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71.
Population-based estimates of human immunodeficiency virus (HIV) prevalence and risk behaviors among men who have sex with men (MSM) are valuable for HIV prevention planning but not widely available, especially at the local level. We combined two population-based data sources to estimate prevalence of diagnosed HIV infection, HIV-associated risk-behaviors, and HIV testing patterns among sexually active MSM in New York City (NYC). HIV/AIDS surveillance data were used to determine the number of living males reporting a history of sex with men who had been diagnosed in NYC with HIV infection through 2002 (23% of HIV-infected males did not have HIV transmission risk information available). Sexual behavior data from a cross-sectional telephone survey were used to estimate the number of sexually active MSM in NYC in 2002. Prevalence of diagnosed HIV infection was estimated using the ratio of HIV-infected MSM to sexually active MSM. The estimated base prevalence of diagnosed HIV infection was 8.4% overall (95% confidence interval [CI] = 7.5–9.6). Diagnosed HIV prevalence was highest among MSM who were non-Hispanic black (12.6%, 95% CI = 9.8–17.6), aged 35–44 (12.6%, 95% CI = 10.4–15.9), or 45–54 years (13.1%, 95% CI = 10.2–18.3), and residents of Manhattan (17.7%, 95% CI = 14.5–22.8). Overall, 37% (95% CI = 32–43%) of MSM reported using a condom at last sex, and 34% (95% CI = 28–39%) reported being tested for HIV in the past year. Estimates derived through sensitivity analyses (assigning a range of HIV-infected males with no reported risk information as MSM) yielded higher diagnosed HIV prevalence estimates (11.0–13.2%). Accounting for additional undiagnosed HIV-infected MSM yielded even higher prevalence estimates. The high prevalence of diagnosed HIV among sexually active MSM in NYC is likely due to a combination of high incidence over the course of the epidemic and prolonged survival in the era of highly active antiretroviral therapy. Despite high HIV prevalence in this population, condom use and HIV testing are low. Combining complementary population-based data sources can provide critical HIV-related information to guide prevention efforts. Individual counseling and education interventions should focus on increasing condom use and encouraging safer sex practices among all sexually active MSM, particularly those groups with low levels of condom use and multiple sex partners At the time this work was conducted, Manning and Marx were with the Epidemic Intelligence Service, Office of Workforce and Career Development, Centers for Disease Control and Prevention, Atlanta, GA, USA; Thorpe, Ramaswamy, Hajat, Marx, Karpati, Mostashari, and Pfeiffer are with the New York City Department of Health and Mental Hygiene, New York, NY, USA; Nash is with the Department of Epidemiology and International Center for AIDS Care and Treatment Programs, Columbia Mailman School of Public Health, New York, NY, USA; Manning is with the Massachusetts Department of Public Health, Bureau of Family and Community Health, Boston, MA, USA.  相似文献   
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Orofacial defects can be either congenital or acquired. Rehabilitation of these patients can be done using a surgical and/or a prosthetic approach. In situations where surgical reconstruction is not possible, prosthetic management becomes the only option. This clinical report describes a simple, economical, and effective technique for the prosthetic rehabilitation of a patient with oro-cutaneous fistula due to donor site dehiscence following tumor defect reconstruction.  相似文献   
74.
A case of a functioning invasive pituitary oncocytoma in a 50-year-old man is reported. The serum prolactin was increased and immunocytochemical staining was positive for prolactin. In addition to numerous mitochondria within the neoplastic cells, structurally abnormal mitochondria with crystalline inclusions were also present. Another interesting feature was the presence of about 10 to 15% of non-oncocytic cells which showed prominent RER and Golgi apparatus as found in functioning pituitary adenomas. It is likely that these secretorily active cells were responsible for the functional activity of the tumour.  相似文献   
75.
Ependymomas are CNS tumors that originate from the spinal canal and walls of the ventricular system. Considerable controversy continues to exist with regard to their prognostic factors; age and extent of resection are the only statistically significant prognostic factors yet identified. The authors report a retrospective study of a homogenous population of 119 patients harbouring ependymomas between 1991 and 2002. All clinico‐radiological and follow‐up data were analyzed and a pathologic review was performed by two pathologists. Immunohistochemical staining for MIB‐1, Topo IIα, p53 and MDM2 was performed. Histopathologic grades show relationship with MIB1 and Topo IIα labelling indices and cut‐off values of 5% can differentiate between anaplastic and lower grades. p53 and MDM2 proteins expression are not common in ependymomas; however, they are seen in higher grades only and may be involved in the tumor progression.  相似文献   
76.
Objective  Bacterial vaginosis (BV) and Trichomonas vaginalis infection (TV) have been associated with adverse birth outcomes and increased risk for HIV. We compare the performance of simple inexpensive point-of-care (POC) tests to laboratory diagnosis and syndromic management of BV and TV in poor settings.
Methods  Between November 2005 and March 2006, 898 sexually active women attending two reproductive health clinics in Mysore, India were recruited into a cohort study investigating the relationship between vaginal flora and HSV-2 infection. Participants were interviewed and screened for reproductive tract infections. Laboratory tests included serology for HSV-2; cultures for TV, Candida sp., and Neisseria gonorrhoeae ; Gram stains; and two POC tests: vaginal pH; and Whiff test.
