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11.
Individual differences in adolescent exercise behavior are to a large extent explained by shared environmental factors. The aim of this study was to explore to what extent this shared environment represents effects of cultural transmission of parents to their offspring, generation specific environmental effects or assortative mating. Survey data on leisure-time exercise behavior were available from 3,525 adolescent twins and their siblings (13–18 years) and 3,138 parents from 1,736 families registered at the Netherlands Twin Registry. Data were also available from 5,471 adult twins, their siblings and spouses similar in age to the parents. Exercise participation (No/Yes, using a cut-off criterion of 4 metabolic equivalents and 60 min weekly) was based on questions on type, frequency and duration of exercise. A model to analyze dichotomous data from twins, siblings and parents including differences in variance decomposition across sex and generation was developed. Data from adult twins and their spouses were used to investigate the causes of assortative mating (correlation between spouses = 0.41, due to phenotypic assortment). The heritability of exercise in the adult generation was estimated at 42%. The shared environment for exercise behavior in adolescents mainly represents generation specific shared environmental influences that seem somewhat more important in explaining familial clustering in girls than in boys (52 versus 41%). A small effect of vertical cultural transmission was found for boys only (3%). The remaining familial clustering for exercise behavior was explained by additive genetic factors (42% in boys and 36% in girls). Future studies on adolescent exercise behavior should focus on identification of the generation specific environmental factors.  相似文献   
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The LH-RH test was performed in 62 mainly prepuberal children. A dose of 25 mug/20 kg was given intravenously between 10 and 12a.m. Prepuberal healthy boys between 1 11/12 and 9 7/12 years of age reacted with a fourhold increase of LH. Prepuberal boys with an unilaterally undescended testicle showed no difference in LH response from normal. Even a low increase in LH may be followed by spontaneous puberty in children with pituitary dwarfism. The LH response in children with craniopharyngeoma was heterogeneous and appeared to depend on location of tumor and extent of operation. Birdheaded dwarfism and small stature due to steroid administration and due to unknown etiology showed normal LH responses for age. Cases with anorchia and myotonic dystrophy had an excessive LH increase. The LH response in children with Fanconi's anemia and undescended testicles and in otherwise healthy boys with undescended testicles was normal for age. A case of untreated adrenogenital syndrome without salt loss had a presumably normal increase of LH when related to bone age. Primary and pituitary hypothyroidism was shown to have a higher than normal output of LH. A boy with a tumor the 3rd ventricle hat basal levels of LH that were extremely elevated and associated with precocious puberty and diabetes insipidus. A newborn infant with anencephalus showed no increase of LH and LH-RH injection.  相似文献   
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The treatment of cryptorchidism should start at the age of two years because of pathological and anatomical studies. Ectopic testicles, inguinal hernias and postoperative situations associated with a wrong position of the testicle are primary indications for surgical corrections. Fixed inguinal, retractile or abdominal testicles may be primarily treated with human chorionic gonadotropin (HCG). The success rate after medical treatment averages 50%. The intranasal application of the releasing hormone of luteotropic hormone (LH-RH) may represent an alternative approach to the treatment of cryptorchidism. If treatment with LH-RH is to obtain the same success rate as HCG in larger series it may combine the advantage of painlessness with no androgenic side effects.  相似文献   
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Background  

The Dutch Consumer Quality Index Hip Knee Questionnaire (CQI Hip Knee) was used to assess patients' experiences with and evaluations of quality of care after a total hip (THA) or total knee arthroplasty (TKA). The aim of this study is to evaluate the construct validity and internal consistency reliability of this new instrument and to assess its ability to measure differences in quality of care between hospitals.  相似文献   
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OBJECTIVE: To determine whether a goal-directed terlipressin infusion increases mean arterial pressure without causing a pulmonary vasopressive effect and whether this response impacts on key parameters of oxygen transport in healthy and endotoxemic sheep. DESIGN AND SETTING: Prospective controlled trial in a university research laboratory. ANIMALS AND INTERVENTIONS: Six conscious adult ewes instrumented for chronic study received terlipressin as titrated infusion started with 10 microg x kg(-1) x h(-1) and increased by 5 microg x kg(-1) x h(-1) every 15 min, either until mean arterial pressure was increased by 15 mmHg from baseline, or a maximum of 40 microg x kg(-1) x h(-1) was given. Following 24 h of recovery sepsis was induced and maintained in the same ewes by a continuous infusion of endotoxin ( Salmonella typhosa, 10 ng x kg(-1) min(-1)). After 16 h of endotoxemia the sheep were again treated with terlipressin. MEASUREMENTS AND RESULTS: Systemic oxygen delivery and consumption were calculated before and after the titration period; hemodynamic parameters were measured every 15 min. The increase in mean arterial pressure was greater during endotoxemia than in healthy controls. In both states terlipressin administration decreased cardiac index and diminished oxygen delivery and consumption. While mean pulmonary arterial pressure remained constant, terlipressin increased the pulmonary vascular resistance index in endotoxemic sheep. CONCLUSIONS: During ovine endotoxemia titrated terlipressin reversed hypotension but impaired the pulmonary circulation. The observed decrease in oxygen delivery may carry the risk of tissue hypoxia especially in sepsis, where oxygen demand is typically increased.  相似文献   
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In this article we propose developmentally informed remedies to the challenges that face research training. The initiatives described in it have been implemented to various degrees at our institution, and several are already being replicated or expanded through strategic partnerships across the country. We are fortunate to work in an environment in which child and adolescent psychiatry is visible and well represented, but we are aware than many of the settings in which education and recruitment needs are most pressing may not have the range of our resources. We view our different programs as seamlessly interconnected with one another but present them as separate entities to facilitate the incorporation of different components into local realities.  相似文献   
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BACKGROUND AND OBJECTIVES: Thoracic epidural analgesia (TEA) is increasingly used for perioperative analgesia. If patients with TEA develop sepsis or systemic inflammatory response subsequent to extended surgery the question arises if it would be safe to continue TEA with its beneficial effects of improving gastrointestinal perfusion and augmenting tissue oxygenation. A major concern in this regard is hemodynamic instability that might ensue from TEA-induced vasodilation. The objective of the present study was to assess the effects of TEA on systemic and pulmonary hemodynamics in a sepsis model of hyperdynamic endotoxemia. METHODS: After a baseline measurement in healthy sheep (n = 14), Salmonella thyphosa endotoxin was continuously infused at a rate of 10 ngxkg(-1)xmin(-1) over 16 hours. The surviving animals (n = 12) were then randomly assigned to 1 of 2 study groups. In the treatment group (n = 6), continuous TEA was initiated with 0.1 mLxkg(-1) bupivacaine 0.125% and maintained with 0.1 mLxkg(-1)xh(-1). In the control group (n = 6) the same amount of isotonic sodium saline solution was injected at the same rate through the epidural catheter. RESULTS: In both experimental groups cardiac index increased and systemic vascular resistance decreased concurrently (each P < .05). Functional epidural blockade in the TEA group was confirmed by sustained suppression of the cutaneous (or panniculus) reflex. During the observational period of 6 hours neither systemic nor pulmonary circulatory variables were impaired by TEA. CONCLUSIONS: From a hemodynamic point of view, TEA presents as a safe treatment option in sepsis or systemic inflammatory response syndrome.  相似文献   
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