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31.
BACKGROUND: A large portion of the elderly population of the United States fails to receive an annual influenza vaccination. Minorities may receive disproportionately fewer vaccinations. The objectives of this study were to (a) estimate the levels of influenza vaccination among noninstitutionalized, U.S. citizens, 65 years and older, (b) examine the immunization levels among minority racial and ethnic groups relative to various majority groupings, and (c) explore potential factors that may contribute to disparities in vaccination levels. METHODS: We analyzed data from the 1996 Medical Expenditure Panel Survey to compare influenza vaccination levels of different racial and ethnic groups among 2,309 persons aged 65 years and older. RESULTS: Whites had 68.0% (+/- SE 1.5%) current influenza vaccination, Hispanics 61.7% (+/- SE 4.1%), and blacks 47.3% (+/- SE 4.3%). Blacks differed significantly compared to whites. Adjustment for potential confounders such as increased health risk, age distribution, perceived health status, family size, poverty level, and the number of ambulatory visits to a health care provider failed to change this difference substantially. CONCLUSIONS: In 1996, among elderly noninstitutionalized, U.S. citizens, blacks relative to whites were less likely to have current influenza vaccinations. This relationship remained significant even after adjustments for potential confounding variables.  相似文献   
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BACKGROUND: The risk factors for the varying grades of erosive esophagitis (EE) severity could be better understood. For that reason. we evaluated the risk factors associated with EE in patients with gastroesophageal reflux disease. METHOD: We determined the presence and severity of EE (using the Los Angeles Classification) in patients with negative serology Helicobacterpylori who underwent esophagogastroduodenoscopy as part of screening in four prospective, multicenter, randomized, double-blind comparative trials of once-daily esomeprazole and omeprazole for the acute healing of erosive esophagitis. We also examined the baseline characteristics of enrolled patients, and identified risk factors for severe disease using a multivariable logistic regression model. RESULTS: Erosive esophagitis was documented in 6709 patients of a total of 10,294 patients who underwent endoscopy: of these. 34% had grade A. 39% had grade B. 20% had grade C. and 7% had grade D disease. The majority of patients were male (61%) and Caucasian (93%) with a mean age of 46 years. In the regression model, the following were significant independent risk factors for severe (grades C and D) versus mild erosive esophagitis (grades A and B): severe heartburn (adjusted odds ratio 1.79); prolonged heartburn > 5 years in duration (1.16); obesity (1.21); the presence of hiatus hernia (2.13); male gender (1.97); and Caucasian ethnicity (1.53). CONCLUSION: In this large sample of patients with predominantly H. pylori-negative gastroesophageal reflux disease, risk factors for severe erosive esophagitis were the duration and severity of heartburn, and obesity.  相似文献   
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The long time biokinetics of the radiolabeled somatostatin analogues 111In-DTPA-D-Phe(1)-octreotide was studied in nude mice transplanted with the human carcinoid tumor, GOT1. The results were compared with those from the patient with the original tumor. This patient has been diagnosed and later treated with 111In-DTPA-D-Phe(1)-octreotide. The animals received about 2 MBq 111In-DTPA-D-Phe(1)-octreotide (0.1 microg) by injection into a tail vein. The animals were killed 0.5 h-14 d after injection of the radiopharmaceutical. Tumor tissue and normal tissues were collected and weighed and measured for 111In activity. The 111In uptake in the tumor was higher than in all normal tissues except the kidneys. The tumor-to-normal-tissue activity concentration, TNC, increased with time for all normal tissues studied. These data were similar to those observed for the original tumor in the patient. The similar biokinetics for 111In-DTPA-D-Phe(1)-octreotide in the tumor-bearing mice and the patient makes this animal model suitable as a model for evaluation of therapy of somatostatin receptor (sstr) expressing tumors with radiolabeled somatostatin analogues. Furthermore, the increase with time of TNC both in mice and the patient indicates that long-lived radionuclides are preferred for therapy with radiolabeled somatostatin analogues.  相似文献   
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Objective To establish the antihypertensive properties of intravenous nimodipine used to treat eclamptic patients. To assess the effects of intravenous nimodipine on oxygen delivery and consumption.
