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11.
Ovine T-cell lines (including one clone [101A]), which are specific for Bluetongue virus serotype 1 (BTV1), have been established and characterized. Although these T-cell lines react with different isolates of BTV1 (including those from South Africa, Australia, Nigeria, and Cameroon), they do not react with heterologous BTV serotypes. Antigen specificity of these T-cells was studied using purified virus particles, infectious subviral particles (ISVP) and cores, or using individual BTV structural proteins that were either isolated by SDS-PAGE or expressed by recombinant strains of vaccinia virus. The results showed that each of the T-cell lines reacted with outer capsid protein VP2 (the BTV protein exhibiting most serotype-specific variation and the major neutralization antigen). However, all of the uncloned T-cell lines also reacted with either the core structural proteins or the outer capsid protein VP5. In contrast, the T-cell clone 101A only reacted with outer capsid protein VP2. Cell surface marker analysis showed that 101A has a helper T-cell phenotype (CD5+, CD4+, CD8-, T-19-). The T-cell lines and clone 101A all produced large amounts of interleukin 2 (IL-2) when stimulated with purified BTV1 virus particles, or with VP2 (up to 120 IU/ml from 2 x 10(5) T-cells). BTV serotype-specific antigenic sites, for B cells and at least one site for ovine helper T-cells, are therefore located within VP2.  相似文献   
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BACKGROUND: Depression is the most common mental health disorder in people aged over 65 years. Late-life depression is associated with chronic illness and disability. AIM: To investigate the feasibility of a collaborative care model for depression in older people in a primary care setting. DESIGN OF STUDY: Randomised controlled trial with 16-weeks follow up. SETTING: A primary care trust in Manchester. METHOD: Participants were 105 people aged 60 years or older who scored 5 or more on the Geriatric Depression Scale; 53 were randomly allocated to an intervention group and 52 to a usual care group. The intervention group received care managed by a community psychiatric nurse who delivered an intervention comprising a facilitated self-help programme with close liaison with primary care professionals and old-age psychiatry according to a defined protocol. The usual care group received usual GP care. A nested qualitative study explored the views of the health professionals and patients regarding the acceptability and effectiveness of the intervention. RESULTS: The main outcome measure was recovery from depression. Patients in the intervention group were less likely to suffer from major depressive disorder at follow up compared with usual care (0.32, 95% confidence = interval = 0.11 to 0.93, P = 0.036). The qualitative component of the study demonstrated the acceptability of the intervention to patients. CONCLUSION: A model of collaborative care for older people with depression, used in a primary care setting with a facilitated self-help intervention is more effective than usual GP care. This study demonstrates that the implementation of a collaborative care model is feasible in UK primary care and that the intervention is effective and acceptable to patients.  相似文献   
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Lifetime rates of psychiatric illness were compared in relatives of adolescent probands with bipolar I disorder and in relatives of age-matched schizophrenic controls. Familial aggregation of major affective disorders was observed in bipolar probands, the rate of bipolar I disorder greatly exceeding that reported in relatives of adult bipolar probands. Adolescent probands with childhood onset of psychiatric disturbance were distinguished from probands who had no premorbid childhood psychiatric abnormality in two ways: (1) significantly increased aggregation of bipolar I disorder in first-degree relatives; and (2) poorer antimanic response to lithium carbonate. These data underscore important heterogeneity in adolescent-onset bipolar disorder.  相似文献   
15.
Analyses of reassortant and parental strains of BTV serotypes 3 and 10, in serum neutralization tests, confirmed the major role of outer capsid protein VP2 in determination of virus serotype and its involvement in serum neutralization. However, a reassortant BTV strain (R70), containing protein VP5 derived from BTV 3 and VP2 derived from BTV 10, cross-neutralized with both parental virus strains (BTV 3 and BTV 10). It is concluded that VP5 also plays some part in serotype determination of these virus isolates, as analyzed by serum-neutralization, but its role may be less significant than that of VP2.  相似文献   
16.
