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41.
Polymorphism p53 codon-72 and invasive cervical cancer: a meta-analysis.   总被引:4,自引:0,他引:4  
OBJECTIVES: Although some studies have reported that the arginine isoform on codon 72 of p53 increases the susceptibility to invasive cervical cancer, such data remain controversial. The objective of this study was to quantitatively summarize the evidence for such a relationship. METHODS: Our data sources consisted of a MEDLINE search of the literature published before December 2002, bibliography review, and expert consultation. Thirty-seven studies met the inclusion criteria. Information on sample size, study design, Hardy-Weinberg equilibrium, and method of genotype determination was abstracted by two reviewers using a standardized protocol. The overall odds ratio (OR) of the p53 gene on invasive cervical cancer was estimated using the Mantel-Haenzel method. RESULTS: The overall OR (95% confidence interval) for cervical cancer among those with the homozygous mutant (Arg/Arg) was 1.2 (1.1-1.3, P=0.001) compared with those with the heterozygous mutant (Arg/Pro). By a cellular type of cervical cancer, the overall OR among those with Arg/Arg was statistically significant in adenocarcinomas (1.7, 1.1-2.6, P=0.024), but not in squamous cell carcinomas (1.1, 0.9-1.2, P=0.960), compared with Pro/Pro. Compared with Arg/Pro, the OR among those with Arg/Arg was statistically significant in HPV types 16 (1,5, 1.2-2.0, P=0.002). CONCLUSIONS: Overall, the p53 gene was associated with increased risk for invasive cervical cancer. However, the risk varied by country, cellular, and HPV type.  相似文献   
42.
Background: Cicatricial deformation in child burn of hand often leads to severe squaelae. According to different causes of disease , different plastic surgery were adopted .The key of operation lies in skin repairing , articulation dealing, and thumb correcting, which aim is to resume normal longitudinal and transverse arcs ,holding and clenching ability.  相似文献   
43.
寒冷干燥地区平时火器伤的早期处理   总被引:3,自引:3,他引:0  
目的 探讨寒冷干燥地区平时火器伤伤情特点与早期救治方法。方法 对 1991年 1月— 2 0 0 2年 12月间 40例火器伤病人的临床救治进行回顾分析。结果  2 4例枪伤中 ,2 0例一期缝合伤口 ,均一期愈合 ,另外 4例只清创未一期缝合的伤口 ,3例愈合 ,1例感染 ;4例骨折内固定均愈合良好 ,无骨髓炎发生。 16例炸伤病人局部软组织损伤及污染比枪弹伤重 ,14例一期缝合伤口中 ,10例一期愈合 ,4例感染 ,骨折内固定 2例 ,均愈合良好 ,无骨髓炎发生。结论 寒冷干燥地区火器伤早期伤道清创时限可适当延长 ,在平时火器伤的救治中 ,对软组织条件较好的创面 ,早期清创后可一期闭合伤口和骨折内固定 ,这样可减少感染和伤残 ,促进康复  相似文献   
44.
目的 探讨老年腰椎间盘突出症的特点与手术治疗效果.方法 对62例老人腰椎间盘突出症患者的临床与病理特点进行分析.均行腰椎后路椎板减压髓核摘除术,其中小切口开窗35例,半椎板切除20例,全椎板切除7例,根据手术前后JOA评分评价手术疗效.结果 老年腰椎间盘突出症病理以髓核组织的脱水,纤维环的破裂,小关节囊、周围韧带及软骨终板退变为主要特点.临床特点为下肢疼痛多发,腰部活动受限较多;双下肢神经系统检查肌力下降明显,生理反射改变明显.62例平均随访1.9年,JOA评分术后平均改善率为68.9%,手术前后JOA评分比较差异有显著性意义(P<0.05).结论 老年腰椎间盘突出症患者病程长,体征多,病理改变明显,行腰椎后路椎板减压髓核摘除术,手术效果满意.  相似文献   
45.
OBJECTIVE: Our purpose was to compare the relative risk of vessel injury after use of a 5 mm conical-tipped trocar, a 5 mm pyramidal-tipped trocar, and a 10 mm pyramidal-tipped trocar in a rabbit vessel model.STUDY DESIGN: Plastic templates were placed in front of and behind 108 mesenteric vessels in 11 anesthetized New Zealand White rabbits. Laparoscopic trocars were inserted through the templates and mesentery. The incidence of vessel injury was determined at distances from the vessels ranging from 0 to 5 mm.RESULTS: The 5 mm conical trocar resulted in a vessel injury rate of 88% at 0 mm from the vessel but 0% at 1 or 2 mm. The 5 mm pyramidal trocar resulted in 100%, 88%, and 62% injury rates of 0, 1, and 2 mm from the vessels, respectively. The 10 mm pyramidal trocar resulted in a 100% injury rate at 0, 1, 2, or 3 mm from the vessels and 80% and 40% at 4 mm and 5mm, respectively.CONCLUSION: The relative risk of vessel injury is significantly increased by the use of pyramidal-tipped trocars when compared with conical-tipped trocars, especially if larger diameter trocars are used.  相似文献   
46.
