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991.
本实验将赖型钩端螺旋体(简称钩体)DNA基因库的克隆pCX7制备成 ̄(32)P-重组DNA探针,对8个不同血清群的17株问号状钩体、双曲钩体PatocⅠ株以及细螺旋体3055株DNA进行打点杂交;同时用15种DNA片断进行限制性内切酶谱分析。结果表明,该重组DNA具有问号状钩体种(Species)特异性,但与不同问号状钩体之间的同源性程度有差别;限制性内切酶谱分析发现pCX7重组DNA片段长约1.7kb,具有1个Bg1Ⅱ识别位点和3个BstB1识别位点。 相似文献
992.
After eliminating confounding factors, the study was made on the relationship between height, collagen metabolism, hair zinc and excessive fluoride intake. 140 schoolchildren aged 12-13 years born and reared in endemic fluorosis areas were surveyed. The results were as follows: 1. The average height of children with dental fluorosis III degree (DF III degree) was appreciably smaller than that of children without dental fluorosis. Among children with excessive fluoride intake, a negative correlation between the height and fluoride level in staple foods was seen. 2. The more the fluoride ingested, the higher the urinary THP excreted, showing that fluoride intoxication interfered with the collagen metabolism. 3. Among children with excessive fluoride intake, the height showed negative correlation with urinary THP/Cr, suggesting that the effect of fluoride on collagen metabolism indicated the mechanism of height retardation. 4. As compared to control group with the excessive fluoride intake but without dental fluorosis group, there was a significant reduction in hair zinc in group with DF III degree, suggesting that the zinc in the body decreased because of zinc metabolism disturbance by excessive fluoride intake. But among cases with excessive fluoride intake, no appreciable correlation between hair zinc and height was found. Therefore, it could not be confirmed that the effect of fluoride on zinc metabolism affected the height development. 相似文献
993.
本文对精神分裂症患者用氯丙嗪治疗前后PAg(T)功能进行观察及BPRS评定,发现精分症患者PAg(T)功能明显高于对照组,用氯丙嗪治疗1个月后,BPRS评定分值下降,患者临床症状消除,而PAg(T)第一时相无变化,第二时相明显升高,说明氯丙嗪聚药物可促发血小板释放内源性致聚物质,同时也说明患者PAg(T)异常不仅仅是情绪应激所致,更重要的是血小板生理功能异常。 相似文献
994.
体外丹参、藻酸双酯钠对脑血栓形成患者红细胞与内皮细胞粘附的影响 总被引:3,自引:0,他引:3
丹参、藻酸双酯钠是临床治疗脑血管病的常用药。本研究发现,在体外流场中用丹参、藻酸双酯钠分别处理脑血栓形成病人的红细胞后,此红细胞与培养的人脉静脉内皮细胞的粘附数目明显减少、粘附强度明显减弱;而且,在临床常用剂量下藻酸双酯钠的这种抗粘附作用优于丹参。认为丹参、藻酸双酯钠的这种抗粘附作用可能是临床用以治疗脑血栓形成的一个重要机理。 相似文献
995.
血清肿瘤标志物联合检测在肺癌诊断中的应用 总被引:4,自引:0,他引:4
目的:探讨血清19片段角蛋白((2YFRA21-1)、神经元特异性烯醇化酶(NSE)、癌胚抗原((CEA)、β2微球蛋白(β2-MG)联合检测提高肺癌的阳性率,为临床提供早期诊断、治疗的依据。方法:采用电化学发光和免疫比浊法检测155例肺癌、72例肺良性疾病和50例正常人血清CYFRA21-1、NSE、CEA和β2-MG的水平。结果:肺癌4项标志物联合检测阳性率明显高于肺良性疾病组和健康人正常对照组,其中CYFRA21-1阳性率以鳞癌最高(77.7%),与其它型肺癌存在显著差异。NSE阳性率以小细胞性肺癌最高(78.4%),与其它型肺癌存在显著差异。结论:CYFRA21-1、NSE、CEA、β2-MG是诊断肺癌有价值的肿瘤标志物组合,有助于提高肺癌诊断的阳性率、特异性和准确性。 相似文献
996.
