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目的:评价咪唑斯汀治疗慢性荨麻疹的疗效,探讨IL-4在慢性荨麻疹发病中的作用。方法:对32例慢性荨麻疹患用咪唑斯汀治疗,评价疗效,记录不良反应。同时用ELISA法检测慢性荨麻疹患治疗前后及正常人血清IL-4的水平。结果:治疗1、2wk后总有效率分别为62.5%、84.4%(P<0.01),不良反应3例。治疗前血清IL-4水平较正常人明显升高(P<0.01);治疗后IL-4水平下降(P<0.01),与正常人比较差异不甚明显(P>0.05)。结论:咪唑斯汀是一种有效、安全的治疗慢性荨麻疹的药物,能降低慢性荨麻疹患血清IL-4的水平。  相似文献   
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The series of vasicine (1) analogues, an alkaloid from Adhatoda vasica Nees., were synthesized with changes in A, B or C rings. Compounds 13-19 were evaluated for in vitro bronchodilatory activity using isolated guinea pig tracheal chain. Compounds 3-8 were also synthesized in good yields using microwave-mediated synthesis under solvent free conditions. Compounds 5 and 8 with seven-member C ring were more active than etofylline and caused 100% relaxation of both the histamine and acetycholine pre-contracted guinea pig tracheal chain. The structure-activity relationship studies showed that the quinazoline and oxo functionalities were essential for activity. The compounds without C ring and instead having aliphatic and phenyl substitutions in B ring showed relaxation against histamine pre-contracted tracheal chain only, 2-methyl substituted analogues, 12 and 13, being most active with 100% relaxation effect.  相似文献   
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目的:探讨黄芩苷、丹参酮ⅡA、三七皂苷R1对过氧化氢所致的大鼠海马神经元损伤的保护作用.方法:采用新生1d SD大鼠海马神经元原代培养,以H2O2(50μM)造成细胞损伤模型,将黄芩苷、丹参酮ⅡA、三七皂苷R1的高(20μg/ml)和低(0.2μg/ml)两个剂量加入到培养细胞液中.在4h时,检测细胞形态及释放出的LDH活性变化,观察到上述药物对海马神经元损伤的直接保护作用.结果:低剂量黄芩苷和三七皂苷R1与模型组比较,未见明显差异,三种组分高剂量和丹参酮ⅡA低剂量组与模型组比较,均有明显差异.结论:黄芩苷、丹参酮ⅡA、三七皂苷R1对过氧化氢所致的大鼠海马神经元损伤具有一定的保护作用.  相似文献   
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Data from many laboratory and clinical investigations indicate that CD34+ cells comprise approximately 1% of human bone marrow (BM) mononuclear cells, including the progenitor cells of all the lymphohematopoietic lineages and lymphohematopoietic stem cells (stem cells). Because stem cells are an important but rare cell type in the CD34+ cell population, investigators have subdivided the CD34+ cell population to further enrich stem cells. The CD34+/CD38- cell subset comprises less than 10% of human CD34+ adult BM cells (equivalent to < 0.1% of marrow mononuclear cells), lacks lineage (lin) antigens, contains cells with in vitro replating capacity, and is predicted to be highly enriched for stem cells. The present investigation tested whether the CD34+/CD38- subset of adult human marrow generates human hematopoiesis after transfer to preimmune fetal sheep. CD34+/ CD38- cells purified from marrow using immunomagnetic microspheres or fluorescence-activated cell sorting generated easily detectable, long- term, multilineage human hematopoiesis in the human-fetal sheep in vivo model. In contrast, transfer of CD34+/CD38+ cells to preimmune fetal sheep generated only short-term human hematopoiesis, possibly suggesting that the CD34+/CD38+ cell population contains relatively early multipotent hematopoletic progenitor cells, but not stem cells. This work extends the prior in vitro evidence that the earliest cells in fetal and adult human marrow lack CD38 expression. In summary, the CD34+/ CD38- cell population has a high capacity for long-term multilineage hematopoietic engraftment, suggesting the presence of stem cells in this minor adult human marrow cell subset.  相似文献   
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BACKGROUND & AIMS: Heat shock proteins (Hsps), induced by cell stress, are known to protect against cellular injury. Recent studies have indicated that Hsp60 expression, induced by exposure to water immersion stress, protects against pancreatitis induced by administration of supramaximal doses of cerulein in rats. However, the mechanisms responsible for this protection are not known. Methods: Rats were water-immersed for 3-12 hours. Pancreatitis was induced by cerulein administration. RESULTS: The results confirm that prior induction of Hsp60 expression by water-immersion stress significantly ameliorates the severity of cerulein-induced pancreatitis as judged by the markedly reduced degree of hyperamylasemia, pancreatic edema, and acinar cell necrosis. Water immersion also prevents the subcellular redistribution of cathepsin B from a lysosome-enriched fraction to a heavier, zymogen granule-enriched fraction that is known to occur in this model of pancreatitis. Intra-acinar cell activation of trypsinogen that occurs shortly after exposure to a supramaximally stimulating dose of cerulein both in vivo and in vitro is prevented by prior water-immersion stress and Hsp60 expression. The protection against pancreatitis that follows water-immersion stress is not caused by alterations of cholecystokinin receptors, because water immersion does not alter the typical biphasic amylase secretory response to stimulation with cerulein. CONCLUSIONS: Water-immersion stress induces Hsp60 expression, ameliorates cerulein-induced pancreatitis, and prevents intra-acinar cell activation of trypsinogen. We suggest that Hsp60 protects against cerulein-induced pancreatitis by preventing trypsinogen activation within acinar cells.  相似文献   
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BACKGROUND AND AIM: Recent studies have indicated that prior thermal stress causes upregulation of heat shock protein 70 (HSP70) expression in the pancreas and protects against secretagogue induced pancreatitis. The mechanisms responsible for the protective effect are not known. Similarly, the effects of prior non-thermal stress on HSP70 expression and pancreatitis are not known. The current studies were designed to specifically address these issues. METHODS: In the current studies pancreatitis was induced by administration of a supramaximally stimulating dose of caerulein 12 hours after thermal stress and 24 hours after non-thermal (that is, beta adrenergic stimulation) stress. RESULTS: Both thermal and non-thermal stresses caused pancreatic HSP70 levels to rise and resulted in increased expression of HSP70 in acinar cells. Both forms of stresses protected against caerulein induced pancreatitis and prevented the early intrapancreatic activation of trypsinogen which occurs in this model of pancreatitis. CONCLUSIONS: These results suggest that both thermal and non-thermal stresses protect against pancreatitis by preventing intrapancreatic digestive enzyme activation and that HSP70 may mediate this protective effect.  相似文献   
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