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51.
Summary— The aim of phase I studies per se is to explore the tolerance of new compounds which have demonstrated a certain level of activity in animals at sufficiently low non-toxic doses. In most cases, these studies are conducted in 2 steps in a limited number of healthy male volunteers: a single rising dose study followed by a repeated dose study in which the pharmacokinetic features of the drug are explored. In such a context, it would be quite presumptuous to ascertain the therapeutic efficacy of a drug from those initial human studies. At best, these trials can provide pharmacological and/or biological indications which are related to some degree to the expected efficacy of the drug: hypnotics, anticancer drugs, antibiotics, platelet antiaggregants, beta-blockers, etc. In these examples it is recommended to design controlled study protocols so as to better investigate these potentially interesting signs of activity. In the majority of cases, however (psychoactive drugs, analgesic, anti-inflammatory drugs, gastro-intestinal compounds), phase I studies will unfortunately not provide much information regarding the expected therapeutic activity.  相似文献   
52.
上海市0~6岁小儿佝偻病的现状调查   总被引:14,自引:0,他引:14  
目的:了解上海市小儿佝偻病的现状及影响因素。方法:2005年春季以整群和分层随机抽样法抽取上海市部分城区0~6岁小儿821名,采取问卷调查方法了解小儿的生活环境、饮食习惯、户外活动、营养状况、既往疾病史及母亲的妊娠情况等。佝偻病的诊断以1996年国家卫生部颁布的"婴幼儿佝偻病防治方案"为诊断标准。结果:取得完整有效资料769名,其中男童396名,女童373名;集居儿童456名,散居儿童313名。①小儿佝偻病患病率为17.3%(133/769),其中男童患病率为17.4%、女童为17.2%。②佝偻病与喂养方式(母乳喂养的患病率为13.0%、混合喂养的患病率为17.5%、人工喂养的患病率为25.2%)、鱼肝油添加(按时添加维生素D的患病率为13.5%、偶加或未加维生素D的患病率为32.5%)、居住环境(居住在市区的患病率为23.6%、居住在郊区的患病率为10.6%;集居儿童患病率为13.8%、散居儿童患病率为22.4%)、户外活动时间(经常户外活动的患病率为12.9%、偶尔户外活动的患病率为31.8%)、反复呼吸道感染(小儿有反复呼吸道感染的患病率为26.9%、无反复呼吸道感染的患病率为12.9%)、母孕期缺钙(母孕期有缺钙的患病率为33.2%、无缺钙的患病率为12.0%)等因素有关(P<0.01)。结论:上海市小儿佝偻病患病率有上升趋势。影响因素与城市环境污染、母乳喂养减少、年轻父母科学育儿知识缺乏等有关。  相似文献   
53.
目的:检测转化生长因子β1在腹膜透析大鼠腹膜内表达,并探讨其在腹膜纤维化中的意义。方法:实验于2005-06/2006-03在中南大学湘雅二医院肾内科实验室完成。①实验材料:雄性SD大鼠,体质量180~240g,由中南大学湘雅二医院动物实验中心提供。②实验方法:将28只大鼠按随机数字表随机分为4组,每组7只。正常对照组不予任何干预;生理盐水组腹腔注射20mL生理盐水;低糖透析液组腹腔注射20mL1.5%葡萄糖透析液;高糖透析液组腹腔注射20mL4.25%葡萄糖透析液,均为1次/d。4周后,向大鼠腹腔注射4.25%葡萄糖腹膜透析液20mL,4h后于大鼠右下腹缓慢插入带有多个侧孔的10号静脉留置针,缓慢低位引流腹透液,量取引流液。③实验评估:取大鼠壁层腹膜组织,以苏木素-伊红染色,镜下测量腹膜厚度,采用免疫组织化学方法检测大鼠腹膜中转化生长因子β1及纤连蛋白。结果:28只大鼠均进入结果分析。①高糖透析液组、低糖透析液组超滤量均明显低于正常对照组与生理盐水组,并且高糖透析液组超滤量明显少于低糖透析液组(P均<0.05)。②高糖透析液组腹膜明显增厚,表面粗糙,间皮细胞肿胀,脱落,间皮下有大量血管生成以及胶原纤维沉积,还可见单核细胞等炎症细胞浸润,与其他组比较,腹膜厚度明显增加(P<0.05)。③高糖透析液组转化生长因子β1、纤连蛋白表达量均明显高于其他组;低糖透析液组转化生长因子β1、纤连蛋白表达量均明显高于正常对照组与生理盐水组(P<0.05)。④大鼠腹膜组织转化生长因子β1蛋白与纤连蛋白表达量、腹膜厚度之间呈明显的正相关(r=0.86,0.83,P<0.05)。结论:葡萄糖透析液可诱导腹膜组织转化生长因子β1明显上调,腹膜转化生长因子β1高表达与腹膜透析腹膜纤维化密切相关。  相似文献   
54.
A sterilisable radiation probe of small dimensions was designed to locate the lesions at orthopaedic surgical sites according to the procedure of intraoperative bone scintigraphy. The probe has a collimated opening 2 mm in diameter. It is connected to a portable radioactivity counter which converts the disintegration rates detected at surgical sites into an acoustic signal that increases steeply with increasing disintegration rate. The acoustic signal enables the surgeons and isotope specialists to readily monitor radioactivity in the region of interest without attention being distracted from the surgical site. Dimethylaminodiphosphonate (designated SF44) was the osteotropic radiopharmaceutical chosen for carrying out intraoperative bone scintigraphy, since the available data show that this chemical increases the pathological: normal bone uptake ratio of the lesion by 25% compared to the usual diphosphonates. Forty-seven orthopaedic interventions were carried out according to the intraoperative bone scintigraphy procedure. They showed that this procedure facilitated the rapid location of the lesion, the objective termination of the operation, less frequently the reduction in dimension of the excised areas, and rarely the simplification of the surgical technique. Practice of intraoperative bone scintigraphy requires proper training and caution.  相似文献   
55.
Evidence based practice is essential to advanced practice nursing, enabling the delivery of quality care and improved patient outcomes. As the name suggests, it requires healthcare decisions to be based on the best available and current evidence. Advanced practice nurses need astute critical analysis skills to appraise the evolving literature, and require research skills to lead on scientific inquiry and develop the profession. Yet, advanced practice nurses may not recognize themselves as research leaders. Participation in a journal club can promote evidence-based practice, improve clinician's critical thinking skills, and expose members to different research methodologies, however, nurses continue to face barriers to participation in these clubs. Establishing a clinical-academic partnership appears to be both mutually beneficial for clinicians and academics and is a significant enabler in the sustainability and functioning of the club through sharing expertise and experience. A supportive workplace culture is favourable to research utilization and knowledge translation. This paper outlines the role, practicalities, challenges, and benefits of setting up a hybrid urology journal and research club for advanced practice nurses in a clinical-academic partnership.  相似文献   
56.
目的:观察视神经损伤动物模型在损伤后和不同时期视神经管减压后视觉诱发电位的变化,了解创伤性视神经损伤的手术时机与疗效的关系。方法:实验于2005-03/05在解放军南京军区南京总医院动物实验中心完成。①实验分组:30只新西兰白兔随机分为正常对照组、术后2d减压组、术后7d减压组、术后14d减压组、术后不减压组,每组6只。②造模:除正常对照组外,其余各组在视神经孔中塞入一细端为2mm直径的圆锥软硅胶,阻塞视神经孔,造成视神经的挤压伤。③指标检测:采用图形翻转视觉诱发电位检测损伤前、损伤后1h、减压前1h、减压后2周视功能变化,记录NPN曲线主波(P波)的绝对潜伏期、绝对波幅。正常对照组仅采集一组数据作为对照。结果:30只实验动物均进入结果分析。①正常对照组家兔图形翻转视觉诱发电位检查均引出典型NPN波型曲线,视神经挤压伤后1hNPN波形低阔扁平,P波潜伏期延长,波幅降低。②P波潜伏期:术后2d减压组减压后短于减压前[(71.25±8.51),(86.47±14.28)ms,P<0.05];术后7d减压组减压前后比较差异无显著性(P>0.05);术后14d减压组减压后明显长于减压前[(158.73±15.16),(116.35±17.13)ms,P<0.05]。术后2d减压组和术后7d减压组短于术后不减压组(P<0.01)。术后7,14d减压组和术后不减压组明显长于正常对照组(P<0.01)。③P波波幅:术后2d减压组减压后高于减压前[(5.25±0.78),(4.42±0.42)μV,P<0.05]。术后2d减压组减压后低于术后7d减压组、术后14d减压组(P<0.01),术后14d减压组低于术后7d减压组(P<0.05);术后7d减压组、术后14d减压组、术后不减压组低于正常对照组(P<0.01)。结论:神经元继发性损伤是视功能进行性下降的重要原因,视神经减压术有利于减轻视神经间接损伤,较早期(损伤后48h以内)减压可阻止轴突继发性损伤,避免视功能进一步下降,并在一定程度上逆转视功能的损害。  相似文献   
57.

