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81.
Polycystic Kidney Disease Re-evaluated: A Population-based Study   总被引:2,自引:0,他引:2  
A genetic register of all known cases of autosomal dominantpolycystic kidney disease occurring in South and Mid-Wales hasbeen established. In a population of 2.1 million, 209 familieswith affected members were identified, 303 of whom are currentlyalive, 70 on renal replacement therapy. An additional 551 caseswould be predicted amongst family members at 50 per cent and25 per cent risk, giving an apparent prevalence of 1:2459 inthe general population. Five possible new mutations were seenwhere adults with phenotypic autosomal dominant polycystic kidneydisease had both parents alive, age > 55 years with no cystsvisible on ultrasound. The take-on rate for renal replacementtherapy increased during 1970–79 but has apparently reacheda plateau of 4.8 cases per million population per year overthe last 8 years, despite a rapidly increasing acceptance ofuraemic patients as a whole (72/106/year in 1988–89).Considerably more patients with autosomal dominant polycystickidney disease aged over 50 years were started on treatmentin 1980–89 than in 1970–79, but the survival overallimproved with time. All cases of autosomal dominant polycystickidney disease reaching end-stage renal disease are now beingtreated, but the apparent clinical prevalence of this conditionin our region is less than half the supposed gene frequency,suggesting that undiagnosed cases have a benign prognosis.  相似文献   
82.
Cortical spreading depression (SD) has not been shown in the human neocortex by direct cortical recordings. However, animal studies suggest that cortical injury, such as that occurring during neurosurgical procedures, should result in the initiation of SD. It is possible that inhibition of SD by volatile anesthetic agents may partially explain the failure to observe SD in the human neocortex during surgery. This study examines the effect of the anesthetic agents α-chloralose, halothane, nitrous oxide and isoflurane on the initiation of cortical SD in the cat neocortex. SD was seen in 100% of cats anesthetized with α-chloralose ( n = 15), in 3 of 7 (42%) animals anesthetized with isoflurane ( p < 0.05, χ2 with Yates correction) and none of the animals ( n = 4, 6 hemispheric preparations) anesthetized with halothane ( p < 0.005, χ2 with Yates correction, halothane vs α-chloralose group). In all cases this inhibitory effect was reversible. In four animals the administration of nitrous oxide (66%) reduced the inspired concentration of isoflurane required to inhibit SD by 0.75%. This study suggests that halothane, and to a lesser extent isoflurane and nitrous oxide, protect against the initiation of cortical SD. This observation may partially explain why SD has not been demonstrated in human neocortex during surgery. Further studies are needed to determine if SD may occur under pathological conditions, such as during migraine with aura, where the cortex may be predisposed to SD.  相似文献   
83.
84.
目的通过分析我国双相情感障碍的文献分布,探讨我国双相情感障碍的发展趋势。方法采用文献计量学方法和MicrosoftExcel技术,通过利用中国生物医学文献数据库中收录的有关以双相情感障碍为主题的文献,从时间分布、单位分布、地域分布、期刊分布、第一作者分布和主要内容等方面,进行多角度文献分析。结果双相情感障碍文献的时间分布、单位分布、地域分布与地区经济发展密切相关;浙江常州全军精神卫生中心解放军第102医院、深圳市精神卫生研究所(深圳市精神卫生中心)、南京医科大学附属脑科医院及在以上单位工作的作者可视为该病的核心研究机构和研究者;《临床精神医学杂志》(6.67%)、《四川精神卫生》(5.14%)、《上海精神医学》(4.72%)、《中国神经精神疾病杂志》(4.16%)可视为该病研究的核心期刊;国内学者对该病的研究主要集中于临床药物治疗、临床诊断、临床病例报告(约占临床研究的61.98%)、流行病学调查(约占预防医学研究的63%)等方面,对于双相情感障碍预防方面(约占论文总数的28.97%)及合并外科疾病围手术期(约占临床研究的4.04%)的专题研究报道较少。结论双相情感障碍研究在国内尚处于初步研究阶段,各地区发展不平衡,对该病的预防和治疗认识不足。各地区应重视该病的防治工作,建立预警机制,制定相应防治措施,防止该病的流行和突发事件的发牛。  相似文献   
85.
