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91.
CONTEXT AND OBJECTIVE: Obesity is associated with several metabolic abnormalities. Recent studies suggest that obesity also affects brain function and is a risk factor for some degenerative brain diseases. The objective of this study was to examine the effects of weight gain and weight loss on brain gray and white matter structure. We hypothesized that possible differences seen in the brains of obese subjects would disappear or diminish after an intensive dieting period. METHODS: In part I of the study, we scanned with magnetic resonance imaging 16 lean (mean body mass index, 22 kg/m(2)) and 30 obese (mean body mass index, 33 kg/m(2)) healthy subjects. In part II, 16 obese subjects continued with a very low-calorie diet for 6 wk, after which they were scanned again. Regional brain white and gray matter volumes were calculated using voxel-based morphometry. RESULTS: White matter volumes were greater in obese subjects, compared with lean subjects in several basal brain regions, and obese individuals showed a positive correlation between white matter volume in basal brain structures and waist to hip ratio. The detected white matter expansion was partially reversed by dieting. Regional gray matter volumes did not differ significantly in obese and lean subjects, and dieting did not affect gray matter. CONCLUSIONS: The precise mechanism for the discovered white matter changes remains unclear, but the present study demonstrates that obesity and dieting are associated with opposite changes in brain structure. It is not excluded that white matter expansion in obesity has a role in the neuropathogenesis of degenerative brain diseases.  相似文献   
92.
Valproic acid (VPA), an inhibitor of histone deacetylases, inhibits the growth of leukemia cells and induces their differentiation in vitro. In the present study, VPA in combination with two differentiating agents, 13-cis retinoic acid and 1,25-dihydroxyvitamin D3, was given to 19 previously untreated patients with MDS or CMML. Eight patients had to discontinue treatment before week 16 due to toxicity. According to international working group criteria, three patients (16%) responded to treatment. No correlation between VPA serum level, histone acetylation or clinical response was observed.  相似文献   
93.

Background  

The aim of the study was to examine the construct validity of the Three-Factor Eating Questionnaire -R18 (TFEQ-R18), a measure of eating behaviour, and to evaluate cognitive restraint, uncontrolled eating and emotional eating in a sample of adolescent and young adult females of different weights.  相似文献   
94.
95.
BACKGROUND: Our objective was to investigate whether serum concentrations of asymmetric dimethylarginine (ADMA) or l-arginine correlate to hyperlipidemia or endothelial function in normal pregnancy compared with the non-pregnant subjects. METHODS AND RESULTS: As a part of population-based, prospective cohort Cardiovascular Risk in Young Finns study conducted in Finland we examined 57 pregnant Finnish women throughout gestation and 62 control women matched for age and smoking. Serum glucose, triglycerides (TG), total cholesterol (TC), low-density cholesterol (LDL-C), high-density cholesterol (HDL-C) and ADMA, symmetric dimethylarginine (SDMA) and l-arginine were determined concomitantly with endothelium-dependent brachial artery flow-mediated dilation (FMD), measured by ultrasound. All serum lipid concentrations were significantly higher in pregnant women than in non-pregnant women (P < 0.001 for each). The mean serum ADMA concentration in pregnant women was significantly lower compared with the non-pregnant controls (0.513 micromol l(-1) +/- 0.0593 versus 0.577 micromol l(-1) +/- 0.0710, P < 0.001). Lowered ADMA concentrations did not correlate statistically to FMD in these healthy pregnant women but FMD was enhanced towards the end of pregnancy. CONCLUSIONS: ADMA and l-arginine concentrations fall in normal pregnancy despite marked hypercholesterolemia. Endothelium-dependent vasodilation is enhanced in normal pregnancy but is not statistically correlated to maternal serum ADMA or l-arginine concentrations.  相似文献   
96.
The aim of the present study was to evaluate pregnancy-related changes in autonomic regulatory functions in healthy subjects. We studied cardiovascular autonomic responses to head-up tilt (HUT) in 28 pregnant women during the third trimester of pregnancy and 3 months after parturition. The maternal ECG and non-invasive beat-to-beat blood pressure were recorded in the horizontal position (left-lateral position) and during HUT in the upright position. Stroke volume was assessed from blood pressure signal by using the arterial pulse contour method. Heart rate variability (HRV) was analysed in frequency domain, and baroreflex sensitivity by the cross-spectral and the sequence methods. In the horizontal position, all frequency components of HRV were lower during pregnancy than 3 months after parturition (P < 0.01 to <0.001), while pregnancy had no influence on normalized low frequency and high frequency powers. During pregnancy haemodynamics was well balanced with only minor changes in response to postural change while haemodynamic responses to HUT were more remarkable after parturition. In pregnant women HRV and especially its very low frequency component increased in response to HUT, whereas at 3 months after parturition the direction of these changes was opposite. Parasympathetic deactivation towards term is likely to contribute to increased heart rate and cardiac output at rest, whereas restored sympathetic modulation with modest responses may contribute stable peripheral resistance and sufficient placental blood supply under stimulated conditions. It is important to understand cardiovascular autonomic nervous system and haemodynamic control in normal pregnancy before being able to judge whether they are dysregulated in complicated pregnancies.  相似文献   
97.
