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This article considers the experiences of a Samoan female geographer undertaking community‐based field research in her home country, and identifies some lessons for researchers working in similar circumstances. The paper suggests that ethical behaviour in research is ‘place‐specific’, and there is therefore a need to employ culturally sensitive and ‘location‐specific’ methodologies when undertaking community‐based research fieldwork. For the lead researcher, growing up in Samoa played a significant role in gaining an understanding of a set of robust and effective procedures to evaluate citizens' resilience to climatic and other environmental challenges. Fluency in everyday and more formal local languages, and awareness of local differences, each with multi‐layered connections to local communities, understanding cultural nuances and practising respect for va tapuia [sacred space or relationships] protocols, together facilitated the process of knowledge acquisition and helped to confirm the validity of the conclusions derived from the study. 相似文献
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Sheep peripheral blood lymphocytes have been studied using a number of surface markers. Thus 16.6 ± 2.4% (mean ± S.E.) were surface immunoglobulin positive (sIg+) by direct immunofluorescence, 35.9 ± 2.1% formed Fc rosettes with bovine red blood cells (RBC) sensitized with rabbit antibody (Fc+) and 28.4 ± 2.0% formed rosettes with sheep red blood cells (RBC) in the presence of 4% dextran (DS+). The percentage of both Fc+ and DS+ lymphocytes tended to increase with age of the animals. Demonstration of these markers allowed computation of two further subpopulations: null cells lacking sIg and a receptor for sheep RBC, and Fc·null cells lacking a receptor for Fc and sheep RBC. The former population, which contained a proportion of Fc+ lymphocytes comprised 49.8 ± 3.8% of blood lymphocytes and the latter 38.4 ± 3.0%.Separation on nylon wool columns, selective rosette enrichment and depletion on density gradients and stimulation with phytomitogens have shown sIg+ and Fc+ lymphocytes to be nylon wool adherent and unresponsive to phytohaemagglutinin (PHA) and Concanavalin A (Con A) and DS+ lymphocytes to be nylon wool non-adherent and responsive to PHA and Con A. The data also indicates a major overlap of the lymphocyte subpopulations bearing sIg and Fc which are apparently B lymphocytes. Moreover these data support the contention that E-rosette formation with sheep RBC in the presence of dextran is a marker for sheep T cells. The data also indicates that Fc·null cells are T cells, eluting in the non-adherent fraction from nylon wool. It is probable that a proportion of these cells bear a SRBC receptor too weak for present detection methods. 相似文献
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Tasker S Binns SH Day MJ Gruffydd-Jones TJ Harbour DA Helps CR Jensen WA Olver CS Lappin MR 《The Veterinary record》2003,152(7):193-198
Blood samples from 426 healthy and sick cats in the UK were tested in a PCR assay for 'Candidatus Mycoplasma haemominutum' and Mycoplasma haemofelis (basonym Haemobartonella felis). Seventy-two of the cats (16.9 per cent) were positive for 'Candidatus M. haemominutum' alone, six (1.4 per cent) were positive for M. haemofelis alone and one (0.2 per cent) was positive for both. Logistic regression analysis indicated that older male cats were significantly more likely to be infected with 'Candidatus M. haemominutum', but there was no significant association between it and any of the haematological variables measured. M. haemofelis infection was uncommon in the anaemic cats sampled, and there were too few positive cases for multivariable analysis to be performed for M. haemofelis-positive status. 相似文献
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AIMS: To document infant feeding methods in the first six months of life in Xinjiang Uygur Autonomous Region, People's Republic of China, 2003-2004. Some problems with breast-feeding in the area are explained. METHODS: A longitudinal study of infant feeding practices was undertaken. A total of 1219 mothers who delivered babies during 2003 and 2004 were interviewed in five hospitals or institutes, and after discharge were contacted in person or by telephone at approximately monthly intervals to obtain details of infant feeding practices. Multivariate logistic regression analysis was used to explore factors associated with breast-feeding initiation. RESULTS: 'Any breast-feeding' rates at discharge and at 0.5, 1.5, 2.5, 3.5, 4.5 and 6 months were 92.2, 91.3, 89.9, 88.8, 87.7, 86.0 and 73.0%, respectively. 'Exclusive breast-feeding' rates at discharge and at 0.5, 1.5, 2.5, 3.5, 4.5 and 6 months were 66.2, 47.6, 30.1, 25.8, 22.1, 13.0 and 6.2%, respectively. The main problem of breast-feeding in Xinjiang was the early introduction of formula or water. The average duration of 'exclusive breast-feeding' was 1.8 months (95% confidence interval (CI) 1.7-2.0), of 'full breast-feeding' 2.8 months (95% CI 2.7-2.9) and of 'any breast-feeding' 5.3 months (95% CI 5.2-5.4). CONCLUSIONS: Infant feeding methods in Xinjiang were documented in this study and the main problems with infant feeding in Xinjiang are discussed. Further studies are needed to identify factors associated with 'exclusive breast-feeding' and duration. 相似文献