目的应用超声手段探测儿童颈动脉内膜-中层厚度(IMT),探讨其与儿童肥胖类型的关系。方法依体质指数(BMI)、腰围身高比(WHtR)标准,入组外周性肥胖组160名(A组),内脏性肥胖150名(B组),正常体重儿童160名(正常对照组);应用超声手段探测各组儿童内脏脂肪厚度(VFT)和颈动脉内膜-中层厚度,比较3组间各项检测参数。结果内脏肥胖组VFT、IMT均高于外周性肥胖组及正常组,差异具有统计学意义(P〈0.05);外周性肥胖组VFT、IMT与正常组相似,差异没有显著性。结论IMT与肥胖类型相关,内脏性肥胖儿童VFT、IMT增加。实时超声检查技术为研究儿童肥胖类型提供了一种新的检测手段。  相似文献   
86.
CONTEXT: Recently, a quantitative trait locus for stature was reported on chromosome 3p26 in patients with type 2 diabetes. OBJECTIVE: Given that ghrelin is a peptide involved in GH release and located on 3p26, we hypothesized that variation within its gene (GHRL) may be responsible for the quantitative trait locus on 3p26. DESIGN: The evidence for linkage around GHRL was refined with the genotyping of an additional four microsatellites (D3S4545, D3S1537, D3S1597, and D3S3611), giving a total of 27 markers, followed by multipoint variance components linkage analysis. Probands from the linkage families were typed for five common single nucleotide polymorphisms (SNPs) within GHRL and tested for association with adult stature using haplotype trend regression. RESULTS: The maximum multipoint evidence for linkage between adult stature and the 27 microsatellites yielded an LOD score of 2.58 (P = 0.0003) between D3S1297 and D3S1304. Five common (frequency of > or =5%) SNPs were typed in the probands [two promoter SNPs (rs27647 and rs26802), two exonic (rs696217 and rs4684677), and one intronic (rs35683)] capturing 80% of the total common variation in GHRL. No association was found between any SNP (or haplotypes thereof) and adult stature. CONCLUSION: Common genetic variation within GHRL is not responsible for variation in adult stature in this population.  相似文献   
87.
目的:分析总结食管癌切除胸腹二区淋巴结清扫的手术疗效。方法:回顾分析1986年2月~2007年12月我院对中下段食管癌和上段食管癌分别采用Ivor—Lewis术式,即上腹正中、右胸后外侧二切口切除及Akiyama术式.即右胸后外侧、上腹正中、左颈部三切口切除,并作胸腹二区淋巴结清扫治疗胸段食管癌1690例的临床资料,总结胸腹二区淋巴结转移的发生率并随访1、3、5年的生存率。结果:全组手术切除率为97.86%(1690/1727)。全组有淋巴结转移782例,占46.27%,其中胸部淋巴结转移占38.93%(658/1690),腹部淋巴结转移占25.92%(438/1690),胸部淋巴结转移发生于最上纵隔位于气管食管沟及喉返神经旁占20.47%(346/1690),术后共有178例发生230例次各种并发症,总的并发症的发生率为13.6%(230/1690),其中肺部并发症为第一位,占34.3%,心律失常占17.4%,喉返神经损伤发生率为8.7%,吻合口瘘发生率为1.7%。术后1、3、5年的生存率分别为88.2%(1161/1316)、63.5%(634/998)和51.8%(331/639)。无淋巴结转移的5年生存率为65.2%(219/336),有淋巴结转移的5年生存率为32.3%(102/316)。结论:Ivor-Lewis术式和Akiyama术式胸腹腔有良好的显露,淋巴结清扫彻底、方便,尤其对右侧最上纵隔沿喉返神经旁淋巴结清扫便利。特别对有淋巴结转移的食管癌患者行胸、腹二区淋巴结清扫十分必要,能明显提高术后5年生存率。  相似文献   
88.
