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81.
Extracts of Tripterygium wilfordii Hook F.(TWHF ) are effective in traditional Chinesemedicine for treatment of autoimmune diseasessuch as rheumatoid arthritis, systemic lupus ery thematosus, nephritis and asthma [1, 2]. Trip tolide, a diterpenoid triepoxide, is derived fromTWHF and is responsible for most of the immuno suppressive and anti inflammatory effects ofTWHF. Triptolide has been shown to be effectivein the treatment of autoimmune diseases, …  相似文献   
82.
穿刺组织的微波快速碳蜡制片法朱新生,眭翔,王伯云(西安第四军医大学病理学教研室,西安710032)(北京医学高等专科学校病理学教研室,北京100071)我们试用了微波辐射技术将穿刺组织(小块组织)进行了快速碳蜡包埋制片和HE染色.初步取得了较满意的效...  相似文献   
83.
Synaptotagmin(Syt)constitutes a family of membrane-trafficking proteins,so far nearly 20 Syts have beendiscovered.Extensive work showed that synatotagmins were a potential Ca~(2+) sensor for regulated exocytosis.Thisstudy was to investigate the expression and location of synaptotagmin Ⅱ(Syt2)in RBL-2H3(RBL)and its role inregulating exocytosis of RBL.The expression of Syt2 in RBL was confirmed by Western blot.The recombinantexpression vector pEGFP-N1-Syt2 was constructed and transfected into RBL by electroporation,the stabletransfectant RBL-Syt2-S expressing fusion protein Syt2-EGFP were obtained and Syt2 was highly concentrated atplasma membrane with little detected in cytoplasm.To analyze the role of Syt2 during exocytosis of RBL,therelease of cathepsin D was assayed by immunoblotting.Compared with control,the release of cathepsin D byRBL-Syt2-S was markedly decreased.The results indicated that Syt2 played a negative regulation in exocytosis oflysosomes in RBL.Cellular & Molecular Immunology.2005;2(3):205-209.  相似文献   
84.
BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy.  相似文献   
85.
Bacterial sepsis is characterized by a systemic inflammatory state, with activation of numerous cell types. Phagocytes participate in this phenomenon by secreting various proinflammatory cytokines and enzymes. Matrix metalloproteinases (MMPs) such as gelatinases are produced by phagocytes and are thought to play an important role in processes of cell transmigration and tissue remodeling. In this work, we show that endotoxin (lipopolysaccharide [LPS]) and other inflammatory mediators, such as tumor necrosis factor (TNF), interleukin-8, and granulocyte colony-stimulating factor, induce a rapid (within 20 min) release of gelatinase-B (MMP-9) zymogen in whole human blood, as determined by gelatin zymography. The polymorphonuclear neutrophil was identified as the cell responsible for this rapid secretion, as a result of the release of preformed enzymes stored in granules. Normal human subjects given LPS intravenously showed a similar pattern of proMMP-9 secretion, with maximum plasma levels reached 1.5 to 3 h after LPS administration (P = 0.0009). Prior administration of TNF receptor:Fc, a potent TNF antagonist, to subjects given LPS, only partially blunted the release of proMMP-9 (P = 0.033). Ibuprofen, a cyclooxygenase inhibitor, did not alter this pattern of release. Increased levels of proMMP-9 and proMMP-2, as well as activated forms of MMP-9, were found in plasma from two patients with gram-negative sepsis. The levels of MMPs paralleled the severity of clinical condition and a marker of the severity of sepsis, plasma procalcitonin. These data indicate that MMPs are released in whole blood in response to various inflammatory mediators and that they could serve as sensitive and early markers for cell activation during the course of bacterial sepsis.  相似文献   
86.
87.
目的:观察肉瘤180(S180)移植瘤发展过程中血管生成及血管生成调节因子的变化,并对其调节机制进行探讨。 方法: 利用Km小鼠的S180移植瘤模型,采用FⅧ因子免疫组化染色检测肿瘤血管生成,ELISA和EIA法检测荷瘤鼠肿瘤组织和血浆中血管内皮生长因子(VEGF)和内皮抑制素(endostatin)水平,采用多元回归分析肿瘤组织微血管计数、血管形态与瘤重变化的关系。 结果: 随着荷瘤时间延长,肿瘤组织内微血管计数,瘤内血管相对总量增加,血管的相对面积增大(P<0.05);肿瘤组织匀浆中VEGF水平在荷瘤10 d、15 d均显著高于5 d组(P<0.05);endostatin在肿瘤匀浆和血浆中均在荷瘤15 d达到最高(P<0.05);V/E比值无显著变化;微血管计数、血管相对总面积与瘤重变化有相关性(P<0.01)。 结论: S180移植瘤病期发展中微血管数目增加,血管口径增大,且与瘤重变化呈正相关;肿瘤发展过程中肿瘤局部血管生成正调节因子逐渐增加,促进血管生成;肿瘤局部血管生成调节因子处于相对的平衡。  相似文献   
88.
In the study of bone and cartilage diseases in our laboratory, chondrocyte stereo-differentiation mod-el was cultured into cartilage tissue. The cultured cartilage tissue was closely similar to natural tissue inboth histological condition and biochemical metabolism. The model mimicked the chondrocyte differenti-ation and metabolism in vivo completely〔1〕. We studied some essential extracellular matrices, includingcollagen, proteoglycan(PG) and hyaluronic acid(HA) on the construction of grow…  相似文献   
89.
目的提高经典型苯丙酮尿症的产前诊断的成功率。方法在苯丙氨酸羟化酶(phenylalanine hydroxylase,PAH)基因附近选择了3个新的短串联重复序列(short tandem repeat,STR)位点(PAH26、PAH32和PAH9),进行扩增长度片段多态性分析,确定它们在中国人群的分布及在诊断中的应用价值。结果3个新的STR位点的多态信息含量分别为0.518(PAH26)、0.413(PAH32)和0.362(PAH9)。这3个位点之间,PAH9与第3内含子中的STR位点(TCTA)n之间存在连锁不平衡,其他位点组合不存在连锁不平衡。联合第3内含子中的STR位点(TCTA)n和2个新的位点,可以对家系中突变基因标记进行95%N断,并成功地用于4例产前诊断中。结论选择性地应用PAH基因中的3个STR位点组合,可以95%地区分经典型苯丙酮尿症家系中父母的两个基因,从而准确地进行快速产前诊断。  相似文献   
90.
探索重大突发公共卫生事件中以亚定点医院为代表的医疗管理模式。从上海新国际博览中心W1亚定点医院的实际运行情况出发,对其医疗供需、收治标准、运行效果、存在问题等逐一分析,结合本医疗队的经验,提出新的工作模式和管理思路。亚定点医院为普通型和有基础疾病的新冠病毒阳性感染者提供及时有效的救治,缓解了定点医院的运行压力,但也暴露出人员配置、信息化支撑、院感防控等方面的问题。采取“两级缓冲、双向转诊”的工作模式和“三个快、三个准、三个稳、三个全”的管理方案,可为患者提供及时、有效、适宜的医疗服务,缓解定点医院运行压力。  相似文献   
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