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1). Celiac Sprue■(一)■1.Celiac sprue， also known as celiac disease and gluten-sensitive enteropathy， is characterized by malabsorption resulting from inflammatory injury to the mucosa of the small intestine after the ingestion of wheat gluten or related rye and barley proteins.There is clinical and histologic improvement on a strict gluten-free diet， and relapse when dietary gluten is reintroduced.Accounts of celiac sprue date back to the first century A.D.It was not until the 1940s， however， that the link to gluten ingestion was established； Dickc， a Dutch pediatrician， observed that the condition of children with celiac sprue improved during the food shortages of World War I，only to relapse after cereal supplies were restored.Until fairly recently， celiac sprue was considered uncommon in the United States，with an estimated prevalence of 1 per 3， 000 population.However， greater awareness of its presentations and the availability of new， accurate serologic tests have led to the realization that celiac sprue is relatively common， affecting 1 of every 120 to 300persons in both Europe and North America.■2.The true prevalence of celiac sprue is difficult to ascertain， because many patients have atypical symptoms or none at all A large， multicenter Italian study identified seven new cases of celiac sprue in children for each patient with established disease.The highest reported prevalence is in Western Europe and in places where Europeans emigrated，notably North America and Australia.Celiac sprue is also found in parts of northwest India， and it may be underdiagnosed in South America， North Africa， and Asia.It is rare among people from a purely African-Caribbean， Chinese， or Japanese background.In most series there is a slight female preponderance.■3.Celiac sprue results from an inappropriate T-cell-mediated immune response against ingested gluten in genetically predisposed people.The importance of genetic factors is supported by the approximately 10 percent prevalence of the disease among first- degree relatives.Over 95 percent of patients with celiac sprue express the HLA-DQ(α1 * 501，β1 * 02) heterodimer ( HLA-DQ2)，which preferentially presents gluten derived gliadin peptides on its antigen-presenting groove to stimulate intestinal mucosal T cells.The enzyme tissue transglutaminase is one of the targets of the autoimmune response in celiac sprue.The modification of gliadin by host tissue transglutaminase has a key role in enhancing the gliadin-specific T-cell response， and a single tissue transglutaminase modified peptide is the dominant a-gliadin T cell epitope and may be a target for antigen-specific peptide therapy.■4.Classically， infants with celiac sprue present between the ages of 4 and 24 months with impaired growth， diarrhea， and abdominal distention.Vomiting is common in young .infants， as are pallor and edema.The onset of symptoms is gradual and follows the introduction of cereals into the diet.The velocity of weight gain slowly decreases before weight loss ensues.Some children present with constipation， although diarrhea is more typical.Patients with severe， untreated celiac sprue may present with short statue，pubertal delay， iron and folate deficiency with anemia， and rickets.Atypical celiac sprue is usually seen in older children or adolescents， who often have no overt features of malabsorption.In addition to recurrent abdominal pain， hypertransaminasemia， recurrent aphthous stomatitis， arthralgia， and defects in dental enamel， children may have behavioral disturbances such as depression， may be irritable， and may perform poorly in school.■5.The diagnosis of celiac sprue is increasingly being made in adults.Approximately50 percent of adult patients do not have clinically significant diarrhea.iron- deficiency anemia is now the most common clinical presentation in adults with celiac sprue.Other laboratory abnormalities include macrocytic anemia due to folate (or， rarely， vitamin B12)deficiency， coagulopathy resulting from vitamin K deficiency， or vitamin D deficiency leading to hypocalcemia and an elevated alkaline phosphatase level.Other increasingly recognized extraintestinal manifestations include bone fractures， infertility， psychiatric syndromes， and various neurologic conditions ，including peripheral neuropathy， ataxia，and seizures.