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81.
To facilitate the design of effective policies that can address adolescent's reproductive health problems, it is necessary to gain a thorough understanding of patterns of adolescents' sexual behavior, and the factors that affect them. Using a unique set of data collected in 2004 from a nationally-representative survey of adolescents, this study examines adolescents' risky and protective sexual behavior in Burkina Faso. Findings show that 11% of adolescent males had sexual intercourse in last twelve months with more than two partners but did not use condoms. Logistic regression analysis shows that the odds of using condoms increased with years of schooling and self-efficacy in use of condoms. Females who were very confident of getting a male partner to wear a condom were six times more likely to have used a condom at last sex than those who were not confident at all.  相似文献   
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Background: Metastatic breast cancer is generally believed to be associated with a poor prognosis. Therapeutic advances over the past two decades, however, have resulted in improved outcomes for selected patients with limited metastatic disease. Methods: Between March 1991 and October 2002, 31 patients had hepatic resection for breast cancer metastases limited to the liver. Clinical and pathologic data were collected prospectively from breast and hepatobiliary databases. Results: Median age of patients was 46 years (range, 31 to 70). Liver metastases were solitary in 20 patients and multiple in 11 patients. Median size of the largest liver metastasis was 2.9 cm (range, 1 to 8). Major liver resections (three or more segments resected) were performed in 14 patients, whereas minor resections (fewer than three segments resected) with or without radiofrequency ablation (RFA) were performed in 17 patients. No postoperative mortality occurred. Of the 31 patients, 27 (87%) received either preoperative or postoperative systemic therapy as treatment for metastatic disease. The median survival was 63 months; a single patient died within 12 months of hepatic resection. The overall 2- and 5-year survival rates were 86% and 61%, respectively, whereas the 2- and 5-year disease-free survival rates were 39% and 31%, respectively. No treatment- or patient-specific variables were found to correlate with survival rates. Conclusions: In selected patients with liver metastases from breast cancer, an aggressive surgical approach is associated with favorable long-term survival. Hepatic resection should be considered a component of multimodality treatment of breast cancer in these patients.  相似文献   
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Accurate age determination is fundamental in both forensic medicine and anthropology. Many methods that relate dental characteristics to adult age have been proposed, but there is still no simple and reliable method that does not damage the study material. The aim of this work was to propose a relevant and practical technique for determining age in adults that could be used in both living and deceased individuals. The sample was composed of 210 CT scans from individuals aged from 15 to 85 years old, with four healthy canines present in the mouth. The 840 canines were modelled using Mimics® 10.01 software. The pulp volume/total volume ratio ×100 was determined for each tooth. Seven mathematical models, corresponding to all possible real situations, were determined by the weighted least squares method and ranked in order of relative performance. The adequacy of the seven models to the data was very high with the regressions proposed (0.915?<?R 2 adjusted?<?0.964). Ranked in order of performance, the maxillary model was the most powerful of the seven models for age determination, followed by the 4 canines model, the 13 model and the 23 model.  相似文献   
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In this study, we target arginine auxotrophy of AML cell lines using human arginase I cobalt-PEG5000. HuArgI(Co)-PEG5000 was cytotoxic to all AML cell lines tested. Mononuclear cells and CD34+ blasts were not sensitive demonstrating the selectivity of HuArgI(Co)-PEG5000-induced arginine deprivation. Addition of l-citrulline led to the rescue of five cell lines. The four cell lines that were not rescued by l-citrulline did not express argininosuccinate synthetase-1, indicating complete arginine auxotrophy. Inhibition of autophagy increased cell sensitivity to HuArgI(Co)-PEG5000 demonstrating the protective role of autophagy following arginine deprivation.  相似文献   
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Mobile health (mHealth) interventions to promote antiretroviral therapy (ART) adherence have shown promise; however, among persons living with HIV who abuse methamphetamine (MA), effective tailoring of content to match the expressed needs of this patient population may be necessary. This study aimed (1) to understand patient perspectives of barriers and facilitators of ART adherence among people with HIV who use MA, and (2) to obtain feedback on the thematic content of an mHealth intervention in order to tailor the intervention to this subgroup. Two separate focus groups, each with 10 HIV+/MA+ individuals, were conducted. Transcribed audio recordings were qualitatively analyzed to identify emergent themes. Inter-rater reliability of themes was high (mean Kappa = .97). Adherence barriers included MA use, misguided beliefs about ART adherence, memory and planning difficulties, social barriers and perceived stigma, and mental heath issues. Facilitators of effective ART adherence were cognitive compensatory strategies, promotion of well-being, health-care supports, adherence education, and social support. Additionally, the focus groups generated content for reminder text messages to be used in the medication adherence intervention. This qualitative study demonstrates the feasibility of using focus groups to derive patient-centered intervention content to address the health challenge at hand in targeted populations.  相似文献   
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National HIV prevalence estimates across sub-Saharan Africa range from less than 1 percent to over 25 percent. Recent research proposes several explanations for the observed variation, including prevalence of male circumcision, levels of condom use, presence of other sexually transmitted infections, and practice of multiple concurrent partnerships. However, the importance of partnership concurrency for HIV transmission may depend on how it affects coital frequency with each partner. The coital dilution hypothesis suggests that coital frequency within a partnership declines with the addition of concurrent partners. Using sexual behavior data from rural Malawi and urban Kenya, we investigate the relationship between partnership concurrency and coital frequency, and find partial support for the coital dilution hypothesis. We conclude the paper with a discussion of our findings in light of the current literature on concurrency.  相似文献   
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