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排序方式: 共有1021条查询结果,搜索用时 15 毫秒
81.
目的检测骨髓增生异常综合征难治性贫血(MDS-RA)患者、慢性再生障碍性贫血患者、巨幼细胞性贫血及正常人血清乳酸脱氢酶(LDH),研究其对MDS预后判定及与再障鉴别的临床意义。方法采用国际血液学标准化委员会介绍的酶法。结果MDS-RA组与正常人组、再障组相比较血清LDH水平明显增高,差异有统计学意义(P〈0.01);再障组与正常人组相比较血清LDH水平无明显差异,差异无统计学意义(P〉0.05)巨幼细胞性贫血患者LDH水平亦明显增高。MDS.RA组中LDH明显增高组中位生存期明显短于LDH增高组,差异有统计学意义(P〈0.01)。结论血清LDH水平可作为MDS与再障鉴别诊断、MDS预后不良的指标,但尚须进一步与巨幼细胞性贫血鉴别。 相似文献
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Case studies covering carbonaceous nanomaterials, metal oxide and metal sulphate nanomaterials, amorphous silica and organic pigments were performed to assess the Decision-making framework for the grouping and testing of nanomaterials (DF4nanoGrouping). The usefulness of the DF4nanoGrouping for nanomaterial hazard assessment was confirmed. In two tiers that rely exclusively on non-animal test methods followed by a third tier, if necessary, in which data from rat short-term inhalation studies are evaluated, nanomaterials are assigned to one of four main groups (MGs). The DF4nanoGrouping proved efficient in sorting out nanomaterials that could undergo hazard assessment without further testing. These are soluble nanomaterials (MG1) whose further hazard assessment should rely on read-across to the dissolved materials, high aspect-ratio nanomaterials (MG2) which could be assessed according to their potential fibre toxicity and passive nanomaterials (MG3) that only elicit effects under pulmonary overload conditions. Thereby, the DF4nanoGrouping allows identifying active nanomaterials (MG4) that merit in-depth investigations, and it provides a solid rationale for their sub-grouping to specify the further information needs. Finally, the evaluated case study materials may be used as source nanomaterials in future read-across applications. Overall, the DF4nanoGrouping is a hazard assessment strategy that strictly uses animals as a last resort. 相似文献
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脑血管病发病机制及有效的治疗研究均需借助于理想的动物模型,动物模型观测的一个指标是测量不同时期的脑梗死面积;作者采用光化学法诱导的大鼠脑梗死模型,脑梗死灶应用扫描仪按比例扫描入计算机,利用灰度对比,计算梗死面积。1 方法 雄性SD大鼠20只,由第四军医大学实验动物研究中心提供,体重240±50g,鼠龄12周左右,二级动物。1模型制做方法:大鼠1%戊巴比妥钠(0.3ml/100g)腹腔注射麻醉,尾静脉注射CPD4后10min内,将鼠俯卧位于脑立体定位仪上,沿头颅正中线偏右切开头皮暴露颅骨前沿部位,在前囟门后1.8mm,正中线旁开约2mm,部位为上下肢皮… 相似文献
86.
Prasenjit Manna 《Toxicology and applied pharmacology》2010,244(2):114-283
Present study investigates the beneficial role of arjunolic acid (AA) against the alteration in the cytokine levels and simultaneous activation of oxidative stress responsive signaling pathways in spleen under hyperglycemic condition. Diabetes was induced by injection of streptozotocin (STZ) (at a dose of 70 mg/kg body weight, injected in the tail vain). STZ administration elevated the levels of IL-2 as well as IFN-γ and attenuated the level of TNF-α in the sera of diabetic animals. In addition, hyperglycemia is also associated with the increased production of intracellular reactive intermediates resulting with the elevation in lipid peroxidation, protein carbonylation and reduction in intracellular antioxidant defense. Investigating the oxidative stress responsive cell signaling pathways, increased expressions (immunoreactive concentrations) of phosphorylated p65 as well as its inhibitor protein phospho IκBα and phosphorylated mitogen activated protein kinases (MAPKs) have been observed in diabetic spleen tissue. Studies on isolated splenocytes revealed that hyperglycemia caused disruption of mitochondrial membrane potential, elevation in the concentration of cytosolic cytochrome c as well as activation of caspase 3 leading to apoptotic cell death. Histological examination revealed that diabetic induction depleted the white pulp scoring which is in agreement with the reduced immunological response. Treatment with AA prevented the hyperglycemia and its associated pathogenesis in spleen tissue. Results suggest that AA might act as an anti-diabetic and immunomodulatory agent against hyperglycemia. 相似文献
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Monoliths with chiral surface functionalization for enantioselective capillary electrochromatography
The state-of-the-art in CEC enantiomer separations with monolithic capillary columns is comprehensively reviewed. The various types of monolithic columns comprising in situ organic polymer monoliths, molecularly imprinted polymer (MIP) monoliths, silica monoliths and monoliths made from particles are discussed with a focus on materials’ synthesis, chemistry and properties as well as column aspects. Monolithic MIP-type porous layer open-tubular (PLOT) columns are treated herein as well. From this survey of the literature, the authors come to the conclusion that monolithic silica capillaries appear to become the preferred column type for CEC enantiomer separations of low-molecular drugs and other chiral pharmaceuticals or chemicals. 相似文献
90.
The present study was carried out to investigate the effects of catechin on adjuvant arthritis (AA) in the rat and its possible
mechanisms of action. AA was induced by metatarsal footpad injection with complete Freund’s adjuvant in male Sprague-Dawley
rats. The secondary inflammatory reaction was evaluated through assessment of hind paw swelling, polyarthritis index, and
pain response. Proliferation of synoviocytes and the activity of interleukin-1 were examined by 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium
bromide assay. Tumor necrosis factor-α, prostaglandin E2 (PGE2), and cyclic adenosine monophosphate levels in synoviocytes were measured by radioimmunoassay. The PGE2 receptor, EP2, was analyzed by Western blot analysis. Intragastric administration of catechin (60 and 120 mg/kg) significantly suppressed
secondary inflammatory paw swelling, pain response, and polyarthritis index. It also inhibited production of interleukin-1,
tumor necrosis factor-α, and PGE2 and increased cyclic adenosine monophosphate levels in rats with AA. In the immunoblot analysis, catechin could upregulate
expression of EP2 in the synoviocytes of rats with AA. The results showed that catechin reduced secondary inflammation in rats with AA; this
outcome reflects its ability to mediate cAMP levels, upregulate expression of EP2, and inhibit secretion of proinflammatory cytokines in rats with AA. 相似文献