■6.The availability of highly sensitive and specific serologic markers greatly facilitates the diagnosis of celiac sprue.These serologic tests are used to evaluate patients with suspected disease， monitor adherence and response to a gluten- free diet， and screen patients with atypical， extraintestinal manifestations.IgA antiendomysial antibodies are usually detected by indirect immunofluorescence with the use of sections of human umbilical cord or，less commonly， monkey esophageal smooth muscle.The reported sensitivity and specificity of antiendomysial antibodies are 85 to 98 percent and 97 to 100percent， respectively.■7.Histologic examination of a biopsy specimen of the small intestine remains the diagnostic gold standard for celiac sprue.In current practice， most biopsies in children and adults are performed during upper endoscopy.Endoscopy is more reliable than previous capsule biopsy techniques， because it allows multiple specimens to be obtained， thus reducing sampling error， and because， in many cases， examination of the upper gastrointestinal tract may in itself be indicated (e.g，in iron deficiency anemia ).Specimens should be obtained from the distal duodenum ( second or third part) to avoid the architectural distortion produced by Brunner′s glands or peptic duodenitis.Absent，flattened， or scalloped duodenal folds are not specific for celiac sprue.■8.Because a gluten-free diet represents a lifetime commitment， is more expensive than a normal diet， and may limit patients socially， especially children and teenagers， it should never be recommended unless the diagnosis of celiac sprue is firmly established.There is no role for an empirical therapeutic trial of gluten withdrawal because a patient′s response is often equivocal and because the abnormal findings on both the serologic tests and small-bowel biopsy may revert to normal， making subsequent definitive diagnosis difficult.■(二)■Celiac sprue is a relatively common enteropathy which is correlated with the ingestion of dietary ( )It is difficult to determine the real prevalence of the disease because of ( )symptoms in the patients.An ( )immune response against ingested gluten is likely to result in celiac sprue.Children and adults with celiac sprue present with a wide ( )of clinical manifestations.Methods for the diagnosis of celiac sprue include serologic tests and biopsy of the small intestine taken as diagnostic( )standard.A gluten free diet will not be recommended to the patients until a definite ( )is made.Choose the correct heading for Paragraph 7 ( )
A.Pathogenesis of celiac sprue
B.Clinical presentations of celiac sprue in adults
C.Treatment of celiac sprue with a gluten-free diet
D.Causes and diagnosis history of celiac sprue
E.Treatment of celiac sprue with multivitamin intake
F.Diagnosis of celiac sprue with serologic tests
G.Clinical manifestations in children with celiac sprue
H.Diagnosis of celiac sprue with biopsy of the small intestine
I.Epidemiological features of celiac sprue
J.Refractory sprue and enteropathy-associated T-cell lymphoma

正確答案：H
2). (一)■Bartter′s Syndrome■1 Bartter′s syndrome is a rare， genetically heterogeneous disorder characterized by renal salt wasting， hypokalemic metabolic alkalosis， and secondary hyperaldosteronism with normal to low blood pressure.Two distinct presentations of the syndrome exist： antenatal Bartter′s syndrome and classical Bartter′s syndrome.Both forms are inherited as autosomal recessive traits.■2 Patients with antenatal Bartter′s syndrome may carry loss of-function mutations in the genes encoding the furosemide-sensitive sodium- potassium-chloride cotransporter NKCC2， the inwardly rectifying potassium channel ROMK， or the chloride channel-subunit barttin.The concerted action of these transporters in the renal thick ascending limb of the loop of Henle ensures transcellular sodium chloride reabsorption in this nephron segment， which accounts for up to 20%to 25% of the total amount of filtered sodium chloride.In most persons with antenatal Bartter′s syndrome， compromised function of the thick ascending limb of the loop of Henle clinically manifests in utero and is characterized by massive saliuretic polyuria resulting in severe polyhydramnios and premature birth.