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71.
72.
The effects of doxorubicin (DOX) and DOX entrapped in standardized liposomes [mean diameter, 0.15 micron; (DOX-Lip)] on the survival of mice bearing liver metastases of mouse colon carcinoma CT38LD (C57BL/6J mice) or CT26 (BALB/c mice) were investigated. In vitro cultured CT38LD cells were more sensitive to DOX than CT26. In vivo DOX and DOX-Lip, administered iv 10 mg/kg weekly to a maximum of five injections, increased the life-spans of mice bearing CT38LD liver metastases 32% (P less than .05) and 64% (P less than .05), respectively. DOX-Lip was more effective than DOX in prolonging survival (P less than .05). Free DOX did not significantly increase the life-spans of mice bearing CT26 liver metastases (P greater than .5), whereas DOX-Lip increased the life-spans 35% (P less than .05). The results suggest that liposomal delivery of agents to the liver can enhance therapeutic activity and could be used as an arm of protocols for adjuvant therapy of liver metastases.  相似文献   
73.
Dually perfused human term placental lobules were exposed to forskolin, bovine parathyroid hormone (bPTH(1-34)) and human parathyroid hormone related-peptides, hPTHrP(1-34), hPTHrP(67-86)NH2 or PTHrP(107-138) for 15 min in the presence of 3-iso-butyl-1-methyl-xanthine (IBMX); control lobules were exposed to IBMX alone. Homogenates of these tissues were then assayed for cyclic adenosine 3',5'-monophosphate (cyclic AMP) and results normalized per mg of protein. Exposure to forskolin or bPTH(1-34) on both sides, and exposure to bPTH(1-34) at a concentration of 30 nM on the maternal side of the placenta or 120 nM on the fetal side of the placenta, significantly enhanced tissue cyclic AMP production compared with tissue exposed to IBMX alone. Exposure to hPTHrP(1-34), hPTHrP(67-86)NH2 and hPTHrP(107-138) at a concentration of 30 nM on both sides of the placenta had no significant effect upon tissue cyclic AMP production.  相似文献   
74.
青蒿素(1)是从青蒿(Artemisia annua)中分离得到的一个抗疟化合物。青蒿素的发现改变了以往抗疟药物均为含氮杂环化合物的格式,开创了一类以过氧化合物为特征的、对抗氯喹虫株有效的新型抗疟药物。七十年代青蒿素结构发表以来,国内外在化学、药理以及临床方面均进行了大量工作,成为当今抗疟药方面最活跃的一个研究课题。这里简要报道  相似文献   
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Endodontic literature suggests that only about 60% of endodontic therapy meets current technical standards and that general dentists may be making a significant contribution to this compromised care. If so, where in the continuum of dental education does this begin. This study evaluated the quality of obturation in mandibular molars provided on the one hand by 3rd year dental students instructed by endodontic faculty, and on the other hand by 4th year students instructed by general dentistry faculty, versus the quality of obturation achieved by endodontic residents who served as a control for both groups. Final radiographs were chosen from students in all three groups so that there were 22 samples per group. Three evaluators rank-ordered the radiographs. In order of excellence, the results were: (a) residents, (b) 3rd year students, and (c) 4th year students. There was no significant difference between the 3rd year students or the residents, only between residents and 4th year students (p < 0.05). The reasons for this outcome may range from dental school objectives to the private practice procedures of the general dentists who instructed the 4th year students.  相似文献   
77.
