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81.
William F Astle Vivian E Hill Anna L Ells Nguyen Thi Thanh Chi Elaine Martinovic 《Journal of AAPOS》2003,7(5):339-344
BACKGROUND: Congenital absence of the inferior rectus muscle is a rare cause of apparent inferior rectus palsy especially in the absence of associated cranial facial anomalies. METHODS: We report three cases of isolated congenital absence of the inferior rectus muscle and its successful surgical management. RESULTS: Failure of the normal embryologic development of the mesodermal complex around the eye can lead to agenesis of the extraocular muscles. In apparent palsies of the inferior rectus muscle and no definite cause, a high index of suspicion and orbital imaging can confirm the diagnosis of congenitally absent inferior rectus preoperatively. Surgical correction may involve inferior transposition of the horizontal rectus muscles. CONCLUSIONS: Although rare, congenital absence of the inferior rectus muscle is a possible cause of apparent inferior rectus muscle palsy particularly in the absence of another identifiable cause. Strabismus surgery in conjunction with intramuscular botulinum toxin injection can offer significant improvement in function and cosmesis of these patients. 相似文献
82.
我国食管癌发病危险因素的Meta分析 总被引:2,自引:0,他引:2
目的:评价我国食管癌发病的危险因素。方法:通过Meta分析对国内13篇公开发表的有关食管癌发病危险因素的病例-对照研究进行定量综合分析,共对12个因素进行评价,计算每个因素的综合OR值.结果:共有9个因素有显意义,分别为:吸烟(ORs=1.69)、饮酒(ORs=1.81)、酸菜(0Rs=2.22)、烫食(ORs=2.41)、家族史(ORs=4.00)、精神因素(ORs=3.06)、干硬食物(ORs=2.07)、吃饭快(ORs=1.82)、水果(ORs=0.39).结论:吸烟、饮酒、酸菜、烫食、家族史、精神因素、干硬食物及吃饭快为食管癌发病的危险因素,水果为保护因素,而蔬菜、饮茶以及肉类对食管癌发病的作用尚不能确定。 相似文献
83.
Childhood kidney tumors seldom metastasize into the cranial cavity unless it is a special histological variant. We report a 4-year-old boy with multiple intracranial metastases in the left parietotemporal and right cerebellar area from primary clear cell sarcoma of the kidney without evidence of bony metastases. Metastatic tumor revealed nests of uniformly polygonal cells with clear cytoplasm demarcated by delicate fibrovascular arcades. Tumor cells were positive for vimentin and negative for cytokeratin, S-100 protein, desmin, and myoglobin. Cellular proliferation rate measured by PCNA, and Ki-67 was not significantly different between primary tumor mass and metastatic brain lesion. Expression of p53 oncoprotein was not evident in both lesions. These findings suggested that the relapse and metastasis of clear cell sarcoma of the kidney was probably due to regrowth of micro-metastases which were present at an early stage of disease. 相似文献
84.
羊膜建库及其临床应用研究 总被引:3,自引:0,他引:3
目的 :制备与保存羊膜 (Amnioticmembrane,AM ) ,为临床移植治疗眼表泪液 (Ocularsur face&Teardisease ,OSTD)提供新鲜羊膜 (Freshamnioticmembrane ,FSAM )、冻干羊膜 (Frozenam nioticmembrane ,FZAM )并观察其眼表重建的特点与临床疗效。方法 :采用目前国际公认的羊膜制备与保存方法 ,制备FSAM、FZAM并进行保存研究 ,经组织染色和电子显微镜检查 ,观察保存羊膜的形态及其活性 ;并将FSAM、FZAM应用于 12例OSTD患者 ,行患眼FSAM或FZAM移植术。通过术后印迹细胞学追踪观察移植后AM上皮细胞存活与移行、替代时间 ,评估AM移植重建眼表的临床疗效。结果 :FSAM、FZAM在光镜和电镜下均与正常球结膜组织结构相近 ,主要结构为胶原纤维和网状纤维。 12例OSTD患者行羊膜移植术 (Amnioticmembranetransplantation ,AMT)后均未见明显急性排斥反应 ,术后 1~ 2周可见少量新生血管长入植片 ,AMT后印迹细胞学追踪检查 ,术后 3个月为阴性 ,4个月出现阳性反应。所有患者术后随访 5~ 18个月 ,平均 11个月 ,AM在术后 4~ 9个月逐渐溶解、消失 ,移植区眼表的色泽与结构基本恢复正常。结论 :FSAM、FZAM是目前理想的结膜替代材料并可有效地用于重建角、结膜表面 ,减轻炎症反应 ,减少新生血管的生成 ,抑制纤维组织增生 ,防止 相似文献
85.
86.
