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1.
目的探讨衰老对大鼠阴茎组织结构、NO(nitric oxide)-cGMP(cvclic Guanosine Monophosphate)通路及端粒酶活性的影响作用。方法本课题以不同月龄大鼠阴茎组织及培养的平滑肌细胞为研究对象,检测不同月龄大鼠阴茎组织中NO量、NOS(Nitric Oxide Synthase)活性、cGMP量、端粒酶活性及海绵体结构的变化,并比较大鼠、人阴茎组织及大鼠原代海绵体平滑肌细胞的端粒酶活性。结果(1)大鼠阴茎组织中NO量、NOS活性均先升高后降低,各月龄组间有显著差异。阴茎组织cGMP含量逐渐降低,各月龄组间差别显著;(2)随龄增加,平滑肌纤维逐渐减少,胶原纤维增多,粗大成团,窦状隙变少、变窄:(3)大鼠阴茎组织端粒酶活性以2月龄活性最高,随龄增加逐渐下降。人阴茎组织中无端粒酶活性。结论(1)衰老对大鼠阴茎组织结构、NO.cGMP通路及端粒酶活性有显著影响,提示衰老与ED关系密切;(2)大鼠阴茎组织有端粒酶活性,可作为研究细胞衰老与ED关系有关端粒酶的模型。 相似文献
2.
Spencer S. Jones MStat Todd L. Allen MD Thomas J. Flottemesch PhD Shari J. Welch MD 《Academic emergency medicine》2006,13(11):1204-1211
Background Emergency department (ED) overcrowding has become a frequent topic of investigation. Despite a significant body of research, there is no standard definition or measurement of ED crowding. Four quantitative scales for ED crowding have been proposed in the literature: the Real‐time Emergency Analysis of Demand Indicators (READI), the Emergency Department Work Index (EDWIN), the National Emergency Department Overcrowding Study (NEDOCS) scale, and the Emergency Department Crowding Scale (EDCS). These four scales have yet to be independently evaluated and compared. Objectives The goals of this study were to formally compare four existing quantitative ED crowding scales by measuring their ability to detect instances of perceived ED crowding and to determine whether any of these scales provide a generalizable solution for measuring ED crowding. Methods Data were collected at two‐hour intervals over 135 consecutive sampling instances. Physician and nurse agreement was assessed using weighted κ statistics. The crowding scales were compared via correlation statistics and their ability to predict perceived instances of ED crowding. Sensitivity, specificity, and positive predictive values were calculated at site‐specific cut points and at the recommended thresholds. Results All four of the crowding scales were significantly correlated, but their predictive abilities varied widely. NEDOCS had the highest area under the receiver operating characteristic curve (AROC) (0.92), while EDCS had the lowest (0.64). The recommended thresholds for the crowding scales were rarely exceeded; therefore, the scales were adjusted to site‐specific cut points. At a site‐specific cut point of 37.19, NEDOCS had the highest sensitivity (0.81), specificity (0.87), and positive predictive value (0.62). Conclusions At the study site, the suggested thresholds of the published crowding scales did not agree with providers' perceptions of ED crowding. Even after adjusting the scales to site‐specific thresholds, a relatively low prevalence of ED crowding resulted in unacceptably low positive predictive values for each scale. These results indicate that these crowding scales lack scalability and do not perform as designed in EDs where crowding is not the norm. However, two of the crowding scales, EDWIN and NEDOCS, and one of the READI subscales, bed ratio, yielded good predictive power (AROC >0.80) of perceived ED crowding, suggesting that they could be used effectively after a period of site‐specific calibration at EDs where crowding is a frequent occurrence. 相似文献
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目的评价西地那非治疗ED的有效性。方法通过中国生物医学文摘光盘(CBMdisc 2004新版)和清华同方数据库中CHKD期刊全文库检索公开发表的中文文献。凡摘要或方法中出现随机对照字样,无论有无盲法均予纳入。对纳入的试验设计特征用Jadad计分评价。以IIEF中Q3和Q4评分及IIEF总评分为疗效指标,采用RevMan4.1软件进行Meta分析。结果共有9个随机对照试验被纳入。其中6个为Jadad计分3分以上高质量试验。5个试验的IIEF Q3和Q4评分meta分析,OR=8.83,95%CI为(6.67,11.69),P<0.0001。4个高质量试验的IIEF总评分meta分析OR=13.76,95%CI为(9.50,19.92),P<0.0001。显示西地那非能够显著提高ED患者的疗效指标。结论西地那非能有效改善男性勃起功能,是一种有效治疗ED的口服药物。 相似文献
6.
