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91.
假性甲状旁腺功能减退症1例 总被引:1,自引:0,他引:1
患儿,男,5个月,因呼吸不畅5d,门诊以先天性喉喘鸣收入院。5d前出现呼吸不畅,咽喉部有痰鸣,故入院。查体:圆脸、下颏短,前囟2.5cm×2.5cm,平坦,枕秃( ),乒乓球感( ),咽稍红,双肺呼吸音可闻及喉鸣音,未闻及干湿啰性音,心脏、腹部及神经系统未见异常。血钙1.75mmol/L,血磷1.81mmol 相似文献
92.
病毒感染与急性弛缓性瘫痪 总被引:16,自引:0,他引:16
吴沪生 《中国实用儿科杂志》2007,22(7):484-485
急性弛缓性瘫痪(又称急性弛缓性麻痹,acute flaccidparalysis AFP)不是单一的疾病,是以急性起病、肌张力减弱、肌力下降和腱反射减弱或消失为主要特征的一组综合征。从传染病的监测与控制工作的角度认识,其监测病例的意义尚包括所有15岁以下出现AFP症状的病例,任何年龄临床诊断为脊髓灰质炎(脊灰)的病例均作为AFP病例。中国1994年报告最后1例本土脊灰野病毒病例。2000-10中国所在世界卫生组织(WHO)西太平洋区宣布我国为无脊灰地区,标志我国进入无脊灰状态。随着全球消灭脊灰的进展,今后仍需重视AFP的诊断与鉴别诊断。AFP可见于不同… 相似文献
93.
目的检测成牙本质细胞中上游刺激因子1(upstream stimulatory factor 1,USF1)对骨桥素表达的影响。方法培养成牙本质细胞MDPC-23,稳定转染PCMV-USF1和酸性-USF(A-USF)质粒,提取总RNA,半定量反转录聚合酶链反应检测骨桥素的表达水平,并对结果进行统计学分析。结果筛选出稳定转染USF1和A-USF的抗性克隆,USF1、A-USF转染组和对照组骨桥素相对灰度比值分别为:60.33%±4.51%、229.33%±7.09%、110.00%±15.62%,转染组与对照组差异有统计学意义(P〈0.01)。结论USF1可调控成牙本质细胞骨桥素mRNA转录,该作用被A-USF部分阻断。 相似文献
94.
Han B Jaurequi J Tang BW Nimni ME 《Journal of biomedical materials research. Part A》2003,65(1):118-124
While attempting to find a suitable crosslinking reagent for biopolymers, a naturally occurring proanthocyanidin (PA) obtained from grape seeds was selected to fix biological tissues. The cytotoxicity and crosslinking rate, reflected by the in vitro and in vivo degradation of fixed matrices has been studied. The shrinkage temperature of the fixed bovine pericardium increased from 66 to 86 degrees C. A cytotoxicity assay using fibroblast cultures revealed that PA is approximately 120 times less toxic than glutaraldehyde (GA), a currently used tissue stabilizer. In vitro degradation studies showed that fixed tissue was resistant to digestion by bacterial collagenase. Crosslinks between PA and tissues can be stabilized by decreasing the dielectric constant of the solution during storage. After subcutaneous implantation for periods ranging between 3 and 6 weeks, we found no apparent degradation of the GA- or PA-fixed tissues, whereas fresh tissue controls rapidly disintegrated. Beyond 6 weeks PA crosslinks began to degrade. More fibroblasts migrated and proliferated inside the PA-fixed implants compared with GA counterparts. Tissues crosslinked with PA manifested an enhanced collagen expression and deposition and did not calcify after implantation. GA, on the other hand, even after thorough rinsing continued to be cytotoxic, inhibited collagen synthesis and encouraged dystrophic calcification. Collagen matrices crosslinked with PA are expected to be of value in the design of matrices that will encourage cell ingrowth and proliferation, which are temporary in nature, and that are intended to regenerate or replace missing tissues, which can delay the biogradation of collagen. As such they should be of significant value in the emerging field of tissue engineering. 相似文献
95.
Conclusions NT antibodies to LI virus were found in the sera of Swedish cows from many parts of the country although only exceptionally in the north. The prevalence of positive specimens increased markedly towards the southeast. This geographic distribution apparently fits well with the occurrence of ticks in the country. An analysis, now in progress, of RSSE-LI antibodies in human cases of meningoencephalomyelitis seems to indicate a closely similar distribution of the human RSSE infections. It is thus obvious that the screening of cow sera for LI antibodies provides reliable information as to endemic regions of RSSE-LI-like viruses. There was nothing to suggest that nonspecific reactions occurred or impaired the results; in fact the very uneven geographic distribution of positive specimens, of high as well as low titers, should argue for specificity of the reaction.Aided by a grant from the Swedish National Association against Poliomyelitis.The skilful technical assistance of MissSiri Austrin, MissIngrid Lövhvist, MissBrita Gustafson and Mr.Nils Lundh is gratefully acknowledged. 相似文献
96.
