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71.
随着临床试验数量的增加,系统评价越来越多地被用于分析总结跨学科的科研结果。Meta分析作为一种综合证据的常用方法,能提供总结大量证据的简捷途径,但meta分析不可能适合全部多相性的临床研究,为此,就要用一种定性的方法替代它。总体印象法(Global Impression Method,GIM)作为系统评价中综合多相性临床随机对照试验(Randomized Controlled Trial,RCT)结果的常用方法,作者对其研究现状进行了总结。结果提示,使用总体印象法和最佳证据合成简化版判定森林图的结果与Meta分析的结果存在中等以上程度的内在及交互一致,因此,研究者可用GIM总结RCT结果。经过正常程序以后,在决定证据的精确强度时,个别研究的质量也被考虑,因此,GIM值得在针灸研究中应用。  相似文献   
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BACKGROUND: The ability of abciximab to prevent fibrinogen binding to activated platelets indicates it may also promote dissolution of platelet-rich thrombi. The present study examined the capacity of abciximab to reverse platelet aggregation in vitro. METHODS AND RESULTS: Experiments were performed on blood from healthy non-medicated donors. Platelet aggregate formation and disaggregation were monitored turbidimetrically. Platelet-bound fibrinogen was measured by flow cytometry. For disaggregation studies, platelets were first stimulated with either ADP or the 11-mer thrombin receptor activating peptide (TRAP), then varying amounts of abciximab were added at periodic intervals after agonist addition. Platelet disaggregation was detected by comparing the extent of light transmittance at 4 min after addition of either abciximab or saline to PRP. ATP release was simultaneously monitored by chemi-luminescence. When added 1 min after low concentrations of ADP, abciximab rapidly (< 1 min) dispersed platelet aggregates in a dose-dependent manner, with complete disaggregation observed with 6.25 microg/mL of the beta3 antagonist. In contrast, equivalent concentrations of abciximab did not induce appreciable disaggregation to platelets stimulated with TRAP (10 microM). Platelet counts of samples that had undergone complete disaggregation, as assessed by aggregometry, were equivalent to baseline, indicating dispersal of aggregates to single cells. Concentrations of abciximab that produced complete disaggregation induced partial displacement of platelet-bound fibrinogen (52 +/- 8% inhibition of fibrinogen binding at 12.5 microg/ml abciximab). The disaggregation effectiveness of abciximab decreased as the time between ADP and subsequent abciximab addition widened, and as the amount of both dense granule release and agonist stimulation increased. However, pre-treatment of platelets with acetylsalicylic acid (ASA) did not potentiate platelet disaggregation induced by abciximab. CONCLUSIONS: These data indicate that abciximab facilitates the dispersal of newly formed platelet aggregates in vitro, by partially displacing fibrinogen from activated GPIIb/IIIa receptors. In vivo, abciximab may destabilize coronary thrombi by preventing aggregate formation and dispersing mural thrombi.  相似文献   
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Juvenile acanthosis nigricans and insulin resistance   总被引:1,自引:0,他引:1  
Acanthosis nigricans in obese adolescents is frequently associated with hyperinsulinemia and insulin resistance. We report three cases of this condition. In the early stage the skin lesions appeared to be erythematous and pruritic, mimicking an inflammatory dermatitis. Dietary control and oral metformin hydrochloride markedly improved the lesions. Topical calcipotriol may also help to control the skin condition.  相似文献   
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OBJECTIVE: To assess the clinical value of low maternal serum unconjugated estriol (E3) level for diagnosing Smith-Lemli-Opitz syndrome and other fetal clinical conditions in pregnant members of a large health maintenance organization. METHODS: We studied serum unconjugated E3 levels in 120,071 gravidas having California Expanded Alpha-Fetoprotein prenatal screening at 15-20 weeks' gestation during a 5-year period. RESULTS: Of the 120,071 women, 323 (0.27%) had low unconjugated E3 levels (less than or equal to 0.2 ng/mL, or 0.15 multiples of the median). Excluding women who were screened too early or who had indeterminate screening results, 103 (0.08%) women with unexplained low unconjugated E3 level remained; of these 103 women, 33 had negative screening results and 68 had positive screening results, and two were tested too late for interpretation. Intrauterine fetal death occurred in 39 (57%) of the 68 women with low unconjugated E3 and positive screening results and occurred in two (6%) of the 33 women with low unconjugated E3 levels and negative screening results, a significant difference (P <.001). Two cases of Smith-Lemli-Opitz syndrome were identified and the patients did not survive the neonatal period; one was a therapeutic abortion for severe oligohydramnios, and the other died at age 48 hours. Low unconjugated E3 level also predicted presence of steroid sulfatase deficiency, a much more common X-linked skin disorder characterized by ichthyosis. CONCLUSION: Low maternal serum unconjugated E3 diagnosed more cases of steroid sulfatase deficiency and undetected intrauterine fetal death than Smith-Lemli-Opitz syndrome (1:60,000 prevalence), although the clinical importance of having this information prenatally is uncertain.  相似文献   
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Quality of Life Research - To examine the relationship of family functioning on health-related quality of life (HRQoL) among methadone maintenance patients using the Bayesian approach. A...  相似文献   
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Follicular lymphomas (FLs) are a heterogeneous group of tumors, but prognostic factors are evaluated insufficiently in this common hematologic neoplasm. While bcl-6 and CD10 are expressed characteristically in FLs, their significance for biologic behavior of FL has not been studied previously. Samples from 73 patients with FL and clinical follow-up from 7 to 231 months were evaluated by immunohistochemical analysis. Patients with high levels of bcl-6 expression had favorable overall survival (OS) (P = .003), disease-specific survival (DSS) (P = .033), and time to treatment failure (P = .003) compared with patients with low levels of bcl-6 expression. Multivariate analysis showed that the results for OS, DSS, and time to treatment failure were independent of the international prognostic index. Patients with CD10+ FLs also had longer OS (P = .001), DSS (P = .007), and time to treatment failure (P = .004), and grade 1 FL was associated with better OS (P = .01) and a statistical trend for longer DSS (P = .05) and time to treatment failure (P = .05), but these results were not independent of bcl-6 expression or the international prognostic index in multivariate analysis.  相似文献   
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