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91.
Footrot is a contagious disease of small ruminants which is caused by the bacterium Dichelobacter nodosus. In its virulent form there are severe economic losses and a very significant animal welfare issue. Sheep and goats can be vaccinated for treatment and prevention of the disease. There are 10 different serogroups of D. nodosus (A–I and M) and immunity is serogroup-specific. When all 10 serogroups are presented together in a vaccine, protection persists for only a few months due to “antigenic competition”. Consequently we evaluated the use of sequential monovalent or bivalent vaccines to control/eliminate/eradicate virulent footrot in a longitudinal intervention study on 12 commercial farms in southeast Australia with flock sizes of approximately 1200–4200 sheep. Overall, virulent footrot was eradicated from 4 of the flocks, 2 of which had 2 serogroups, and the others 4 or 5 serogroups. Where there were only 1 or 2 serogroups (3 farms) the clinical response was rapid and dramatic; prevalence was reduced from 45 to 50% before vaccination to 0% (2 farms) or 0.4% (1 farm) after one round of vaccination. In the remaining 9 flocks there were more than 2 serogroups and successive bivalent vaccines were administered leading to eradication of virulent footrot on 2 farms over 4 years and control of the disease on all but 3 of the others. Of the latter farms, 1 discontinued, and 2 initially had poor response to vaccine due to misdiagnosis of serogroup ‘M’, which was previously unknown in Australia. Control was achieved after administration of a serogroup M vaccine. These results provide clear evidence for control, elimination and eradication of virulent footrot by outbreak-specific vaccination in Australia.  相似文献   
92.
This randomized clinical trial employed a 2-group (general child behavior management training vs. distraction for pain management training) design across repeated parent-administered needle procedures. Forty-seven children with a chronic illness requiring recurrent injections were observed at baseline and 2 intervention sessions. Videotaped observations of parent–child interactions were coded for child behavioral distress and parents' use of behavior management strategies. Across groups, many children displayed minimal to no distress at baseline. Among participants with significant distress, neither intervention group displayed consistently decreased procedural distress or increased use of child behavior management strategies.  相似文献   
93.
Researchers examined the sun-protective intentions and behavior of young, Caucasian, Australian sportswomen aged between 17 and 35 years (N?=?100). The study adopted a 2 x 2 experimental design, comparing group norms (supportive vs. non-supportive) and image norms (tanned vs. pale) related to sun protection and taking into account group identification with friends and peers in the sport. While no significant findings emerged involving image norms, regression analyses revealed a significant two-way interaction for group norm x identification on recreational sportswomen's intentions to engage in sun protection in the next fortnight. Participants identifying strongly with their group had stronger intentions to engage in sun protection when exposed to a norm reflecting fellow recreational sportswomen engaging in sun-protective actions in comparison to those exposed to a non-supportive group. In addition, while prior intentions to engage in sun protection were not significantly related to sun-protection behavior, post-manipulation intentions after exposure to the sun-protective information that was provided were significantly related to follow-up behavior. Overall, the findings supported the importance of group-based social influences, rather than tanned media images, on sun-protective decisions among young recreational sportswomen and provided a targeted source for intervention strategies encouraging sun safety among this at-risk group for repeated sun exposure.  相似文献   
94.
Through the secretion of corticosterone, the hypothalamo-pituitary-adrenal (HPA) axis is thought to play an important role in the regulation of caloric intake and dietary fat preference. In an earlier study, we demonstrated a positive correlation between urinary corticosterone output and dietary fat preference. Furthermore, dietary fat preference was augmented following chronic but not acute hypercorticosteronemia produced by exogenous corticosterone administration. These observations led us to explore whether the HPA axis of rats exhibiting high preference for fat may have exaggerated sensitivity to corticotropinreleasing hormone (CRH). The results of these studies show a delayed and blunted but more prolonged corticosterone response to CRH in the fat-preferring rats compared with that of the carbohydrate-preferring rats.  相似文献   
95.
Objectives. To identify factors associated with academic help-seeking behavior among student pharmacists at a public university.Methods. Semi-structured focus group interviews were conducted to explore in depth perceptions of facilitators of and barriers to the help-seeking behavior and academic achievement of student pharmacists who had received a D or F grade in any year. A 4-part survey instrument was developed and administered to all student pharmacists and included sections for (1) attitudes and academic help-seeking behavior, (2) health status, (3) demographics, and (4) open comments. A structural equation modeling approach was used to assess relationships among domains of interest.Results. Three student focus groups noted that helpfulness of faculty members and school administrators were 2 prominent facilitators of help-seeking behavior and academic achievement. Diminished quality of life caused by stress and depression was the primary barrier to help-seeking and achievement. Three hundred four (68.6%) student pharmacists completed the survey instrument. Academic help-seeking behavior was influenced mostly by perceived academic competence and perceived faculty helpfulness. In contrast, ambivalence and perception of help-seeking as threatening were 2 factors that were negatively associated with academic help-seeking behavior.Conclusions. Academic help-seeking behavior was positively related to greater perceived academic competence and positive relationships among student pharmacists and faculty members.  相似文献   
96.
Solid lipid microparticles were investigated as a taste-masking approach for a lipophilic weak base in a suspension. The idea was that the drug concentration in the aqueous phase of a suspension might be reduced by its partitioning into the solid lipid particles. Loratadine, as a model drug, was used to prepare Precirol® ATO 5 microparticles by a Micromixer. The effects of three process variables: drug loading, PVA concentration and water/lipid ratio on the microparticle size, encapsulation efficiency, surface appearance, in-vitro release and drug partitioning in a suspension were studied. Loratadine release was slow in simulated saliva and very fast at the pH of stomach. In suspension of loratadine lipid microparticles, drug was released into the aqueous phase to the same concentration as in a drug suspension. Therefore, the usefulness of these microparticles for taste-masking in liquids is limited. However, they might be useful for taste-masking in solid dosage forms.  相似文献   
97.
The purpose of this research study was to describe and interpret the experience of nurses without any educational theory as they transition from the role of the clinical nurse expert to the novice nurse educator. A qualitative design with a phenomenology method was conducted of 8 clinical nurse experts who have transitioned into the role of the novice nurse educator within the past 2 years. Analysis of the data yielded 3 themes: (a) clinical nurse experts have expert knowledge to share and have a desire to educate the next generation; (b) the transition process elicits feelings of stress related to not having educational theory; (c) consistent mentoring contributes to an easier transition to the role. As a result of this study, nursing program administrators can assist the clinical nurse expert by providing additional support in areas of educational theory, examination writing, and analysis.  相似文献   
98.
The experience of bereavement by parental suicide is not well understood, as evidenced by the lack of empirically supported interventions for this underserved population. This article reviews quantitative and qualitative research on the psychopathological outcomes and thematic characteristics of childhood and adolescent suicide survivorship and moderating variables such as life stressors, stigma, the manner of communication about the suicide, and the surviving parent's functioning. The authors outline several approaches to intervention and address conceptual and methodological challenges within the field. With the ultimate goal of efficacious intervention, recommendations for future priorities and the use of unconventional research methods are offered.  相似文献   
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