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991.
alpha 2-Adrenoceptors on blood platelets have been widely used as a model for alpha-adrenoceptors in less accessible tissues. The effect of oestrogen (200 micrograms/day intramuscularly) on alpha 2-adrenoceptor number and function was studied in immature female rabbits. alpha 2-adrenoceptor number was measured in whole platelets, and membrane preparations of forebrain, hindbrain, spleen and kidney by radioligand binding. alpha 2-Adrenoceptor function was examined by measuring platelet aggregation in vitro and circulatory responses to selective alpha 2-adrenoceptor agonists in vivo. Oestrogen treatment resulted in a significant decrease in platelet alpha 2-adrenoceptor number and function. However, no changes were observed either in receptor number in other tissues or in responses to alpha 2-agonists in vivo. The results suggest that oestrogen modulation of rabbit platelet alpha 2-adrenoreceptor number and function may be different from that of brain, kidney and spleen. Caution should be exercised in extrapolating results from platelets to alpha-adrenoceptors at other sites.  相似文献   
992.
This SAEM position paper clarifies the role of emergency medicine in health care delivery. It builds upon the working definition of emergency medicine developed by the American College of Emergency Physicians in 1994 by describing the health care role of emergency physicians (EPs). EPs are first-contact providers who care for all patients regardless of age, gender, time of presentation, or ability to pay. They remain the only continuously accessible specialty for patients seeking help and solace in the health care system. They are an essential link in the health care continuum between primary care physicians, specialists, the out-of-hospital system, the patient, inpatient services, and communication services. The EP's role is in organizing and monitoring the emergency care delivery system. Part of this role is to better align the health care provider training and ability with the specific medical needs of a patient. The emergency health care system remains the essential medical safety net for all individuals needing care in this country.  相似文献   
993.
Highlights of an electronic healthcare record include clinical reminders, progress note templates, and a clinical reference system.  相似文献   
994.
995.
Chronic graft-versus host disease (GVHD) is a chronic and disabling complication after hematopoietic cell transplantation (HCT). It is important to understand the association of socioeconomic status (SES) with health outcomes in patients with chronic GVHD because of the impaired physical health and dependence on intensive and prolonged health care utilization needs in these patients. We evaluated the association of SES with survival and quality of life (QOL) in a cohort of 421 patients with chronic GVHD enrolled on the Chronic GVHD Consortium Improving Outcomes Assessment study. Income, education, marital status, and work status were analyzed to determine the associations with patient-reported outcomes at the time of enrollment, nonrelapse mortality (NRM), and overall mortality. Higher income (P?=?.004), ability to work (P?<?.001), and having a partner (P?=?.021) were associated with better mean Lee chronic GVHD symptom scores. Higher income (P?=?.048), educational level (P?=?.044), and ability to work (P?<?.001) also were significantly associated with better QOL and improved activity. In multivariable models, higher income and ability to return to work were both significantly associated with better chronic GVHD Lee symptom scores, but income was not associated with activity level, QOL, or physical/mental functioning. The inability to return to work (hazard ratio, 1.82; P?=?.019) was associated with worse overall mortality, whereas none of the SES indicators were associated with NRM. Income, race, and education did not have statistically significant associations with survival. In summary, we did not observe an association between SES variables and survival or NRM in patients with chronic GVHD, although we found some association with patient-reported outcomes, such as symptom burden. Higher income status was associated with less severe chronic GVHD symptoms. More research is needed to understand the psychosocial, biological, and environmental factors that mediate this association of SES with major HCT outcomes.  相似文献   
996.
997.
The effects of a 48-hour 0.5 mg/kg/hr infusion of the thromboxane synthase inhibitor pirmagrel were studied in 10 renal allograft recipients with cyclosporine nephrotoxicity. Plasma concentrations reached a mean steady-state plasma level of 1798 +/- 481 ng/ml. Biphasic, rapid elimination of pirmagrel was observed with a distribution half-life of 6.7 minutes and a terminal half-life of 73 minutes. Plasma clearance and the volume of distribution of the drug were 300 +/- 87 ml/hr/kg and 497 +/- 232 ml/kg, respectively. The pharmacodynamic effects of pirmagrel were marked by a mean 96% suppression of serum thromboxane B2 (TXB2), which coincided with a suppression of urinary excretion of TXB2, 2,3-dinor-TXB2, and 11-dehydro-TXB2 of 85% +/- 8%, 91% +/- 5%, and 89% +/- 9%, respectively. Urinary excretion of all thromboxane metabolites measured at the end of 1 week after termination of infusion was returned to the baseline. In conclusion, pirmagrel caused effective and sustained suppression of all thromboxane derived metabolites in plasma and urine during continuous infusion in kidney transplant patients receiving cyclosporine.  相似文献   
998.
A survey examining nurses' knowledge of pain control.   总被引:1,自引:0,他引:1  
Three hundred and eighteen (318) nursing staff members at an acute care teaching hospital in Montreal, Canada, were surveyed to identify their knowledge of pain assessment and management. Two pain instruments were combined and adapted for use. The final instrument consisted primarily of true/false responses and took about 10 min to complete. The mean score was 63.9%. Overall results indicated that nurses lacked knowledge and understanding of opioid addiction, equivalent dosing, properties of opioids, and differences in acute and chronic pain. No statistically significant differences were found in the scores by level of educational preparation or by years of experience. Presentation of the results unit by unit demonstrated that the instrument is suitable as an educational tool as well as an effective strategy to introduce nursing staff to nursing research.  相似文献   
999.
1000.
OBJECTIVE: To examine the influence of caffeine on the frequency and perception of hypoglycemia in "free-living" patients with type 1 diabetes. RESEARCH DESIGN AND METHODS: A total of 34 patients with type 1 diabetes were recruited for a prospective randomized placebo-controlled double-blind study. After a lead-in phase and while adhering to a low-caffeine diet, subjects were randomized to capsules containing either 200 mg caffeine or matched placebo with crossover at 3 months. Hypoglycemic episodes were monitored throughout with capillary blood glucose readings and a symptom questionnaire. During the study, measurements of blood pressure, middle cerebral artery blood velocity (a surrogate measure of cerebral blood flow), cognitive function (via a four-choice reaction time test), HbAlc levels, and lipid profiles were taken at the beginning and end of each phase. RESULTS: Throughout the study, no changes were evident regarding glycemic control or lipid profile. The number of symptomatic episodes was greater with caffeine (1.3 vs. 0.9 episodes/week; P < 0.03) and was associated with more intense warning symptoms (29 vs. 26 total symptom score; P < 0.05). For women, caffeine ingestion caused a modest pressor response (115 vs. 110 mmHg; P < 0.01). Four-choice reaction time improved slightly with caffeine supplementation (P < 0.05). CONCLUSIONS: Ingestion of modest amounts of caffeine enhances the intensity of hypoglycemia warning symptoms in patients with type 1 diabetes without altering the prevailing standard of glycemic control or increasing the incidence of severe hypoglycemic episodes.  相似文献   
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