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41.
G H Rao V John T D Hill J L Vennerstrom J G White T J Holmes 《Thrombosis research》1986,44(4):527-538
The present study has evaluated the effect of some newly synthesized triphenylethylene (TPE) analogs on platelet arachidonic acid metabolism and function. All compounds tested inhibited arachidonic acid induced platelet aggregation and several were superior to aspirin in their relative potency. Introduction of a carboxyl function into the alpha-ring, which should enhance binding according to proposed structural models for cyclooxygenase inhibitors, was not found to be beneficial. Increased structural rigidity, which resulted from covalent linkage of two aromatic rings in this series, did not eliminate anti-aggregatory properties. 相似文献
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Does atopy have any predictive value for laboratory animal allergy? A comparison of different concepts of atopy 总被引:2,自引:0,他引:2
Atopy is widely used as a discriminant in selection for employment involving exposure to allergenic substances. The validity of this has been tested in a population with a known burden of what is largely considered to be an IgE mediated disease, laboratory animal allergy. The findings suggest that atopy is insufficiently sensitive and specific for this purpose and that this is probably true for other occupational allergic diseases. The relation between different concepts of atopy--namely, atopy defined by family history, by personal history, and by skin prick tests with common allergens--has also been examined. The subpopulations identified by these criteria differed appreciably. Different concepts of atopy should not be used synonymously as they often are at present. 相似文献
44.
OBJECTIVE: Screening colonoscopy has been shown to reduce mortality and cancer stage in hereditary nonpolyposis colorectal cancer (HNPCC) individuals. However, the benefit of screening in intermediate risk groups is unknown. The most recent national guidelines have recommended a reduction of screening frequency for the intermediate risk group. Therefore, this study aims to compare the results of colonoscopic screening in HNPCC and intermediate risk groups and assess the effect of the most recent screening protocol recommendations. METHOD: A total of 244 individuals; 108 from HNPCC families (28 mismatch repair gene carriers) and 136 from intermediate risk families were referred for regular colonoscopic screening by the Regional Genetics Service. Findings from 417 colonoscopies performed between 1992 and 2003 were evaluated. RESULTS: A total of three cancers, 39 adenomas and 41 hyperplastic polyps were found in the HNPCC group compared with one cancer, 22 adenomas and 19 hyperplasic polyps in the intermediate risk group. If the recent screening guidelines for the intermediate group were applied, then 89 (44%) fewer colonoscopies would have been performed. Although no cancers would have been missed, six adenomas (mean size = 5.7 mm, range 2-10 mm) with two graded as severely dysplasic and six hyperplastic polyps would not have been detected. CONCLUSION: The detection rate and distribution of adenomas were similar in both groups. If the new colonoscopic screening recommendations for the intermediate risk group had been applied, a small number of significant lesions would have been missed. 相似文献
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Context Residents in all disciplines serve as clinical teachers for medical students. Since the 1970s, there has been increasing evidence to demonstrate that residents wish to teach and that they respond positively to formal teacher training. Effective resident‐as‐teacher (RaT) programmes have resulted in improved resident teaching skills. Current evidence, however, is not clear about the specific features of an effective RaT programme. Objectives This study was performed in order to investigate the effectiveness of RaT programmes on resident teaching abilities and to identify the features that ensure success. Methods of assessment used to ascertain the effectiveness of RaT programmes are also explored. Methods The literature search covered the period between 1971 and 2008. Articles focusing on improving resident teaching skills were included. Each study was reviewed by two reviewers and data were collected using a standard abstraction summary sheet. Study outcomes were graded according to a modified Kirkpatrick's model of educational outcomes. Results Twenty‐nine studies met review inclusion criteria. Interventions included workshops, seminars, lectures and teaching retreats. Twenty‐six studies used a pre‐ and post‐intervention outcome comparison method. Subjective outcome measures included resident self‐evaluation of teaching skills or evaluation by medical students, peers and faculty members. Objective outcome measures included written tests, evaluation of teaching performance by independent raters and utilisation of objective structured teaching examinations. One study objectively measured learning outcomes at the level of medical students, utilising the results of an objective structured clinical examination. Overall resident satisfaction with RaT programmes was high. Participants reported positive changes in attitudes towards teaching. Participant knowledge of educational principles improved. Study methodologies allowed for significant risks of bias. Conclusions More rigorous study designs and the use of objective outcome measures are needed to ascertain the true effectiveness of RaT programmes. Future research should focus on determining the impact of RaT programmes on learning achievement at the level of medical students. 相似文献
47.
Public and professional debate over what, if any, action should be taken by state regulatory agencies regarding AIDS and the HIV status of dentists has increased in recent months. To determine if state boards had workable policies in place or were considering such policies, a telephone survey of all state boards was undertaken. All boards participated, although three provided only limited information. As of early 1992, only two boards required evidence of immunity to HVB for relicensure and none require evidence of seronegativity to HIV for relicensure. Twelve percent of the boards anticipate such requirements within two years. None have mandatory HIV testing, but 13 percent anticipate such requirements in the near future. The authors conclude that while few agencies have taken more than tentative steps toward rigorous HIV testing or restrictions, most are aware of much closer public scrutiny. More restrictions seem likely as these agencies attempt to balance public and professional rights and responsibilities. 相似文献
48.
Religious orientation, aging, and blood pressure reactivity to interpersonal and cognitive stressors
Kevin S. Masters Ph.D. Robert D. Hill Ph.D. John C. Kircher Ph.D. Tera L. Lensegrav Benson M.S. Jennifer A. Fallon M.S. 《Annals of behavioral medicine》2004,28(3):171-178
Background: Research on religion and health suggests general health benefits for those who are more religiously involved. Particular
aspects of religiosity that may influence this finding, however, have not been sufficiently investigated.Purpose: This study was designed to explore the relationship between religious orientation (intrinsic, extrinsic) and blood pressure
reactivity among older (over 60 years) and younger (18–24 years) adults exposed to two qualitatively different laboratory
stressors (cognitive, interpersonal).Methods:Participants were categorized as exhibiting either a predominately intrinsic or extrinsic religious orientation based on scores
on the Religious Orientation Scale. They were subsequently exposed (in counterbalanced order) to two laboratory stressors
that varied in terms of whether an interpersonal confrontation was involved. Measures of blood pressure were obtained at baseline
and during stressor presentation.Results: Analyses indicated that older extrinsically religious individuals demonstrated exaggerated reactivity compared to younger
participants and older intrinsically religious individuals. Older intrinsically religious participants did not differ from
younger persons. Similar results were found for analysis of baseline data. Extrinsic participants had greater reactivity during
the interpersonal confrontation condition than did intrinsic individuals.Conclusions: These findings suggest that religious orientation may be an important variable to study regarding cardiovascular reactivity
in, particularly, older adults.
This research was supported in part by National Institute on Aging Grant 1 R03 AG 18554-01. A previous version of this article
was presented in August 2002 as a Citation Paper at the 110th Annual Convention of the American Psychological Association,
Chicago.
We thank Timothy W. Smith, James A. Blumenthal, Carl E. Thoresen, and Edward M. Heath for their assistance throughout this
project. We also thank Llewellyn Jones and Jodi Hildabrandt for their efforts in collecting data. 相似文献
49.
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