Purpose

In this study, we estimate the impact of a recent relapse on physical and mental health in subjects with relapsing-remitting multiple sclerosis (RRMS) using validated patient-reported outcome (PRO) measures.

Methods

Subjects enrolled in the Comprehensive Longitudinal Investigation of MS at the Brigham and Women??s Hospital with RRMS were eligible for enrollment. Subjects with a clinical visit within 45?days of a relapse were identified and divided into groups based on whether the relapse occurred before (recent relapse) (n?=?59) or after the visit (pre-relapse) (n?=?31). A group of subjects with no relapses was also identified (remission) (n?=?336). PRO measures in these three groups were compared. All outcomes were compared using a t test and linear regression controlling for age, disease duration, sex, and EDSS.

Results

Subjects with a recent relapse had significantly worse functioning on several physical and mental health scales compared to subjects in remission even after adjusting for potential confounders. Subjects with a recent relapse also showed significant deterioration on PRO measures over 1?year compared to subjects in remission (P?<?0.05 for each comparison). Subjects in the pre-relapse group were not significantly different than subjects in remission.

Conclusions

Clinical relapses have a measurable effect on PRO in subjects with RRMS.  相似文献   
58.
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60.
ABSTRACT: Plasma levels of high density lipoprotein (HDL) cholesterol are strongly inversely correlated to the risk of atherosclerotic cardiovascular disease. A major recognized functional property of HDL particles is to elicit cholesterol efflux and consequently mediate reverse cholesterol transport (RCT). The recent introduction of a surrogate method aiming at determining specifically RCT from the macrophage compartment has facilitated research on the different components and pathways relevant for RCT. The current review provides a comprehensive overview of studies carried out on macrophage-specific RCT including a quick reference guide of available data. Knowledge and insights gained on the regulation of the RCT pathway are summarized. A discussion of methodological issues as well as of the respective relevance of specific pathways for RCT is also included.  相似文献   
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