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51.
Joanne F. Berson Robert W. Doms Deborah Long 《Perspectives in Drug Discovery and Design》1996,5(1):169-180
Summary The glycosphingolipid galactosylceramide (GalCer) has been identified as an alternate receptor for the human immunodeficiency virus type 1 (HIV-1). Here we review a liposome flotation assay used to study the interaction of the HIV-1 envelope glycoprotein (env) with artificial membrane vesicles containing GalCer. The properties of binding, the nature of the env binding site for GalCer, and the implications of this interaction for HIV-1 infection are discussed. 相似文献
52.
A model for training the trainers of child care providers that employs Vygotsky's framework of the Zone of Proximal Development is described. This efficient training mechanism proposes mentoring relationships as a means to meet the developmental needs of experienced child care professionals and improve the quality of existing child care programs.The authors would like to thank Dr. Bille Thomas and the satellite resource center directors and staff members for their work on the project. 相似文献
53.
Dr. Joseph A. Paladino Pharm.D. Dr. Miguel A. Rainstein M.D. FACS Mrs. Deborah J. Serrianne R.N. Dr. John E. Przylucki M.D. FACS Dr. Lynda S. Welage Pharm.D. Dr. Mario L. Collura M.D. FACS Dr. Jerome J. Schentag Pharm.D. FCCP 《Pharmacotherapy》1994,14(6):734-739
This double-blind study compared ampicillin-sulbactam 3 g versus cefoxitin 2 g in 136 adult patients at risk for developing an infection after abdominal surgery. Separate randomization schedules were used for colorectal, upper gastrointestinal/biliary, and other abdominal procedures. Study antibiotics were administered within 30 minutes before incision and repeated 6 hours later. Patients having colorectal surgery received a third dose of antibiotic 6 hours after the second. Efficacy evaluations were made on 123 patients, 62 in the ampicillin-sulbactam group and 61 in the cefoxitin group. The overall postoperative infection rates were 12.9% for ampicillin-sulbactam and 9.8% for cefoxitin (p>0.05); one wound infection occurred in each group. Adverse events were experienced by 13.2% of the ampicillin-sulbactam and 19.1% of the cefoxitin recipients (p>0.05). Cost-minimization analysis revealed that ampicillin-sulbactam was a cost-effective alternative to cefoxitin for the prevention of infection after abdominal surgery. 相似文献
54.
M N Burnier I W McLean L E Zimmerman S H Rosenberg 《Investigative ophthalmology & visual science》1990,31(10):2037-2040
In 150 retinoblastomas the authors found a uniform thickness of the cuff of viable retinoblastoma cells that surrounds blood vessels. The mean thickness was 98.7 microns with a standard deviation of 11.9 microns. The cross-sectional area of the cuff was negatively correlated with the mitotic activity in the cuff and positively correlated with the diameter of the central vessel. The mitotic activity in the cuff of cells was inversely related to the distance from the central blood vessel. When the cuff was divided into three concentric rings, the inner ring contained a mean of 6.2 mitotic figures, the middle ring contained a mean of 2.9 mitotic figures, and the outer ring contained a mean of 0.6 mitotic figures. This pattern of growth is similar to that observed in other rapidly growing neoplasms in humans and experimental animals. In these tumors this pattern results from reduction in oxygen tension with increased distance from the central blood vessel. 相似文献
55.
Effect of dietary protein on the renin-angiotensin system in subtotally nephrectomized rats 总被引:1,自引:0,他引:1
Dietary protein restriction improves the course of renal disease in the remnant kidney model. Dietary protein restriction can also reduce plasma renin activity in several circumstances. We examined the interaction between dietary protein and the renin-angiotensin system in subtotally nephrectomized rats (1-2/3 nephrectomy). No difference was seen in tissue renin activity in rats ingesting a high (30%) versus a low (6%) protein diet. To determine the pathophysiological role of angiotensin II in subtotally nephrectomized rats, we examined the acute renal response to an intrarenal infusion of the angiotensin II antagonist Sar1 Gly8-angiotensin II (10 micrograms/kg/min). Only those subtotally nephrectomized animals ingesting a high protein diet exhibited a consistent improvement in glomerular permselectivity, as manifested by a 24% fall in the fractional clearance of albumin (basal 16.19 +/- 3.65 x 10(-4) vs. Sar1 Gly8-AII 12.26 +/- 3.21 x 10(-4); P less than 0.02) and a 19% fall in the fractional clearance of IgG (basal 3.75 +/- 0.67 x 10(-4) vs. Sar1 Gly8-AII 3.03 +/- 0.48 x 10(-4); P less than 0.02). No consistent change occurred in glomerular permselectivity in the rats on the low protein diet or rats infused with vehicle only. No change in mean arterial pressure or whole-kidney hemodynamics were seen with angiotensin II blockade. Decrements in SNGFR and glomerular capillary pressure occurred with angiotensin blockade in the animals ingesting the high protein diet, suggesting hemodynamic factors as a mechanism for the improvement in permselective defects.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
56.
