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81.
近几年计算机网络信息技术飞速发展。为适应新的社会形势,向社会提供更优质高效的服务,我省疾病预防控制中心积极引进、开发多种管理信息系统,分别应用到传染病疫情监测、卫生检验、计划免疫、生物制品管理、行政办公等实际业务工作中,取得很好的成效。 相似文献
82.
杨红 《中华中西医学杂志》2007,5(6):1-1
目的评价米非司酮用于保守治疗异位妊娠的疗效。方法所选病例均住院治疗,予口服米非司酮50mg,每天两次,连服6天,定期复查B超和测定血p—HCG水平以观察疗效。结果68例异位妊娠患者的治疗,治愈46例,治愈率67.7%。结论米非司酮保守治疗异位妊娠疗效确切,副作用小。 相似文献
83.
J P Kinsella D R Gerstmann A K Gong A F Taylor R A deLemos 《Biology of the neonate》1991,60(5):283-291
We studied the hemodynamic effects of using natural surfactant in premature baboons with hyaline membrane disease (HMD). Study animals (n = 5) received a single dose of surfactant immediately after delivery and control animals (n = 8) did not. Using microspheres at 3, 8, and 23 h we found no significant differences in left ventricular output, effective systemic flow, systemic-to-pulmonary patent ductus arteriosus (PDA) shunting, or in cerebral or renal organ blood flow. However, both groups had large PDA shunts (fraction of LVO to lungs greater than 0.40-0.55 at 3 and 8 h) resulting in low systemic perfusion (less than 80 ml/min/kg). Single dose surfactant did not improve the myocardial dysfunction and low cerebral and renal blood flow which occur during treatment for HMD. 相似文献
84.
二步冷冻保存同种异体骨-ACL-骨移植后排斥反应的影响 总被引:3,自引:0,他引:3
目的 :探讨新鲜异体和二步冷冻保存同种异体骨 前交叉韧带 (ACL) 骨移植后排斥反应的差异。方法 :将 6 0只新西兰兔和 6 0只日本大耳兔分别随机分成自体骨 ACL 骨移植组、新鲜异体骨 ACL 骨移植组和二步冷冻保存同种异体骨 ACL 骨移植组 ,分别于术前及术后 1周、2周、3周、4周各采血 2ml测定血清中白细胞介素 2 (IL 2 )水平 ,术后 4周、12周切取移植关节 ,作苏木精 -伊红染色。结果 :光镜下检查显示 ,自体移植组和二步冷冻保存移植组均未见明显炎性细胞浸润 ,胶原排列规则 ,分化成熟。新鲜异体移植组有大量淋巴细胞浸润 ,其IL 2水平明显高于自体移植组和二步冷冻保存同种异体移植组且高于术前水平 (P <0 .0 1)。结论 :二步冷冻减轻了同种异体骨 ACL 骨移植后排斥反应 ,移植后其组织学改变同自体移植相似 相似文献
85.
激光光凝联合玻璃体腔注气治疗玻璃体切割术后再发黄斑孔 总被引:1,自引:0,他引:1
目的 探讨激光光凝联合玻璃体腔注气治疗玻璃体切割术后再发与未愈黄斑孔的疗效。方法 应用COHERENT Omni多波长激光光凝黄斑裂孔底部的视网膜色素上皮层。随后眼内注入20%C3F80.5~0.8ml并置换出玻璃体腔液体。治疗后每天坚持俯卧位。结果 19只眼中16只眼黄斑孔愈合,成功率为84.2%,视力提高15只眼,占78.9%,未出现严重的并发症。结论 应用激光光凝联合眼内注气治疗玻璃体切割术后再发与未愈黄斑孔具有方法简单、费用低、疗效确定、大部分患者无须住院等优点。 相似文献
86.
昆明种小鼠56只,在两个海拔高度上(300m和5000m)各分为两个组(对照组和复合组),分别给予相应的处理因素后,检测其血浆ANP水平和游泳时间。结果表明,小鼠在海拔5000m生活48h后,其血浆ANP较海拔300m小鼠降低52.87%,而其游泳时间则增长91.59%;在两个海拔高度上,复合组血浆ANP都较对照组降低,而游泳时间都长于对照组.提示复合方案提高高原劳动能力的机理,可能与降低体内血浆ANP水平有关。 相似文献
87.
Is neurogenesis reparative after status epilepticus? 总被引:1,自引:0,他引:1
88.
