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1.
PURPOSE: Many preceptors fill out students' clerkship-performance forms with all items marked with the maximum value. Because items are usually designed to measure somewhat specific behaviors, the authors questioned the validity of straight-line five (SL5) responses, and conducted an empirical validity study to investigate the measurement properties of these SL5 forms. METHOD: In 1999-00 the authors undertook a correlation study and a generalizability study to assess the measurement characteristics of the SL5 forms. For the correlation study, they calculated mean scores for each of 168 students across forms, excluding the SL5 forms, then correlated this mean with the proportion of straight-line forms the student received. They conducted a generalizability analysis with and without the straight-line forms to determine the impact on score reliability. RESULTS: The proportion of SL5 forms was significantly correlated (r =.48, p <.0001) with the mean student score. Inclusion of the SL5 forms did not negatively affect the reliability of the mean score. CONCLUSION: The SL5 forms appear to be valid ratings of students' performances. An informal comparison of the comments on SL5 forms and those not displaying this format supported this conclusion.  相似文献   
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This investigation compared progressive muscle relaxation plus cognitive distraction (PMR/CD), hypothesized to better improve sleep onset, versus sleep restriction and stimulus control (SR/SC), hypothesized to better improve sleep maintenance, versus a flurazepam (Dalmane) positive contrast condition (MED) and a sleep hygiene education minimal treatment control condition (SHE). Participants with chronic insomnia (N = 53), completed 2 baseline weeks of sleep diaries, and were randomly assigned to a treatment group for 2 more weeks. In the second phase, PMR/CD participants were assigned to 2 weeks of PMR/CD + SR/SC + SHE while SHE participants continued SHE. Results indicated that PMR/CD had greater effect upon sleep onset than SR/SC and SHE, SR/SC had greater effect on sleep maintenance than PMR/CD, and MED was better than the other treatments. In the second phase, the treatment package produced modest additional improvements and SHE performed superior to expectations.  相似文献   
4.
Archives of Sexual Behavior - Male couples in open relationships tend to have as equally fulfilling relationships as monogamous male couples; however, less is known about communication differences...  相似文献   
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Taking a patient-oriented approach to developing lifestyle interventions includes incorporating the patient into the program’s design, delivery, and evaluation. This commentary assumes that a patient-oriented approach has not yet been implemented and tested in exercise-based interventions designed for pregnant women. We outline and define a patient-oriented approach to conduct exercise-based research and review previous physical activity interventions designed for pregnant women to determine whether a patient-oriented approach was applied. In addition, pregnant women living with obesity may have unique barriers to engaging in prenatal exercise interventions that have not been previously addressed, such as having experienced weight stigma before pregnancy in healthcare and fitness settings. We propose suggestions for future trials to effectively take a patient-oriented approach when designing and implementing prenatal exercise interventions to address patient-informed barriers and incorporate suggested facilitators for physical activity. Given that prenatal activity levels are low and pregnant women may have unique barriers to engaging in exercise interventions, a patient-oriented approach may be an effective strategy to improve inclusivity and equity and, as a result, increase uptake and adherence to the intervention.  相似文献   
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Vegetables,fruit, and cancer. II. Mechanisms   总被引:13,自引:0,他引:13  
The epidemiologic literature on the relationship between vegetable and fruit consumption and human cancer at a variety of sites was reviewed systematically in Part I.1 It was concluded that consumption of higher levels of vegetables and fruit is associated consistently, although not universally, with a reduced risk of cancer at most sites, and particularly with epithelial cancers of the alimentary and respiratory tracts. Possible mechanisms by which vegetable and fruit intake might alter risk of cancer are addressed here. A large number of potentially anticarcinogenic agents are found in these food sources, including carotenoids, vitamins C and E, selenium, dietary fiber, dithiolthiones, glucosinolates and indoles, isothiocyanates, flavonoids, phenols, protease inhibitors, plant sterols, allium compounds, and limonene. These agents have both complementary and overlapping mechanisms of action, including the induction of detoxification enzymes, inhibition of nitrosamine formation, provision of substrate for formation of antineoplastic agents, dilution and binding of carcinogens in the digestive tract, alteration of hormone metabolism, antioxidant effects, and others. It appears extremely unlikely that any one substance is responsible for all the associations seen. Possible adverse effects of vegetable and fruit consumption are also examined. One way to consider the relationships reviewed here is to hypothesize that humans are adapted to a high intake of plant foods that supply substances crucial to the maintenance of the organism, but only some of which are currently called essential nutrients. Cancer may be the result of reducing the level of intake of foods that are metabolically necessary—it may be a disease of maladaptation.Authors are with the Division of Epidemiology, School of Public Health, University of Minnesota, 1-210 Moos Tower, 515 Delaware Street SE, Minneapolis, MN 55455, USA. Address correspondence to Dr Potter. This work was supported by NIH Grants CA 50305, CA 46618, and CA 09607.  相似文献   
7.
A discrepancy between clinical findings and a markedly elevated testosterone (T) level stimulated search to explain this inconsistency. The cause of the falsely elevated T level was determined to be heterophile antibodies from a polyclonal gammopathy in a subject with acute myelogenous leukemia.  相似文献   
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Introduction. The number of patients undergoing intravenous (IV) cannulation by paramedics has increased dramatically over recent years in the UK. Treatment protocols for cannulation in the field are loosely defined. Variation in practice may lead to patients' receiving differential treatment according to customary practice, rather than according to their clinical conditions. Objectives. To explore variations in practice and assess level of appropriatenesss of IV cannulation by London Ambulance Service (LAS) paramedics; to revise treatment protocols and work toward clinical guidelines, if indicated by study findings. Methods. Skill usage data were analyzed for all LAS paramedics for 1995–96. All patients who were IV-cannulated and transported to three hospitals by LAS during March 1996 were identified. A panel of accident and emergency (A&E) and prehospital specialists judged each case for appropriateness. Results. Variation during the year was wide, with a range of 1 to 221 (mean 47) patients cannulated per paramedic, although the majority showed some consistency in frequency of skill usage. A sample of 183 cases was reviewed. The majority judged 149 (81.4%) to be appropriate, although there was considerable disagreement between reviewers (κ = 0.43, p < 0.001). Data suggested that those paramedics who cannulate more frequently cannulated less appropriately during the study period (lowest 30%: 73.9% appropriate; highest 30%: 45.8% appropriate, p = 0.05). Conclusion. Despite wide variation between paramedics, the panel judged overall appropriateness of cannulation to be high. The audit advisory group judged that new clinical guidelines might not achieve an improvement in practice and were not supported by study findings. It was recommended that variations be addressed through individual practice review.  相似文献   
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Background and objectives