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58.
Anne Rannard Deborah Buck David E J Jones Oliver F W James Ann Jacoby 《Clinical gastroenterology and hepatology》2004,2(2):164-174
BACKGROUND AND AIMS: Assessment of health-related quality of life (HRQOL) is not routinely reported in the literature on chronic liver disease (CLD). Few studies have examined quality of life (QOL) in patients with primary biliary cirrhosis (PBC) despite its significant functional impact. One of the reasons for the lack of HRQOL measurement in patients with PBC may be the absence of a well-recognized and widely used measure that clinicians can use in ordinary clinical practice. The aim of this study is to evaluate HRQOL measures used in patients with PBC and examine the suitability of the measures for these patients. METHODS: A literature search identified reports that focused on any aspect of QOL in patients with PBC. Key texts were identified containing generic, domain-specific, and condition-specific measures. The identified measures were systematically evaluated for appropriateness, acceptability, reliability, validity, precision, and responsiveness. RESULTS: Twenty measures were identified from 9 key texts. Six of the measures were previously validated generic measures; 10 were domain-specific measures previously used to measure fatigue, depression, and psychological distress in general and psychiatric populations; and 4 measures had been developed in patients with CLD. Reporting of reliability and validity generally was consistent for all measures used. However, reporting of the remaining criteria was variable, particularly in relation to responsiveness over time and acceptability of the measures to patients with PBC. CONCLUSIONS: A clearer and more rigorous approach is needed in reporting the properties of HRQOL measures used in patients with PBC to help clinicians decide which measures are most suitable for these patients. 相似文献
59.
Deborah Bray Preston Anthony R D'Augelli Cathy D Kassab Richard E Cain Frederick W Schulze Michael T Starks 《AIDS education and prevention》2004,16(4):291-303
Research investigating predictors of risky sexual behavior of rural MSM is sparse, even though the prevalence of HIV in rural areas has increased. This study explored two sets of predictors of 93 rural MSM's levels of risky sexual behavior: mental health variables and stigma emanating from men's family members, health care professionals, and people in the rural communities in which they live. Over 47% of the men were found to be at modified high to high risk. Logistic regression using a continuation logit model was used to test the relationship of the predictor variables and the four levels of risk. Findings indicate that self-esteem was predictive of the highest sexual risk behavior but not lower levels of risk. Stigma was predictive of modified high sexual risk when compared to low and no risk categories. No variables differentiated men at low risk from men at no risk. 相似文献
60.
Perioperative cardiac events in patients undergoing noncardiac surgery: a review of the magnitude of the problem, the pathophysiology of the events and methods to estimate and communicate risk 总被引:5,自引:0,他引:5
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P.J. Devereaux Lee Goldman Deborah J. Cook Ken Gilbert Kate Leslie Gordon H. Guyatt 《Canadian Medical Association journal》2005,173(6):627-634
THIS IS THE FIRST OF 2 ARTICLES EVALUATING cardiac events in patients undergoing noncardiac surgery. In this article, we review the magnitude of the problem, the pathophysiology of these events, approaches to risk assessment and communication of risk. The number of patients undergoing noncardiac surgery worldwide is growing, and annually 500 000 to 900 000 of these patients experience perioperative cardiac death, nonfatal myocardial infarction (MI) or nonfatal cardiac arrest. Although the evidence is limited, a substantial proportion of fatal perioperative MIs may not share the same pathophysiology as nonoperative MIs. A clearer understanding of the pathophysiology is needed to direct future research evaluating prophylactic, acute and long-term interventions. Researchers have developed tools to facilitate the estimation of perioperative cardiac risk. Studies suggest that the Lee index is the most accurate generic perioperative cardiac risk index. The limitations of the studies evaluating the ability of noninvasive cardiac tests to predict perioperative cardiac risk reveals considerable uncertainty as to the role of these popular tests. Similarly, there is uncertainty as to the predictive accuracy of the American College of Cardiology / American Heart Association algorithm for cardiac risk assessment. Patients are likely to benefit from improved estimation and communication of cardiac risk because the majority of noncardiac surgeries are elective and accurate risk estimation is important to allow informed patient and physician decision-making. 相似文献