目的 探索如何抑制嗜酸细胞的趋化作用,选择β-趋化因子巨噬细胞炎性蛋白4(MIP4)的突变性(Met-MIP4)作为趋化因子受体3的拮抗剂,将Met-MIP4基因在原核细胞中进行表达。方法 设计MIP4基因的PCR引物并进行氨基酸突变,将MIP4N末端的丙氨酸突变为蛋氨酸,以正常人肺酸突变,将MIP4N末端的丙氨酸突变为蛋氨酸。以正常人肺cDNA文库为模板,PCR方法获取Met-MIP4基因,克隆入载体pUC19,测序验证序列已得到突变,将正确的基因插入到GST融合表达载体pGEX-4T中,以IPTG诱导表达。结果 PCR产物为220bp左右的片段,连接入pUC19质粒后测序验证获得正确突变,构建的pGEX-4T融合表达载体在大肠杆菌中表达,经SDS-PAGE凝胶电泳显示有大小约34kU的新生融合蛋白表达。结论 成功突变并克隆了β-趋化因子MIP4基因,SDS-PAGE表明,与GST融合的Met-MIP4突变体已得到表达,为进一步研究其生物学活性奠定了基础。 相似文献
87.
高脂血症患者C—反应蛋白含量的变化及氟伐他汀对它的影响 总被引:4,自引:1,他引:3
Dong-Sheng Chi Feng-Xia Jin Shu-Guang Yang Yu-Wen Su Bin Ge Jie Zhang Yan Zhang Yi-Li Liu 《第一军医大学学报》2002,22(12):1109-1111
OBJECTIVE: To observe the changes of C-reactive protein (CRP) level and its relationship with blood lipids, and the effects of fluvastatin on CRP and the lipids in patients with hyperlipidemia. METHODS: Serum levels of cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), very-low-density lipoprotein cholesterol (VLDL-C) and lipoprotein(a)[Lp(a)] were measured by enzyme assay, and plasma CRP level by immunonephelometry before and after fluvastatin treatment (20 mg/d for 4 weeks) in patients with hyperlipidemia. RESULTS: CRP levels were above normal in 90.3% hyperlipidemia cases in spite of the various accompanying diseases. Fluvastatin treatment significantly reduced TC (-7.49%), TG (-14.32%), LDL (-13.88%), VLDL (-18.48%) and TC/HDL(-13.50%) levels (P<0.01), and also brought down Lp(a) concentration (-13.81%). CRP levels was very effectively reduced after the treatment (-15.92%, P<0.001). No association between basal CRP levels and basal lipids and Lp(a) concentrations was observed. Positive correlation of CRP, however, was observed after fluvastatin treatment with TC/HDL (r=0.62, P=0.041) and Lp(a) (r=0.320, P=0.011), while inverse relations were noted between CRP and HDL (r=-0.288, P=0.023). CONCLUSION: CRP levels increases markedly in patients with hyperlipidemia, a fact that is independent of the accompanying diseases. In addition to modulating blood lipid levels, fluvastatin also reduces CRP level, the latter possibly serving as an independent predictive factor for atherosclerotic cardiovascular diseases and also as an indicator for estimating the effectiveness of the treatment. 相似文献
88.
目的:观察不同催眠感受性个体在清醒休息状态和催眠状态下的脑电图半球优势的差异。方法:2003-06/2004-01对成都市6所高校169名正常汉族大学生(四川大学、成都中医药大学、四川师范学院、四川教育学院、成都体育学院、西南民族学院)用斯坦福团体催眠感受性量表C式进行施测,其中总分0~3分为低催眠感受性组,总分4~6分为中催眠感受性组,总分7~11分为高催眠感受性组。进行脑电图测试时,判断受试者是否进入催眠状态标准为:①进入催眠状态:受试者在催眠诱导后的语言抑制、眼皮僵直、催眠后遗忘、左手上浮4个项目的总分为1~4分。②未进入催眠状态:受试者得分为0分。比较进入催眠状态高催眠感受性组和低催眠感受性组在清醒、催眠状态下左、右半球脑电节律的频率指数和振幅差异。结果:参加实验169名学生,斯坦福团体催眠感受性量表C式有高、低催眠感受性的学生56名参加脑电图测试,最后进入催眠状态的50名学生进入结果分析。高催眠感受性29名,低催眠感受性21名。高感受性个体在清醒状态下慢波活动和α-2活动呈现更明显的左侧优势,θ,α,β的振幅呈现更明显的右侧优势,而低感受性个体的慢波活动及振幅没有半球优势;催眠状态下高感受性个体的慢波活动的左侧优势仍更为明显,α波和β波振幅的右侧优势仍更加突出。结论:在清醒状态和催眠状态下,高感受性个体显示出更明显的半球特征性。 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.
进一步研究了抗三尖杉酯碱的HL-60细胞(HR20)抗细胞凋亡的机制及该抗性和抗药性的关系。结果表明,环孢菌素A(CsA)20,10μg·ml ̄(-1)诱导HL-60细胞发生凋亡,而阻断HR20细胞于G_1期,就不能诱导细胞发生凋亡。低浓度的CsA明显增加柔红霉素在HR20细胞内的积聚,其逆转抗药性作用与阻断细胞周期运行无关。CsA10μg·ml ̄(-1)处理HR20细胞,可引起50kDa的蛋白质高度磷酸化。结果提示:环孢菌素A阻断抗三尖杉酯碱的HL-60细胞于G_1期,而诱导敏感的HL-60细胞发生凋亡,其阻断作用与抗药性无关 相似文献