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111.
应用低严格度—单引物聚合酶链反应对问号钩体中国参考株的… 总被引:1,自引:0,他引:1
G1、G2引物是对问号钩体具有特异性引物。分别用G1或G2单引物对问号钩体中国参考株进行前4个低严格度循环的PCR扩增,扩增带谱显示赖型、犬型、致热型、秋季型、澳洲型、临海型、乌尔夫型、溶血型为一类,而爪哇型、拜伦型、波摩那型、七日热型、巴叶赞型塔拉索夫型、曼耗Ⅱ型是不与以上赖型等血清型本为一类,双曲钩体atoc型及伊利尼细丝体伊利尼型的扩增带谱与问号钩体截然不同。应用苯酚法提取的高纯度钩体DNA 相似文献
112.
Fictive oesophageal peristalsis evoked by activation of muscarinic acetylcholine receptors in rat nucleus tractus solitarii 总被引:1,自引:0,他引:1
The aim of the present study was to determine if muscarinic acetylcholine receptor-mediated peristaltic rhythmogenesis in the rat oesophagus is a central motor program that can be generated without peripheral sensory support. In anaesthetized male Sprague-Dawley rats, pressure-ejection of glutamate (10–20 pmol) and muscarine (5–10 pmol) in the subnucleus centralis of the nucleus tractus solitarii (NTSC ) evoked monophasic pressure waves and rhythmic oesophageal peristalsis, respectively, but did not change mean arterial blood pressure or respiration. Application of muscarine (50–100 pmol) to the NTS extraventricular surface evoked rhythmic multi-unit burst discharges in the compact formation of the nucleus ambiguus (AMBC ) that led to oesophageal peristalsis in a phase-locked manner. Evoked rhythmic AMBC activity persisted during neuromuscular blockade with curare, although the peak frequency of individual bursts was decreased. In a brainstem slice preparation, intracellular and whole cell patch recordings from AMBC neurones during focal stimulation of the NTSC region with muscarine revealed rhythmic depolarizing waves that showed a pattern similar to that of rhythmic oesophageal peristalsis. The present findings support the concept that medullary circuits comprising premotor neurones of the NTSC are intrinsically capable of generating rhythmic oesophagomotor output, but are subject to a powerful modulation by peripheral sensory feedback. 相似文献
113.
目前,国内同行对细菌引起病人医院感染的研究比较深入广泛。为了解医务人员自身感染原因及对工作和病人的影响,对本院医务人员自身感染的情况进行回顾性调查,将感染状况分析如下。 相似文献
114.
Yan Wang Xuesong Zhang Songhua Xiao Ning Lu Zheng Wang Mi Zhou 《Journal of orthopaedic surgery and research》2006,1(1):13-7
Objectives
To investigate clinical effects and manual operational point of Bryan cervical disc prosthesis in Chinese, to observe the stability and range of movement (ROM) post-operatively. 相似文献115.
Matteo Brunelli John N Eble Shaobo Zhang Guido Martignoni Liang Cheng 《Modern pathology》2003,16(10):1053-1059
It has been suggested that gains of chromosomes 7 and 17 and loss of Y occur in renal papillary adenoma and that progression to papillary renal cell carcinoma is marked by gains of additional chromosomes, most frequently 12, 16, and 20. Previous studies have included very few lesions of <5 mm in diameter, a requirement of the present definition of papillary adenoma. Ten papillary adenomas (ranging from 1 to 5 mm in diameter) from autopsy material and 10 surgically resected papillary renal cell carcinomas were studied with fluorescence in situ hybridization in paraffin sections using centromeric probes for chromosomes 7, 12, 16, 17, 20, and Y diluted 1:100 with tDenHyb1 buffer. The signals in 50 to 150 nuclei were counted in each tumor. Controls for all the probes were normal renal tissues from the same patients. Three or more signals per nucleus were frequently observed in papillary adenomas: chromosome 7 (range, 10 to 50%; > or = 30% in 9 of 10), 17 (range, 10 to 47%; > or = 30% in 7), 16 (range, 1 to 63%; > or = 10% in 5), 12 (range, 0 to 32%; > or =10% in 4), and 20 (range, 5 to 49%; > or = 10% in 5). Loss of the Y chromosome was observed in 80 to 90% of nuclei in 9 adenomas from males. Three or more signals were frequent in papillary renal cell carcinomas: chromosome 7 (range, 32 to 63%; > or =30% in 10 of 10), 17 (range, 28 to 61%; > or = 30% in 7), 16 (range, 0 to 45%; > or = 10% in 6), 12 (range, 1 to 37, > or = 10% in 5), 20 (range, 2 to 44%; > or = 10% in 4). No signal for Y was observed in 12 to 88% (> or = 81% in 6) of nuclei in 7 carcinomas from males. Statistical analysis showed no difference between adenomas and carcinomas. Gains of chromosomes 7, 17, 16, 12, and 20 and loss of the Y chromosome occur early in the evolution of papillary renal cell neoplasia in tumors that are only a few millimeters in diameter. Progressive gains of these chromosomes do not appear to correlate with the transition from adenoma to carcinoma. 相似文献
116.
