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91.
Jennifer S Myers Lisa M Bellini Jon B Morris Debra Graham Joel Katz John R Potts Charles Weiner Kevin G Volpp 《Academic medicine》2006,81(12):1052-1058
PURPOSE: To assess internal medicine and general surgery residents' attitudes about the effects of the Accreditation Council for Graduate Medical Education duty hours regulations on medical errors, quality of patient care, and residency experiences. METHOD: In 2005, the authors surveyed 200 residents who trained both before and after duty hours reform at six residency programs (three internal medicine, three general surgery) at five academic medical centers in the United States. Residents' attitudes about the effects of the duty hours regulations on the quality of patient care, residency education, and quality of life were measured using a survey instrument containing 19 Likert scale questions on a scale of 1 to 5. Survey responses were compared using the Student's t-test. RESULTS: The response rate was 80% (159 residents). Residents reported that whereas fatigue-related errors decreased slightly, errors related to reduced continuity of care significantly increased. Additionally, duty hours regulations somewhat decreased opportunities for formal education, bedside learning, and procedures, but there was no consensus that graduates would be less well trained after duty hours reform. Residents, particularly surgical trainees, reported improvements in quality of life and reduced burnout. CONCLUSIONS: Residents in medicine and surgery had similar opinions about the effects of duty hours reform, including improved quality of life. However, resident opinions suggest that reduced fatigue-related errors have been offset by errors related to decreased continuity of care and that the quality of the educational experience may have declined. Quantifying the degree to which regulating duty hours affected errors related to discontinuity of care should be a focus of future research. 相似文献
92.
93.
Endocrine aspects of sarcoidosis 总被引:1,自引:0,他引:1
94.
During the last few years studies in rats and mice have demonstrated IgE-binding factors, some of which have IgE-selective regulatory activities. This prompted us to develop a rapid, sensitive screening assay for measuring IgE-binding factors in humans. The principle of the assay is to measure the degree of inhibition of binding between anti-human IgE antibodies and human IgE. Thus, 200 pg IgE plus testing samples were added to each well precoated with anti-human IgE antiserum. After an overnight incubation, the wells were washed and radiolabeled anti-IgE antibodies were added to the wells. Under the optimum conditions, the assay can detect 10(-11)M anti-human IgE antibodies. With this assay, we have been able to detect IgE-binding factors in the supernatants of 2 human B cell lines which bear Fc receptors for IgE (FcR epsilon) on their surface membranes (e.g., WIL-2 and RPMI 8866), but not in the supernatants of DAUDI cells (a human cell line without FcR epsilon). Furthermore, the IgE-binding factors of WIL-2 cells were specifically adsorbed to, and eluted from, IgE-coupled Sepharose, but not BSA-Sepharose. These findings prove that the inhibition factors are indeed human IgE-binding factors, and that the assay described herein is a specific and sensitive screening assay for detecting human IgE-binding factors. 相似文献
95.
Neuronal growth factors and development of respiratory control 总被引:6,自引:0,他引:6
Katz DM 《Respiratory physiology & neurobiology》2003,135(2-3):155-165
Neurotrophic molecules, released by neurons and neural target tissues, play a pivotal role in regulating neuronal development and plasticity. This article reviews recent work demonstrating the pivotal role of two such molecules, brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF), in the growth and maturation of respiratory neurons and the expression of normal ventilatory behavior. Although BDNF and GDNF are structurally dissimilar and signal through wholly distinct receptors, they are both required for development of peripheral chemoafferent neurons that provide hypoxic drive to the brainstem respiratory network. Studies of genetically engineered mice carrying targeted deletions in the genes encoding BDNF and GDNF, as well as genetic linkage analysis in humans, indicate that these trophic molecules may be candidate genes for human developmental disorders of breathing. 相似文献
96.
A I Katz 《The American journal of physiology》1982,242(3):F207-F219
Na-K-ATPase, the enzymatic equivalent of the sodium:potassium pump, is found in large amounts in the kidney, and this organ has figured prominently both as a source for the purification of the enzyme and as a target for the study of its properties. Located on the basolateral aspect of tubule cells, renal Na-K-ATPase plays a key role in the active translocation of Na and K across this membrane as well as in the "secondary active" transport of a number of other solutes. The activity of renal Na-K-ATPase varies in parallel with sustained changes in Na or K transport, indicating the participation of this enzyme in the chronic adaptation of the kidney to altered Na reabsorption or K secretory load. Because of its slow turnover, however, the role of Na-K-ATPase in the modulation of acute changes in cation transport is unclear. Several hormones and vanadate influence renal Na-K-ATPase activity, and their importance as potential physiologic regulators of this enzyme is examined. Most of the information on the renal enzyme has been obtained from studies using homogenates or subcellular fractions thereof, but more recently the development of tubule microdissection and microanalytic methods has made possible the study of Na-K-ATPase in single nephron segments. This approach has opened new possibilities for evaluating the role of this enzyme in kidney function by facilitating correlation of enzyme activity with transport events in the same structure and by enabling us to focus the study of Na-K-ATPase on discrete anatomic subdivisions of the functionally heterogeneous nephron. 相似文献
97.
R B Knight A Atkins C J Eagle N Evans J W Finkelstein D Fukushima J Katz H Weiner 《Psychosomatic medicine》1979,41(1):40-49
This study was designed to investigate the relationship between the effectiveness of coping mechanisms and physiological indicators of distress in children faced with the experience of hospitalization and surgery. Twenty-five children between the ages of 7 and 11 were studied in the out-patient department, 2 weeks before surgery, and again during their hospital stay. Effectiveness of defenses and defense style was measured by a clinical interview and by the Rorschach test. Cortisol production rates were measured by the analysis of 24-hour urine collections at home and again in the hospital. Ward adjustment was also rated by a ward questionnaire. The results indicated no relationship between defense effectiveness and cortisol production rates in the out-patient department and an inverse relationship between cortisol production and defense effectiveness under the stress of hospitalization. Defense style was found to correlate with coping under stress. Four different groups of children emerged, suggesting four different types of reaction to the hospital experience. 相似文献
98.
D B Clark W N Drohan S I Miekka A J Katz 《Annals of clinical and laboratory science》1989,19(3):196-207
Advances in biotechnology are permitting significant changes in traditional plasma fractionation schemes. Increases in product purity, safety, and recovery are possible, and new products are being developed. Applications of technology to the purification of factor IX, factor X, protein C, antithrombin III, thrombin, and fibrin glue are described. 相似文献
99.
100.
Carcinoid tumor of the pancreas is extremely rare. This article describes the case of a 22-year-old woman who manifested a typical carcinoid syndrome; a definitive diagnosis of a metastatic carcinoid tumor was made from needle aspiration of a supraclavicular lymph node using morphologic, immunocytochemical, and ultrastructural criteria. The carcinoid tumor was subsequently shown to be of pancreatic origin. 相似文献