■3 Postnatally， surviving patients with antenatal Bartter′s syndrome have persistent salt wasting， hypokalemic metabolic alkalosis， hypercalciuria， and a tendency toward nephrocalcinosis.Patients with antenatal Bartter′s syndrome are treated with fluid and salt supplementation and nonsteroidal antiinflammatory drugs， usually indomethacin.The latter agent should be administered with caution， because it may induce severe side effects， especially in preterm infants.Remarkably， some patients with antenatal Bartter′s syndrome have been described in whom the characteristic symptoms resolve spontaneously， fairly soon after birth.Until now， it was unclear whether this transient form of the condition was a distinct disorder.Now in the， Journal， Laghmani et al.describe a genetic cause of this transient renal salt-wasting phenotype.All the patients with transient antenatal Bartter′s syndrome who were available to the authors for study were male， so the authors predicted the involvement of an X-linked gene.■4 Indeed， by means of whole-exome sequencing and filtering for X-chromosomal variants， Laghmani et al.identified in one of these families a loss-of- function mutation in MAGED2， on the X chromosome， that co-segregated with the disorder.This was followed by the detection of additional pathogenic MAGED2 mutations in other patients with transient antenatal Bartter′s syndrome and in two families with idiopathic polyhydramnios.Overall， the study provides convincing evidence for the existence of a previously undescribed X-linked form of severe polyhydramnios with prematurity and transient antenatal Bartter′s syndrome caused by MAGED2 mutations.■5 Until recently， little was known about MAGED2 and the protein it encodes，melanoma associated antigen D2 (MAGE-D2).MAGED2 belongs to a family of genes that are widely expressed in embryonic and adult tissues and are reported to be involved in cell-cycle regulation， apoptosis， and neurogenesis.MAGED2 has mainly been studied in the context of cancer and， on the basis of its location on Xp11.2 (a hotspot locus for X-linked mental retardation)， has also been considered a candidate gene for X-linked intellectual disability.The finding of MAGED2 mutations in patients with transient antenatal Bartter′s syndrome unravels a new， conspicuous role for MAGE-D2 in fetal renal salt reabsorption and， as a consequence， in amniotic fluid homeostasis.Laghmani et al.show that in fetal and adult kidneys， MAGE-D2 is expressed in the thick ascending limb of the loop of Henle and distal convoluted tubules， where it stimulates the plasma- membrane expression and activity of the salt transporter NKCC2 and the thiazide -sensitive sodium chloride cotransporter NCC， respectively.The authors also found reduced expression of both NKCC2 and NCC in a fetal kidney from a patient with antenatal Bartter′s syndrome， which explains the massive salt loss.■6The molecular mechanism proposed by the authors involves two MAGED2binding partners： the molecular chaperone Hsp40 and cytoplasmic Gs alpha.Under normal circumstances (i.e.， in cells with wild-type MAGED2)， the salt transporters are protected from endoplasmic reticulum- associated degradation by Hsp40 and can thus “pass” this quality- control checkpoint in the endoplasmic reticulum.Gs-alpha may participate in the vasopressin- induced cyclic AMP-signaling cascade and thereby stimulate the activity of NKCC2 and NCC by promoting their insertion into the plasma membrane.■7The transient nature of the salt-wasting phenotype is intriguing but unexplained.Laghmani et al.speculate that higher sensitivity of adenylate cyclase activity to vasopressin during development or increasing levels of oxygenation in the kidney during gestation might underlie this transience.Another potential explanation is the postnatal maturation of the renal tubules， which may result in an altered composition of transporters or their regulators and thereby compensate for the molecular defect.This maturation phenomenon has already been proposed to explain the transient neonatal hyperkalemia in patients with antenatal Bartter′s syndrome caused by mutations of KCNJ1 (encoding ROMK).■8 The recognition of polyhydramnios with transient antenatal Bartter′s syndrome as a distinct X-linked phenotype has clinical implications.Although there are no extant data from clinical trials， we think that women known to be pregnant with a male fetus and who have unexplained severe polyhydramnios are candidates for genetic analysis of the fetus.An early genetic diagnosis would render other diagnostic measures for polyhydramnios unnecessary， and potentially harmful treatments， such as long term treatment with indomethacin， could possibly be avoided in the preterm infants who survive.