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Summary The 1-adrenoceptor subtypes of dog prostate were characterized in binding and functional experiments. In saturation experiments, [3H]prazosin bound to 1-adrenoceptors with high affinity. In the displacement experiments, unlabelled prazosin and WB4101 biphasically inhibited the binding of 400 pM [3H]prazosin, suggesting the presence of at least two distinct affinity sites for prazosin or WB4101. The proportion of high-affinity sites was approximately 10%. HV723 also recognized two distinct affinity sites but the proportion of high-affinity sites was approximately 20%. From these results the presence of three distinct 1-adrenoceptor subtypes was suggested: presumably subtypes 1A (high affinity for prazosin and WB4101), 1N (high affinity for only HV723) and 1L (low affinity for the three antagonists) according to the recently proposed 1-adrenoceptor subclassification. The density of subtype 1L was much higher than that of subtypes 1A and 1N subtypes. In the functional experiments, prazosin, WB4101 and HV723 competitively antagonized the contractile response to noradrenaline with low affinities close to those estimated for the 1L subtypes. These results suggest that the contractile response to noradrenaline in the dog prostate is mediated predominantly through 1L subtype -adrenoceptors.  相似文献   
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It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk factors in relation to severity and physical fitness is still controversial. Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods. Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program, their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05) without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05). Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness.  相似文献   
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CONTEXT: Pregnant women are exempted from the current seatbelt legislation in Japan despite the fact that seatbelt use is essential to reduce the risk of fatalities for these women and their fetuses in car crashes. OBJECTIVE: To examine factors that might influence seatbelt use during pregnancy. METHODS: A cross sectional study, with data collected via an anonymous, self administered questionnaire at obstetric clinics in suburban areas of Japan. Altogether 880 pregnant women receiving prenatal care in July 2001 were recruited. The relative effects of factors that might influence seatbelt use during pregnancy were estimated using logistic regression analysis. RESULTS: Almost 70%-80% of pregnant women were consistent seatbelt wearers before pregnancy but seatbelt compliance was reduced by about half at 20 weeks or more gestation. Only 20% had received information on maternal seatbelt use, with one third reporting that seatbelt use is beneficial during pregnancy. Those who perceived that maternal seatbelt use is beneficial tended to maintain use, but daily car users and those who knew that they were exempted from seatbelt legislation were more likely to reduce use. CONCLUSIONS: Knowledge of the legislative exemption for pregnant women, misunderstanding of the benefits, and daily car use contributed to the reduction in seatbelt use after pregnancy.  相似文献   
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Low molecular weight heparins are significantly superior to unfractionated heparin or warfarin in the prevention of thromboembolic episodes associated with orthopaedic surgery. Therapeutic doses of heparin and warfarin have been shown to delay bone repair in a rabbit model. The current study investigated the effect of prophylactic administration of a low molecular weight heparin, enoxaparin, on the healing of a closed rabbit rib fracture. Fracture healing was assessed using histomorphometric, histologic, and immunohistochemical methods at 3, 7, and 14 days, and biomechanical testing with torsional loading was assessed after 21 days. Bone repair was significantly attenuated at all times in animals receiving subcutaneous enoxaparin compared with that of the control animals. Numerous putative mechanisms for this phenomenon are discussed, and additional studies are proposed to elucidate the effects of this pharmacologically diverse group of compounds on all aspects of bone physiology and repair.  相似文献   
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OBJECTIVE: To measure the seroprevalence of human immunodeficiency virus (HIV) infection and syphilis, and to assess the behavioural risk factors for these infections among migrant-returnees and non-migrants in far western Nepal. METHODS: In April 2001, we recruited 97 male migrant-returnees and 40 non-migrants from five rural villages in Doti district where migration to Mumbai is common. For data collection, we conducted a serological examination for HIV and syphilis, and a perception and behaviour survey on HIV and other sexually transmitted infections. RESULTS: We found that 11 of 137 men (8%) were positive for HIV infection and 30 men (22%) for syphilis. The respondents, especially the migrant-returnees from Mumbai, were engaging in risky behaviours such as pre- or extramarital sex, and sex with multiple partners, including sex workers. CONCLUSIONS: This study revealed high HIV and syphilis prevalence among the male migrant-returnees and non-migrants in far western Nepal where migration to Mumbai is common. The prevalent behaviours, particularly among the migrant-returnees, imply urgent needs of the behavioural modification programme in this area to prevent the spread of HIV infection to general population.  相似文献   
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The risk of vertical transmission of hepatitis C virus (HCV) from mother to infant has been well documented, but the exact mode of transmission is still unclear. In a set of monochorionic diamniotic monozygous twins, only the second baby was infected with HCV from the mother who was positive for serum HCV-RNA. The babies had an uncomplicated vaginal delivery 3 min apart and they were both bottle fed from the outset. The second baby developed clinical hepatitis that persisted to 30 months follow up. The intrauterine environment should have been identical for these twins, and therefore, the maternal HCV factors, including viral load are not the sole determining factors for mother-to-infant transmission of HCV.  相似文献   
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