目的 探讨Fas/Apo-1(CD95)在下肢静脉性溃疡的表达及意义.方法 采用流式细胞技术、半定量逆转录-聚合酶链反应(RT-PCR)和免疫组织化学方法检测不同体位下肢外周血和局部皮肤Fas/Apo-l(CD95)的表达.结果 溃疡组平卧位、下垂位血液中Fas/Apo-1(CD95)阳性细胞数分别为41.45±14.25、40.20±12.42,mRNA为0.74±0.33、0.78±0.22,皮肤中阳性细胞数为42.62±22.19、46.50±20.12,分别与无溃疡组和对照组比较,差异均有统计学意义(P<0.05);无溃疡组和对照组比较,差异无统计学意义(P>0.05);不同体位之间Fas/Apo-1(CD95)阳性细胞数和含量比较,差异无统计学意义(P>0.05).结论 Fas/Apo-1高表达可能与下肢静脉性溃疡发生密切相关. 相似文献
7.
Gail D'Onofrio Edward Bernstein Judith Bernstein Robert H. Woolard Phillip A. Brewer Sandra A. Craig Brian J. Zink 《Academic emergency medicine》1998,5(12):1200-1209
Abstract. Medical and social problems related to alcohol use are frequently seen in the ED. Often, the tempo of emergency medicine practice seems to preclude assessment beyond that required by the acute complaint. However, detection of ED patients with alcohol problems can occur using brief screening tools. This article was developed by members of the SAEM Substance Abuse Task Force, and describes screening tools that have been used successfully to identify atrisk and dependent drinkers. Their brevity, reproducibility, and accuracy vary somewhat, but screening can be realistically performed in the busy ED setting. The early detection of patients with alcohol problems would provide the opportunity for early intervention, and may reduce subsequent morbidity and mortality in this patient population. 相似文献
8.
细粒棘球蚴95抗原基因的克隆及原核表达质粒的构建 总被引:9,自引:2,他引:7
目的:克隆细粒棘球蚴95(Eg95)抗原基因,构建携带目的基因的原核表达载体,为细粒棘球蚴抗原的免疫保护机制研究提供材料。方法:应用PCR方法从细粒棘球蚴cDNA文库中克隆获得Eg95抗原基因,将其克隆至pUCm-T载体,测序确定其正确性。利用定向克隆技术将Eg95抗原基因片段克隆至原核表达质粒pET28上,根据选择标记的卡那霉素抗性基因筛选到阳性克隆,通过酶切分析和PCR鉴定筛选出阳性克隆,测序确定序列。结果:测序表明所有pET28-Eg95阳性克隆均为正确连接95抗原基因的重组质粒。结论:pET28-Eg95可以进一步用于重组蛋白的表达及抗细粒棘球蚴感染的实验研究。 相似文献
9.
目的 编制急诊科(emergency department,ED)护士对新发传染病(emerging infectious diseases,EID)知信行(knowledge attitude practice,KAP)调查问卷,并进行信效度检验。方法 以KAP理论为基础,通过文献回顾、德尔菲专家函询形成问卷初稿;于2021年5月方便抽样上海市3所三级甲等综合医院293名ED护士进行预调查,完成问卷条目筛选和信效度检验。结果 形成含有34个条目的ED护士对EID知信行调查问卷,其中知识维度12个条目、态度维度10个条目、行为维度12个条目。问卷整体Cronbach's α系数为0.926,各维度Cronbach's α系数为0.617~0.968;问卷整体分半信度为0.846,各维度分半信度为0.614~0.958。问卷水平内容效度指数(scale-level content validity index,S-CVI)为0.99,条目水平内容效度指数(item-level content validity index,I-CVI)为0.99~1.00;探索因子分析显示,知识、态度、行为3个维度分别提取公因子4个、1个、2个,累计方差贡献率分别为50.192%、78.319%、73.341%,问卷整体累计方差贡献率67.242%;验证因子分析显示,问卷整体及各维度拟合度较好。结论 EID知信行调查问卷具有良好的信效度,可作为ED护士对EID KAP的评估工具。 相似文献
10.
Seeliger F Drögemüller C Tegtmeier P Baumgärtner W Distl O Leeb T 《Journal of comparative pathology》2005,132(4):346-349
A 2-year-old German Holstein bull was identified as a carrier of a mutation within the X-chromosomal ED1 gene, which encodes a TNF-related signalling molecule mainly involved in ectodermal development. The clinicopathological appearance was associated with hypotrichosis, hypodontia, and a reduced number of eccrine glands, in addition to chronic rhinotracheitis and partial squamous metaplasia. Furthermore, for the first time in an ED1-deficient animal, a complete lack of respiratory mucous glands was observed. This suggests that the ED1 gene plays a role in the development of mucous glands, the absence of which resembles a feature of X-linked anhidrotic ectodermal dysplasia (ED1) in human patients. 相似文献