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41.

Background  

Higher mortality rates among morbidly obese (BMI of ≥40 or ≥35 kg/m2 with weight-related comorbidities) subjects are mainly explained by comorbidities such as type 2 diabetes. As bariatric surgery ameliorates diabetes, obese diabetic subjects will receive great benefits from bariatric surgery. Screening for diabetes prior to surgical referral is therefore crucial.  相似文献   
42.

Background  

Pneumonia is among the main causes of illness and death in children <5 years of age. There is a need to better describe the epidemiology of viral community-acquired pneumonia (CAP) in developing countries.  相似文献   
43.
AIMS: Congestive heart failure (CHF) is characterized by elevated plasma norepinephrine (PNE) associated with a poor prognosis. Moxonidine selectively stimulates medullary imidazoline receptors which centrally inhibit sympathetic outflow and potently suppress levels of circulating PNE. This study was designed to evaluate the effects of central sympathetic inhibition on clinical and neurohumoral status in patients with CHF. METHODS AND RESULTS: This study evaluated 25 patients (age=69+/-7 years, 20 males) with symptomatic CHF (NYHA II-III), stabilized on standard therapy. The mean ejection fraction was 28+/-7% at baseline. Patients were titrated in a double-blind fashion to 11 weeks of oral therapy with placebo (n=9) or sustained-release (SR) moxonidine 0.9 mg bid (n=16). Clinical and neurohumoral status were evaluated at baseline, on chronic therapy at the target dose, and during cessation of therapy. All patients completed the trial and reached the target dose. Dry mouth, symptomatic hypotension, and asthenia were more frequent in the moxonidine SR-treated group. PNE was substantially reduced after 6 weeks at the maximum dose (0.9 mg bid) by 50% vs. placebo (P<0. 0005). A reduction in 24-h mean heart rate (P<0.01) was correlated to the reduction in PNE (r=0.70, P<0.05). A 36% increase in the standard deviation of normal-to-normal intervals (SDNN) was observed in the moxonidine SR group vs. a 2% decrease for placebo (P=0.06); for the root mean square of successive differences (rMSSD), there was a 21% increase for moxonidine SR vs. a 19% decrease for placebo (P<0.05). Abrupt cessation of chronic therapy resulted in substantial increases in PNE, blood pressure, and heart rate. CONCLUSIONS: Chronic therapy with a sustained-release formulation of moxonidine in patients with CHF was well tolerated, with substantial and sustained reductions in PNE. The tachyarrhythmias were attenuated, with evidence of improved autonomic tone. Due to the observed effects following moxonidine discontinuation, tapering of therapy is recommended.  相似文献   
44.

