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81.
Isolation of non-O1 Vibrio cholerae associated with enteric disease of herbivores in western Colorado. 总被引:3,自引:1,他引:3 下载免费PDF全文
Non-O1 Vibrio cholerae was isolated from a horse (Equus caballus), a lamb (genus Ovis), and two American buffalo (Bison bison) suffering from enteric disease in the western part of Colorado. In 1981, a foal died of apparent respiratory failure. Necropsy findings included heart failure and gastroenteritis. V. cholerae serovar 347 (Smith) was isolated from the colon of this animal. V. cholerae serovar 27 (Smith) was isolated in 1983 from the intestine of a feedlot lamb suffering from pneumonia and severe watery diarrhea. In 1984, an enteric disease occurred in a herd of American bison. The sick animals were depressed and separated from the herd, dying in about 3 days. Of approximately 100 adult bison, 7 died. Necropsy of one animal revealed that gross lesions were limited to the gastrointestinal tract. V. cholerae serovar 27 (Smith) was isolated from the abomasum, duodenum, and colon of this animal. A swab specimen from the intestine of another dead bison also yielded V. cholerae serovar 27 (Smith). 相似文献
82.
Peng?Dong Ling?Ling?Wong Sarah?Ng Marie?Loh Adrian?MondryEmail author 《BMC medical informatics and decision making》2004,4(1):21
Background
Critically Appraised Topics (CATs) are a useful tool that helps physicians to make clinical decisions as the healthcare moves towards the practice of Evidence-Based Medicine (EBM). The fast growing World Wide Web has provided a place for physicians to share their appraised topics online, but an increasing amount of time is needed to find a particular topic within such a rich repository.Methods
A web-based application, namely the CAT Crawler, was developed by Singapore's Bioinformatics Institute to allow physicians to adequately access available appraised topics on the Internet. A meta-search engine, as the core component of the application, finds relevant topics following keyword input. The primary objective of the work presented here is to evaluate the quantity and quality of search results obtained from the meta-search engine of the CAT Crawler by comparing them with those obtained from two individual CAT search engines. From the CAT libraries at these two sites, all possible keywords were extracted using a keyword extractor. Of those common to both libraries, ten were randomly chosen for evaluation. All ten were submitted to the two search engines individually, and through the meta-search engine of the CAT Crawler. Search results were evaluated for relevance both by medical amateurs and professionals, and the respective recall and precision were calculated.Results
While achieving an identical recall, the meta-search engine showed a precision of 77.26% (±14.45) compared to the individual search engines' 52.65% (±12.0) (p < 0.001).Conclusion
The results demonstrate the validity of the CAT Crawler meta-search engine approach. The improved precision due to inherent filters underlines the practical usefulness of this tool for clinicians.83.
84.
Tetracycline-regulated gene expression following direct gene transfer into mouse skeletal muscle 总被引:7,自引:0,他引:7
Jyotsna Dhawan Thomas A. Rando Sarah L. Elson Hermann Bujard Helen M. Blau 《Somatic Cell and Molecular Genetics》1995,21(4):233-240
For most experimental and therapeutic applications of gene transfer, regulation of the timing and level of gene expression is preferable to constitutive gene expression. Among the systems that have been developed for pharmacologically controlled gene expression in mammalian cells, the bacterial tetracycline (tet)-responsive system has the advantage that it is dependent on a drug (tet) that is both highly specific and non-toxic. The tet-responsive system has been previously used to modulate expression of cell cycle regulatory proteins in cultured cells, reporter genes in plants and transgenic mice and reporter genes directly injected into the heart. Here we show that orally or parenterally administered tet regulates expression of tet-responsive plasmids injected directly into mouse skeletal muscle. Reporter gene expression was suppressed by two orders of magnitude in the presence of tet, and that suppression was reversed when tet was withdrawn. These data show that skeletal muscle offers an accessible and well characterized target tissue for tet-controlled expression of genesin vivo, suggesting applications to developmental studies and gene therapy. 相似文献
85.
A prospective, randomized trial is described in which the usefulness of two tests in the control of anticoagulant therapy is compared. Fifty-two patients were controlled by the one-stage prothrombin time and 55 by the activated partial thromboplastin time. There was no significant difference in the incidence of bleeding between the two groups. When bleeding did occur, it was more often reflected by prolongation of the prothrombin time than of the activated partial thromboplastin time. The prothrombin time was found to have some practical advantages over the activated partial thromboplastin time. 相似文献
86.
