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Thirty-three patients were treated with HexAF after previous treatment with cyclophosphamide (C), Adriamycin (A), and cisplatin (P). The patients had either progressed on CAP, had persistent disease after CAP, or recurred after a negative second look. Treatment schedule was hexamethylmelamine (Hex) 150 mg po qd days 1-14, methotrexate (A) 40 mg/m2 IV days 1 and 8, and 5-fluorouracil (F) 600 mg/m2 IV days 1 and 8. Courses were repeated every 4 weeks. Thirty-one of 33 patients were evaluable for response. Three of 31 patients had partial responses, 7 of 31 had stable disease, and 21 of 31 progressed. Median survival of the responders (n = 3) was 23 months and the nonresponders (n = 28) was 6 months (p = 0.027). Patients with less than 1 cm disease (n = 12) had a median survival of 20 months, and those with greater than 1 cm (n = 21) had a median survival of 6 months (p = 0.004). Toxicity was mild. Even with a statistically significant survival advantage for HexAF responders, we consider a response rate of less than 10% unacceptable.  相似文献   
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Our objective was to test if protease inhibitors (PIs) increase the incidence of fetal growth restriction (FGR). Human immunodeficiency (HIV)-seropositive women were studied. At birth the neonatal weight percentile was assigned by predicted growth potential (GP), accounting for race, parity, weight, height, gestational age, birthweight, and gender (Gardosi, 1992). FGR was defined as GP < 10% percentile. Maternal age, CD4 count, viral load, weight gain, prenatal care, tobacco, alcohol, substance abuse, and PI use were related to FGR using chi-square and multiple regression analysis. Ninety-three of 191 women received PI. In these, FGR occurred in 27 (29%) compared with 15 (15.3%) in the non-PI group ( P = 0.02). Maternal CD4 count ( P < 0.0001) was the primary determinant, and smoking ( P = 0.037) was an independent cofactor for FGR (Nagelkerke r2 = 0.24). Twenty-six of 82 (31.7%) smokers had FGR, versus 16 of 109 (14.7%) of nonsmokers (odds ratio, 2.69; 95% confidence interval, 1.33 to 5.46; P = 0.005). After exclusion of the CD4 count, PI became a cofactor for FGR ( P = 0.021 and Nagelkerke r2 = 0.104). We concluded that maternal HIV status and smoking determine the risk for FGR. Although PIs increase the risk for FGR, this effect appears to depend on maternal disease severity.  相似文献   
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Poliomyelitis virus was propagated in vitro successfully in extraneural tissues. Suspended tissue fragment cultures and combined plasma clot-suspended tissue fragment cultures of monkey or human testicular tissues were employed. Five strains representative of poliomyelitis virus were maintained for from 36 to 263 days in the suspended tissue fragment type of culture. The dilution factors calculated by tissue replacements for the eight serial passages ranged from 107.8 to 1044.5 and when assessed by fluid replacements, from 1015 to 1095.3. The LD50 for each strain of Type 2 virus was determined for selected transfers. The identify of each strain of virus was established by neutralization tests and histopathological findings in monkeys dead from the injection of tissue culture virus. Control experiments and other tests made known that propagation of poliomyelitis virus did not occur in the absence of viable testicular cells and that an extraneous virus was not inadvertently acquired during the course of these studies.  相似文献   
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In causal studies without random assignment of treatment, causal effects can be estimated using matched treated and control samples, where matches are obtained using estimated propensity scores. Propensity score matching can reduce bias in treatment effect estimators in cases where the matched samples have overlapping covariate distributions. Despite its application in many applied problems, there is no universally employed approach to interval estimation when using propensity score matching. In this article, we present and evaluate approaches to interval estimation when using propensity score matching.  相似文献   
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Introduction:HIV confers increased risk of myocardial infarction (MI), but there has been little study of ischemic electrocardiogram (ECG) findings among people with HIV in sub-Saharan Africa.Objectives:To compare the prevalence of ischemic ECG findings among Tanzanians with and without HIV and to identify correlates of ischemic ECG changes among Tanzanians with HIV.Methods:Consecutive adults presenting for routine HIV care at a Tanzanian clinic were enrolled. Age- and sex-matched HIV-uninfected controls were enrolled from a nearby general clinic. All participants completed a standardized health questionnaire and underwent 12-lead resting ECG testing, which was adjudicated by independent physicians. Prior MI was defined as pathologic Q-waves in contiguous leads, and myocardial ischemia was defined as ST-segment depression or T-wave inversion in contiguous leads. Pearson’s chi-squared test was used to compare the prevalence of ECG findings among those with and without HIV and multivariate logistic regression was performed to identify correlates of prior MI among all participants.Results:Of 497 participants with HIV and 497 without HIV, 272 (27.8%) were males and mean (sd) age was 45.2(12.0) years. ECG findings suggestive of prior MI (11.1% vs 2.4%, OR 4.97, 95% CI: 2.71–9.89, p < 0.001), and myocardial ischemia (18.7% vs 12.1% OR 1.67, 95% CI: 1.18–2.39, p = 0.004) were significantly more common among participants with HIV. On multivariate analysis, ECG findings suggestive of prior MI among all participants were associated with HIV infection (OR 4.73, 95% CI: 2.51–9.63, p = 0.030) and self-reported family history of MI or stroke (OR 1.96, 95% CI: 1.08–3.46, p = 0.023).Conclusions:There may be a large burden of ischemic heart disease among adults with HIV in Tanzania, and ECG findings suggestive of coronary artery disease are significantly more common among Tanzanians with HIV than those without HIV.  相似文献   
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