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排序方式: 共有643条查询结果,搜索用时 15 毫秒
91.
Cornberg M Chen AT Wilkinson LA Brehm MA Kim SK Calcagno C Ghersi D Puzone R Celada F Welsh RM Selin LK 《The Journal of clinical investigation》2006,116(5):1443-1456
Why some virus-specific CD8 TCR repertoires are diverse and others restricted or "oligoclonal" has been unknown. We show here that oligoclonality and extreme clonal dominance can be a consequence of T cell cross-reactivity. Lymphocytic choriomeningitis virus (LCMV) and Pichinde virus (PV) encode NP(205-212) epitopes that induce different but highly cross-reactive diverse TCR repertoires. Homologous viral challenge of immune mice only slightly skewed the repertoire and enriched for predictable TCR motifs. However, heterologous viral challenge resulted in a narrow oligoclonal repertoire with dominant clones with unpredictable TCR sequences. This shift in clonal dominance varied with the private, i.e., unique, specificity of the host's TCR repertoire and was simulated using affinity-based computer models. The skewing differences in TCR repertoire following homologous versus heterologous challenge were observed within the same private immune system in mice adoptively reconstituted with memory CD8 T cell pools from the same donor. Conditions driving oligoclonality resulted in an LCMV epitope escape variant in vivo resembling the natural Lassa virus sequence. Thus, T cell oligoclonality, including extremes in clonal dominance, may be a consequence of heterologous immunity and lead to viral escape. This has implications for the design of peptide-based vaccines, which might unintentionally prime for skewed TCR responses to cross-reactive epitopes. 相似文献
92.
OBJECTIVE: The aim of this study was to determine the prevalence of life-threatening arrhythmias in monitored ED patients while in the radiology suite. METHODS: This is a retrospective analysis at a tertiary care hospital with an ED census of 52,000 visits. The patient population consisted of 3,051 adult ED patients with a chief complaint of chest pain, who were monitored with telemetry while they were sent to the radiology suite, and who were ultimately admitted to the hospital. RESULTS: Of a total of 3,051 consecutive patients with a cardiac presentation who received a nonportable chest x-ray, no patients were found to have incurred a life-threatening arrhythmia while in the radiology suite. CONCLUSION: The prevalence of a cardiac arrhythmia occurring during transport or while within the radiology suite in our study was zero. We conclude that stable patients can probably be transported to radiology safely without the use of bedside telemetry. 相似文献
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94.
Lin Y Huybrechts I Vandevijvere S Bolca S De Keyzer W De Vriese S Polet A De Neve M Van Oyen H Van Camp J De Backer G De Henauw S 《The British journal of nutrition》2011,105(11):1692-1703
The objectives of the present study were to assess total dietary fibre intake and the main contributors to fibre intake in the Belgian population by sex-age and sex-education groups and to investigate its relationship with BMI and waist circumference (WC). The participants of the Belgian food consumption survey (2004) were randomly selected. Information about food intake was collected using two repeated, non-consecutive 24 h recall interviews. A total of 3083 individuals ( ≥ 15 years; 1546 men and 1537 women) completed both interviews. The main contributors to total fibre intake (17·8 g/d) were cereals and cereal products (34 %; 5·9 g/d), potatoes and other tubers (18·6 %; 3·3 g/d), fruits (14·7 %; 2·8 g/d) and vegetables (14·4 %; 2·6 g/d). Legume fibre intake was extremely low (0·672 %; 0·139 g/d). In all sex-age and sex-education groups, total fibre intake was below the recommendations of the Belgian Superior Health Council. Men (21 g/d) consumed significantly more fibre than women (17·3 g/d) (P < 0·001). Lower educated men and higher educated women reported the highest fibre intake. A significant inverse association was found between total fibre intake and WC (β = - 0·118, P < 0·001). Fruit-derived fibre was positively associated with WC (β = 0·731, P = 0·001). In summary, total fibre intake was inversely associated with WC, whereas fruit-derived fibre intake was positively associated with WC in the Belgian population. 相似文献
95.
Lin Y Bolca S Vandevijvere S De Vriese S Mouratidou T De Neve M Polet A Van Oyen H Van Camp J De Backer G De Henauw S Huybrechts I 《The British journal of nutrition》2011,105(7):1106-1116
The objective of the present study was to assess animal and plant protein intakes in the Belgian population and to examine their relationship with overweight and obesity (OB). The subjects participated in the Belgian National Food Consumption Survey conducted in 2004. Food consumption was assessed by using two non-consecutive 24?h dietary recalls. About 3083 participants (?≥?15 years of age; 1546 males, 1537 females) provided completed dietary information. Animal protein intake (47?g/d) contributed more to total protein intakes of 72?g/d than plant protein intake, which accounted for 25?g/d. Meat and meat products were the main contributors to total animal protein intakes (53?%), whereas cereals and cereal products contributed most to plant protein intake (54?%). Males had higher animal and plant protein intakes than females (P?0·001). Legume and soya protein intakes were low in the whole population (0·101 and 0·174?g/d, respectively). In males, animal protein intake was positively associated with BMI (β?=?0·013; P?=?0·001) and waist circumference (WC; β?=?0·041; P?=?0·002). Both in males and females, plant protein intake was inversely associated with BMI (males: β?=?-?0·036; P?0·001; females: β?=?-?0·046; P?=?0·001) and WC (male: β?=?-?0·137; P?0·001; female: β?=?-?0·096; P?=?0·024). In conclusion, plant protein intakes were lower than animal protein intakes among a representative sample of the Belgian population and decreased with age. Associations with anthropometric data indicated that plant proteins could offer a protective effect in the prevention of overweight and OB in the Belgian population. 相似文献
96.
Studies on violence in the work of security guards are largely lacking. This study is unique in that it focuses on security guards (n=1,010) in Finland, and assesses the different forms, prevalence, and risk factors of the work-related violence they often face. Information to a survey instrument was obtained by first interviewing 30 volunteers. Then we made a cross-sectional mailed survey that was sent to a randomized group of 2,000 security guards. The response rate was 52. We found the prevalence of verbal aggression, threats of assault, and physical acts against security guards at least once a month to be 39%, 19%, and 15% respectively. As regards risk factors and who is most at risk, our results show that male gender, young age, low work experience, late working hours, and time pressure were associated with all three forms of work-related violence. Unlike other forms of violence, verbal aggression was highly prevalent outside the metropolitan area and directed towards both more and less experienced security guards. In prevention policies for violence, it is important to identify high-risk groups such as those who have less work experience. 相似文献
97.
98.
AbstractIn the field of alcohol, drug, tobacco, and gambling studies, empirical research on the barriers and facilitators for public prevention policies has been scarce. Public policy studies show that the implementers of different organizational positions impact on policy implementation. In this paper, the barriers and facilitators for the implementation of an integrated national policy for addiction prevention, as seen from the positions of managers, prevention specialists, and frontline workers, are analyzed on the basis of qualitative interview data. The results indicate that the managers were structurally oriented in their thinking and emphasized local structures as facilitators. All the groups saw prevention as underfunded and undervalued. The specialists were most focused on the official structures and regarded the functioning of the structures as a key facilitator. The frontline workers underlined that their position was a facilitator in itself, offering a unique viewpoint to the localities and to the lives of their clients. A key finding is also the normalcy of gambling that both the specialist and frontline workers regarded as a major barrier. The results show that studying the policy implementation context is important: it makes it possible to understand social and cultural factors that can function as barriers or facilitators. 相似文献
99.
100.