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We report on the clinical and pathologic findings in a girl with isochromosome 18q (46, XX,i(18q)) who had combined manifestations of monosomy 18p and trisomy 18q. Major congenital anomalies included premaxillary agenesis, alobar holoprosenphaly, double Outlet right ventricle, DiGeorge anomaly and streak ovaries. The clinical spectrum in i(18q) is very broad. © 1993 Wiley-Liss, Inc.  相似文献   
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Decreased human semen quality and organochlorine compounds in blood   总被引:7,自引:0,他引:7  
BACKGROUND: Various studies have been performed in which potential effects of xenoestrogens on fertility or sperm parameters were investigated by comparing groups of subjects exposed to different levels of these chemicals. METHODS: In our study we used an alternative approach, as we selected one group of men with very poor semen quality and another group with normal semen quality and determined the blood organochlorine contents in order to determine whether a difference in these levels could be established. Organochlorine compounds, including polychlorinated biphenyls (PCB) and PCB metabolites, were detected using gas chromatography. The concentrations were compared between both groups, and related to semen parameters. RESULTS: A comparison of both groups did not reveal significant differences in organochlorine levels. Linear relationships were found when PCB and metabolite concentrations were related to the age of the volunteers. Focusing on the subgroup of men with normal semen quality showed that sperm count and sperm progressive motility were inversely related to the concentrations of PCB metabolites within this group. CONCLUSIONS: The finding of a significantly decreased sperm count in relation to an elevated PCB metabolite level within the subgroup of men with normal semen quality is important. This is the first time that a correlation between exposure to environmental pollutants with endocrine-disrupting capacity and human sperm quality has been observed.  相似文献   
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BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy.  相似文献   
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BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease.  相似文献   
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We compared the long-term immunologic and virologic efficacy of the dual- and triple-nucleoside therapy for HIV infection. This was a retrospective analysis of 2 randomized clinical trials in antiretroviral-naive patients. In the dual-nucleoside group, 15 started with didanosine (ddI) monotherapy and then added stavudine (d4T) after 24 weeks, 63 started with various doses of d4T and ddI, and 53 started with zidovudine (ZDV) and lamivudine (3TC). In the triple-nucleoside group, 53 started with ZDV, 3TC, and ddI. After 48 weeks, patients who were not failing were randomized to immediate (before treatment failure) versus delayed (at the time of virologic failure) switching from ddI and d4T to ZDV and 3TC or vice versa and from ZDV, 3TC, and ddI to d4T, 3TC, and abacavir (ABC). Failure was defined as a plasma HIV-1 RNA level>or=1 log10 above nadir or >or=10,000 copies/mL when nadir was <500 copies/mL. Patients failing therapy before week 48 received the new treatment as in the immediate switching group. Hydroxyurea was added to the last treatment regimen if patients failed after week 96. CD4 count and plasma HIV-1 RNA level (branched DNA assay with a cutoff point of 50 copies/mL) at week 144 were analyzed by intention to treat. Compared with the dual-nucleoside group, the triple-nucleoside group had a higher proportion of patients with <50 copies/mL at 144 weeks (60% vs. 18%; P<0.001), higher median CD4 count (388 cells/microL vs. 346 cells/microL; P=0.018), and longer duration of response, defined as the time from onset of viral suppression (<500 copies/mL) to the time of treatment failure (the first of 2 consecutive HIV-1 RNA measurements >500 copies/mL never followed by 2 consecutive visits showing suppressible viremia to <500 copies/mL) or discontinuation from the study (144 weeks vs. 104 weeks; P=0.002). Multivariate regression analyses showed that significant predictors for treatment success, defined as a plasma viral load <50 copies/mL at week 144, were asymptomatic clinical status at enrollment, a baseline plasma viral load 相似文献   
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A total of 72 HIV-1 infected Thai patients treated with didanosine (ddI) or stavudine (d4T) plus ddI at the time of interim analysis were analyzed. Sixty patients (83%) carried subtype E documented by HIV-1 V3 serotyping. HIV-1 RNA levels were measured using three commercial viral load assays. At baseline (n = 57), Quantiplex 2.0 and NucliSens 2.0 showed mean log10 HIV-1 RNA of 0.7 log10 or 5 fold lower than Amplicor 1.5 (mean 4.29 versus 5.0 log10, respectively, p < 0.001). At week 20 of treatment (n = 29), HIV-1 RNA levels were detected in 55.2%, 31%, and 33.5% of subjects tested by Amplicor 1.5, Quantiplex 2.0, and NucliSens 2.0, respectively. In conclusion: plasma HIV-1 RNA analyses showed comparable values with Quantiplex 2.0 and NucliSens 2.0 assays. In contrast, Amplicor 1.5 resulted in approximately 5 folds higher HIV-1 RNA levels and a 25% higher rate of detection of plasma HIV-1 RNA as compared to the other two assays. As the current goal of therapy is to suppress plasma viral load below the detection limit of the assays, the significant differences between the assays may influence antiretroviral efficacy evaluation and management.  相似文献   
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