Prerequisites for translating intervention research findings into practice are maintenance of results, generalization of effects and consistency of implementation. This report presents 12 months follow-up information on a randomized 2x2 factorial trial evaluating the incremental effects of adding (1) telephone follow-up or (2) a community resources utilization component to a basic touchscreen computer-assisted dietary goal-setting intervention for 320 type 2 diabetes patients. All conditions evidenced significant improvement from baseline to the 12 months follow-up across behavioral, biological and psychosocial measures. There were few consistent differences between conditions, but results were robust across interventionists and clinics. The telephone follow-up component appeared to enhance long-term results on some measures. When considered along with earlier results from a randomized trial that included a control condition without goal setting, it is concluded that this basic goal-setting intervention can be consistently implemented by a variety of interventionists and produce lasting improvements. 相似文献
87.
A N Schweitzer 《Infection and immunity》1993,61(4):1516-1522
Resistance to infection is often associated with proliferative T-cell responses corresponding to activation of the Th1 CD4+ T-cell subset, while the proliferative responses of chronically infected individuals are often limited. A mathematical model of the interaction between Th1 cells and a replicating pathogen has been used to demonstrate that antigen dose-dependent inhibition of Th1-cell proliferation may differentially predispose the host to resistance or chronic infection according to the level of exposure. Furthermore, the rapidity of pathogen turnover dramatically influences the qualitative relationship between exposure level and outcome, the temporal progression of infection, and the extent to which superimposed regulation of effector function (distinct from proliferation) will alter the predicted predisposition. 相似文献
88.
Risk and protective factors for suicidal behavior in abused African American women 总被引:12,自引:0,他引:12
Kaslow NJ Thompson MP Okun A Price A Young S Bender M Wyckoff S Twomey H Goldin J Parker R 《Journal of consulting and clinical psychology》2002,70(2):311-319
This study examined risk and protective factors that differentiate low-income, abused African American women (N = 200) who attempted suicide from those who had never made a suicide attempt. Results from multivariate analyses revealed that numerous and/or severe negative life events, a history of child maltreatment, high levels of psychological distress and depression, hopelessness about the future, and alcohol and drug problems were factors associated with attempter status. Protective factors associated with nonattempter status included hopefulness, self-efficacy, coping skills, social support, and effectiveness in obtaining material resources. Culturally competent intervention approaches for abused women should target increasing their protective factors and reducing their risk factors to decrease the likelihood that these women engage in suicidal behavior. 相似文献
89.
Carl F Weems Alan H Zakem Natalie M Costa Melinda F Cannon Sarah E Watts 《Journal of clinical child and adolescent psychology》2005,34(4):712-723
This study examined the physiological response (skin conductance and heart rate [HR]) of youth exposed to a mildly phobic stimulus (video of a large dog) and its relation to child- and parent-reported anxiety symptoms and cognitive bias in a community-recruited sample of youth (n = 49). The results of this study indicated that HR and skin-conductance response were associated with youth report but not parent report of their child's symptoms of anxiety disorders and that HR response was more strongly associated with anxiety symptoms than skin-conductance response. Physiological response was uniquely associated with youth-reported symptoms of anxiety rather than youth-reported depression. Finally, HR response interacted with cognitive bias in predicting childhood anxiety disorder symptoms in a manner consistent with theories of the etiology of anxiety disorders. 相似文献
90.
Michael Rossdale Terry Kemple Sarah Payne Michael Calnan Rosemary Greenwood 《The British journal of general practice》2007,57(535):152-154
Out-of-hours organisations are responsible for the care of patients 70% of the time, and their GPs act as gatekeepers to secondary care services. This observational study identifies the variations in GPs' out-of-hours referral rates to secondary care and factors that could explain these variations. One hundred and forty-nine GPs who worked in one UK general practice out-of-hours cooperative which served 19 practices with 167 000 registered patients. Data on patients who accessed the out-of-hours service over 3 years (2001-2004) were examined. Factors thought to be predictors of variation in referral rates were investigated using logistic regression analysis. There was a fivefold difference in referral rates between the lowest and highest referring quartiles of GPs (OR [odds ratio] = 4.56, CI [confidence interval] = 3.86 to 5.38). The sex (female) of the clinician, the time of the consultation (11 pm to 7 am), and the place of the consultation (home visit) accounted for some, but not all, of the increased referral rates. A doctor working out-of-hours disproportionately influences the fate of the patient, the number of hospital admissions, and extra costs to the health service. There is a need for follow-up studies to investigate the factors associated with referral behaviour, and how the variation relates to patient factors and the resources available. These findings could be used when planning the staffing of out-of-hours services to optimise appropriate care and minimise patients' exposure to unnecessary intrusive and expensive hospital care. 相似文献