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41.
Summary.  We have evaluated PCR–RFLP as a practical method for rapid typing of enteroviruses causing aseptic meningitis in Korea. Through blind examination of 80 clinical isolates from patients with aseptic meningitis, we have compared the results of conventional serotyping with PCR–RFLP based genotyping, which was developed for this study. Among the 80 case isolates, which had been previously typed by routine neutralization test, only 42 cases (52.5%) were matched with typing by PCR–RFLP. The result clearly demonstrated that the enterovirus serotype does not coincide with the genotype. Therefore, the classification of enteroviruses by genotyping with PCR–RFLP, although rapid and simple, may be complicated by regional or seasonal differences. However, the PCR–RFLP method developed in this study is applicable to the epidemiological study of enteroviruses when regional or seasonal differences exist, and is useful in identifying the source of an infection. Received August 6, 2001; accepted April 15, 2002 Published online July 10, 2002  相似文献   
42.
A rapid, selective and very sensitive ion-pairing reversed-phase HPLC method was developed for the simultaneous determination of trimebutine (TMB) and its major metabolite, N-monodesmethyltrimebutine (NDTMB), in rat and human plasma. Heptanesulfonate was employed as the ion-pairing agent and verapamil was used as the internal standard. The method involved the extraction with a n-hexane-isopropylalcohol (IPA) mixture (99:1, v/v) followed by back-extraction into 0.1 M hydrochloric acid and evaporation to dryness. HPLC analysis was carried out using a 4-microm particle size, C18-bonded silica column and water-sodium acetate-heptanesulfonate-acetonitrile as the mobile phase and UV detection at 267 nm. The chromatograms showed good resolution and sensitivity and no interference of plasma. The mean recoveries for human plasma were 95.4+/-3.1% for TMB and 89.4+/-4.1% for NDTMB. The detection limits of TMB and its metabolite, NDTMB, in human plasma were 1 and 5 ng/ml, respectively. The calibration curves were linear over the concentration range 10-5000 ng/ml for TMB and 25-25000 ng/ml for NDTMB with correlation coefficients greater than 0.999 and with within-day or between-day coefficients of variation not exceeding 9.4%. This assay procedure was applied to the study of metabolite pharmacokinetics of TMB in rat and the human.  相似文献   
43.
本文采用间接ELISA法检测了11株抗B-CLL患者IgM腹水和杂交瘤上清McAb的相对亲和力。结果提示,各株McAb结合抗原的相对亲和力不同。根据50%最大结合浓度分为两组。其中4株杂交瘤上清McAb与纯化腹水McAb测得结果基本吻合。实验结果为合理地选用这些单抗提供了重要依据。  相似文献   
44.
初三学生成就动机与学业成绩的关系研究   总被引:2,自引:1,他引:2  
编制中学生成就动机量表 ,考察 2 86名初三学生的成就动机状况。运用逐步回归分析探讨成就目标、归因方式、自我效能与学业成绩的关系 ,并对成就目标进行自我效能和归因方式的回归分析。结果表明 :影响初三学生学业成绩的主要成就动机因素是自我效能、表现目标、能力归因和掌握目标 ,努力归因、运气归因和自我效能是影响初三学生成就目标的主要因素 ,客观因素归因也会影响表现目标。对研究结果进行本土化思考 ,建构中学生成就动机的理想模型  相似文献   
45.
BACKGROUND: Like other herpes viruses, latent Epstein-Barr virus (EBV) infection can be reactivated to lytic replication. Reactivation can be achieved by treatment with various reagents, including tetradecanoyl phorbol acetate (TPA) and Ca2+ ionophores. Relatively little is known about the physiological factors related to reactivation of EBV. Previous studies have demonstrated that G0/G1 cell cycle arrest is associated with EBV activation, and that hypoxic conditions can induce cell cycle arrest. In the present study we investigated the effect of hypoxia on reactivation of EBV. OBJECTIVE AND METHODS: Hypoxic culture conditions were established and the expression of Zta protein and the number of EBV DNA copies were measured in B95-8 cells maintained under these conditions. RESULTS: Hypoxia treatment not only increased the expression of the EBV immediate-early protein Zta (which mediates the switch between the latent and lytic form of infection), but also increased the number of EBV DNA copies in B95-8 cells. CONCLUSIONS: EBV in latent infection can be activated to lytic infection by hypoxia treatment.  相似文献   
46.
