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11.
本文通过人精浆对PHA、ConA和PWM三种丝裂原诱导淋巴细胞转化反应的影响,间接了解HSP对T辅助、T抑制和B淋巴细胞功能的影响,结果发现不同浓度的精浆对三种丝裂原诱导的淋转反应均有明显抑制作用(P<0.05),且三种浓度HSP的抑制作用在无显著性差异(P>0.05);中浓度的精浆对PHA、ConA和PWM诱导转反应的抑制率分别为69.7、51.7和48.3%,说明精浆对机体的T辅助、T抑制性和B淋巴细胞功能均有明显的抑制作用。此外,还对精浆的免疫抑制作用机理和意义进行了讨论。  相似文献   
12.
特发性肌炎免疫机制研究及临床意义   总被引:4,自引:1,他引:3  
目的探讨多发性肌炎(PM)和皮肌炎(DM)患者骨胳肌组织损伤的免疫机制及临床意义。方法应用免疫荧光一步法和免疫组化SP法分析25例PM/DM肌组织中免疫球蛋白IgG、IgM、补体C3和浸润肌组织单核细胞的分布与定位。结果PM和DM肌组织中IgG、IgM、C3的阳性率分别为60%、33.3%、20%和70%、40%、50%,以IgG为主(P<0.05),分布于肌组织血管壁、肌膜和肌浆中,补体C3在DM血管壁的分布有统计学意义(P<0.05);80%PM和7O%DM肌组织有单核细胞浸润,PM以T淋巴细胞为主,Ia+活化TS细胞占多数,主要分布于肌内衣,DM以B淋巴细胞为主,多分布在肌柬衣血管周围。结论免疫反应在PM和DM发病机理中占重要地位,PM以T细胞介导的细胞毒作用为主,DM以体液免疫特别是补体介导的血管损害为主。  相似文献   
13.
实时定量RT-PCR的原理及方法   总被引:9,自引:0,他引:9  
实时定量RT-PCR广泛应用于定量检测mRAN表达水平,为基础研究、分子药物学和生物技术研究提供了一种有力的方法。该法具有易操作、高通量、敏感性高和特异性强的特点,随着新酶、新探针和新仪器的发展而得到快速的发展。本文将对实时定量RT-PCR的定量原理、仪器应用、探针种类的研究进展以及细胞因子mRNA表达水平检测上的应用作一综述。  相似文献   
14.
Humoral autoimmunity in pemphigus   总被引:1,自引:0,他引:1  
  相似文献   
15.
SSAHA: a fast search method for large DNA databases   总被引:17,自引:2,他引:17  
Ning Z  Cox AJ  Mullikin JC 《Genome research》2001,11(10):1725-1729
We describe an algorithm, SSAHA (Sequence Search and Alignment by Hashing Algorithm), for performing fast searches on databases containing multiple gigabases of DNA. Sequences in the database are preprocessed by breaking them into consecutive k-tuples of k contiguous bases and then using a hash table to store the position of each occurrence of each k-tuple. Searching for a query sequence in the database is done by obtaining from the hash table the "hits" for each k-tuple in the query sequence and then performing a sort on the results. We discuss the effect of the tuple length k on the search speed, memory usage, and sensitivity of the algorithm and present the results of computational experiments which show that SSAHA can be three to four orders of magnitude faster than BLAST or FASTA, while requiring less memory than suffix tree methods. The SSAHA algorithm is used for high-throughput single nucleotide polymorphism (SNP) detection and very large scale sequence assembly. Also, it provides Web-based sequence search facilities for Ensembl projects.  相似文献   
16.
BACKGROUND AND PURPOSE: Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens. This study was conducted to clarify the clinical features and outcome of patients with vancomycin-resistant enterococcal bacteremia. METHODS: Patients with vancomycin-resistant enterococcal bacteremia treated at a medical center in northern Taiwan between November 1998 and July 2006 were reviewed. Clinical and bacteriological characteristics of Enterococcus faecium and Enterococcus faecalis were compared. RESULTS: Twelve patients (6 males and 6 females) were included for analyses. The mean age was 69.3 years (range, 40 to 86 years), and 8 cases (66.7%) were older than 65 years. All patients had underlying disease. Two patients received total hip replacement before development of VRE bacteremia. Twelve patients had prior exposure to broad-spectrum antimicrobial therapy. Ten patients had prior intensive care unit stay and prior mechanical ventilation before VRE bacteremia. All of the patients (n = 12) had an intravascular catheter in place. Bacteremia was caused by E. faecalis in 4 patients and by E. faecium in eight. The portals of entry included urinary tract (8.3%), skin, soft tissue and bone (41.7%) and unknown sources (50.0%). E. faecium showed a higher rate of resistance to ampicillin and teicoplanin than E. faecalis (87.5% vs 0.0%, p=0.01). The 60-day mortality rate was higher in patients with E. faecium bacteremia than E. faecalis bacteremia (62.5% vs 0.0%), although statistical significance was not obtained (p=0.08). CONCLUSIONS: VRE bacteremia may have an impact on the mortality and morbidity of hospitalized patients. Patients with bacteremia caused by vancomycin-resistant E. faecium had a grave prognosis, especially immunosuppressed patients. The prudent use of antibiotics and strict enforcement of infection control may prevent further emergence and spread of VRE.  相似文献   
17.