■(二)■Renal salt wasting， hypokalemic metabolic alkalosis， and secondary hyperaldosternism with normal to low blood pressure are the typical characteristics of Batter′s syndrome一a rare， genetically heterogeneous disorder.In Antenatal Bartter′s syndrome， ( )function of the thick ascending limb of the loop of Henle is( )by massive saliuretic polyuria resulting in severe polyhydramnios and premature birth.Patients with antenatal Bartter′s syndrome are treated with fluid and salt ( )and nonsteroidal anti-inflammatory drugs， usually indomethacin.The studies of MAGED2 are mainly in the context of cancer and， on the basis of its location on Xp11.2， have also been considered a candidate gene for X-linked( )disability.The explanation of transient neonatal hyperkalemia in patients with antenatal Bartter′s syndrome caused by mutations of KCNJ1 has already been proposed to be explained by ( ).phenomenon.There are no extant data from clinical trials， however we think that women known to be pregnant with a male fetus and who have unexplained severe polyhydramnios are candidates for ( ) an analysis of the fetus.( )
A.diagnostic
B.characterized
C.transience
D.intellectual
E.supplementation
F.premature
G.compromised
H.maturation
I.involvement
J.reabsorption
A.genetic
A.administered

正確答案：E
3). (一)■Bartter′s Syndrome■1 Bartter′s syndrome is a rare， genetically heterogeneous disorder characterized by renal salt wasting， hypokalemic metabolic alkalosis， and secondary hyperaldosteronism with normal to low blood pressure.Two distinct presentations of the syndrome exist： antenatal Bartter′s syndrome and classical Bartter′s syndrome.Both forms are inherited as autosomal recessive traits.■2 Patients with antenatal Bartter′s syndrome may carry loss of-function mutations in the genes encoding the furosemide-sensitive sodium- potassium-chloride cotransporter NKCC2， the inwardly rectifying potassium channel ROMK， or the chloride channel-subunit barttin.The concerted action of these transporters in the renal thick ascending limb of the loop of Henle ensures transcellular sodium chloride reabsorption in this nephron segment， which accounts for up to 20%to 25% of the total amount of filtered sodium chloride.In most persons with antenatal Bartter′s syndrome， compromised function of the thick ascending limb of the loop of Henle clinically manifests in utero and is characterized by massive saliuretic polyuria resulting in severe polyhydramnios and premature birth.■3 Postnatally， surviving patients with antenatal Bartter′s syndrome have persistent salt wasting， hypokalemic metabolic alkalosis， hypercalciuria， and a tendency toward nephrocalcinosis.Patients with antenatal Bartter′s syndrome are treated with fluid and salt supplementation and nonsteroidal antiinflammatory drugs， usually indomethacin.The latter agent should be administered with caution， because it may induce severe side effects， especially in preterm infants.Remarkably， some patients with antenatal Bartter′s syndrome have been described in whom the characteristic symptoms resolve spontaneously， fairly soon after birth.Until now， it was unclear whether this transient form of the condition was a distinct disorder.Now in the， Journal， Laghmani et al.describe a genetic cause of this transient renal salt-wasting phenotype.All the patients with transient antenatal Bartter′s syndrome who were available to the authors for study were male， so the authors predicted the involvement of an X-linked gene.■4 Indeed， by means of whole-exome sequencing and filtering for X-chromosomal variants， Laghmani et al.identified in one of these families a loss-of- function mutation in MAGED2， on the X chromosome， that co-segregated with the disorder.This was followed by the detection of additional pathogenic MAGED2 mutations in other patients with transient antenatal Bartter′s syndrome and in two families with idiopathic polyhydramnios.Overall， the study provides convincing evidence for the existence of a previously undescribed X-linked form of severe polyhydramnios with prematurity and transient antenatal Bartter′s syndrome caused by MAGED2 mutations.