmonyD:tolerance
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第一篇Immune FunctionsThe immune system is equal in complexity to the combined intricacies of the brain and nervous system. The success of the immune system in defending the body relies on a dynamic regulatory communication net- work consisting of millions and millions of cells.Organized into sets and subsets,these cells pass information back and forth like clouds of bees flying around a hive（蜂巢）.The result is a sensitive system of checks and balances that produces an immune response that is prompt,appropriate,effective,and self-limiting.At the heart of the immune system is the ability to distinguish between self and nonself. When immune defenders encounter cells or organisms carrying foreign or nonself molecules,the immune troops move quicklyto eliminate the intruders（人侵者）.Virtually every body cell carries distinctive molecules that identify it as self. The body's immune defenses do not normally attack tissues that carry a self-marker. Rather,immune cells and other body cells coexist peaceably in a state known as self-tolerance.When a normally functioning immune system attacks a nonself molecule,the system has the ability to"remember"the specifics of the foreign body.Upon subsequent encounters with the same species of molecules,the immune system reacts accordingly. With the possible exception of antibodies（抗体）passed during lactation（授乳期）, this so called immune system memory is not inherited.Despite the occurrence of a virus in your family,your immune system must"learn"from experience with the many millions of distinctive nonseif molecules in the sea of microbes（微生物）in which we live. Learning entails producing the appropriate molecules and cells to match up with and counteract each nonseif invader.Any substance capable of triggering an immune response is called an antigen（抗原）.Antigens are not to be confused with illergens（过敏原）,which are most often harmless substances that provoke the immune system to set off the inappropriate and harmful response known as allergy.An antigen can be a virus,a bacte-rium,or even a portion or product of one of these organisms.Tissues or cells from another individual also act as antigens,because the immune system recognizes transplanted tissues as foreign,it rejects them.The body will even reject nourishing proteins unless they are first broken down by the digestive system into their primary,nonantigenic building blocks.An antigen announces its foreignness by means of intricate and charac- teristic shapes called epitopes（抗原表位）, which protrude（突出）from its surface. Most antigens , even the simplest microbes,carry several different kinds of epitopes on their surface;some may even carry several hundreds.Some epitopes will be more effective than others at stimulating an immune response.Only in abnormal situations does the immune system wrongly identify self as nonself and execute a misdirected immune attack.Which of the following best expresses the main idea of this passage?A:An antigen is any substance that triggers an immune response.B:One of the immune system's primary functions is the allergic response.C:The human body is an appropriate habitat for microbes.D:The basic function of the immune system is to distinguish between self and nonseif.
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第一篇Immune FunctionsThe immune system is equal in complexity to the combined intricacies of the brain and nervous system. The success of the immune system in defending the body relies on a dynamic regulatory communication net- work consisting of millions and millions of cells.Organized into sets and subsets,these cells pass information back and forth like clouds of bees flying around a hive（蜂巢）.The result is a sensitive system of checks and balances that produces an immune response that is prompt,appropriate,effective,and self-limiting.At the heart of the immune system is the ability to distinguish between self and nonself. When immune defenders encounter cells or organisms carrying foreign or nonself molecules,the immune troops move quicklyto eliminate the intruders（人侵者）.Virtually every body cell carries distinctive molecules that identify it as self. The body's immune defenses do not normally attack tissues that carry a self-marker. Rather,immune cells and other body cells coexist peaceably in a state known as self-tolerance.When a normally functioning immune system attacks a nonself molecule,the system has the ability to"remember"the specifics of the foreign body.Upon subsequent encounters with the same species of molecules,the immune system reacts accordingly. With the possible exception of antibodies（抗体）passed during lactation（授乳期）, this so called immune system memory is not inherited.Despite the occurrence of a virus in your family,your immune system must"learn"from experience with the many millions of distinctive nonseif molecules in the sea of microbes（微生物）in which we live. Learning entails producing the appropriate molecules and cells to match up with and counteract each nonseif invader.Any substance capable of triggering an immune response is called an antigen（抗原）.Antigens are not to be confused with illergens（过敏原）,which are most often harmless substances that provoke the immune system to set off the inappropriate and harmful response known as allergy.An antigen can be a virus,a bacte-rium,or even a portion or product of one of these organisms.Tissues or cells from another individual also act as antigens,because the immune system recognizes transplanted tissues as foreign,it rejects them.The body will even reject nourishing proteins unless they are first broken down by the digestive system into their primary,nonantigenic building blocks.An antigen announces its foreignness by means of intricate and charac- teristic shapes called epitopes（抗原表位）, which protrude（突出）from its surface. Most antigens , even the simplest microbes,carry several different kinds of epitopes on their surface;some may even carry several hundreds.Some epitopes will be more effective than others at stimulating an immune response.Only in abnormal situations does the immune system wrongly identify self as nonself and execute a misdirected immune attack.How do the immune cells recognize an antigen as"foreign"or"nonself"?A:Through an allergic response.B:Through blood type.C:Through characteristic shapes on the antigen surface.D:Through fine hairs protruding from the antigen surface.
