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目的 比较文拉法辛与三环抗抑郁药治疗抑郁症临床痊愈率的差异。方法 应用循证医学的Me-ta分析,采用固定效应模型(fixed effects model,FEM)法对符合标准的16项对照研究文献进行评价。结果 文拉法辛与三环抗抑郁药治疗抑郁症的临床痊愈率不同,差异有显著性(χ2=4.773,df=1,P<0.05);综合的ORs=1.36,95%CI为1.04~1.78。提示文拉法辛治疗抑郁症的临床痊愈率是三环抗抑郁药的 1.36倍。结论 治疗抑郁症,文拉法辛比三环抗抑郁药有更可靠的临床痊愈率。 相似文献
23.
磁共振扩散加权成像对超急性期、急性期脑缺血的应用价值 总被引:3,自引:0,他引:3
磁共振扩散加权成像(DWI)可以快速、无创地反映脑缺血区分子水平发生的微观变化,为临床提供信息,本文对其在超急性期、急性期脑缺血的应用价值和限度进行综述。 相似文献
24.
S J Dwyer B K Stewart J W Sayre D R Aberle M I Boechat J C Honeyman J M Boehme H Roehrig T L Ji G J Blaine 《Radiographics》1992,12(4):765-772
Gray-scale monitors are an essential element of electronic radiology, and their ability to provide images that are perceived to be identical to those available on conventional or laser-printed film is crucial to success of electronic radiology. Image fidelity is measured in physical characteristics (luminance, dynamic range, distortion, resolution, and noise) and with psychophysical techniques, including receiver operator characteristics analysis with clinical images and testing with contrast-detail patterns to determine threshold contrast. Currently, laser-printed images facilitate greater information transfer than does a gray-scale monitor because of their higher absolute luminance (500 ft-L vs 60 ft-L), greater perceived dynamic range, and better spatial resolution. In the near future, the developments of gray-scale monitors with 150-200 ft-L luminance, a display standard based on just noticeable differences, and algorithms to improve similarities between gray-scale display images and laser-printed images will help increase the acceptability of monitors as a means to make primary diagnoses. 相似文献
25.
在现代化医院面临国内国际竞争时,医院双语服务摆到了医院管理者的议事日程上来。医院双语服务,特别是医院外语(英语)标识应采用国际化、标准化外语(英语)。医院使用双语标识时应注意几个问题: 相似文献
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S H Jee S Y Won J E Yun J E Lee J S Park S S Ji 《International journal of gynaecology and obstetrics》2004,85(3):301-308
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
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Natural killer/T-cell lymphoma (NKTL) and peripheral T-cell lymphomas (PTCL) are prevalent in the Asian population and exhibit a high association with the Epstein-Barr virus (EBV). Moreover, differentiation of these two groups is often difficult and problematic. We investigated 35 cases of NKTL (22 nasal cases and 13 extranasal cases) and 30 cases of PTCL in terms of their clinical features, immunohistology, EBV positivity, EBV strain-type polymorphism and latent membrane protein 1 (LMP1) deletion variant distribution. Eighteen cases (82%) of nasal NKTL and seven (54%) of extranasal NKTL showed EBV positivity by EBV in situ hybridization. Fifteen cases (50%) of PTCL revealed EBV positivity. EBV strain type A was predominant in NKTL (18:5), and EBV strain types A and B were distributed evenly in PTCL (6:6). EBV-positive patients had significantly shorter survival than EBV-negative patients (P < 0.05), and EBV positivity correlated with advanced clinical stage (P < 0.05). Patients harboring type A EBV showed slightly poorer prognoses than those having type B, though it was not obviously statistically different (P = 0.07). The LMP1 deletion variant was prevalent in both NKTL (three wild-type LMP1, 15 deletion variants) and PTCL (three wild-type LMP1, eight deletion variants, two coexistent forms) patients, but did not have prognostic impact. Our results indicate that EBV acts as a negative prognostic factor in NKTL and PTCL, and that the intrinsic properties of a specific viral strain might influence the clinical behavior of these diseases. 相似文献
30.
Rapid leukocyte integrin activation by chemokines 总被引:12,自引:0,他引:12
Carlo Laudanna Ji Yun Kim Gabriela Constantin Eugene C. Butcher 《Immunological reviews》2002,186(1):37-46
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