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AIM: The aim of the present study was to investigate the influence of endogenous estradiol and estrogen and estrogen-progestin therapies on concentration in pre- and postmenopausal women. MATERIALS AND METHODS: The study groups consisted of 26 women with surgical menopause (mean+/-standard deviation (SD): age 51.8+/-2.6 years, body mass index (BMI) 26.45+/-4.56 kg/m(2)), 54 with natural menopause (mean+/-SD: age 50.5+/-3.0 years, BMI 25.75+/-4.09 kg/m(2)) and 40 premenopausal controls (mean+/-SD: age 48.3+/-2.3 years, BMI 26.23+/-4.12 kg/m(2)). The group with surgical menopause received estradiol transdermally (50 microg/day) and those with natural menopause received additionally medroxyprogesterone acetate (5 mg/day) for the last 12 days of the cycle. Before and after 4 months of therapy, body weight, waist and hip circumferences and blood pressure were measured, and BMI and waist-to-hip ratio (WHR) were calculated. Serum leptin, follicle-stimulating hormone (FSH), estradiol (E(2)), testosterone, prolactin and dehydroepiandrosterone sulfate (DHEAS) were measured prior to and after treatment. RESULTS: Leptin concentrations did not differ statistically among the groups. No correlations between leptin and E(2), FSH, prolactin, testosterone and DHEAS concentrations were found in any of the groups before and after treatment. Leptin level correlated positively with body mass, BMI and hip and waist circumferences in all groups. There were no correlations between leptin and WHR in the pre- and postmenopausal groups. In the premenopausal group and in some postmenopausal groups, serum leptin level correlated with blood pressure. CONCLUSIONS: Endogenous E(2) and androgens in premenopausal women and estrogen and estrogen-progestin therapies in postmenopausal subjects do not influence serum leptin concentrations. Leptin level is related to body mass and BMI, but not to sex hormone status. The distribution of adipose tissue and the type of obesity (android or gynoid) have no influence on serum leptin concentration. The correlation between serum leptin level and blood pressure requires further investigation.  相似文献   
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Serum levels of bone markers N-mid osteocalcin (OCN-Mid) and Cross-Laps in 20 patients (8 men and 12 women) with loosening of at least one element of total hip endoprosthesis confirmed during operation were compared with age and sex matched group with OA. Marker levels were measured by direct chemoluminescency using Modular E-170. Statistical analysis were done with t-Student test (alpha = 0.05). There were no significant differences in OCN-Mid, Cross-Laps levels and OCN-Mid/Cross-Laps ratio between both groups. Implant loosening is a slow process taking place on a relatively small surface in comparison to whole skeleton, so bone markers have no clinical value in diagnostics of total hip loosening.  相似文献   
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Initiation constant 2kd · f, dissociation constant kd, and efficiency factor f of AIBN were measured at 60°C for two model homopolymerization systems: methyl methacrylate (MMA) in N-methyl-2-pyrrolidone (NMP) and N-vinyl-2-pyrrolidone (NVP) in methyl isobutyrate (MiB) as the solvent. The stable Banfield radical was used as inhibitor. A pronounced solvent effect was observed on the side reaction of the inhibitor with the monomers. Particular solvent sensitivity of monomers in this reaction was identified, whereby opposite solvent properties of NMP and MiB as well as of MMA and NVP were found. The initiation constant 2 kd · f depends mainly on the dissociation constant of the initiator kd in regard to its solvent dependence. The efficiency factor f is influenced by monomer concentration, stability (reactivity) of primary radicals and by viscosity of the reaction medium (solvent cage effect).  相似文献   
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The results of treatment with intrauterine transfusion are presented. The analysis comprised 48 successful transfusions into 29 foetuses. The reference group consisted of 11 transfusions which proved nonfeasible or ineffective and 54 untreated cases. Following blood treatment, the newborn mortality rate dropped more than threefold. Long-term follow-up of 21 children generally showed their good physical and mental development. We also present 4 cases of supsequent pregnancies after intrauterine blood treatment in a preceding pregnancy, showing that it is possible to save the next baby of the same mother.  相似文献   
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OBJECTIVES: To assess the effect of pain-free treadmill training on red blood cell deformability and walking distance in patients with claudication. DESIGN: Randomized-controlled trial of exercise training. SETTING: Patients were recruited from the primary care, vascular outpatient clinic. PATIENTS: A total of 60 patients with peripheral arterial occlusive disease (stage II according to Leriche-Fontaine) were randomized into the treadmill program or a control group. Fifty-five patients completed the study (27 in the exercising group and 28 in the control group). INTERVENTIONS: Patients in the exercising group were walking on the treadmill 3 times a week for 3 months. Each session consisted of 1 hour repetitive walking [performed to 85% of the pain-free walking time (PFWT)] was supervised by a qualified physiotherapist. MAIN OUTCOME MEASUREMENTS: Changes in erythrocyte deformability and treadmill walking performance (PFWT, maximal walking time) were assessed in both groups before the study and after 3 months. RESULTS: After 3 months of treadmill training, red blood cell deformability in the exercising group significantly increased (P<0.01). No significant changes were seen in the erythrocyte deformability in the control group. PFWT was prolonged by 102% from 191+/-34 to 386+/-60 seconds (P<0.01), and maximal walking time increased by 49% from 438+/-62 to 656+/-79 seconds (P<0.01) in the exercising group, whereas these changes were insignificant in the control group. CONCLUSIONS: A significant improvement of walking ability over 3 months of pain-free treadmill training is associated with a significant increase in red cell deformability in patients with claudication.  相似文献   
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