OBJECTIVE—Single nucleotide polymorphisms (SNPs) in the P2 promoter region of HNF4A were originally shown to be associated with predisposition for type 2 diabetes in Finnish, Ashkenazi, and, more recently, Scandinavian populations, but they generated conflicting results in additional populations. We aimed to investigate whether data from a large-scale mapping approach would replicate this association in novel Ashkenazi samples and in U.K. populations and whether these data would allow us to refine the association signal.RESEARCH DESIGN AND METHODS—Using a dense linkage disequilibrium map of 20q, we selected SNPs from a 10-Mb interval centered on HNF4A. In a staged approach, we first typed 4,608 SNPs in case-control populations from four U.K. populations and an Ashkenazi population (n = 2,516). In phase 2, a subset of 763 SNPs was genotyped in 2,513 additional samples from the same populations.RESULTS—Combined analysis of both phases demonstrated association between HNF4A P2 SNPs (rs1884613 and rs2144908) and type 2 diabetes in the Ashkenazim (n = 991; P < 1.6 × 10−6). Importantly, these associations are significant in a subset of Ashkenazi samples (n = 531) not previously tested for association with P2 SNPs (odds ratio [OR] ∼1.7; P < 0.002), thus providing replication within the Ashkenazim. In the U.K. populations, this association was not significant (n = 4,022; P > 0.5), and the estimate for the OR was much smaller (OR 1.04; [95%CI 0.91–1.19]).CONCLUSIONS—These data indicate that the risk conferred by HNF4A P2 is significantly different between U.K. and Ashkenazi populations (P < 0.00007), suggesting that the underlying causal variant remains unidentified. Interactions with other genetic or environmental factors may also contribute to this difference in risk between populations.The presence of type 2 diabetes susceptibility genes on chromosome 20 has been suggested by linkage scans in several populations. The 20q12–q13 region (Online Mendelian Inheritance in Man [OMIM] 603694) is the best replicated and harbors the gene HNF4A, mutations that lead to type 1 maturity-onset diabetes of the young (OMIM 125850). Evidence for association between SNPs in the β-cell P2 promoter region of HNF4A has been recognized in Finnish (1) and Ashkenazi (2) populations, with data suggesting that the HNF4A P2 SNPs (or variants in strong linkage disequilibrium with them) contribute to the linkage signal on chromosome 20q (1,2). Association with HNF4A promoter SNPs has been replicated in some (37) but not all (812) populations tested. In other populations, there was evidence for association with SNPs or haplotypes in the HNF4A region other than the P2 SNPs (10,1315). More recently, the association between HNF4A promoter SNPs and type 2 diabetes has been confirmed in Scandinavians but not in a broader meta-analysis with additional populations (16), suggesting that P2 SNPs confer varying risk effects in different populations, possibly due to the underlying causal variant not having been identified. We investigated a 10-Mb interval (38.1–48.2 Mb National Center for Biotechnology Information build 35) centered around HNF4A, including genotypes from 4,608 nonredundant (r2 < 1) SNPs (one SNP per 2 Kb, on average) in five type 2 diabetic case-control populations, to evaluate whether we could confirm and refine the association signal in Ashkenazim and whether this association was also present in U.K. populations. We were also interested in assessing whether there was evidence for additional association signals within this broader interval. We tested an Ashkenazi type 2 diabetes case-control study (n = 998), including novel samples (n = 531) not previously tested for linkage or association with HNF4A P2 SNPs (2); two U.K. population-based case-control studies where linkage and association studies with HNF4A P2 had not be carried out (n = 2,189); and two additional U.K. case-control collections (n = 1,842), with one enriched for earlier-onset type 2 diabetes where linkage studies had not been done but that showed suggestive association with HNF4A P2 SNPs (4) and one that included samples where, despite no evidence of linkage to chromosome 20q, association of HNF4A P2 SNPs with type 2 diabetes risk had previously been suggested (4,17).  相似文献   
89.
目的建立室内质控参考品以鉴别诊断试剂的质量和控制操作误差,提高乙型肝炎病毒表面抗原的检测准确度。方法以国家标准品为标准制备灵敏度系列参考品、特异性参考品及精密性参考品。检测其稳定性,并进行同厂家、不同批号试剂的比较及不同厂家、三批试剂的比较。结果制备的室内质控参考品在-20℃与4℃保存3~4周检测结果无统计学差异。采用同一厂家、不同批号的HBsAg诊断试剂检测室内质控参考品,结果无统计学差异。采用不同厂家、同一批号的HBsAg诊断试剂检测结果有统计学差异。结论我们建立的室内质控参考品适宜作HBsAg室内质控,提醒我们在更换试剂厂家时应特别注意室内质控参考品的变化。  相似文献   
90.
Levin  DC; Gardiner  GA  Jr 《Radiology》1987,164(3):675-680
For many years, atherosclerotic coronary artery lesions have been described by angiographers only in terms of location and degree of narrowing. However, it has become apparent that coronary stenoses generally have distinct morphologic features that can be recognized at angiography and that allow them to be classified as either "simple" or "complex" plaques. Complex plaques are those characterized by ulcerated or ruptured surfaces, subintimal hemorrhage, superimposed partially occluding thrombi, recanalized thrombi, or some combination. Pathologic studies have shown a very high frequency of these lesions at sites of total thrombotic occlusion of coronary arteries. Clinical and angiographic studies have demonstrated a high frequency of such lesions in living patients with both unstable angina and acute myocardial infarction. The presence of complex stenoses has also been found to increase the risk of future myocardial infarction. Plaque morphology thus appears to significantly affect the prognosis of patients with coronary disease and should be carefully evaluated in interpretation of all coronary angiograms.  相似文献   
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