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41.
Reported parameters of the MTT assay vary widely, and reflect a need to optimise the assay for different cell types. The MTT assay conditions for the human B-lymphocyte-derived cell line WIL2NS were optimised for MTT incubation and formazan development. The optimised MTT assay was validated by examining the effects of the acaride amitraz on WIL2NS. In pH-buffered media in the absence of cells, MTT formed formazan spontaneously, and absorbance was proportional to both the initial concentration of MTT and the time of incubation at 37 °C. One milligram per millilitre MTT was toxic to WIL2NS cells, but the accuracy of the standard curve was reduced when only 0.2 mg/ml MTT was used. Twenty percent SDS in 0.2 M HCl was preferable to DMSO as a solvent for formazan. Exposure to 0.035% amitraz resulted in a significant reduction in WIL2NS cell numbers after only 2 h of exposure. It was concluded that 0.035% of amitraz has the potential to adversely affect lymphocytes in the systemic blood system in humans, and that an optimised MTT assay was obtained by incubating WIL2NS cells with 0.45 mg/ml MTT for 17 h, followed by addition of acidified SDS for 1 h.  相似文献   
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Healthy Start is the UK government's food voucher programme for low‐income pregnant women and young children. It was introduced in 2006, but the impact of the programme on nutritional outcomes remains understudied. This study sought to explore potential outcomes of the Healthy Start programme (including intended and unintended outcomes) and develop explanations for how and why these outcomes might occur. A realist review preceded this study, in which programme theories were developed and tested using existing evidence. This qualitative study aimed to further refine and consolidate the programme theories from the realist review while remaining open to new and emerging theories (or hypotheses) about how low‐income pregnant women use Healthy Start vouchers. Semistructured interviews were conducted with 11 low‐income women from North West England, who received Healthy Start vouchers during pregnancy. A realist logic of analysis was applied to generate clear and transparent linkages between outcomes and explanations. The findings suggested that some women used the vouchers to improve their diets during pregnancy (intended outcome), whereas some women were diverted towards alternative or unintended outcomes. Women's circumstances, values, beliefs, and motivations influenced how they perceived and responded to the vouchers. This paper presents four evidence‐based programme theories to explain four contrasting (and potentially overlapping) outcomes: dietary improvements (theory refined from review), shared benefits (new theory), financial assistance (theory refined from review), and stockpiling formula (new theory). It considers how the Healthy Start programme could be improved, to increase the possibilities for low‐income women to experience the intended outcome of dietary improvements.  相似文献   
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IntroductionThe Bombay phenotype is a rare blood group determined by the absence of H antigens. Bombay individuals produce anti-H, a clinically significant antibody that react against all ABO blood group. Anti-H can mask underlying alloantibody during antibody investigation, a challenge in current transfusion practice. The aim of this article is to explore saliva inhibition, a novel method to detect underlying alloantibody in Bombay individuals.Case PresentationThe case is a 93-year-old female transfused with pre-donated autologous blood for a surgery. We determined anti-H subclass and thermal amplitude, secretor status, and optimal ratio of saliva and Bombay plasma. Plasma samples containing anti-H were spiked with anti-Fy(a) to determine the effectiveness of saliva inhibition in uncovering underlying alloantibodies.ResultsAnti-H was confirmed to be predominately IgM with broad thermal amplitude. Tube immediate spin (IS) showed stronger anti-H reactivity compared to column agglutination technology (CAT). Spiked anti-Fy(a) was successfully detected using saliva inhibition method.ConclusionTube IS appears more sensitive to anti-H. Saliva inhibition appears to be a promising method to detect underlying alloantibody in the plasma of Bombay phenotype individuals.  相似文献   
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OBJECTIVE: To explore the extent and impact of professional boundary crossings in metropolitan, regional and rural mental health practice in Victoria and identify strategies mental health clinicians use to manage dual relationships. METHOD: Nine geographically located focus groups consisting of mental health clinicians: four focus groups in rural settings; three in a regional city and two in a metropolitan mental health service. A total of 52 participants were interviewed. RESULTS: Data revealed that professional boundaries were frequently breached in regional and rural settings and on occasions these breaches had a significantly negative impact. Factors influencing the impact were: longevity of the clinician's relationship with the community, expectations of the community, exposure to community 'gossip' and size of the community. Participants reported greater stress when the boundary crossing affected their partner and/or children. Clinicians used a range of proactive and reactive strategies, such as private telephone number, avoidance of social community activities, when faced with a potential boundary crossing. The feasibility of reactive strategies depended on the service configuration: availability of an alternative case manager, requirement for either patient or clinician to travel. The greater challenges faced by rural and regional clinicians were validated by metropolitan participants with rural experience and rural participants with metropolitan experience. CONCLUSIONS: No single strategy is used or appropriate for managing dual relationships in rural settings. Employers and professional bodies should provide clearer guidance for clinicians both in the management of dual relationships and the distinction between boundary crossings and boundary violation. Clinicians are clearly seeking to represent and protect the patients' interests; consideration should be given by consumer groups to steps that can be taken by patients to reciprocate.  相似文献   
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