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81.
82.
青藏高原丽蝇科昆虫物种多样性初探   总被引:1,自引:0,他引:1  
本文从种数、特有物种和区系构成等角度分析了青藏高原丽蝇科昆虫的物种多样性。青藏高原已知丽蝇5亚科35属120种,占中国已知种数的44.28%,其中特有种55种,占该地区总种数的45.83%;区系构成以特有种、古北界 东洋界共同种及典型的东洋界种和古北界种为主,但澳洲界、新北界、非洲界和新热带界共同种也占一定比例。文中讨论了该地区特有种丰富的原因及地质历史环境对其的影响,分析了区系构成中各种区系成分的比例及形成原因。  相似文献   
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目前世界医药产业不断发展,逐渐形成了少数企业少数产品带来多数利润的发展新格局。我国医药产业与发达国家相比,整体处于大而不强的阶段。少数企业逐步壮大。多数药企研发投入严重不足。本文针对目前中国医药产业与研发的现状提出了自主研发"重磅炸弹"药物的方针。并从抓住创新时机、提高创新能力、走向国际竞争、培育创新环境四个方面给自主研发"重磅炸弹"药物给出建议。  相似文献   
85.
目的:探讨由肝硬化合并自发性细菌性腹膜炎(spontaneous bacterial peritonitis,SBP)患者血清中IL-10、IL-18及内毒素的水平及其临床意义.方法:采用ELISA方法检测各组血清IL-10、IL-18水平,采用偶氮显色基质法检测内毒素水平.结果:SBP患者血清中IL-10、IL-18及内毒素的水平明显高于正常对照组,P<0.05,SBP患者治疗后血清中IL-10、IL-18及内毒素的水平都明显降低,P<0.05.结论:检测血清中IL-10、IL-18及内毒素在肝硬化患者自发性细菌性腹膜炎中的诊断及预后中具有一定指导意义.  相似文献   
86.
上下视野空间选择性注意的ERP研究   总被引:6,自引:2,他引:6  
该文主要研究上、下视野空间选择性注意早期所诱发的ERP反应,探讨注意上、下视野视觉信息处理的特征与差别。10名被试的主要实验果为:1)对上、下视野的选择注意产生类似于注意左、右视野时P1、N1,P2的相对增强;2)偶极子定位显示,上、下视野刺激的早期注意反应(P1)以交叉方式投射到枕区,即下视野刺激的注意反应偏向枕区的背侧,而上视野刺激的注意反应偏向枕区的腹侧;3)上下视野的早期注意反应(P1)具  相似文献   
87.
A monospecific inhibitory antibody directed to phospholipase C (phosphoinositidase C) blocked the antiviral effect of human interferons alpha and beta when tested on human quiescent fibroblasts challenged with the vesicular stomatitis virus. This action was due to specific inhibition of polyphosphoinositide hydrolysis because (a) the F(ab)2 fragment of the antibody molecule was also inhibitory; (b) excess antibodies directed to phospholipase A2 and to a phosphatidylcholine-preferring phospholipase C did not have any inhibitory effect, and (c) the combination of 12-O-tetradecanoylphorbol-acetate and calcium ionophore A23187 had an interferon-like antiviral effect which was not influenced by the inhibitory anti-phospholipase C antibodies. To avoid an interferon-like effect due to induction of interferon by second messengers, Vero cells, which lack interferon biosynthesis, were also used. Liposomes containing inositol 1,4,5-triphosphate and 1-oleoyl-2-acetyl-rac-glycerol protected Vero cells against the infection with the vesicular stomatitis virus. These results taken together show that phosphoinositide-derived second messengers are involved in triggering the antiviral effect of interferons alpha and beta.  相似文献   
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To discover genes contributing to mental retardation in 3p- syndrome patients we have used in silico searches for neural genes in NCBI databases (dbEST and UniGene). An EST with strong homology to the rat CAM L1 gene subsequently mapped to 3p26 was used to isolate a full-length cDNA. Molecular analysis of this cDNA, referred to as CALL (cell adhesion L1-like), showed that it is encoded by a chromosome 3p26 locus and is a novel member of the L1 gene family of neural cell adhesion molecules. Multiple lines of evidence suggest CALL is likely the human ortholog of the murine gene CHL1: it is 84% identical on the protein level, has the same domain structure, same membrane topology, and a similar expression pattern. The orthology of CALL and CHL1 was confirmed by phylogenetic analysis. By in situ hybridization, CALL is shown to be expressed regionally in a timely fashion in the central nervous system, spinal cord, and peripheral nervous system during rat development. Northern analysis and EST representation reveal that it is expressed in the brain and also outside the nervous system in some adult human tissues and tumor cell lines. The cytoplasmic domain of CALL is conserved among other members of the L1 subfamily and features sequence motifs that may involve CALL in signal transduction pathways. Received: 14 April 1998 / Accepted: 18 June 1998  相似文献   
90.
We have previously reported (Hinescu & Popescu, 2005) the existence of interstitial Cajal-like cells (ICLC), by transmission electron microscopy, in human atrial myocardium. In the present study, ICLC were identified with non-conventional light microscopy (NCLM) on semi-thin sections stained with toluidine blue and immunohistochemistry (IHC) for CD117/c-kit, CD34, vimentin and other additional antigens for differential diagnosis. Quantitatively, on semi-thin sections, ICLC represent about 1-1.5% of the atrial myocardial volume (vs. approximately 45% working myocytes, approximately 2% endothelial cells, 3-4% for other interstitial cells, and the remaining percentage: extracellular matrix). Roughly, there is one ICLC for 8-10 working atrial myocytes in the intercellular space, beneath the epicardium, with a characteristic (pyriform, spindle or triangular) shape. These ICLC usually have 2-3 definitory processes, emerging from cell body, which usually embrace atrial myocytes (260 nm average distance plasmalemma/sarcolemma) or establish close contact with nerve fibers or capillaries (approximately 420 nm average distance to endothelial cells). Cell prolongations are characteristic: very thin (mean thickness = 0.15+/-0.1 microm), very long for a non-nervous cell (several tens of microm) and moniliform (uneven caliber). Stromal synapses between ICLC and other interstitial cells (macrophages) were found (e.g. in a multicontact type synapse, the average synaptic cleft was approximately 65 nm). Naturally, the usual cell organelles (mitochondria, smooth and rough endoplasmic reticulum, intermediate filaments) are relatively well developed. Caveolae were also visible on cell prolongations. No thick filaments were detected. IHC showed that ICLC were slightly and inconsistently positive for CD117/c-kit, variously co-expressed CD34 and EGF receptor, but appeared strongly positive for vimentin, along their prolongations. Some ICLC seemed positive for a-smooth muscle actin and tau protein, but were negative for nestin, desmin, CD13 and S-100. In conclusion, we provide further evidence of the existence of ICLC in human atrial myocardium, supporting the possible ICLC role in pacemaking, secretion (juxta- and/or paracrine), intercellular signaling (neurons and myocytes). For pathology, ICLC might as well be 'players' in arrhythmogenesis and atrial remodeling.  相似文献   
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