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911.
BACKGROUND: In contrast to chemotherapy, previous irradiation of the uterus carries an increased risk of an adverse pregnancy outcome. Conflicting results exist as regards the ability of the uterus to increase in volume following radiotherapy-induced damage. We measured uterine volume in a cohort of childhood cancer survivors, and assessed uterine response to a high-dose estrogen replacement regimen. METHODS: Uterine volume was assessed by transvaginal sonography in 100 childhood cancer survivors. Three patients with ovarian failure and severely reduced uterine volume following abdominal or pelvic irradiation were treated with percutaneous estradiol 150 microg/24 h for three cycles, and transvaginal uterine sonography was repeated monthly. RESULTS: Uterine volume was significantly reduced in nulliparous patients who had received direct uterine irradiation (n = 13; median 13 mL, range 1-52 mL) compared with nulliparous patients who had received chemotherapy only (n = 37; 47 mL, 22-88), radiotherapy above the diaphragm (n = 17; 40 mL, 24-61), or radiotherapy below the diaphragm not directly involving the uterus (n = 13; 34 mL, 8-77) (p < 0.02 in all comparisons). Among nulliparous patients a significant correlation was found between age at direct uterine irradiation and uterine volume (r = 0.78, p = 0.002). No significant improvement in uterine volume, endometrial thickness or uterine artery blood flow was observed in three hypogonadal patients in response to high-dose estrogen replacement therapy. CONCLUSIONS: Our results indicate that cytotoxic treatment in childhood does not affect adult uterine size. In contrast, uterine irradiation at a young age reduces adult uterine volume. The radiotherapy-induced damage is probably irreversible.  相似文献   
912.
OBJECTIVE: Defects in insulin secretion and insulin action are the major abnormalities in the development of type 2 diabetes. In middle-aged subjects, elevated plasma proinsulin has been found to predict type 2 diabetes. Therefore, our aim was to study the longitudinal relationships between baseline determinations of insulin sensitivity index (S(i)) assessed by euglycemic insulin clamp, the early insulin response (EIR) at an oral glucose tolerance test (OGTT), fasting intact proinsulin, 32-33 split proinsulin and specific insulin, and the development of type 2 diabetes in a population-based cohort of 70-year-old nondiabetic men (n = 667) with 7-year follow-up. RESEARCH DESIGN AND METHODS: A euglycemic insulin clamp study and a 75-g OGTT were performed at baseline, and fasting peptide concentrations were measured using specific two-site immunometric assays. Results from logistic regression models are presented as odds ratios (ORs) with 95% CIs for a 1-SD increase in the predictor variable. RESULTS: In separate multivariate analyses adjusted for EIR (OR 0.72, 95% CI 0.59-0.89) and S(i) (0.68, 0.58-0.88), 32-33 split proinsulin (1.49, 1.18-1.88) or intact proinsulin (1.30, 1.04-1.63) were significantly associated with the development of type 2 diabetes, whereas specific insulin (1.24, 0.91-1.66) was not. The significant associations between 32-33 split or intact proinsulin and the development of type 2 diabetes were unaltered after adjustment for BMI and glucose tolerance. CONCLUSIONS: Insulin propeptides predicted type 2 diabetes over a 7-year period in elderly men, independent of the EIR and S(i).  相似文献   
913.
OBJECTIVE: It is clinically important to find noninvasive markers of insulin resistance and hyperproinsulinemia because they both predict cardiovascular and diabetes risk. Sagittal abdominal diameter (SAD) or "supine abdominal height" is a simple anthropometric measure previously shown to predict mortality in men, but its association with insulin resistance and hyperproinsulinemia is unknown. RESEARCH DESIGN AND METHODS: In a common high-risk group of 59 moderately obese men (aged 35-65 years, BMI 32.6 +/- 2.3 kg/m(2)), we determined anthropometry (SAD, BMI, waist girth, and waist-to-hip ratio [WHR]); insulin sensitivity (euglycemic-hyperinsulinemic clamp); and plasma concentrations of intact proinsulin, specific insulin, C-peptide, glucose, and serum IGF binding protein-1 (IGFBP-1). To compare SAD with other anthropometric measures, univariate and multiple regression analyses were used to determine correlations between anthropometric and metabolic variables. RESULTS: SAD showed stronger correlations to all measured metabolic variables, including insulin sensitivity, than BMI, waist girth, and WHR. SAD explained the largest degree of variation in insulin sensitivity (R(2) = 0.38, P < 0.0001) compared with other anthropometric measures. In multiple regression analyses, including all anthropometric measures, SAD was the only independent anthropometric predictor of insulin resistance (P < 0.001) and hyperproinsulinemia (P < 0.001). CONCLUSIONS: In obese men, SAD seems to be a better correlate of insulin resistance and hyperproinsulinemia (i.e., cardiovascular risk) than other anthropometric measures. In overweight and obese individuals, SAD could represent a simple, cheap, and noninvasive tool that could identify the most insulin resistant in both the clinic and clinical trials evaluating insulin sensitizers. These results need confirmation in larger studies that also include women and lean subjects.  相似文献   
914.