采用淀粉凝胶电泳法对云南水族人红细胞酸性磷酸多态分布状况进行了调查,检出EAPA型6例,EAPBA型45例,EAP55例。计算出基因频率分别为:EAP^A0.2689,EAP^B0.7311.EAP在云南水族人群中的DP值为0.5185。文中对EAP在不同人群中的分布进行了比较分析。 相似文献
997.
Identification of widespread Helicobacter hepaticus infection in feces in commercial mouse colonies by culture and PCR assay. 总被引:10,自引:1,他引:9 下载免费PDF全文
B Shames J G Fox F Dewhirst L Yan Z Shen N S Taylor 《Journal of clinical microbiology》1995,33(11):2968-2972
The identification of a new murine pathogen, Helicobacter hepaticus, and its association with chronic active hepatitis and liver tumors prompted an evaluation of the prevalence of H. hepaticus in commercially available mice. Of the 28 different strains or stocks, totaling 160 mice from four major commercial vendors, cultured for H. hepaticus, 100% of mice from two outbred strains from one vendor were infected with H. hepaticus, whereas 9 of 13 inbred mouse strains from another vendor were infected. This high prevalence of H. hepaticus established a need for a rapid and reproducible, noninvasive assay for the screening of colony-maintained mice being used for biomedical research. The culturing of fecal material by using 0.45-microns-pore- size filtration for H. hepaticus consistently yielded reproducible results but required extended periods of time. (1 to 3 weeks) to obtain a definitive answer. Although it is rapid, the use of a direct PCR-based detection assay with fecal specimens is restricted by inhibitory agents. to circumvent these inhibitory agents and to augment our H. hepaticus culture technique, we have developed a novel PCR system in which the bacteria are isolated from fecal material in the presence of polyvinylpyropyrollidone and lysed by treatment with Chelex 100. The PCR is performed with Tth polymerase supplemented with a polymerase enhancer. By this PCR method, 24 H. hepaticus culture-positive and 30 H. hepaticus culture-negative fecal samples were correctly identified. Moreover, two samples which were PCR positive and culture negative initially were positive by both methods upon retesting of fresh material. Southern blot hybridizations and sequencing of PCR products showed them to be H. hepaticus specific. A comparison of results obtained under identical conditions indicated a 100-fold increase in sensitivity with Tth polymerase over Taq polymerase. This PCR method can be used as a noninvasive means of rapidly screening large numbers of colony mice for H. hepaticus. 相似文献
998.
999.
Background
The efficacy of academic detailing in changing physicians' knowledge and practice has been the subject of many primary research publications and systematic reviews. However, there is little written about the features of academic detailing that physicians find valuable or that affect their use of it. The goal of our project was to explore family physicians' (FPs) perceptions of academic detailing and the factors that affect their use of it. 相似文献1000.
Barbara Resnick Denise Orwig Janet Yu-Yahiro William Hawkes Michelle Shardell J. Richard Hebel Sheryl Zimmerman Justine Golden Michele Werner Jay Magaziner 《Annals of behavioral medicine》2007,34(1):67-76
Background: Exercise is an important strategy with potential to improve recovery in older adults following a hip fracture.Purpose: The purpose of this study was to test the impact of a self-efficacy based intervention, the Exercise Plus Program, and the
different components of the intervention, on self-efficacy, outcome expectations, and exercise behavior among older women
post-hip fracture.Methods: Participants were randomized to one of four groups: exercise plus, exercise only, plus only (i.e., motivation), or routine
care. Data collection was done at baseline (within 22 days of fracture), 2, 6, and 12 months post-hip fracture.Results: A total of 209 women were recruited with an average age of 81.0 years (SD=6.9). The majority was White (97.1%), was widowed
(57.2%), and had a high school education (66.7%). Generalized Estimating Equations were used to perform repeated measures
analyses. No differences in trajectories of recovery were observed for self-efficacy or outcome expectations. A statistically
significant difference in the overall trajectory of time in exercise was seen (p<.001), with more time spent exercising in
all three treatment groups.Conclusions: The study demonstrated that it was possible to engage these women in a home-based exercise program and that the plus only,
exercise only, and the exercise plus groups all increased exercise.
Support for this project was provided by National Institute on Aging grants R37 AG09901, R01-AG18668, R01 AG17082, and the
Claude D. Pepper Older Americans Independence Center P60-AG12583. 相似文献