■5 Until recently， little was known about MAGED2 and the protein it encodes，melanoma associated antigen D2 (MAGE-D2).MAGED2 belongs to a family of genes that are widely expressed in embryonic and adult tissues and are reported to be involved in cell-cycle regulation， apoptosis， and neurogenesis.MAGED2 has mainly been studied in the context of cancer and， on the basis of its location on Xp11.2 (a hotspot locus for X-linked mental retardation)， has also been considered a candidate gene for X-linked intellectual disability.The finding of MAGED2 mutations in patients with transient antenatal Bartter′s syndrome unravels a new， conspicuous role for MAGE-D2 in fetal renal salt reabsorption and， as a consequence， in amniotic fluid homeostasis.Laghmani et al.show that in fetal and adult kidneys， MAGE-D2 is expressed in the thick ascending limb of the loop of Henle and distal convoluted tubules， where it stimulates the plasma- membrane expression and activity of the salt transporter NKCC2 and the thiazide -sensitive sodium chloride cotransporter NCC， respectively.The authors also found reduced expression of both NKCC2 and NCC in a fetal kidney from a patient with antenatal Bartter′s syndrome， which explains the massive salt loss.■6The molecular mechanism proposed by the authors involves two MAGED2binding partners： the molecular chaperone Hsp40 and cytoplasmic Gs alpha.Under normal circumstances (i.e.， in cells with wild-type MAGED2)， the salt transporters are protected from endoplasmic reticulum- associated degradation by Hsp40 and can thus “pass” this quality- control checkpoint in the endoplasmic reticulum.Gs-alpha may participate in the vasopressin- induced cyclic AMP-signaling cascade and thereby stimulate the activity of NKCC2 and NCC by promoting their insertion into the plasma membrane.■7The transient nature of the salt-wasting phenotype is intriguing but unexplained.Laghmani et al.speculate that higher sensitivity of adenylate cyclase activity to vasopressin during development or increasing levels of oxygenation in the kidney during gestation might underlie this transience.Another potential explanation is the postnatal maturation of the renal tubules， which may result in an altered composition of transporters or their regulators and thereby compensate for the molecular defect.This maturation phenomenon has already been proposed to explain the transient neonatal hyperkalemia in patients with antenatal Bartter′s syndrome caused by mutations of KCNJ1 (encoding ROMK).■8 The recognition of polyhydramnios with transient antenatal Bartter′s syndrome as a distinct X-linked phenotype has clinical implications.Although there are no extant data from clinical trials， we think that women known to be pregnant with a male fetus and who have unexplained severe polyhydramnios are candidates for genetic analysis of the fetus.An early genetic diagnosis would render other diagnostic measures for polyhydramnios unnecessary， and potentially harmful treatments， such as long term treatment with indomethacin， could possibly be avoided in the preterm infants who survive.■(二)■Renal salt wasting， hypokalemic metabolic alkalosis， and secondary hyperaldosternism with normal to low blood pressure are the typical characteristics of Batter′s syndrome一a rare， genetically heterogeneous disorder.In Antenatal Bartter′s syndrome， ( )function of the thick ascending limb of the loop of Henle is( )by massive saliuretic polyuria resulting in severe polyhydramnios and premature birth.Patients with antenatal Bartter′s syndrome are treated with fluid and salt ( )and nonsteroidal anti-inflammatory drugs， usually indomethacin.The studies of MAGED2 are mainly in the context of cancer and， on the basis of its location on Xp11.2， have also been considered a candidate gene for X-linked( )disability.The explanation of transient neonatal hyperkalemia in patients with antenatal Bartter′s syndrome caused by mutations of KCNJ1 has already been proposed to be explained by ( ).phenomenon.There are no extant data from clinical trials， however we think that women known to be pregnant with a male fetus and who have unexplained severe polyhydramnios are candidates for ( ) an analysis of the fetus.( )
A.diagnostic
B.characterized
C.transience
D.intellectual
E.supplementation
F.premature
G.compromised
H.maturation
I.involvement
J.reabsorption
A.genetic
A.administered

正確答案：B

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