97.
目的研究1例17α-羟化酶/17,20-裂解酶部分性联合缺陷症患者CYP17A1基因突变特点,并结合患者的临床表现与基因突变类型初步探讨P450C17酶蛋白的结构与功能的关系。方法收集1例17α-羟化酶/17,20-裂解酶部分性联合缺陷症患者的临床资料及其亲属血标本,提取基因组DNA,设计7对引物扩增CYP17A1基因的8个外显子及外显子与内含子的连接区域,琼脂糖凝胶电泳鉴定PCR产物,产物胶回收后直接做为DNA双链模板测序。DNA双链模板不一致的PCR产物经克隆后测序。测序结果在核苷酸序列数据库进行比较分析。结果患者CYP17A1基因突变检测结果为5994-5995delAT/7541C>T复合杂合子。这两种突变均未见报道。推测5994-5995delAT导致I259H,274X,突变形成的截短蛋白质缺少血红素结合区域,因此是没有功能的;而通过人类P450C17酶计算机模型分析显示7541C>T导致的A398V远离酶的活性中心,推测突变可能使酶的活性减弱,而不是完全地丧失。患者临床表现为有自发不规则月经及轻度高血压、低血钾,结合激素测定结果提示肾上腺和性腺保留部分功能。因而患者的基因型与其临床表型是一致的。结论应进行突变P450C17酶的功能学研究来进一步明确结构改变对功能的影响。 相似文献
98.
当归注射液对脑血栓患者花生四烯酸代谢产物和氧自由基水平的影响 总被引:4,自引:0,他引:4
目的 :了解当归注射液改善脑循环治疗脑血栓的临床效果。方法 :对 46例脑血栓形成患者应用当归注射液进行治疗 ,对比分析其治疗前后血浆前列环素 (PGI2 )、血栓烷A2 (TXA2 )及自由基水平。结果 :脑血栓形成患者TXA2 、丙二醛 (MDA)明显升高 ,超氧化物岐化酶 (SOD)明显降低。当归注射液治疗后上述改变明显减轻或恢复至正常组水平。结论 :当归注射液能有效调节花生四烯酸代谢产物和氧自由基水平 ,对治疗脑血栓效果明显。 相似文献
99.
Characterization of an IgA receptor from group B streptococci: specificity for serum IgA 总被引:8,自引:0,他引:8
Gunnar Lindahl Bo kerstrm Jean-Pierre Vaerman Lars Stenberg 《European journal of immunology》1990,20(10):2241-2247
Some strains of group B streptococci express a cell surface protein which binds IgA. This report describes some properties of such an IgA receptor and compares it with a previously described IgA receptor from group A streptococci. The group B receptor was released in an almost pure form from bacteria incubated at elevated pH, and could be isolated by IgA-Sepharose affinity chromatography. The sequence of the N-terminal 19 amino acid residues was unique. The receptor preferentially binds IgA of human origin, as shown in immunoblotting experiments with purified IgA from nine different species. The affinity constant of the purified receptor for serum IgA was determined to be 3.5 x 10(8) M-1, but for secretory IgA it was too low to allow determination. This result indicates that secretory component and/or J chain interferes with the binding of IgA to this type of bacterial receptor, which may be one of the physiological functions of these polypeptides. A reduction in affinity was also observed for another complexed form of IgA, alpha 1-microglobulin-IgA. The group B receptor is antigenically unrelated to the IgA receptor from group A streptococci (protein Arp), but competitive inhibition experiments indicate that they bind to the same region in IgA. The implications of these findings, and the biological role of bacterial IgA receptors, are discussed. 相似文献
100.
Objective To study on adsorption effect of cadusafos and atropine sulfate by hemoperfusion.Method Hemoperfusions were performed for sheep blood samples with cadusafos and atropineby through imitated extracorporeal closed circulating perfusion apparatus.Residual cadusafos was determined by gas chromatography and residual atropine was determined by high performance liquid chromatography.Result Dose of adsorption agent was 0.5,1.0 and 1.5 g,respectively.Two hours after hemoperfusion with membrane coated activated charcoal,clearance rate of cadusafos in 3 groups all exceeded 90%.and clearance rate of atropine sulfate was 61.9%,84.9%,88.9%,respectively.One and a half hours after hemoperfusion with HA230 absorption resin,clearance rate of eadusafos in 3 groups all exceeded 90%,and clearance rate of atropine sulfate was 88.0%,97.2%,98.4%,respectively.Three hours after hemoperfusion with membrane coated activated charcoal,The concentration ratio of cadusafos and atropine sulfate in blood promoted to 10.1 times,and the ratio was 6.7 times after hemoperfusion with HA230 absorption resin.Conclusion It suggested that cadusafos were mostly removed from blood after 1.5~2.0hours hemoperfusion with membrane activated charcoal or HA230 absorption resin.The concentration ratio of cadusafos and atropine sulfate in blood will increased after hemoperfusion. 相似文献