Obstructive sleep apnea has traditionally been viewed as a structural disease. A multitude of systemic endocrine and cardiovascular abnormalities have been previously attributed to the prevalence of obesity in these patients. A growing body of clinical evidence, however, points to a relationship between sleep apnea and its systemic abnormalities independent of obesity. We hypothesize that this association is based on a maladaptive autonomic response of chemoreceptors, reacting to the hypoxia, hypercapnia, and acidosis of sleep apnea. The elevated sympathetic response triggers an inflammatory cascade that results in a myriad of downstream consequences including insulin resistance, hypertension, diabetes, atherosclerosis and metabolic syndrome. The sympathetic bias and endocrine disturbances may further exacerbate sleep disturbance in a potentially pernicious cycle. Our proposal may extend to any chronic respiratory or metabolic conditions that manifest hypoxia, hypercapnia, and acidosis and elicit a maladaptive autonomic and inflammatory response.  相似文献   
47.
Rapid leukocyte integrin activation by chemokines   总被引:12,自引:0,他引:12  
Summary: Chemokines control selective targeting of circulating leukocytes to the microvasculature by triggering inside-out signal transduction pathways leading to integrin-dependent adhesion. Integrin activation by chemokines is very rapid, is downmodulated within minutes and appears to involve both enhanced heterodimer lateral mobility on the plasma membrane, facilitating encounters with dispersed ligand, as well as induction of a high-affinity state. These two modalities of integrin activation by chemokines involve distinct signaling pathways in the cell, yet complement each other functionally, allowing binding of rolling cells under conditions of low as well as high ligand density. Recent data show that chemokines generate both pro- and anti-adhesive intracellular signaling events, whose equilibrium is likely to be relevant to the kinetics of adhesion and de-adhesion, and to cell movement during diapedesis and chemotaxis. Importantly, chemokines utilize different signaling mechanisms to modulate the activity of distinct integrin subtypes. These recent advances suggest that chemokines may regulate adhesive responses of immune cells based not only on patterns of chemokine receptor expression, but also on variable signaling pathways that can modulate the pro-adhesive responses of leukocytes as a function of their differentiated state, and of the local microenvironment.  相似文献   
48.
M R Fortson  J R Scott  T Yun  D Vapnek 《Virology》1979,96(1):332-334
The kanamycin resistance determinant in P1Km lies between am33 and gene 2 on the P1 genetic map. This is within the invertible region (C loop) of P1 DNA.  相似文献   
49.
本实验用 4~ 5月龄和 15~ 16月龄的 app/ ps1dtg小鼠各 5只 ,同龄野生型小鼠每个年龄组各 5只 ,用β-NADPH组织化学染色显示神经元一氧化氮合酶活性 ,刚果红组织学染色显示神经炎性斑 ,无偏性体视学计量皮质和海马神经炎斑的总体积 ,研究神经元一氧化氮合酶活性在 app/ ps1双转基因 (app/ ps1dtg) AD模型小鼠大脑皮质和海马的异常分布 ,探讨其在该模型小鼠及 AD患者脑内病理改变中的作用。结果显示 ,n NOS阳性神经元在各组小鼠皮质和海马内的分布没有区别 ,4~ 5月龄 app/ps1dtg小鼠皮质和海马可见神经炎斑 (NP)和营养不良性 NOS阳性神经突 (DTN) ;15~ 16月龄 app/ ps1dtg小鼠皮质和海马内NP的体积分别是 4~ 5月龄 app/ ps1dtg小鼠皮质 NP的 5倍 (P<0 .0 0 5 )和 8倍 (P<0 .0 0 1) ;15~ 16月龄 app/ ps1dtg小鼠皮质内 DTN的体积明显增大 (P<0 .0 1) ;且伴有 NOS阳性神经元形态的改变及海马 CA1 区 NOS阳性神经元数量的减少 (P<0 .0 5 ) ,DTN的形成与 NP呈正相关关系 (r=0 .85 ,P<0 .0 5 )。本实验结果表明 ,app/ ps1dtg小鼠能够模拟 AD患者脑内 NOS阳性神经元的病理改变 ,DTN的形成可能与 Aβ的毒性作用有关 ,DTN产生的 NO可能参与 app/ ps1dtg小鼠和 AD的神经病理过程。  相似文献   
50.
心音信号的分形研究   总被引:3,自引:0,他引:3  
本文通过引入分形概念,首次为描述心音信号的复杂程度给出了一个定量的指标——分数维数。研究结果表明:心音信号确实存在着“无标度区”,具有典型的分形特性;心音信号的分维值能显著性地区分正常心音、二尖瓣病变心音(包括二尖瓣狭窄、二尖瓣关闭不全及二尖瓣狭窄加关闭不全)和主动脉瓣病变心音(主动脉瓣狭窄、主动脉瓣关闭不全及主动脉瓣狭窄加关闭不全)。  相似文献   
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