目的:构建重组人粒细胞-巨噬细胞集落刺激因子乳酸链球菌表达载体,为进一步研究人粒细胞-巨噬细胞集落刺激因子在乳链菌的表达及其治疗价值奠定基础。方法:实验于2005-04/2006-03在南方医科大学南方医院消化病研究所完成。①载体pNCSF的构建:将质粒集落刺激因子及含有P59启动子、USP45蛋白信号肽的pNBC1000质粒分别加入BamH Ⅰ和Pst Ⅰ进行双酶切,并用Apa Ⅰ、Sac Ⅰ进行双酶切鉴定,重组质粒命名为pNCSF。②SDGFP的TA克隆及载体pNCSFGFP的构建:将经过优化适合在乳链菌表达的人粒细胞-巨噬细胞集落刺激因子基因克隆于含有P59启动子、USP45蛋白信号肽的pNBC1000载体,得到重组质粒pNCSF;同时设计上下游引物经PCR扩增增强荧光表达蛋白(EGFP),TA克隆后经测序验证,再连接于pNCSF获得重组质粒pNCSFGFP。③载体pTRCSF、pTRCSFGFP的建立:将获得的pNCSF和pNCSFGFP进一步克隆于穿梭载体pTR1001c,以获得人粒细胞-巨噬细胞集落刺激因子乳链菌表达载体pTRCSF及pTRCSFGFP。结果:①载体pNCSF构建结果:酶切鉴定产物经1.0%的琼脂糖凝胶电泳后,发现有(含启动子P59、信号肽USP45、人粒细胞-巨噬细胞集落刺激因子)720bp的目的片段。②SDGFP的TA克隆及载体pNCSFEGFP的构建结果:SDGFP阳性克隆产物经EcoRⅠ酶切鉴定得到775bp目的片段。pNCSFEGFP酶切鉴定产物经1.0%的琼脂糖凝胶电泳后,发现有(含启动子P59、信号肽USP45、人粒细胞-巨噬细胞集落刺激因子、SDGFP)1495bp的目的片段。③穿梭质粒pTRCSF、pTRCSFGFP酶切鉴定结果:经Xba Ⅰ、Sac Ⅰ进行双酶切鉴定,分别得到约717bp、1492bp大小目的片段。结论:获得了人粒细胞-巨噬细胞集落刺激因子乳链菌表达载体pTRCSF及pTRCSFGFP,并经酶切鉴定和测序证实。  相似文献   
78.
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   
79.
激光治疗瘢痕的特征   总被引:3,自引:0,他引:3  
目的:介绍国内近20年来激光治疗瘢痕的临床研究概况,以期进一步了解激光治疗瘢痕的新进展。资料来源:应用计算机检索Pubmed和中国生物医学文献数据库1983/2006的相关文章,限定文章语言种类为英文和中文,检索词为“cicatrices(瘢痕),laser(激光)”。资料选择:对资料进行初审,选择临床试验研究文献查找全文。纳入标准:①有明确诊断标准。②随机对照实验或对照试验。有无随访,是否采用盲法不限制。③治疗组干预措施为激光或激光联合药物;对照组干预措施为曲安奈德、冷冻联合曲安奈德或不采用药物措施。排除标准:①非对照研究。②治疗组或对照组的干预措施不符合纳入标准。③机制研究。④重复研究。资料提炼:共收集到相关文献120篇,按上述标准纳入31篇,其余文献均被排除。资料综合:31篇文章中11篇为随机对照研究,10篇为对照研究,各研究的研究期为1~6个月。各研究所纳入的病例数量为10~50例。其中6个研究对比了激光与传统药物治疗瘢痕的疗效及安全性,2个研究进行了激光治疗瘢痕基础研究机制比较,10个研究观察了激光结合与单纯药物或单纯激光对瘢痕的疗效,4个研究比较了激光联合西药治疗瘢痕的疗效,2个研究观察了激光治疗瘢痕的副作用。7篇介绍国内或国外瘢痕治疗的研究情况。结论:激光治疗瘢痕的疗效可靠,具有副作用少,方法简单,安全性高,易被患者接受等优势。但由于激光治疗瘢痕还存在着一定的局限性,今后还需要在激光的穿透深度方面研究。  相似文献   
80.
Patient or user engagement with health and social care interventions is receiving increased attention and interest within practice settings and research. An English evaluation of three reablement services wished to include a measure of user‐engagement so as to explore its association with outcomes. As no measure of reablement engagement existed, an existing measure designed for use with physical rehabilitation patients (the Hopkins Rehabilitation Engagement Rating Scale) was adapted and its psychometric properties were tested. The adapted version was completed by reablement staff at the time an individual (n = 129) was discharged from one of the three reablement services. Outcomes data (Barthel Index, Nottingham Extended Activities of Daily Living Scale, General Health Questionnaire‐12) collected by the evaluation study at baseline (that is, at entry into reablement), discharge and 6 months postdischarge was used for some psychometric testing. Internal consistency and construct, predictive and discriminant validity were investigated. The adapted scale measured a single construct and had good internal consistency. Tests of predictive and discriminant validity were positive. Findings from a separate, small‐scale (n = 31) test–retest study offer an early indication that this is acceptable. There was, however, evidence of a ceiling effect and we consider ways this may be ameliorated. The Hopkins Rehabilitation Engagement Rating Scale – Reablement Version offers a means by which user engagement in reablement can be measured using a staff‐completed instrument. The association between engagement and reablement outcomes, revealed when testing for predictive validity, supports the argument for greater attention and investment in research on user engagement in reablement. More broadly, researching engagement within the context of an intervention often delivered by multiple practitioners offers the opportunity to further understand this concept which, in the past, has particularly focused on interventions delivered by a single practitioner. In addition, future work should include developing a companion measure completed by service users.  相似文献   
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