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991.
The aim of the CASTEL, a population-based (n=3282) prospective study which began 14 years ago, was to identify those items which had a prognostic impact in the elderly, and to evaluate whether the typical cardiovascular risk factors, particularly arterial hypertension, play a role after the age of 65 years. Initial screening, final follow-up and annual detection of mortality were performed. Mantel-Hanszel approach and multivariate Cox model were used for statistics. Cardiovascular mortality was 23.3% in normotensive, 23.3% in borderline, and 25% in the sustained hypertensive subjects (insignificant difference). In women, the incidence of stroke and coronary artery disease weakly depended on pulse pressure. Historical stroke and myocardial infarction predicted cardiovascular mortality in women; diabetes, uricaemia and high heart rate in men. In the very old, the predictors were less numerous, and blood pressure was not a predictor whatsoever; pulse blood pressure and murmurs at the neck were especially predictive in women, historical heart failure, proteinuria and tachycardia in men, historical stroke and myocardial infarction, pulmonary disease, left ventricular hypertrophy, diabetes and uricaemia in both genders. The elderly have a different cardiovascular risk pattern compared to younger people. Hypertension is not a predictor of coronary and stroke mortality. Prognosis depends on pulse pressure rather than on the label 'hypertension'. Hypercholesterolaemia is not a risk factor. This could simply indicate that elderly persons are the survivors in a population where significant mortality has already made its mark, eliminating those with the worst risk pattern. The two genders have a different risk profile due to sex-specific susceptibility to risk factors.  相似文献   
992.
993.
AIMS: Comparing efficacy and safety of ibutilide vs. transoesophageal atrial pacing (ATP) for the termination of type I atrial flutter (AFL). METHODS AND RESULTS: Eighty-seven patients affected by AFL lasting between 2 h and 30 days were randomized in two groups: Group 1-i.v. ibutilide treatment, up to 2 mg, and Group 2-ATP, with "burst" and "ramp" pacing protocols. Sinus rhythm was restored in 36/45 (80%) patients in Group 1 vs. 18/42 (43%) in Group 2 (P<0.0005). In Group 1, mean AFL duration was 11.4 +/- 7.7 days in responders vs. 12.1 +/- 7.6 in non-responders (P=ns), while in Group 2 it was 2.7 +/- 1.4 vs. 14.2 +/- 5.4 days (responders vs. non-responders, respectively, P<0.0001); 30/36 (83%) responders in Group 1 had AFL >48 h vs. 10/18 (56%) responders in Group 2 (P<0.05). Non-sustained polymorphic ventricular tachycardia occurred in 2 patients in Group 1 vs. none in Group 2 (P=ns). It did not require any specific treatment except the interruption of ibutilide infusion. CONCLUSION: Both ibutilide and ATP proved to be safe and effective for recent onset type I AFL termination, but ibutilide was more effective when the arrhythmia had lasted longer than 48 h.  相似文献   
994.
Prevalence of hyperinsulinaemia in patients with high blood pressure.   总被引:4,自引:0,他引:4  
A total of 41 patients with hypertension were identified in a survey of 732 healthy factory workers. Twenty-three of these individuals were receiving antihypertensive medication, whereas 18 cases were newly discovered. Plasma glucose and insulin responses to oral glucose and fasting plasma triglyceride (TG), cholesterol, and high-density-lipoprotein (HDL) cholesterol concentrations of these 41 individuals were compared with those of 41 other factor workers, with normal blood pressure, matched with the hypertensive group in terms of gender, age, degree of obesity, job in the factory, and leisure-time activity. Patients with hypertension had significantly higher plasma glucose (P less than 0.05) and insulin (P less than 0.05) concentrations in response to oral glucose, as well as a higher plasma TG concentration (P less than 0.05). Similar findings were obtained when the treated and untreated hypertensive groups were analysed separately and compared with their respective control groups. However, there were no differences between the treated and untreated hypertensive groups. Ninety per cent of the normotensive group had a plasma insulin concentration of less than 500 pmol l-1 2 h after the glucose load. Using this value as the criterion for definition of hyperinsulinaemia, 41% of the patients with high blood pressure were hyperinsulinaemic. In addition to meeting this cut-off point, the patients with hypertension and hyperinsulinaemia were also glucose intolerant and dyslipidaemic. In conclusion, approximately 50% of an unselected group of patients with hypertension were hyperinsulinaemic. Insulin levels were comparable in treated and untreated patients with high blood pressure, and hyperinsulinaemic patients also tended to be glucose intolerant and dyslipidaemic.  相似文献   
995.
S ummary . Gγ, Aγ and β globin chain synthesis has been investigated in the peripheral blood and bone marrow from eight β-thalassaemia homozygotes. In five out of eight cases total γ chain synthesis was higher in the peripheral blood than in the bone marrow; in seven out of eight cases Aγ chain synthesis was markedly higher in the marrow than in the peripheral blood. These data suggest that ineffective erythropoiesis selects F-cells synthesizing the largest amounts of Gγ chains, while Aγ producing cells are preferentially destroyed in the marrow.  相似文献   
996.
The pathogenesis of mucoinfective lung disease in cystic fibrosis (CF) patients likely involves poor mucus clearance. A recent model of mucus clearance predicts that mucus flow depends on the relative mucin concentration of the mucus layer compared with that of the periciliary layer; however, mucin concentrations have been difficult to measure in CF secretions. Here, we have shown that the concentration of mucin in CF sputum is low when measured by immunologically based techniques, and mass spectrometric analyses of CF mucins revealed mucin cleavage at antibody recognition sites. Using physical size exclusion chromatography/differential refractometry (SEC/dRI) techniques, we determined that mucin concentrations in CF secretions were higher than those in normal secretions. Measurements of partial osmotic pressures revealed that the partial osmotic pressure of CF sputum and the retained mucus in excised CF lungs were substantially greater than the partial osmotic pressure of normal secretions. Our data reveal that mucin concentration cannot be accurately measured immunologically in proteolytically active CF secretions; mucins are hyperconcentrated in CF secretions; and CF secretion osmotic pressures predict mucus layer–dependent osmotic compression of the periciliary liquid layer in CF lungs. Consequently, mucin hypersecretion likely produces mucus stasis, which contributes to key infectious and inflammatory components of CF lung disease.  相似文献   
997.