Jeffrey E. Fletcher Marcy Hubert Steven J. Wieland Qi-Hua Gong Ming-Shi Jiang 《Toxicon》1996,34(11-12)
Myonecrosis induced in vivo by cardiotoxin, melittin, and Asp49 and Lys49 phospholipase A2 (PLA2) myotoxins involves rapid lysis of the sarcolemma, myofibril clumping, and hypercontraction of sarcomeres. In contrast, skeletal muscle necrosis induced by crotamine and myotoxin a is much slower, consisting of mitochondrial and sarcoplasmic reticulum swelling, myofibril degeneration, and lack of sarcolemma or transverse tubule damage. The mechanisms contributing to the myonecrosis induced by these peptides were evaluated. Two cardiotoxins and two Lys49 PLA2 myotoxins lysed primary cultures of human skeletal muscle within 24 hr at a concentration of 0.25 μM, while melittin, crotamine, and myotoxin a, and an Asp49 PLA2 myotoxin were non-cytolytic at concentrations up to 5.0 μM, suggesting that cytolysis is not a good measure of myotoxicity. Crotamine and the Lys49 PLA2 myotoxin altered Ca2+ ion flux in human heavy sarcoplasmic reticulum by opening the ryanodine receptor. Whole-cell patch-clamp studies demonstrated that administrating crotamine intracellularly increased Na+ currents. Free fatty acids, liberated by activation of tissue phospholipase C or by the PLA2 activity of the myotoxins, were monitored for crotamine, myotoxin a and a Lys49 PLA2 myotoxin in cell cultures in which the lipids had been radiolabeled. Only the Lys49 myotoxin produced significant amounts of fatty acid in cell cultures, supporting a potential role for fatty acid production only in the mechanism of sarcolemma-destroying myotoxins. These findings, coupled with those in the literature, support a hypothesis in which the myotoxins and/or products of lipase activity (e.g. fatty acids) are acting at a site existing on both the Na+ channel and a protein involved in Ca2+ release and probably serving a modulatory function for ion regulation. Based on the similarities in mechanisms between the toxins and fatty acids, the most likely site would be a fatty acid binding site on the protein (either similar to that on fatty acid binding proteins, or an acylated cysteine residue) or in the membrane. 相似文献
89.
Proteolytic Processing Mechanisms in the Biosynthesis of Neuroendocrine Peptides: The Subtilisin-like Proprotein Convertases 总被引:1,自引:0,他引:1
Yves Rouill Stephen J. Duguay Kaare Lund Machi Furuta Qiuming Gong Gregory Lipkind Anthony A. Oliva Jr. Shu Jin Chan Donald F. Steiner 《Frontiers in neuroendocrinology》1995,16(4)
The recent discovery of a novel family of precursor processing endoproteases has greatly accelerated progress in understanding the complex mechanisms underlying the maturation of prohormones, neuropeptides, and many other precursor-derived proteins. At least six members of this family have been found thus far in mammalian species, several having alternatively spliced isoforms, and related enzymes have been identified in many invertebrates, including molluscs, insects, nematodes, and coelenterates. The proprotein convertases are all dependent on calcium for activity and all possess highly conserved subtilisin-like domains with the characteristic catalytic triad of this serine protease (ordered Asp, His, and Ser along the polypeptide chain). Two members of this family, PC2(SPC2) and PC1/PC3(SPC3), appear to play a preeminent role in neuroendocrine precursor processing. Both convertases are expressed only in the brain and in the extended neuroendocrine system, while another important family member—furin/PACE (SPC1)—is expressed more ubiquitously, in almost all tissues, and at high levels in liver. SPC2 and SPC3 exhibit acidic pH optima and other properties which enhance their activity in the acidic, calcium-enriched environment of the dense-core secretory granules of the regulated pathway in neuroendocrine cells, while furin has a neutral pH optimum and is localized predominantly to the trans Golgi network where it is retained by a C-terminal transmembrane domain. Furin processes a wide variety of precursors in the constitutive pathway, such as those of growth factors, receptors, coagulation factors, and viral glycoproteins. Recent findings on the processing of proopiomelanocortin, proinsulin, proglucagon, and several other neuroendocrine precursors by SPC2 and SPC3 are discussed, along with information on the structure, properties, evolution, developmental expression, and regulation or the convertases. An inherited defect in the fat/fat mouse which affects the processing of proinsulin, and probably also many other prohormones, due to a point mutation in carboxypeptidase E has recently been identified and has begun to provide new insights into the functional integration of the individual processing steps. 相似文献
90.
特发性肌炎免疫机制研究及临床意义 总被引:4,自引:1,他引:3
目的探讨多发性肌炎(PM)和皮肌炎(DM)患者骨胳肌组织损伤的免疫机制及临床意义。方法应用免疫荧光一步法和免疫组化SP法分析25例PM/DM肌组织中免疫球蛋白IgG、IgM、补体C3和浸润肌组织单核细胞的分布与定位。结果PM和DM肌组织中IgG、IgM、C3的阳性率分别为60%、33.3%、20%和70%、40%、50%,以IgG为主(P<0.05),分布于肌组织血管壁、肌膜和肌浆中,补体C3在DM血管壁的分布有统计学意义(P<0.05);80%PM和7O%DM肌组织有单核细胞浸润,PM以T淋巴细胞为主,Ia+活化TS细胞占多数,主要分布于肌内衣,DM以B淋巴细胞为主,多分布在肌柬衣血管周围。结论免疫反应在PM和DM发病机理中占重要地位,PM以T细胞介导的细胞毒作用为主,DM以体液免疫特别是补体介导的血管损害为主。 相似文献