目的: 观察非选择性一氧化氮合酶(NOS)抑制剂NG-硝基-L-精氨酸(L-NA)对急性肺损伤大鼠肺线粒体功能的影响,并探讨其改善急性肺损伤的作用机制。方法: 将SD大鼠随机分为空白对照组、急性肺损伤组、L-NA治疗组,采用舌静脉注射脂多糖(LPS)复制大鼠急性肺损伤模型,于大鼠急性肺损伤3h后给L-NA治疗3h,断头放血处死大鼠,迅速取出肺脏,匀浆器混匀后,低温差速离心法提取肺线粒体,测定线粒体总ATP酶、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、总一氧化氮合酶(T-NOS)、诱生型一氧化氮合酶(iNOS)、结构型一氧化氮合酶(cNOS)的活性,以及线粒体肿胀度、膜流动性和线粒体一氧化氮(NO)、丙二醛(MDA)含量;电镜观察大鼠肺线粒体超微结构的改变及治疗药对此改变的影响。结果: 在大鼠内毒素性急性肺损伤后,肺脏组织中线粒体表现为肿胀、膜流动性降低,线粒体中的T-NOS和iNOS活性显著升高,线粒体NO生成明显增加,而cNOS活性无明显变化;线粒体总ATP酶、SOD、GSH-Px活性均明显下降,线粒体MDA含量明显升高。急性肺损伤3h给予L-NA治疗3h,与急性肺损伤组相比,一氧化氮合酶活性有所改变,NO生成显著下降,总ATP酶、SOD、GSH-Px活性均显著升高,MDA含量下降。电镜结果显示内毒素性急性肺损伤后肺脏组织细胞水肿,线粒体肿胀、嵴断裂、溶解、消失;L-NA能改善内毒素性急性肺损伤引起的细胞水肿、线粒体肿胀和空泡化。结论: L-NA能明显抑制急性肺损伤后线粒体一氧化氮合酶活性,减少NO生成,改善线粒体能量供应,增加线粒体抗氧化作用,从而减轻急性肺损伤。  相似文献   
47.
Recent clinical trials showed that bortezomib, a novel proteasome inhibitor, had therapeutic activity in multiple myeloma. However, there was no data about the feasibility of bortezomib in Korean patients. We performed a pilot study of bortezomib in patients with relapsed or refractory myeloma (1.3 mg/m2 twice weekly for 2 week in a 3-week cycle). Seven patients were enrolled. The median age of patients was 59 yr. All patients previously received VAD (vincristine, doxorubicin and dexamethasone) and thalidomide chemotherapy. Three patients previously received alkylator-containing chemotherapy and 4 patients, autologous stem cell transplantation. Bortezomib monotherapy resulted in 3 partial remissions (43%), 3 no changes (43%) and 1 progressive disease (14%). One patient who had no response to bortezomib monotherapy experienced partial remission after addition of dexamethasone to bortezomib. The most common serious toxicity was thrombocytopenia (grade 3/4, 10 of 20 cycles (50%)) and grade 3 peripheral neuropathy was developed in 2 of 20 cycles (10%). Drug-related adverse event led to discontinuation of bortezomib in 1 patient. There was no treatment related mortality. Overall, bortezomib seems to be effective and feasible. Conduction of larger clinical studies on Korean patients is necessary to characterize clinical efficacy and safety of bortezomib more precisely.  相似文献   
48.
脑缺血性损伤早期小胶质细胞即被激活。激活的小胶质细胞既有细胞毒性又有神经营养作用。小胶质细胞行使免疫功能的信号转导受体之一是TLR4(toll-like receptor 4)。TLR4在脑内主要表达在小胶质细胞,是一种模式识别受体(pattern recognition receptor,PRR), 识别一些外源性和内源性的配体。最近的研究表明,TLR4信号通路在脑缺血再灌注损伤中起重要作用。TLR4通过激活小胶质细胞,大量表达炎症因子,加重脑缺血性损伤。  相似文献   
49.
A solid-phase blocking ELISA for detection of antibodies to Nipah virus   总被引:4,自引:0,他引:4  
A monoclonal antibody (MAb) based solid-phase blocking ELISA was developed for detection of antibodies to Nipah virus. The ELISA was designed to detect remaining antigens on the plate with anti-Nipah MAb conjugate after the reaction with sample serum, and enabled simple procedure, detection of neutralizing antibody to Nipah virus, and application of samples from different animal species. Forty of 200 swine reference sera examined were positive by the ELISA, of which thirty seven were found positive by serum neutralization test. Sera from a total of 131 fruit bats captured in Malaysia were also tested and all found negative by the both tests. It is considered that the solid-phase blocking ELISA can be used as a screening test for Nipah virus infection followed by the serum neutralization test as confirmatory test.  相似文献   
50.
人MASP1 N端片段原核表达载体的构建及其表达   总被引:1,自引:0,他引:1  
目的:在大肠杆菌中表达人甘露聚糖结合凝集素(MBL)相关丝氨酸蛋白酶1(MASP1)N端片段.方法:采用PCR技术从含人MASP1 cDNA的质粒pGEM-MASP1中扩增MASP1-N端基因片段,将其插入原核表达载体pGEX4T-1,转化BL21(DE3)感受态菌诱导表达MASP1-N端蛋白,通过GSTrap亲合层析柱纯化目的蛋白,以SDS-PAGE和Westernblot进行鉴定,并以ELISA分析了目的蛋白与重组MBL-CLR、重组MBL的结合活性.结果:从pGEM-MASP1中扩增得到约860 bp的基因片段,构建成重组载体经酶切出现约4 900 bp和860 bp片段,测序结果与预期的完全一致.纯化蛋白经SDS-PAGE可见Mr60000蛋白带,该蛋白可与抗GST抗体反应并能与重组人MBL-CLR、重组人MBL蛋白结合.结论:获得了表达人MASP1 N端片段的大肠杆菌菌株和重组人MASP1 N端片段/GST融合蛋白,为MASP1分子的进一步研究提供了条件.  相似文献   
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