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A needs assessment survey of ethics review committees (ERCs) across Africa was conducted in order to establish their major needs and areas of weaknesses in terms of ethical review capacity. The response rate was 84% (31 of 37 targeted committees), and committees surveyed were located in 18 African countries. The majority of the responding committees (61%) have been in existence between 5 and 10 years; approximately 74% of the respondents were institutional committees, with the remainder being either national (6/31) or regional (2/31).
In terms of the ethical review process, nine of the 31 committees that responded did not have standard operating procedures (SOPs), and seven of the 22 that did have SOPs had never revised them after their initial development (an average period of three years). Of the 31 committees, 10 operated without any ethical guidelines. Many of the committees (13/30) met once per month, and the number of proposals reviewed annually varied, ranging from five to over 100. All respondents relied on paper-based data management and archiving systems.
Overall, the survey identified the major constraints on ERCs as lack of office equipment, outdated or lack of SOPs, lack of electronic data management systems, inadequate resources, lack of or insufficient expertise on the committees, and poor recognition of the importance of the role of the committees. Consequently, the authors are addressing the identified needs and weaknesses through the Bill and Melinda Gates Foundation-funded capacity building project. The impact of the intervention project will be assessed during and at the end of the four-year longitudinal project.  相似文献   
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Patterns and mechanisms of short‐term temperature acclimation and long‐term climatic adaptation of respiration among intraspecific populations are poorly understood, but both are potentially important in constraining respiratory carbon flux to climate warming across large geographic scales, as well as influencing the metabolic fitness of populations. Herein we report on leaf dark respiration of 33‐year‐old trees of jack pine (Pinus banksiana Lamb.) grown in three contrasting North American common gardens (0.9, 4.6, and 7.9 °C, mean annual temperature) comprised of identical populations of wide‐ranging geographic origins. We tested whether respiration rates in this evergreen conifer acclimate to prevailing ambient air temperatures and differ among populations. At each of the common gardens, observed population differences in respiration rates measured at a standard temperature (20 °C) were comparatively small and largely unrelated to climate of seed‐source origin. In contrast, respiration in all populations exhibited seasonal acclimation at all sites. Specific respiration rates at 20 °C inversely tracked seasonal variation in ambient air temperature, increasing with cooler temperatures in fall and declining with warmer temperatures in spring and summer. Such responses were similar among populations and sites, thus providing a general predictive equation regarding temperature acclimation of respiration for the species. Temperature acclimation was associated with variation in nitrogen (N) and soluble carbohydrate concentrations, supporting a joint enzyme and substrate‐based model of respiratory acclimation. Regression analyses revealed convergent relationships between respiration and the combination of needle N and soluble carbohydrate concentrations and between N‐based respiration (RN, μmol mol N? 1 s? 1) and soluble carbohydrate concentrations, providing evidence for general predictive relationships across geographically diverse populations, seasons, and sites. Overall, these findings demonstrate that seasonal acclimation of respiration modulates rates of foliar respiratory carbon flux in a widely distributed evergreen species, and does so in a predictable way. Genetic differences in specific respiration rate appear less important than temperature acclimation in downregulating respiratory carbon fluxes with climate warming across wide‐ranging sites.  相似文献   
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We report two cases of primary carcinoma of the ovary in which 'ciliated' adenocarcinoma cells were found in the ascitic fluid. Transmission electron microscopy revealed that these were not true cilia but rather a prolific growth of abnormal microvilli. The cytological findings were compared with the histological appearances of the primary tumour. No ciliated cells were seen in the primary tumour, suggesting that the formation of the microvilli represented an independent proliferation of the cells in the fluid. Special staining reactions for mucin, alkaline phosphatase and epithelial membrane antigen were identical in the primary tumour and the cells in the ascitic fluid.  相似文献   
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