Objective

The purpose of this study was to establish the frequency of burnout among doctors of chiropractic in the United States.

Methods

Using a nonprobability convenience sampling methodology, we e-mailed the Maslach Burnout Inventory–Human Services Survey and a sociodemographic questionnaire to a randomized sample of licensed doctors of chiropractic (n = 8000).

Results

The survey return rate was 16.06%. Twenty-one percent of the participants had high emotional exhaustion (EE), 8% had low personal accomplishment, and 8% had high depersonalization.

Discussion

Significant differences (P < .001) were found in the level of EE, depersonalization, and personal accomplishment as a function of sex, time dedicated to clinical care and administrative duties, source of reimbursement, the type of practice setting, the nature of practitioners' therapeutic focus, the location of chiropractic college, self-perception of burnout, the effect of suffering from a work-related injury, the varying chiropractic philosophical perspectives, and the public's opinion of chiropractic.

Conclusion

Although doctors of chiropractic in the United States who responded to the survey had a relatively low frequency of burnout, higher levels of EE remain workplace issues for this professional group.  相似文献   
998.

Background

Although most studies have found low rates of organic illness in patients with isolated psychiatric complaints, psychiatric patients are frequently brought to emergency departments (EDs) for medical clearance.

Study Objectives

To assess the utility of ED medical clearance before transfer of pediatric patients on psychiatric holds to inpatient psychiatric facilities, and to evaluate charges associated with ED medical clearance.

Methods

Retrospective study of pediatric psychiatric patients in one urban pediatric ED with 22,000 annual patient visits over an 18-month period. Patients were included if transported to the ED for medical clearance after being placed on an involuntary psychiatric hold in the prehospital setting. Main outcome measures were charges for screening laboratory tests and secondary ambulance transfers and wages for sitters resulting from ED visits for medical screening examinations of patients on psychiatric holds. We also determined what percentage of patients truly warranted a medical screen and the percentage of psychiatric holds overturned, avoiding transfer to a psychiatric hospital.

Results

There were 789 patients included; 72 (9.1%) were determined to require medical screening. Total charges for laboratory assessments and secondary ambulance transfers and wages for sitters were $1,241,295, or US$17,240 per patient requiring a medical screen. Only 35 (4.4%) holds were overturned in the ED.

Conclusion

Few patients brought to the ED on an involuntary hold required a medical screen. Use of basic criteria in the prehospital setting to determine who required a medical screen (altered mental status, ingestion, hanging, traumatic injury, unrelated medical complaint, rape) could have led to significant savings.  相似文献   
999.
1000.

Background

Liver transplantation (LT) with grafts from hepatitis B core antibody (HBcAb)-positive donors has been the object of recent studies, suggesting different outcomes depending on the etiology of viral cirrhosis in the recipient.

Methods

From November 2002 to December 2009, we transplanted 124 livers from hepatitis B surface antigen (HBsAg)-negative HBcAb-positive deceased heart-beating donors to adult recipients with viral cirrhosis, classified as: HBsAg positive (group 1; n = 63); hepatitis C virus (HCV) RNA positive (group 2; n = 52); and simultaneously HBsAg and HCV-RNA positive (group 3; n = 9). Immunosuppression included a calcineurin inhibitor, mycophenolate, and steroids (tapered to suspension in 6 months). In all groups, anti-HBV prophylaxis was performed with anti-HBs immunoglobulins and nucleos(t)idic analogues.

Results

The groups were similar regarding donor, recipient, donor-recipient match, transplant procedure, variables, and treatment of acute rejection, except for younger recipient age in group 1 (P = .009), lower recipient body mass index in group 3 (P = .03), and longer cold ischemia time in group 2 (P = .003). Median follow-up for surviving grafts was 63 (range, 16-102) months. No case of recurrent or de novo hepatitis B occurred. The prevalence of histologically proven recurrent HCV hepatitis was similar in groups 2 and 3 (65% vs 78%). Graft survival at 5 years was 86% in group 1, 35% in group 2, and 31% in group 3 (P < .0001 for group 1 vs 2; P < .01 for group 1 vs 3). On multivariate analysis, independent predictors of worse graft survival were HCV infection in the recipient (HR 8.08, 95% CI 3.36-17.97; P < .0001) and MELD at LT ≥25 (HR 3.72, 95% CI 1.12-12.37; P = .032).

Conclusions

The presence of HCV infection in the recipient is the factor which most negatively influenced the outcome of LT using grafts from HBcAb-positive donors. Allocation of such grafts should consider the type of viral cirrhosis among LT candidates.  相似文献   
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