Design A prospective observational study.
Setting The Maternity Centre Obstetric Intensive Care Unit, Groote Schuur Hospital.
Participants Four unselected patients presenting with proteinuric hypertension and seizures.
Methods Haemodynamic observations were obtained by a radial artery catheter and right heart catheterisation with a pulmonary artery flow directed thermodilution catheter. Observations were obtained prior to and after the administration of nimodipine.
Resuts A significant reduction in mean arterial pressure occurred in all patients after administration of nimodipine. This was due to a significant reduction in systemic vascular resistance. Neither oxygen delivery to the tissues nor peripheral oxygen consumption changed significantly during nimodipine infusion. No adverse effects related to the use of nimodipine were documented.
Conclusions Nimodipine is an effective vasodilator. There may be a role for nimodipine as a single agent for the management of eclampsia.  相似文献   
35.
The antiulcer activity of Maytenus aquifolium spray dried extract was studied in rats. Ulcers were induced by means of three experimental models: acidified-ethanol, indomethacin and acute stress. The extract was found to have significant antiulcer activity against all the models studied. These results show that preparation of the extract by means of the spray dried technique does not alter the biological activity of Maytenus aquifolium.  相似文献   
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Rationale Although 3,4-methylenedioxymethamphetamine (MDMA; Ecstasy) has been reported to cause fatal hyperthermia, few studies of the effects of MDMA on core body temperature in humans have been conducted demonstrating increased body temperature. In rats, MDMA causes hyperthermia at warm ambient temperatures but hypothermia at cold ones.Objectives In this study, the physiological and subjective effects of MDMA in humans were determined at cold (18°C) and warm (30°C) ambient temperatures in a temperature and humidity-controlled laboratory.Methods Ten healthy volunteers who were recreational users of MDMA were recruited. Four laboratory sessions were conducted in a 2×2 design [i.e., two sessions at 30°C and two at 18°C, two during MDMA (2 mg/kg, p.o.) and two during placebo, in double-blind fashion]. Core body temperature (ingested radiotelemetry pill), skin temperature (four weighted sites), heart rate, blood pressure, metabolic rate (indirect calorimetry), shivering (electromyogram levels), and sweat rate (capacitance hygrometry) were measured as well as subjective effects for several time periods following capsule ingestion.Results MDMA produced significant elevations in core body temperature and metabolic rate in both warm and cold conditions. MDMA also produced significant elevations in blood pressure and heart rate and significantly increased several ratings of subjective effects similar to those previously reported. There were no differences related to ambient temperature for any of the subjective effects, except that ratings of cold and warm were appropriate to the ambient temperature and were not influenced by MDMA.Conclusions Unlike findings in rats, MDMA increased core body temperature regardless of ambient temperature in humans. These increases appeared related to increases in metabolic rate, which were substantial. These findings warrant further investigations on the role of MDMA and other stimulants in altering metabolism and thermogenesis.  相似文献   
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This empirical study explores participants' perceptions of information and understanding of their children's and their own involvement in a longitudinal screening, the ABIS Study. ABIS (All Babies In Southeast Sweden) is a multicentre, longitudinal research screening for Type 1 diabetes and multifactorial diseases involving 17 005 children and their families. For this study, a random selection of mothers was made, using perinatal questionnaire serial numbers from the ABIS study. In total, 293 of these mothers completed an anonymous questionnaire (response rate 73.3%). Our findings from the questionnaire indicate a marked difference between the reported satisfaction with and understanding of the information provided on the one hand and the significant lack of knowledge of some of the aims and methods of the ABIS screening on the other, namely concerning high-risk identification of involved children, potential prevention and future questionnaires. Two questions evoked by our results are: (1) what information is required for participants in longitudinal studies involving children? and (2) how do we ensure and sustain understanding, and thus in a prolonging, informed consent in these studies? This study underlines the importance of an increased understanding of the ethical issues that longitudinal research on children raise and the need to discuss how information and informed consent strategies should be analysed and designed in longitudinal studies.  相似文献   
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