The purpose of this cross-sectional survey was to assess patient satisfaction and analyze its relationship to nurse staffing levels in 34 inpatient wards at 4 Finnish university hospitals. The patients were satisfied with their care in general. However, the proportion of registered nurses (RNs), the patient-to-RN ratio, and the RNs' working years were highly related to patient satisfaction. Eight patients per RN was the cut-off point for patient satisfaction.  相似文献   
98.
AIM: This paper is a report of a study to assess patient knowledge about atrial fibrillation, its determinants and evolution during 3 months after a visit to the emergency room. BACKGROUND: Atrial fibrillation is one of the most common single diagnoses in the emergency room, and care often results in treatment modifications after which most patients are discharged home. METHOD: A knowledge test was developed to measure patients' knowledge of atrial fibrillation. Patient data from 200 patients were assessed by examining quartiles and medians. The statistical significance of changes was tested with the Sign test. A logistic regression model was built to identify variables possibly related to patient knowledge. The data were collected in 2003 in three emergency rooms in Finland. RESULTS: Patients had only moderate knowledge about atrial fibrillation in the emergency room, and their knowledge showed only limited improvement 3 months after the visit. They had best knowledge of the symptoms of atrial fibrillation and its effects on everyday life. There were gaps in their knowledge about this disease and how it is treated, including anticoagulation, detection of symptoms and when to seek treatment, both during the emergency room visit and 3 months thereafter. Male gender, previous atrial fibrillation diagnosis and sense of good coping with the disease were statistically significantly associated with better knowledge. CONCLUSION: Informational support should be available for patients with atrial fibrillation during and after the emergency room visit. The knowledge test introduced in this paper could be developed to evaluate the educational needs of individual patients.  相似文献   
99.
BACKGROUND: Concurrent head-to-head comparisons of healthcare interventions regarding cost-utility are rare. The concept of favorable cost-effectiveness of total hip or knee arthroplasty is thus inadequately verified. PATIENTS AND METHODS: In a trial involving several thousand patients from 10 medical specialties, 223 patients who were enrolled for hip or knee replacement surgery were asked to fill in the 15D health-related quality of life (HRQoL) survey before and after operation. RESULTS: Mean (SD) HRQoL score (on a 0-1 scale) increased in primary hip replacement patients (n = 96) from 0.81 (0.084) preoperatively to 0.86 (0.12) at 12 months (p < 0.001). In revision hip replacement (n = 24) the corresponding scores were 0.81 (0.086) and 0.82 (0.097) respectively (p = 0.4), and in knee replacement (n = 103) the scores were 0.81 (0.093) and 0.84 (0.11) respectively (p < 0.001). Of 15 health dimensions, there were statistically significant improvements in moving, usual activities, discomfort and symptoms, distress, and vitality in both primary replacement groups. Mean cost per quality-adjusted life year (QALY) gained during a 1-year period was euro 6,710 for primary hip replacement, euro 52,274 for revision hip replacement, and euro 13,995 for primary knee replacement. INTERPRETATION: Hip and knee replacement both improve HRQoL. The cost per QALY gained from knee replacement is twice that gained from hip replacement.  相似文献   
100.
Lymphoma patients often exhibit abnormal lipid metabolism. Recent evidence, however, suggests that a decrease in circulating high-density lipoprotein cholesterol (HDL-C) may occur during lymphomagenesis, reflecting underlying etiology such as inflammation. We investigated the relationship between prediagnostic HDL-C and non-Hodgkin lymphoma (NHL) in the Alpha-Tocopherol Beta-Carotene Cancer Prevention Study cohort. At baseline, serum HDL-C and total cholesterol concentrations from fasting blood, information on diet and lifestyle, and direct measurements of height, weight, and blood pressure were obtained from 27,074 healthy male smokers of ages 50 to 69 years. Cox proportional hazards models with age as underlying time metric was used to estimate relative risks (RR) and 95% confidence intervals (95% CI). We found no association between total or non-HDL cholesterol and the 201 incident NHL cases ascertained during the follow-up (1985-2002), but observed an inverse association between HDL-C and NHL, which changed with length of follow-up. High HDL-C was associated with lower risk of all NHL during the first 10 years (n = 148; RR for 5th versus 1st quintile, 0.35; 95% CI, 0.19-0.62; P(trend) < 0.0001), but not with diagnoses during later follow-up (n = 53; RR, 1.31; 95% CI, 0.55-3.10). The inverse association was similar for NHL subtypes and was not modified by obesity, blood pressure, physical activity, or alcohol intake, but seemed to be stronger in men with lower duration of smoking (P(interaction) = 0.06). Our findings implicate HDL-C as a preclinical indicator of NHL and warrant further prospective investigations for its etiologic contribution.  相似文献   
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