Background  

This study was conducted in order to elucidate metabolic differences between human rectal cancer biopsies and colorectal HT29, HCT116 and SW620 xenografts by using high-resolution magnetic angle spinning (MAS) magnetic resonance spectroscopy (MRS) and for determination of the most appropriate human rectal xenograft model for preclinical MR spectroscopy studies. A further aim was to investigate metabolic changes following irradiation of HT29 xenografts.  相似文献   
45.
The relationships between dose and antihypertensive effect of the first four available AT 1 -receptor blockers, i.e. losartan, valsartan, irbesartan and candesartan, were assessed based on data obtained from the FDA's evaluation reports of the respective New Drug Application files. All available randomized, double-blind, placebo-controlled, parallel-group studies in adult men and women with mild to moderate primary diastolic hypertension were included, provided that the reduction in trough (24 h post-dose) supine or sitting diastolic blood pressure (DBP) had been assessed using the intention-to-treat approach. All studies had an initial single-blind placebo run-in period followed by at least 4 weeks double-blind treatment. The selected studies were included in a meta-analysis of the dose-response relationship for each drug. The dose-response relationship was estimated by fitting the placebo-adjusted, weighted mean reductions in DBP for each dose of the drug to an E max model. The E max (maximal effect at an infinitely large dose) for the reduction in DBP, with corresponding 95% confidence intervals in brackets, were found to be 5.6 (3.6-7.5) mmHg for losartan, 5.8 (5.0-6.6) mmHg for valsartan, 6.9 (5.9-7.9) mmHg for irbesartan and 7.5 (6.1-8.9) mmHg for candesartan ( p = 0.014, candesartan vs valsartan). In conclusion, this investigation demonstrates that candesartan can reduce DBP significantly more than valsartan, and is supportive of previous head-to-head comparisons, which have proven candesartan to have a greater antihypertensive effect than losartan at recommended doses. Thus, differences in efficacy between different AT 1 -receptor blockers do exist, and should have implications for the choice of AT 1 -receptor blocker when treating patients with hypertension, considering the importance of good blood pressure control.  相似文献   
46.
INTRODUCTION: Studies using explanted tissue have shown that it is possible to keep adult human cells in organ culture with a preserved morphology for up to 1 month as spheres in a nonadhesive organ culture. AIMS: The current study was to determine whether human exocrine pancreatic cells also can be grown in this manner. METHODOLOGY: Small tissue samples from organ donors and tumor-free resection rim from patients with pancreatic carcinoma were obtained (n = 16 adults). From each patient, fragments of approximately 300 microm in diameter were cultured and investigated with light microscopy and scanning and transmission electron microscopy at the time of explantation and after 5, 10, 20, 30, and 40 days of culture. RESULTS: Incubation of cultured fragments with vital dyes revealed a viable epithelium. At the time of explantation all the tissue fragments had a rough appearance with an uneven, torn periphery. During the first week of culture the fragments became rounder, with a smooth surface covering the whole circumference. This spheroid morphology persisted for the rest of the 6-week culture period. The fragments were within 1 week covered by a highly differentiated, polarized epithelium with secretory apparatus, apical secretion granules, and microvilli, as well as specialized cell junctions, with the same appearance as acinoductal pancreatic cells of the original tissue. The core of the fragments consisted of connective tissue with vascular elements, fibroblasts, leukocytes, and a few ductal and acinar elements. Transmission electron microscopy of the spheroids revealed a continuous basal lamina underneath the epithelium. Immunostaining for cytokeratin 5, 6, 7, 8, 17, and 18 was strongly positive in the epithelium. CONCLUSION: These results show that normal exocrine pancreatic cells can be grown in vitro in a nonadhesive organ culture with their stroma.  相似文献   
47.
48.
BACKGROUND: Few longitudinal studies of dementia in Parkinson disease (PD) have been reported, and the proportion of patients with PD who eventually develop dementia is unknown. OBJECTIVE: To examine the 8-year prevalence, characteristics, and risk factors of dementia in patients with PD. METHODS: Patients were recruited from an epidemiological study of PD in the county of Rogaland, Norway, using explicit criteria for PD. Subjects with cognitive impairment at disease onset were excluded. A semistructured caregiver-based interview, cognitive rating scales, and neuropsychological tests were used to diagnose dementia according to criteria from the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition at baseline and 4 and 8 years later. A population-based sample of 3295 subjects in the municipality of Odense, Denmark, was used as a comparison group and examined at baseline and after 2 and 5 years. RESULTS: We included 224 patients with PD (116 women). At baseline, 51 patients (26%) had dementia. Fifty-five patients died, and 10 refused follow-up without their dementia status known. Forty-three and 28 new cases of dementia were identified at the 4- and 8-year evaluations, respectively. The 4-year prevalence of dementia in PD was nearly 3 times higher than in the non-PD group. The 8-year prevalence in PD was 78.2% (95% confidence interval [CI], 71.1-84.0). Risk factors for dementia were hallucinations before baseline (odds ratio [OR] = 3.1; 95% CI, 1.6-6.2) and akinetic-dominant or mixed tremor/akinetic PD (OR = 3.3; 95% CI, 1.2-8.5). CONCLUSIONS: More than three quarters of this representative PD cohort developed dementia during the 8-year study period. Early hallucinations and akinetic-dominant PD were associated with an increased risk of dementia.  相似文献   
49.
This paper reviews current concepts of root canal infection and the consequences for endodontic treatment strategies and practices. In particular, root canal disinfection by chemical and mechanical means is discussed, as are the possibilities and limitations of proposed methods to reduce the time necessary to obtain a disinfected canal.  相似文献   
50.
Pharmacokinetics and pharmacodynamics of levodopa were evaluated at a high-resolution level in a heterogeneous group of 10 patients with idiopathic Parkinson's disease during their normal daily activity. A physician and a nurse spent 10 hours with each patient from the first morning dose of levodopa during daily activities at home and at work. Plasma samples were obtained every 20 minutes for analysis of levodopa and 3-O-methyldopa by high-performance liquid chromatography. To assess clinical response, mobility was rated on every test occasion by patients and by investigators. Food and fluid intake and physical activity were also monitored. There was a large intra- and interindividual variability in the pharmacokinetics of levodopa regardless of the different drug combinations used. Mean plasma levodopa concentration ranged between 0.45 to 7.07 microg/mL and peak concentrations between 0.95 to 13.75 microg/mL. In 44 of 58 dosing events, an oral dose of levodopa was related to a peak in plasma concentration. Assessment of the clinical effects was more sensitive when given by patients than when given by the investigators. The fluctuations of the levodopa concentration in plasma had a clear effect on the clinical parameters assessed, even during early disease stages. Variation in levodopa concentration is the determining factor for motor fluctuations also in patients on clinically optimized combinations with dopamine agonists and enzyme inhibitors.  相似文献   
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