报告全胃切除ρ形空肠代胃治疗胃癌64例。术后无吻合口瘘与手术死亡,无返流性食管炎和倾倒综合征,生存质量满意。术后1、3、5年生存率分别为71.8%、42.2%和34.4%。本组结果表明:此种改良后的ρ形空肠代胃、空肠原位间置术式,安全、简便、省时,使常见的手术并发症和远期后遗症均可得到较好预防和纠正,术后生存质量高,是一种满意的代胃术。 相似文献
117.
Summary In this study the technique of labelling the cell membrane with DPH fluorescence polarization was used to observe the membrane
fluidity of B lymphocytic cell lines and tonsillar cells from healthy persons; the modulation effect on membrane-fluidity
induced by McAbs against isotypic and idiotypic determinants of IgM from patients with leukemia was studied as well. The expression
of the corresponding isotypic and idiotypic determinants of IgM on the cell membrane was determined. The results show that
the membrane fluidity of leukemic cell lines is remarkably higher than that of tonsillar cells from healthy persons, and McAbs
against isotypic determinants of leukemic IgM can enhance the membrane fluidity of all kinds of cells mentioned above. However,
the anti-idiotypic monoclonal antibody increased only the membrane fluidity of leukemic cell lines. These results indicated
that there was a close relationship between the effect of McAbs on cell membrane fluidity and the expression of corresponding
isotypic and idiotypic determinants of IgM on the cell membrane. 相似文献
118.
The precision of renal mean transit time (MTT) measurements by 99Tcm-DTPA scintigraphy was studied by a Monte Carlo procedure. Data were obtained from twenty mild essential hypertensives with normal renal function. An ensemble of equivalent data sequences was constructed for each renal time-activity curve (TAC), assuming the dominant noise in the data to be Poisson in character. TACS were deconvolved by the matrix method and MTT was inferred from retention functions by a procedure entailing a nonlinear least-squares minimization. For every ensemble of data sequences a distribution of MTTs was generated. The population-averaged coefficients of variation for these distributions were 1.6% and 2.6%, for whole-kidney and cortical data, respectively. We conclude that the precision of MTT determination from clinical data is comparable to that from simulated data. MTT measurements may be useful for detecting functional changes in individual kidneys following an intervention such as angiotensin-converting-enzyme inhibition. 相似文献
119.
Three representative types of houses in Beijing were selected and, in each type, smoking and nonsmoking households were compared, IP, RP, and CO concentrations in the living room and kitchen were monitored during each season, and the level of COHb in the heads of the households were measured. The study showed that indoor air pollution was rather severe, especially during winter, when particulate concentrations markedly exceeded the standard and CO concentration was as high as 47 ppm. Indoor air pollution was closely related to the type of house, particularly to the mode of heating. In houses, of the same type, pollution improved greatly after central heating facilities were installed. Analysis of 30 elements revealed that pollution was typically caused by coal burning, aggravated by dusty wind, but high indoor Pb levels were probably due to the use of LPG for cooking. In our study the effect of cigarette smoking was sometimes masked by the severe indoor pollution. 相似文献
120.
CT measurement of metrizamide myelography of 100 normal adults 总被引:1,自引:0,他引:1