FAS receptor (FAS, CD95) and FAS ligand (FAS-L, CD95-L) are complementary members of a particular apoptotic pathway that plays a major role in immune regulation. The activation of FAS-L may trigger cytotoxic mechanisms leading to the death of FAS-expressing cells. Tumor cells and tumor-infiltrating lymphocytes (TIL) may express FAS and FAS-L in various proportions, and their interplay may affect tumor behavior. In the present study, we explored the expression of FAS and FAS-L in 28 mammary carcinomas (19 ductal and 9 lobular) and in their lymph node metastases. The expression of these mediators in immunostained sections was graded and evaluated comparatively between normal and neoplastic mammary epithelium, between tumor cells and TILs, and between mammary carcinoma cells and their lymph node metastases. We demonstrated the coexpression of FAS and FAS-L by breast carcinoma cells and TIL, with FAS expressed more strongly by normal epithelial cells and TIL than tumor cells. FAS-L was better stained on tumor cells than on TIL. There was equal or greater expression of FAS and FAS-L in the primary tumors and their TIL than in the metastatic counterparts. Comparing the expression of FAS with that of FAS-L, we recorded FAS equal or stronger than FAS-L in the primary mammary tumors and the reversal of their expression, FAS-L greater than FAS in the lymph node metastases. These results are consistent with reports of studies with other tumors, suggesting that the upregulated FAS-L indicates an increased ability of tumor cells to induce apoptosis in TIL and in the normal tissues invaded. However, it is understood that the FAS/FAS-L system, although essential for apoptosis, is only a contributing factor to the complex process of tumor invasion and antitumor defense.  相似文献   
17.
The influence of 2-adrenoceptor antagonists in animal models of anxiety is quite inconsistent, with results spanning the full range of effect from anxiogenesis to anxiolysis. In the present study, an ethological technique was used to examine the effects of yohimbine (0.5–4.0 mg/kg) on plus-maze behaviour in DBA/2 mice. Results indicated significantanxiolytic-like effects on standard spatiotemporal measures at 2.0–4.0 mg/kg, and on risk assessment measures across the entire dose range. Full-scale follow-up studies with T1 and BALB/c strains confirmed that this action of yohimbine in the murine plus-maze is not peculiar to DBA/2 mice. The more selective 2-adrenoceptor antagonist, idazoxan (0.63–5.0 mg/kg), exerted much weaker behavioural effects in the maze while the 2-adrenoceptor agonist, clonidine (0.01–0.1 mg/kg), produced a profile consistent with non-specific behavioural disruption. Data are discussed in relation to the possible involvement of 5-HT1A receptor mechanisms in the observed anxiolytic-like effects of yohimbine in the murine plus-maze.  相似文献   
18.
Liver disease in Europe   总被引:1,自引:0,他引:1  
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Registered dietitians (RDs) and dietetic technicians, registered (DTRs) can implement environmentally responsible practices in their workplace and personal lives. RDs and DTRs who conserve natural resources while minimizing environmental degradation will help maintain sustainability of the food system, which requires knowledge of the external costs of operational and personal decisions. These external costs include energy to produce, transport, and process food; water for food production, preparation, and sanitation; removal of air pollutants; and waste management. As client and public educators, RDs and DTRs are uniquely positioned to meet the growing needs of those seeking guidance on food choices as they relate to ecological sustainability. In an effort to promote ecologically sustainable diets, it is important to consider natural resources as they relate to food production, transformation, distribution, access, and consumption. It is essential that the dietetics community takes a more active leadership role in support of ecological sustainability and social responsibility. RDs and DTRs can influence policy at the institutional, community, local, state, and national levels by presenting results of operational practices and science-based natural resource information. RDs and DTRs are encouraged to become educated and active in implementing sustainable practices and shaping policy in an effort to promote healthier individuals, communities, and the nation as a whole.  相似文献   
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