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In a multi-site study of vaginal microbicide acceptability conducted with sexually active young women, quantitative assessments revealed significant differences in acceptability by site. Participants in Puerto Rico rated the gel more favourably than mainland US participants in terms of liking the gel and likelihood of future use. To explain these differences, we examined responses to qualitative behavioural assessments. Young women in mainland USA associated gel leakage with uncomfortable sensations experienced during menstruation, while young women in Puerto Rico had positive associations of gel use with douching. These negative or positive associations affected assessments of the gel's physical qualities. In addition, young women's perceptions of primary partners' support for microbicide use influenced sexual satisfaction with the gel and, ultimately, product acceptability. Finally, geographic HIV-risk context contributed to heightened HIV-risk perception, which influenced likelihood of future microbicide use, even for women in stated monogamous relationships. Future microbicide acceptability studies should take into account potential differences in acceptability by site such as HIV-risk perception based on local HIV prevalence, popularity of vaginal hygiene products in a specific area and male attitudes in different cultures concerning women's use of HIV protection strategies.  相似文献   
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PurposeThe use of self-report of human papillomavirus (HPV) vaccination status has several implications for clinical care and research. Reports of HPV vaccination history of adolescent girls (ages: 14–17 years) and their mothers were compared with medical chart data to assess the accuracy of HPV vaccine recall.MethodsAdolescent girls (N = 74) and their mothers independently completed questionnaires regarding HPV vaccination history, which were compared with medical chart data to assess the accuracy of HPV vaccine recall.ResultsThere were high levels of inaccuracy between actual HPV vaccination and self-report of vaccine receipt. Both mothers and daughters had poor recall of HPV vaccination, and were more likely to underestimate than overestimate the coverage. Girls who accurately reported their vaccination status were not more likely to have been sexually active in the past 2 months (p = .75).ConclusionsThese findings have clinical and research implications, as self-report is relied on to assess young women's vaccination status in research settings or in the absence of medical records. These data address the still prevalent concern that HPV vaccination encourages adolescent sexual behavior. It is unlikely that sexual behaviors will change as a result of vaccination in the large percentage of girls who cannot recall being vaccinated.  相似文献   
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Restriction endonuclease mapping analyses were made of DNA from a few members of a Macedonian family with hematological characteristics of delta beta-thalassemia, ie, microcytosis, normal HbA2 levels, and elevated levels of HbF (7% to 14%) with G gamma (average 40.5%) and A gamma T chains (average 59.5%). A large deletion of 18 to 23 kb was present with a 5' breakpoint within a 670-bp segment of DNA between the HpaI and NcoI restriction sites 5' to the delta globin gene, and a 3' breakpoint between the BamHI and HpaI restriction sites located some 9 to 13 kb 3' to the beta globin gene. This deletion is different from those present in other types of G gamma A gamma(delta beta)zero- thalassemia. The similarity of the hematological expression of these delta beta-thalassemic conditions which have somewhat comparable 5' breakpoints supports the idea that an important fetal hemoglobin- controlling region lies between the psi beta and delta globin genes.  相似文献   
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Heaton  DC; Fitzgerald  PH; Fraser  GJ; Abbott  GD 《Blood》1981,57(5):883-887
A newborn without any signs of Down's syndrome was found to have an acute proliferation that remitted without drug therapy. Chromosomal analysis of blood, bone marrow, and skin cells revealed that the child was a constitutional mosaic with normal cells and a low number of cells in which one no. 21 chromosome was replaced by a probably isochromosome for the no. 21 long arm: 46,XY/46,XY,i(21q). The abnormal cell line of the mosaic appeared to be selectively involved in this proliferation.  相似文献   
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Ninety-four consecutive patients with chronic myelogenous leukemia in first clinical chronic phase, median age of 34.0 years (range, 6.8 to 52.4 years), with a histocompatible sibling donor, were treated with fractionated total body irradiation (1,320 cGy) and high-dose etoposide (60 mg/kg) followed by allogeneic bone marrow transplantation (BMT). The median time from diagnosis to BMT was 7.0 months (range, 2.3 to 72.0 months). Sixty patients were treated before BMT with hydroxyurea alone, four patients with busulfan alone, one patient with interferon alone, and the other 29 patients were treated with various combinations of these drugs. Cumulative probabilities of overall survival, event- free survival, and relapse at 5 years were 73%, 64%, and 14%, respectively. The median follow-up time for surviving patients was 38 months, ranging from 12 to 88 months. By stepwise Cox regression analysis, significant prognostic variables were age at transplant, acute graft-versus-host disease > or = grade II, cytomegalovirus- associated interstitial pneumonitis, and years from diagnosis to BMT.  相似文献   
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评价无支架异种生物瓣膜主动脉瓣替换术后2年左室功能的变化。将80例同期施行主动脉瓣替换病人分为2组,50例(年龄69.3±9.3岁)应用TorontoSPVTM瓣;30例(年龄71.6±7.7岁)作为对照组接受支架人工瓣膜替换。术前、术后1、6、12及24个月间记录M型及Doppler超声心动图,采用计算机图像数字分析,定量测定左室功能的变化。随访期间,Toronto组主动脉瓣跨瓣压差为0.8±0.6kPa(6.0±4.5mmHg),明显低于对照组2.3±0.9kPa(17.3±6.8mmHg);术后1个月,左室心肌质量下降25%,左室+Vcf及-Vcf明显增加(2.0±0.8/1.4±0.3s-1,P<0.01;2.8±1.2/1.8±0.7s-1,P<0.01)。术后6个月,左室功能进一步改善,心室肥厚的消退更趋完全,该变化在其后的随访期间保持稳定。结论:与支架瓣膜相比,无支架异种生物瓣膜具有较大瓣口开放面积及低跨瓣压差,这促进了术后左室功能的恢复及病理性肥厚的逆转  相似文献   
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