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第二篇Bone Marrow TransplantationBone marrow is the spongy tissue inside some of your bones,such as your hip and thigh bones. It contains immature cells,called stem cells.The stem cells can develop into the red blood cells that carry oxygen through your body,the white blood cells that fight infections,and the platelets that help with blood clotting.If there is a problem with your bone marrow,a transplant can give you healthy new marrow. You could need a transplant because of a disease,such as bone marrow diseases or cancers like leukemia kemia or lymphoma.Or you might need one if a strong cancer treatment kills your healthy blood cells.People with cancer sometimes donate bone marrow before treatment to be transplanted later. But often the new marrow comes from a donor,either a close family member or someone unrelated.The healthy cells for a transplant can come from three sources:bone marrow;peripheral (circulating) blood that has an increased number of healthy blood-forming cells(also called peripheral blood stem cells or PBSC);umbilical cord blood that is collected after a baby is born.If you need an allogeneic transplant,your doctor will look for a marrow donor or cord blood unit that matches your HLA tissue type.HLA stands for human leukocyte antigen,a markei your immune system uses to recognize which cells belong in your body and which do not.Before your body can receive the healthy cells,the diseased cells must be destroyed.This is done using chemotherapy and sometimes radiation. The destruction of diseased cells is called a preparative regimen or a conditioning regimen.On the day of transplant,the cells from the marrow donor or cord blood unit are infused intravenously(go into your body through a large vein).These healthy cells move into the spaces inside your bones where they create new marrow. They grow and make healthy new red blood cells,white blood cells,and platelets.Before receiving healthy cells,diseased cells must_________.A:undergo chemotherapyB:go through radiationC:be preparedD:be wrecked
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第二篇Bone Marrow TransplantationBone marrow is the spongy tissue inside some of your bones,such as your hip and thigh bones. It contains immature cells,called stem cells.The stem cells can develop into the red blood cells that carry oxygen through your body,the white blood cells that fight infections,and the platelets that help with blood clotting.If there is a problem with your bone marrow,a transplant can give you healthy new marrow. You could need a transplant because of a disease,such as bone marrow diseases or cancers like leukemia kemia or lymphoma.Or you might need one if a strong cancer treatment kills your healthy blood cells.People with cancer sometimes donate bone marrow before treatment to be transplanted later. But often the new marrow comes from a donor,either a close family member or someone unrelated.The healthy cells for a transplant can come from three sources:bone marrow;peripheral (circulating) blood that has an increased number of healthy blood-forming cells(also called peripheral blood stem cells or PBSC);umbilical cord blood that is collected after a baby is born.If you need an allogeneic transplant,your doctor will look for a marrow donor or cord blood unit that matches your HLA tissue type.HLA stands for human leukocyte antigen,a markei your immune system uses to recognize which cells belong in your body and which do not.Before your body can receive the healthy cells,the diseased cells must be destroyed.This is done using chemotherapy and sometimes radiation. The destruction of diseased cells is called a preparative regimen or a conditioning regimen.On the day of transplant,the cells from the marrow donor or cord blood unit are infused intravenously(go into your body through a large vein).These healthy cells move into the spaces inside your bones where they create new marrow. They grow and make healthy new red blood cells,white blood cells,and platelets.We can infer from this passage that_________.A:bone marrow transplantation requires five proceduresB:bone marrow transplantation is complexC:people with leukemia must need transplantationD:people with cancer must donate bone marrow before treatment
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单选题Passage 2Several research teams have found that newborns prefer their mothers' voices over those of other people. Now a team of scientists has gone an intriguing step further: they have found that newborns cry in their native language.We have provided evidence that language begins with the very first cry melodies,says Kathleen Wermke of the University of Wirzburg, Germany, who led the research.The dramatic finding of this study is that not only are newborns capable of producing different cry melodies, but they prefer to produce those melody patterns that are typical for the ambient language they have heard during their fetal life, within the last trimester,said Wermke.Contraryto orthodox interpretations, these data support the importance of human infants' crying for seeding language development.It had been thought that babies' cries are constrained by their breathing patterns and respiratory apparatus, in which case a crying baby would sound like a crying baby no matter what the culture is, since babies are anatomically identical.The prevailing opinion used to be that newborns could not actively influence their production of sound,says Wermke. This study refutes that claim: since babies cry in different languages, they must have some control(presumably unconscious) over what they sound like rather than being constrained by the acoustical properties of their lungs, throat, mouth, and larynx. If respiration alone dictated what a cry sounded like, all babies would cry with a falling-pitch pattern, since that's what happens as you run out of breath and air pressure on the throat's sound-making machinery decreases. French babies apparently didn't get that memo.German and French infants produce different types of cries, even though they share the same physiology,the scientists point out.The French newborns produce ' nonphysiological' rising patterns,showing that the sound of their cries is under their control.Although phonemes-speech sounds such as kiorsh-don't cross