目的 探讨吻合器痔上黏膜环切术(procedure for proplapse and hemorrhoids,PPH)的适应证、方法、临床应用价值.方法 总结41例PPH手术(Ⅰ组)和62例传统外剥内扎术(Milligan-Morgan手术)(Ⅱ组)临床资料,对手术时间、术后止痛次数、住院时间、术后并发症及住院费用等进行对比研究.结果 总的症状改善满意率分别为95%(Ⅰ组)及82%(Ⅱ组),除住院费用外,Ⅰ组其手术时间、术后止痛次数、住院时间明显优于Ⅱ组,并发症发生率除术后便血、早期大便失禁、早期排尿困难外,余无统计学意义.结论 PPH治疗Ⅲ°~Ⅳ°痔的近期疗效优于Milligan-Morgan手术,且具有安全、有效、手术时间短、住院时间少、恢复快等优点.  相似文献   
18.
Yue N  Nath R 《Medical physics》2002,29(6):1120-1129
Since the publication of the AAPM Task Group 43 report in 1995, Model 200 103Pd seed, which has been widely used in prostate seed implants and other brachytherapy procedures, has undergone some changes in its internal geometry resulting from the manufacturer's transition from lower specific activity reactor-produced 103Pd ("heavy seeds") to higher specific activity accelerator-produced radioactive material ("light seeds"). Based on previously reported theoretical calculations and measurements, the dose rate constants and the radial dose functions of the two types of seeds are nearly the same and have already been reported. In this work, the anisotropy function of the "light seed" was experimentally measured and an averaging method for the determination of the anisotropy constant from distance-dependent values of anisotropy factors is presented based upon the continuous low dose rate irradiation linear quadratic model for cell killing. The anisotropy function of Model 200 103Pd "light seeds" was measured in a Solid Water phantom using 1 X 1 x 1 mm micro LiF TLD chips at radial distances of 1, 2, 3, 4, 5, and 6 cm and at angles from 0 to 90 degrees with respect to the longitudinal axis of the seeds. At a radial distance of 1 cm, the measured anisotropy function of the 103Pd "light seed" is considerably lower than that of the 103Pd "heavy seed" reported in the TG 43 report. Our measured values at all radial distances are in excellent agreement with the results of a Monte Carlo simulation reported by Weaver, except for points along and near the seed longitudinal axis. The anisotropy constant of the 103Pd "light seed" was calculated using the linear quadratic biological model for cell killing in 30 clinical implants. For the model 200 "light seed," it has a value of 0.865. However, our biological model calculations lead us to conclude that if the anisotropy factors of an interstitial brachytherapy seed vary significantly over radial distances anisotropy constant should not be used as an approximation for anisotropy characteristics of a brachytherapy seed.  相似文献   
19.
目的探讨Fas蛋白在糖尿病大鼠脑缺血再灌注海马区神经元损伤中的表达及意义。方法健康雄性Wister大鼠60只,随机分为4组:①正常对照组,②假手术组,③脑缺血再灌注组(NIR),④糖尿病脑缺血再灌注组(DIR组);采用STZ诱导糖尿病和线栓法建立大脑中动脉闭塞(MCAO)模型,HE法观察海马CA1神经元缺失,用免疫组化方法检测Fas在糖尿病大鼠脑缺血再灌注海马神经元损伤中的表达。结果HE染色:正常对照与假手术组未见神经元缺失和细胞凋亡,DIR组与脑缺血再灌注组均见神经元缺失和神经细胞凋亡,而DIR组比脑缺血再灌注组神经元缺失严重(P<0.05)。正常对照与假手术组极少见Fas免疫染色阳性细胞,DIR组与脑缺血再灌注组明显见Fas免疫染色阳性细胞,且DIR组比脑缺血再灌注组多(P<0.05)。结论Fas介导的细胞凋亡可能是糖尿病脑缺血再灌注损伤后海马区神经元损伤的机制之一。  相似文献   
20.
以傅立叶频谱滤波为手段的振荡电位波形分离方法   总被引:1,自引:0,他引:1  
为克服传统方法(Calliper-square)和带通放大器在测量振荡电位(OPs)中的不足,应用计算机傅立叶频谱滤波技术,从ERG中分离出振荡电位波形。分离出的OPs能够摆脱a-波,b-波对它的影响而独立地表现出来,使得对OPs的测量变得直观、方便、准确,并把对ERG、OPs的研究,从时域分析扩展到频域分析。  相似文献   
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