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A review of studies of parent-child communication about sexuality and HIV/AIDS in sub-Saharan Africa
Parent-child sexuality communication has been identified as a protective factor for adolescent sexual and reproductive health, including HIV infection. The available literature on this topic in sub-Saharan Africa is increasing; however a systematic review of studies has not been conducted. This article reviews the literature in the area of parental or caregiver and child communication about sexuality and HIV/AIDS in sub-Saharan Africa. A review of peer reviewed literature published between 1980 and April 2011 was conducted. Communication process studies investigating the frequency, content, style, tone of discussions, preferences, as well as associations with and barriers to sexuality communication are reviewed. In addition, studies which examine behavioral associations with parent-child sexuality communication, and intervention studies to improve parent-child sexuality communication are examined. The findings from process studies suggest wide variation in terms of frequency of discussions, with a range of socio-demographic and other factors associated with sexuality communication. Overall, findings demonstrate that discussions tend to be authoritarian and uni-directional, characterized by vague warnings rather than direct, open discussion. Moreover, parents and young people report a number of barriers to open dialogue, including lack of knowledge and skills, as well as cultural norms and taboos. Findings are less clear when it comes to associations between parental communication and adolescent sexual activity and contraception use. However, nascent indications from intervention research suggest positive findings with increases in frequency and comfort of discussions, among other outcomes. Gaps in the research are identified and discussed with implications for future studies. 相似文献
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Benefits of targeting both pericytes and endothelial cells in the tumor vasculature with kinase inhibitors 总被引:45,自引:0,他引:45
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Bergers G Song S Meyer-Morse N Bergsland E Hanahan D 《The Journal of clinical investigation》2003,111(9):1287-1295
Functions of receptor tyrosine kinases implicated in angiogenesis were pharmacologically impaired in a mouse model of pancreatic islet cancer. An inhibitor targeting VEGFRs in endothelial cells (SU5416) is effective against early-stage angiogenic lesions, but not large, well-vascularized tumors. In contrast, a kinase inhibitor incorporating selectivity for PDGFRs (SU6668) is shown to block further growth of end-stage tumors, eliciting detachment of pericytes and disruption of tumor vascularity. Importantly, PDGFRs were expressed only in perivascular cells of this tumor type, suggesting that PDGFR(+) pericytes in tumors present a complimentary target to endothelial cells for efficacious antiangiogenic therapy. Therapeutic regimes combining the two kinase inhibitors (SU5416 and SU6668) were more efficacious against all stages of islet carcinogenesis than either single agent. Combination of the VEGFR inhibitor with another distinctive kinase inhibitor targeting PDGFR activity (Gleevec) was also able to regress late-stage tumors. Thus, combinatorial targeting of receptor tyrosine kinases shows promise for treating multiple stages in tumorigenesis, most notably the often-intractable late-stage solid tumor. 相似文献
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Activation of the CPP32 protease in apoptosis induced by 1-beta-D- arabinofuranosylcytosine and other DNA-damaging agents 总被引:2,自引:0,他引:2
The response of human myeloid leukemia cells to treatment with 1-beta- arabinofuranosylcytosine (ara-C) includes the induction of apoptosis. Ara-C induced apoptosis is associated with proteolytic cleavage of poly(ADP-ribose) polymerase (PARP) and protein kinase C (PKC) delta. However, the signals involved in this response are unknown. The present studies show that ara-C treatment of U-937 cells is associated with induction of a protease activity that cleaves the tetrapeptides Ac-DEVD- pNA and Ac-DMOD-pNA found at the cleavage sites of PARP and PKC delta, respectively. The ara-C-induced protease activity was sensitive to overexpression of the anti-apoptotic protein Bcl-xL and the baculovirus protein p35. By contrast, overexpression of the cowpox virus protein CrmA blocked apoptosis induced by engagement of the Fas receptor but not that induced by ara-C. CrmA overexpression also had no detectable effect on ara-C-induced cleavage of PKC delta. The results further show that ara-C induces activation of the CPP32 protease by a CrmA- insensitive and p35-sensitive mechanism. Similar results were obtained with cisplatinum, etoposide, and camptothecin. These findings indicate that ara-C and other DNA-damaging agents activate a CrmA-insensitive apoptotic pathway involving CPP32 and that these signals differ from those associated with apoptosis induced by the Fas receptor. 相似文献
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Krekel NM van Amerongen AH Bergers E Meijer S van den Tol P 《Nederlands tijdschrift voor geneeskunde》2012,156(10):A4173
Breast-conserving surgery for palpable mammary tumours is usually guided by palpation. It appears, however, that identifying tumour margins only by palpation can be problematic, resulting in less than optimal effectiveness of this type of operation. The use of ultrasonography is a simple and non-invasive way of facilitating real-time localisation of breast carcinoma during surgery so that a tumour can be excised with controlled precision. Ultrasound is used to localise the tumour prior to surgery; its location is subsequently marked on the skin. During tissue dissection, ultrasound can be used to inspect the location and depth of the tumour as well as determining whether the tumour's surrounding margins are sufficient, thereby preventing the unnecessary removal of healthy tissue. Ultrasound can be used again after the excision to verify that the tumour was indeed radically removed. The efficacy of ultrasonically guided surgery for palpable mammary tumours is currently being studied in a prospective, randomised, multicentre trial. 相似文献
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Guidelines for international collaborative research 总被引:2,自引:1,他引:1
OBJECTIVE: As the global village becomes a reality, there is an increasing
need to conduct international collaborative studies in family practice. A
workshop at the WONCA meeting in Hong Kong used international attendees to
produce a set of guidelines for international research. METHODS: At the
workshop four completed international projects, each using a different
strategy, were presented so that common themes might become apparent. The
themes were then discussed and guidelines emerged from the process.
RESULTS: Seven guidelines emerged for consideration before embarking on an
international collaborative research project in family medicine. The
guidelines deal with the characteristics of the research question and the
importance of communication. The need for simple, brief methods of data
collection, funding and pilot testing were identified. CONCLUSION: The
question must be relevant to all participants to maintain interest and
measurement tools must be validated to understand the impact of cultural
differences in understanding.
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