OBJECTIVES: Pathomechanisms of work-related myalgia are poorly understood. Myalgia is thought to be caused by excitation of nociceptors present in the muscular tissue but not in the muscle fiber itself. Muscle contraction in combination with hypoxia is known to excite nociceptors. Morphologic analysis can contribute to the knowledge of the excitation of nociceptors. This study thoroughly examines the morphology of the trapezius muscle's capillary supply and signs of disturbed oxidative metabolism to understand their role in work-related myalgia. METHODS: Surgical trapezius muscle biopsies were obtained from 25 female cleaners with long-standing work-related myalgia, 25 female cleaners without trapezius myalgia, and 21 healthy teachers. Enzyme and immunohistochemical stainings were performed to highlight fibers with aberrant intermyofibrillar patterns, indicating a disturbed oxidative metabolism (also known as moth-eaten fibers) and a disturbed capillary supply of different fibers. RESULTS: A significantly lower number of capillaries per fiber area in cleaners suffering from myalgia compared with cleaners without trapezius myalgia was found. Moth-eaten fibers were found in the 3 groups, but these fibers were significantly more prevalent in the groups of cleaners than in the healthy teacher group. CONCLUSION: This work indicates that the capillary supply of trapezius is affected in work-related trapezius myalgia. More studies are needed to understand possible mechanisms that would explain the occurrence of moth-eaten fibers.  相似文献   
915.
916.
Organization and control research has largely focused on the reform work and changes in the public sector. Many studies have focused on the reasons for reforms rather than on their significance. In this article, the authors deal with a control model applied in maternity health and based on remuneration for performance. At the end of the article, the authors note that formal control models are significant. Staff members have adapted to the model, but the model has also been adjusted to suit reality. This change has meant intentional effects, in the sense that the work has been adapted to suit the conditions given, but also unintentional effects in the form of attempts to outwit the system.  相似文献   
917.
BACKGROUND: Needlestick injuries confer an unnecessary risk of occupational bloodborne infections such as human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. After an accidental needlestick injury, procedures for inoculation of liquid culture media for rapid detection of Mycobacterium tuberculosis complex and other mycobacteria from blood and bone marrow specimens were reviewed. AIM: To identify a safer transfer device, which could replace the ordinary syringe in inoculation of liquid culture vials. METHODS: We identified a transfer device to transfer blood or bone marrow specimens from bedside tubes into liquid culture vials. CONCLUSION: The changed procedure will reduce the risk of needlestick accidents and be of benefit to other microbiological laboratories using the same or similar inoculation techniques.  相似文献   
918.
BACKGROUND: Deficiencies of iron and zinc are associated with delayed development, growth faltering, and increased infectious-disease morbidity during infancy and childhood. Combined iron and zinc supplementation may therefore be a logical preventive strategy. OBJECTIVE: The objective of the study was to compare the effects of combined iron and zinc supplementation in infancy with the effects of iron and zinc as single micronutrients on growth, psychomotor development, and incidence of infectious disease. DESIGN: Indonesian infants (n = 680) were randomly assigned to daily supplementation with 10 mg Fe (Fe group), 10 mg Zn (Zn group), 10 mg Fe and 10 mg Zn (Fe+Zn group), or placebo from 6 to 12 mo of age. Anthropometric indexes, developmental indexes (Bayley Scales of Infant Development; BSID), and morbidity were recorded. RESULTS: At 12 mo, two-factor analysis of variance showed a significant interaction between iron and zinc for weight-for-age z score, knee-heel length, and BSID psychomotor development. Weight-for-age z score was higher in the Zn group than in the placebo and Fe+Zn groups, knee-heel length was higher in the Zn and Fe groups than in the placebo group, and the BSID psychomotor development index was higher in the Fe group than in the placebo group. No significant effect on morbidity was found. CONCLUSIONS: Single supplementation with zinc significantly improved growth, and single supplementation with iron significantly improved growth and psychomotor development, but combined supplementation with iron and zinc had no significant effect on growth or development. Combined, simultaneous supplementation with iron and zinc to infants cannot be routinely recommended at the iron-to-zinc ratio used in this study.  相似文献   
919.
BACKGROUND: The 5,10-methylenetetrahydrofolate reductase gene (MTHFR) 677C-->T polymorphism modifies the risk of coronary artery disease and colon cancer and is related to plasma concentrations of total homocysteine (tHcy). Riboflavin status modifies the metabolic effect of the polymorphism, and thyroid hormones increase the synthesis of flavin cofactors. OBJECTIVE: The aim of the study was to investigate the phenotypic expression of the MTHFR 677C-->T polymorphism in terms of plasma tHcy concentrations in patients with thyroid dysfunction. DESIGN: The study population consisted of 182 patients with hyperthyroidism. We studied plasma tHcy in relation to MTHFR genotype, riboflavin, and folate before and during 6 mo of treatment with antithyroid drugs. RESULTS: Before treatment, tHcy was higher in patients with the mutant enzyme than in those with the wild-type enzyme. A genotype effect was observed only at low riboflavin or folate concentrations (P T polymorphism, possibly by modifying the availability of flavin cofactors.  相似文献   
920.
AIM: The authors sought to describe risk indicators of long-term sick leave during pregnancy among hospital employees. METHODS: A register-based study was undertaken of 4,852 female hospital employees aged 20-45 years from the second largest hospital in Denmark during 1995-99 based on job titles, working time, sick leave, and births combined with a survey among a total of 773 women who had been pregnant during their employment (response rate 85%). RESULTS: Altogether 236 (31%) were on sick leave for at least 10% of their scheduled work time during their latest pregnancy and 169 (22%) had been absent at least 20% of the time. The pregnant women had an average sickness absence of 6.1 days per month, non-pregnant women 0.95 days per month. Sick leave was more frequent in late than in early gestation. Women employed as nursing aides or hospital orderlies, launderers, and nurses had more sick leave days than other hospital employees. Part-time work, previous sickness absence not related to pregnancy, and previous chronic back pain were risk factors for long-term sick leave as were much walking or standing, long working days, high work level, little practical support from supervisors and colleagues, low job control, much lifting and night or shift work. Sick leave was unrelated to family size, support from the family and number of working years. CONCLUSION: Long-term sick leave during pregnancy was frequent and to some extent predictable. Efforts should be made to organize work for pregnant women in a manner that optimizes their health and well-being.  相似文献   
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