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The present study completed a previous randomized trial that demonstrated the protective effect of 1-year psoas training on lumbar bone loss in postmenopausal women. Computerized tomography had been carried out at the beginning (CT1) and at the end (CT2) of this trial. In the present study, 67 women having completed the first trial were asked to practice psoas exercises (60 hip flexions in sitting position with a 5 kg weight on the knee) for 2 additional years with a third CT control at the end of this period (CT3). The aim of this complementary study was to assess the compliance rate and long-term effect on bone of daily psoas muscle training over a longer period. Twenty-one women performed this daily psoas training for 3 years from CT1 to CT3, and 14 acted as controls during the same period. Fourteen women were controls during the first year (from CT1 to CT2) but practiced psoas training during the following 2 years (from CT2 to CT3). Four women were psoas trained during the first year (from CT1 to CT2) and subsequently crossed over to the control group for the last 2 years. The compliance rate was 42%, with an attendance rate of 88%. The lumbar bone loss was lower in the 21 women trained over the 3 years (−3.26 ± 28.45 mg/cm3) than in the 14 untrained women (−16.79 ± 8.51 mg/cm3) (P= 0.02). The bone loss was not significantly reduced between the two periods of the study in the 12 women having been controls from CT1 to CT2 and having crossed over to the active training group from CT2 to CT3. Psoas training may be effective against lumbar bone loss. We conclude that specific training may play a contributing role in the preventive strategy to avoid osteoporosis. Received: 23 February 1996 / Accepted: 25 October 1996  相似文献   
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In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients.  相似文献   
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Several authors have discussed an alteration of adrenergic receptivity in arterial hypertension. De Champlain (Hypertension 1990; 8: S77-S85) suggested that postsynaptic alpha 1-adrenergic functions became dominant while beta-adrenergic functions are attenuated in arterial hypertension. However, the status of presynaptic alpha 2-adrenoceptors remains unknown. The present study investigates presynaptic alpha 2-adrenoceptors in hypertension through the measurement of plasma levels of noradrenaline after administration of yohimbine, an alpha 2-adrenoceptor antagonist, in essential hypertension. Yohimbine (0.2 mg/kg per os) induced a 73% increase of plasma levels of noradrenaline in hypertensive patients (n = 12) and a 178% one in normotensive subjects (n = 6, p < 0.05). A similar significant difference was found in experimental neurogenic hypertension observed in awake dogs 3 weeks after sinoaortic denervation: the increase in plasma concentrations of noradrenaline after yohimbine (0.5 mg/kg i.v.) was +279% in hypertensive versus +642% in normotensive dogs (p < 0.05). The results show that the magnitude of the yohimbine-induced sympathetic activation is lower in hypertensives than in normotensives. They suggest the existence of a presynaptic alpha 2-adrenoceptor desensitization in arterial hypertension. The abnormality of this presynaptic inhibitory mechanism can increase the sympathetic tone and help to develop and maintain arterial hypertension.  相似文献   
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INTRODUCTION: Broncholithiasis is often seen after chronic granulomatous diseases such as tuberculosis and hystoplasmosis and leads to a wide spectrum of signs and symptoms; including hemoptysis which often needs surgical management. The goal of this study is evaluation of surgery in patients with tuberculous broncholithiasis who present with hemoptysis. MATERIALS AND METHODS: In this study all patients with tuberculous broncholithiasis had been operated on between 1991 and 2005, followed up at least 6 months and at most 9 years, and studied relating to age, sex, clinical symptoms, diagnostic methods, type of surgical treatment, complications and mortality. RESULTS: Overall 5 patients have been studied (male:female=2:3, mean=31 years); 2 with severe and 3 mild to moderate and recurring hemoptysis, lesion at left in 80% and at right in 1, in 3 patients some degree of bronchiectasia was seen, in 4 the lesion was visible in bronchoscopy and endoscopic removal of the lesion failed in all. Three of patients underwent pulmonary resections and in 2 broncholithotomy has been done. In follow-up, patients treated with pulmonary resection have had no subsequent problems, but in patients treated with broncholithotomy due to occurring late bronchiectasia, re-operation and pulmonary resection was inavoidable. There was no mortality. CONCLUSION: Regarding the dangers of hemoptysis and excellent results of surgery and possible occurance of late bronchiectasia after broncholithotomy, the results of our study show that pulmonary resection distal to the lesion and as the retention of lung of parenchyma is preferable. Broncholithotomy should be done only in patients in whom pulmonary resection is not technically possible. Because of the very low occurance of this complication complete studies are needed.  相似文献   
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The nitric oxide pathway in pre-eclampsia: pathophysiological implications   总被引:2,自引:0,他引:2  
Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with NG-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.  相似文献   
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Male genital tract obstructions may result from infections, previous inguinal and scrotal surgery (vasectomy) and congenital bilateral absence of the vas deferens (CBAVD). Microsurgery can sometimes be successful in treating the obstruction. In other cases and in cases of failed surgical intervention, the patient can be treated by microsurgical or percutaneous epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). We present the results of 39 ICSI procedures for obstructive azoospermia in 24 couples. The aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD in nine and genital infections in four. Sperm retrieval was accomplished via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was only applied when PESA failed to produce enough spermatozoa for simultaneous ICSI. In six patients, the ICSI procedure was performed with cryopreserved spermatozoa after an initial PESA procedure. Fertilization occurred in 47% of the metaphase II oocytes; embryo transfer was performed in 92% of procedures and resulted in a clinical pregnancy in 13/39 procedures. Ongoing pregnancy was achieved in 10/39 procedures. One pregnancy was terminated early after prenatal investigation showed a cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine pregnancies resulted in the live birth of 10 children, without any congenital abnormalities. Epididymal and testicular retrieved spermatozoa were successfully used for ICSI to treat obstructive azoospermia, and resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI procedures, a success rate of 25.6% per treatment cycle and of 27.7% per embryo transfer.   相似文献   
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