the abdominal barrier and reach the fetus, so-called prosodic characteristics of speech do. These are the variations in pitch, rhythm, and intensity that characterize each language. Just as newborns remember and prefer actualsongs that they heard in utero, it seems, so they remember and prefer both the sound of Mom's voice and the melodic signature of her language.The idea of the study wasn't to make the sound of a screaming baby more interesting to listeners-good luck with that-but to explore how babies acquire speech. That acquisition, it is now clear, begins months before birth, probably in the third trimester. Newborns not only have memorized the main intonation patterns of their respective surrounding language but are also able to reproduce these patterns in their own [ sound] production,conclude the scientists. Newborns'cries are already tuned toward their native language, giving them a head start on sounding French or German (or, presumably, English or American or Chinese or anything else: the scientists are collecting cries from more languages). This is likely part of the explanation for how babies develop spoken language quickly and seemingly without effort. Sure, we may come into the world wired for language(thank you, Noam Chomsky), but we also benefit from the environmental exposure that tells us which language.Until this study, scientists thought that babies became capable of vocal imitation no earlier than12 weeks of age. That's when infants listening to an adult speaker producing vowels can parrot the sound. But that's the beginning of true speech. It's sort of amazing that it took this long for scientists to realize that if they want to see what sounds babies can perceive, remember, and play back, they should look at the sound babies produce best. So let the little angel cry: she's practicing to acquire language.Why do German and French babies produce different types of cries according to the research?A
Because they can control what they hear.B
Because they can control their different breathing patterns.C
Because they don't share the same physiological structure.D
Because they can somehow control their sound production.
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单选题Passage 2Several research teams have found that newborns prefer their mothers' voices over those of other people. Now a team of scientists has gone an intriguing step further: they have found that newborns cry in their native language.We have provided evidence that language begins with the very first cry melodies,says Kathleen Wermke of the University of Wirzburg, Germany, who led the research.The dramatic finding of this study is that not only are newborns capable of producing different cry melodies, but they prefer to produce those melody patterns that are typical for the ambient language they have heard during their fetal life, within the last trimester,said Wermke.Contraryto orthodox interpretations, these data support the importance of human infants' crying for seeding language development.It had been thought that babies' cries are constrained by their breathing patterns and respiratory apparatus, in which case a crying baby would sound like a crying baby no matter what the culture is, since babies are anatomically identical.The prevailing opinion used to be that newborns could not actively influence their production of sound,says Wermke. This study refutes that claim: since babies cry in different languages, they must have some control(presumably unconscious) over what they sound like rather than being constrained by the acoustical properties of their lungs, throat, mouth, and larynx. If respiration alone dictated what a cry sounded like, all babies would cry with a falling-pitch pattern, since that's what happens as you run out of breath and air pressure on the throat's sound-making machinery decreases. French babies apparently didn't get that memo.German and French infants produce different types of cries, even though they share the same physiology,the scientists point out.The French newborns produce ' nonphysiological' rising patterns,showing that the sound of their cries is under their control.Although phonemes-speech sounds such as kiorsh-don't cross the abdominal barrier and reach the fetus, so-called prosodic characteristics of speech do. These are the variations in pitch, rhythm, and intensity that characterize each language. Just as newborns remember and prefer actualsongs that they heard in utero, it seems, so they remember and prefer both the sound of Mom's voice and the melodic signature of her language.The idea of the study wasn't to make the sound of a screaming baby more interesting to listeners-good luck with that-but to explore how babies acquire speech. That acquisition, it is now clear, begins months before birth, probably in the third trimester. Newborns not only have memorized the main intonation patterns of their respective surrounding language but are also able to reproduce these patterns in their own [ sound] production,conclude the scientists. Newborns'cries are already tuned toward their native language, giving them a head start on sounding French or German (or, presumably, English or American or Chinese or anything else: the scientists are collecting cries from more languages). This is likely part of the explanation for how babies develop spoken language quickly and seemingly without effort. Sure, we may come into the world wired for language(thank you, Noam Chomsky), but we also benefit from the environmental exposure that tells us which language.Until this study, scientists thought that babies became capable of vocal imitation no earlier than12 weeks of age. That's when infants listening to an adult speaker producing vowels can parrot the sound. But that's the beginning of true speech. It's sort of amazing that it took this long for scientists to realize that if they want to see what sounds babies can perceive, remember, and play back, they should look at the sound babies produce best. So let the little angel cry: she's practicing to acquire language.Which of the following is closest in meaning to the underlined word ambientin Paragraph 2?A
Surrounding.B
Familiar.C
Foreign.D
Local.
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名词解释题异嗜性抗原（heterophilic antigen）
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