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The Delta Sxrb interval of the mouse Y chromosome is critical for spermatogenesis and expression of the male-specific minor transplantation antigen H-Y. Several genes have been mapped to this interval and each has a homologue on the X chromosome. Four, Zfy1 , Zfy2 , Ube1y and Dffry , are expressed specifically in the testis and their X homologues are not transcribed from the inactive X chromosome. A further two, Smcy and Uty , are ubiquitously expressed and their X homologues escape X-inactivation. Here we report the identification of another gene from this region of the mouse Y chromosome. It encodes the highly conserved eukaryotic translation initiation factor eIF-2gamma. In the mouse this gene is ubiquitously expressed, has an X chromosome homologue which maps close to Dmd and escapes X-inactivation. The coding regions of the X and Y genes show 86% nucleotide identity and encode putative products with 98% amino acid identity. In humans, the eIF-2gamma structural gene is located on the X chromosome at Xp21 and this also escapes X-inactivation. However, there is no evidence of a Y copy of this gene in humans. We have identified autosomal retroposons of eIF-2gamma in both humans and mice and an additional retroposon on the X chromosome in some mouse strains. Ark blot analysis of eutherian and metatherian genomic DNA indicates that X-Y homologues are present in all species tested except simian primates and kangaroo and that retroposons are common to a wide range of mammals. These results shed light on the evolution of X-Y homologous genes.   相似文献   
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BACKGROUND: National guidelines are rarely followed by immediate changein clinical behaviour. We present our experience of an activeeducational method for local development and implementationof a guideline. OBJECTIVE: To evaluate the effectiveness of a participative method fordeveloping local clinical guidelines. METHODS: A trial in a district of the effect of guideline developmentincorporating active participation of intended recipients onsubsequent relevant prescribing. It was carried out in WirralFamily Health Services Authority district (the Wirral peninsula)comprising 69 general practices covering a population of 345763. An exemplar guideline on ‘hypertension in the elderly’was developed by the method described. The principal recommendeddrug was bendrofluazide 2.5 mg once daily. The differences inprescribed daily doses (PDD) of bendrofluazide 2.5 mg tabletsper quarter per 1000 prescribing units (age-weighted population)between the intervention district and England as a whole wasmeasured. RESULTS: Comparison of the intervention district with England data demonstratesa median difference of 122.49 PDD before and 206.34 PDD afterguideline production, this change is statistically highly significant(Mann-Whitney two-tailed P < 0.0001; 95% CL = 36.51–104.77).Grouped regression analysis shows no significant difference(0.89) in slope gradients before guideline production (P = 0.35,95% CL = –3.97–5.76), but the difference in slopegradients after (12.95) is statistically highly significant(P < 0.0001; 95% CL = 8.17–17.73). The data suggeststhat the change in clinical behaviour persisted for at leasttwo years. CONCLUSION: Participation of intended recipient general practitioners andlocal specialists in the development of a guideline by an activeeducational method as described was followed by a favourablechange in clinical behaviour which persisted for at least twoyears. Keywords. Clinical guidelines, development, evaluation, implementation, participation.  相似文献   
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目的探讨呼吸重症监护病房(respiratoryintensivecareunit,RICU)中患者出现谵妄的病因。方法对2010—06/2012—06月在作者医院RICU住院期间出现谵妄的患者进行回顾性分析,同期随机抽取相同例数未出现谵妄的患者作为对照组,进行比较分析。结果住院期间出现谵妄的患者共30例,发生率为8.2%(30/362),年龄多在70岁以上,男女无明显差异。南原发病引起的谵妄占53.3%(16/30),其中以肺部感染、慢性阻塞性肺疾病、呼吸衰竭、心力衰竭多见,40%患者需要机械通气。药物因素引起的谵妄占33.3%(10/30),以喹诺酮类、糖皮质激素类、茶碱类药物多见。由个人因素和ICU环境因素引起的谵妄占13.3%(4/30)。与对照组比较,谵妄组病死率无明显增加,但住院时间长[(16±5)d vs.(12±4)d,P〈0.05],住院费用高。结论通过积极处理原发病,去除诱因及有针对性地对患者进行心理疏导,有助于降低RICU谵妄发生率。  相似文献   
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Fenech  MF; Dreosti  IE; Rinaldi  JR 《Carcinogenesis》1997,18(7):1329-1336