Blood pressure monitoring offers a limited understanding of the hemodynamic consequences of spinal anesthesia for cesarean delivery. The purpose of this study was to assess, with the aid of a non-invasive cardiac output monitor based on bioreactance, the hemodynamic changes during elective cesarean delivery under spinal anesthesia in which intermittent boluses of phenylephrine were used to prevent and treat hypotension.

Methods

This observational study was conducted with the Research Ethics Board approval, and all participants provided written informed consent. Healthy patients undergoing elective cesarean delivery under spinal anesthesia were enrolled. Intermittent boluses of phenylephrine were administered in an attempt to maintain systolic blood pressure at baseline levels, and patients were assessed with a non-invasive cardiac output monitor based on bioreactance. Hemodynamic data was collected continuously at baseline, and during the postspinal and postdelivery periods. Data was analyzed using a mixed model ANOVA, and a p < 0.05 was considered significant.

Results

Systolic blood pressure was maintained within 79.2 ± 14.2 and 105.8 ± 10.0 percent of baseline during the postspinal period, and 78.4 ± 11.3 and 100.9 ± 10.7 percent of baseline in the postdelivery period (mean ± SD) There were significant fluctuations in systolic blood pressure, heart rate, and cardiac output during the postspinal period, and significant fluctuations in systolic blood pressure and cardiac output in the postdelivery period.

Conclusions

A new non-invasive monitor based on bioreactance reveals significant hemodynamic fluctuations during cesarean delivery under spinal anesthesia, despite attempts to maintain blood pressure at baseline levels with intermittent boluses of phenylephrine.  相似文献   
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