Results  Of the 898 participants, 411 [45.7%, 95% confidence interval (95% CI): 42.4–49.0%] had any laboratory diagnosed vaginal infection. BV was detected in 165 women (19.1%, 95%CI: 16.5–21.9%) using Nugent score. TV was detected in 76 women (8.5%, 95%CI: 6.7–10.4%) using culture. Among the entire study population, POC correctly detected 82% of laboratory diagnosed BV cases, and 83% of laboratory diagnosed TV infections. Among women with complaints of vulval itching, burning, abnormal vaginal discharge, and/or sores (445/898), POC correctly detected 83% (60 of 72 cases) of laboratory diagnosed BV cases vs. 40% (29 of 72 cases) correctly managed using the syndromic approach ( P  <   0.001). Similarly, POC would have detected 82% (37 of 45 cases) of TV cases vs. 51% (23 of 45 cases) correctly managed using the syndromic approach ( P  =   0.001).
Conclusions  In the absence of laboratory diagnostics, POC is not only inexpensive and practical, but also significantly more sensitive than the syndromic management approach, resulting in less overtreatment.  相似文献   
77.
OBJECTIVE: This randomized, double-blind, parallel group multicenter study compared response rates and tolerability of zolmitriptan with sumatriptan in the acute treatment of migraine. METHODS: A sample consisting of 1445 outpatients with an established diagnosis of migraine was randomized to zolmitriptan, 2.5 mg or 5 mg, or sumatriptan, 25 mg or 50 mg. Patients took 1 tablet for moderate/severe migraine and a second identical tablet, if necessary, for recurrent headache of moderate/severe intensity 4 to 24 hours after the initial dose. Up to six attacks were treated during a 6-month period. The primary outcome measure was headache response 2 hours after the initial dose. Secondary end points included 1-hour and 4-hour headache response and pain relief over 24 hours. RESULTS: A headache response at 2 hours was noted in 67.1% of patients taking zolmitriptan, 2.5 mg, and 64.8% of those taking zolmitriptan, 5 mg, versus 59.6% of patients taking sumatriptan, 25 mg, and 63.8% of those taking sumatriptan, 50 mg. At 2 and 4 hours, the differences between zolmitriptan, 2.5 mg, and sumatriptan, 25 mg, were statistically significant (odds ratio=1.49 and 1.67, respectively; both P<.001). Statistically significant differences between zolmitriptan, 2.5 mg, and sumatriptan, 50 mg, were seen at 2 and 4 hours post dose (odds ratio=1.21 and 1.23, respectively; both P<.05). At 1 hour post dose, the headache response rate for zolmitriptan, 2. 5 mg, was numerically higher than response rates for sumatriptan, 25 mg and 50mg (odds ratio=1.16, odds ratio=1.06, though they failed to reach statistical significance; P=.061, P=.461 respectively). Differences between zolmitriptan, 5 mg, and sumatriptan, 25 mg, were statistically significant at 1, 2, and 4 hours (odds ratio=1.43, 1. 46, and 1.78, respectively; all P<.001) and at 1 and 4 hours versus sumatriptan, 50 mg (odds ratio=1.28, P=.002; odds ratio=1.29, P=.012, respectively). Although not statistically significant at 2 hours, more patients responded to zolmitriptan, 5 mg, than to sumatriptan, 50 mg (odds ratio=1.16, P=.064). Patients receiving zolmitriptan, 2. 5 mg or 5 mg, achieved more pain relief over 24 hours than patients receiving sumatriptan, 25 mg (odds ratio=1.47, and 1.54 respectively, both P<.001) or sumatriptan, 50 mg (odds ratio=1.17, P=.021; odds ratio=1.22, P=.005, respectively). All treatments were well tolerated. CONCLUSIONS: Zolmitriptan, 2.5 mg and 5 mg, was at least as effective as sumatriptan, 25 mg or 50 mg, for all parameters studied. Zolmitriptan, 2.5 mg, was significantly more effective than sumatriptan, 50 mg, in terms of headache response at 2 and 4 hours. Patients taking zolmitriptan were significantly more likely to have pain relief over 24 hours than those taking sumatriptan.  相似文献   
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Tamoxifen is primarily used in the treatment of breast cancer. It has been approved as a chemopreventive agent for individuals at high risk for this disease. Tamoxifen is metabolized to a number of different products by cytochrome P450 enzymes. The effect of tamoxifen on the enzymatic activity of bacterially expressed human cytochrome CYP2B6 in a reconstituted system has been investigated. The 7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation activity of purified CYP2B6 was inactivated by tamoxifen in a time- and concentration-dependent manner. Enzymatic activity was lost only in samples that were incubated with both tamoxifen and NADPH. The inactivation was characterized by a K(I) of 0.9 microM, a k(inact) of 0.02 min(-1), and a t(1/2) of 34 min. The loss in the 7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation activity did not result in a similar percentage loss in the reduced carbon monoxide spectrum, suggesting that the heme moiety was not the major site of modification. The activity of CYP2B6 was not recovered after removal of free tamoxifen using spin column gel filtration. The loss in activity seemed to be due to a modification of the CYP2B6 and not reductase because adding fresh reductase back to the inactivated samples did not restore enzymatic activity. A reconstituted system containing purified CYP2B6, NADPH-reductase, and NADPH-generating system was found to catalyze tamoxifen metabolism to 4-OH-tamoxifen, 4'-OH-tamoxifen, and N-desmethyl-tamoxifen as analyzed by high-performance liquid chromatography analysis. Preliminary studies showed that tamoxifen had no effect on the activities of CYP1B1 and CYP3A4, whereas CYP2D6 and CYP2C9 exhibited a 25% loss in enzymatic activity.  相似文献   
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