Deficient levels of folic acid and vitamin B12 are associated with elevated chromosome damage rate and high concentrations of homocysteine in the blood. We have therefore performed a study to determine the prevalence of folate deficiency, vitamin B12 deficiency and hyperhomocysteinemia in 64 healthy men aged between 50 and 70 years, and evaluate the relationship of these micronutrient levels in the blood with the micronucleus frequency in peripheral blood lymphocytes. We also performed a placebo-controlled, double-blind intervention study to determine whether supplementation of the diet with a daily dose of 0.7 mg (as a supplement in cereal) or 2.0 mg (in a tablet) over a period of 4 months resulted in a significant alteration of folate status, homocysteine status and the micronucleus index. Twenty-three per cent of the men were serum folate deficient (<6.8 nmol/l), 16% were red blood cell folate deficient (<317 nmol/l), 4.7% were vitamin B12 deficient (<150 pmol/l) and 37% has plasma homocysteine levels >10 micromol/l. In total, 56% of the men had one or more abnormal blood values for folate, vitamin B12 or homocysteine. The micronucleus index of these men (n = 34) in cytokinesis-blocked binucleated cells (19.2 +/- 1.1) was significantly elevated (P = 0.02) when compared to the micronucleus index of the rest of the men who had normal levels of folate, vitamin B12 and homocysteine (16.3 +/- 1.3, n = 30). Interestingly, the micronucleus index in men with normal folate and vitamin B12, but homocysteine levels >10 micromol/l (19.4 +/- 1.7, n = 15) was also significantly higher (P = 0.05) when compared to those with normal folate, vitamin B12 and homocysteine. This novel result was also supported by the observation that the micronucleus index and plasma homocysteine were significantly (P = 0.0086) and positively correlated (r2 = 0.172) in those subjects who were not deficient in folate or vitamin B12. The micronucleus index was not significantly correlated with folate indices, but there was a significant (P = 0.013) negative correlation with serum vitamin B12 (r2 = 0.099). Daily supplementation of the diet with 0.7 mg free folic acid in cereal for 2 months followed by 2.0 mg free folic acid via a tablet produced a 4- fold increase in plasma folate, a 2.6-fold increase in red blood cell folate and a 11% reduction in plasma homocysteine; however, these changes were not accompanied by a reduction in the micronucleus index. In conclusion, it is apparent that elevated homocysteine status, in the absence of vitamin deficiency and low, but not deficient, vitamin B12 status are important risk factors for increased chromosome damage in lymphocytes.   相似文献   
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BACKGROUND: Drinking capacity is often reduced in functional dyspepsia. Drink tests may therefore have diagnostic potential. A simple drink test in combination with ultrasonography was applied in this study, the aim being to find the best drink for this test. METHODS: On separate days, 10 patients with functional dyspepsia (FD) and 10 healthy controls (C) drank three different test meals (Nutridrink 150 kcal/100 mL, meat soup 4 kcal/100 mL and water) at a rate of 100 mL/min until maximal drinking capacity. Intragastric volume at maximal drinking capacity was determined using 3-dimensional ultrasonography. RESULTS: Drinking capacity (P < 0.05) and intragastric volume (P < 0.01) were significantly lower in patients than in the controls with the meat soup meal, but not with Nutridrink or water. Gastric emptying distinguished significantly (P < 0.05) between patients and controls only with Nutridrink. Gastric emptying of Nutridrink was significantly correlated to the rate by which nausea was induced (P = 0.02), while gastric emptying of meat soup was significantly negatively correlated to the rate by which fullness was induced (P < 0.05). Receiver operating characteristic (ROC) analysis indicated that optimal discrimination between patients and controls was obtained by the combined test results of symptoms per intragastric volume using meat soup as the test meal. CONCLUSION: For the non-invasive diagnosis of functional dyspepsia by a rapid drink test in combination with ultrasonography, a meat soup meal is preferable compared to Nutridrink or water.  相似文献   
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