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The relation between sexual function and serum free testosterone (fT) levels, which represent the active fraction of circulating testosterone, was evaluated. Two groups of impotent male subjects with mild hypogonadism were treated with oral testosterone undecanoate (TU); these men presented with tT/luteinizing hormone (LH) ratio and tT levels at the lower limits of normal. The first group had serum fT below 6.6 ng/ml, considered the lower normal value, according to our laboratory method, whereas the second group had normal fT limits. Administration of TU improved sexual function only in impotent men with low fT levels, but not in subjects with normal fT levels, even though the tT levels and the tT/LH ratio of the two groups were not significantly different. The results of our study suggest the presence of a minimun serum fT threshold, lying near the lower normal range, which determines the male sexual function. Moreover, serum fT levels were a more sensitive index than tT for identifying impotent men who can be successfully treated with androgens.  相似文献   
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Cardiac transplantation was resumed at the University Health Center of Pittsburgh in 1980 after a hiatus of 12 years. Prior to April 15, 1986, 270 hearts had been transplanted. Participants have been forced to reorder personal, professional, and institutional commitments to adapt to new demands of pre- and post-operative care and to develop flexibility in the operative scheduling of routine cardiac surgical cases. The actuarial survival has been 78, 69, and 64% at 1, 2, and 3 years. Much has been learned about evolving immunosuppression based on cyclosporine and of the allogenic response. An increasing proportion of recipients are mortally ill (54%), and for these urgent patients the wait for a donor organ continues to lengthen. The cardiac surgeon performing transplantations will need to grow with allied developments in xenotransplantation and mechanical cardiac support devices in order to keep pace with his evolving specialty.  相似文献   
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Although observational studies suggest that hyperhomocysteinemia may be a risk factor for coronary allograft vasculopathy (CAV), prospective data on homocysteine-lowering interventions and CAV development are lacking. We, therefore, randomized 44 de novo heart transplant (HT) recipients to 15 mg/day of 5-methyl-tetrahydrofolate (n=22), or standard therapy (control group, n=22) to investigate the effect of homocysteine lowering on the change in coronary intimal hyperplasia during the first 12 months after transplant, as detected by intra-vascular ultrasound (IVUS). Although 12 months after HT, homocysteinemia was lower in folate-treated patients (p<0.001), coronary intimal area increased similarly in the two groups (p>0.4). Conversely, hypercholesterolemia and cytomegalovirus infection were both associated with increased intimal hyperplasia (p<0.04), independently from folate intake. Sub-group analysis revealed that folate therapy reduced intimal hyperplasia in patients with hyperhomocysteinemia before randomization (n=19; p=0.02), but increased intimal hyperplasia in patients with normal homocysteine plasma concentrations (p=0.02). This bimodal effect of folate therapy persisted significantly after adjusting for cytomegalovirus infection and hypercholesterolemia. Despite effective in prevent hyperhomocysteinemia after heart transplantation, folate therapy does not seem to affect early CAV onset. However, sub-group analysis suggests that folate therapy may delay CAV development only in patients with baseline hyperhomocysteinemia, while may favor CAV progression in recipients with normal baseline homocysteinemia.  相似文献   
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Tropical pyomyositis is an infection of muscles mainly presenting in black people, occurring in the trunk and limbs. At Hoima Hospital, Uganda, 58 patients (30 men and 28 women) with a mean age of 21 years have been investigated by ultrasound; a total of 81 lesions were present. Two different characteristic images were found; abscess was present in 65 cases while 16 patients showed a diffuse infiltration among the muscular fibers. These two different images correspond to the two stages of histologic and clinical progression described by other authors. Ultrasound is useful to demonstrate the progression of pyomyositis and to determine when and where to drain any abscess.  相似文献   
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The quality of health care systems and processes is becoming a prominent problem and more and more efforts are devoted to define methodologies and tools to measure and assure quality of care. New methods are required to optimize health care processes to guarantee high quality standards within (limited) available resources. Resource optimizations able to preserve the quality of treatments require good models of medical processes. This paper presents LEMMA, a new notation to model medical processes. LEMMA provides physicians with intuitive graphical elements to design their models. At the same time a high level timed Petri net corresponding to the designed model is built automatically. In this way, LEMMA models are ascribed formal semantics and can be executed and analyzed automatically. The dual language approach followed in this paper allows physicians to gain all the benefits of formal methods without being proficient in them. Medical users manage simple graphical elements, while Petri nets ensure formality and validation capabilities. In this way LEMMA mixes formal and informal notations, overcoming the problems of both the approaches. The definition of the notation has been supported by the development of an environment to design LEMMA models. The environment, besides letting us experiment with the notation, has been employed to define and analyze real case studies.  相似文献   
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We used monoclonal antibodies and immunohistochemical staining of frozen tissue sections to study the expression of cytokines in human cardiac allograft rejection. The 113 endomyocardial biopsy samples were stained for interleukin (IL)-2, IL-6, and interferon-gamma. The findings were compared to expression of the endothelial cell adhesion molecule ICAM-1, and the lymphocyte receptor for the adhesion molecule VCAM-1, VLA-4. Four biopsy samples from patients with idiopathic cardiomyopathy served as controls. IL-2 was not expressed in lymphocytes of controls and only occasionally in mild or moderate cellular rejection, humoral rejection, and Quilty lesions. IL-2 expression was prominent in severe cellular rejection. Interferon-gamma expression increased in proportion to the severity of cellular rejection and was not expressed in other conditions. IL-6 staining, which was only observed in occasional cases, was mild. Cytokine and adhesion molecule expression tended to increase with the severity of cellular rejection. This study shows that cytokine expression can be documented in human allograft endomyocardial biopsy samples with immunohistochemical techniques. The findings support the concept of an important role for cytokines in human cardiac allograft rejection.  相似文献   
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AIMS: Scarcity of resources, expertise and evidence-based models have so far limited delivery of patient-centred diabetes education. We have developed and validated a group care approach that is applicable to everyday clinical practice and cost-effective in improving metabolic control, knowledge of diabetes, health behaviours, and quality of life in Type 2 diabetes. A clinical trial (ROMEO) was planned to evaluate applicability and reproducibility of group care in other outpatients facilities and assess its impact on a larger patient population. METHODS: Multicentre, randomized, controlled clinical trial of group vs. individual care in the routine management of Type 2 diabetes. Nine hundred patient aged < 80, with diabetes of > or =1 year known duration, treated by either diet alone or diet and oral agents, will be recruited in 15 centres and followed for 4 years. Training of physicians, nurses and dietitians included preparation of operating manual and videos, interactive sessions, and evaluation of local facilities and resources. RESULTS: Primary measurements: 3-monthly HbA1c, fasting blood glucose, body weight, waist-hip ratio, yearly blood lipids, and bi-yearly assessment of knowledge of diabetes, health behaviours and quality of life. Secondary outcomes: systolic and diastolic blood pressure, evaluation of ECG for ischaemia and QT interval, hypoglycaemic and anti-hypertensive medication and cardiovascular events. Analysis will be by intention-to-treat. DISCUSSION: If ROMEO confirms that group care can be successfully implemented in different clinics, a novel clinico-pedagogic tool will have been acquired to support patient-centred education, improve lifestyle and outcomes, support team work, enhance providers' attitudes and competencies and ameliorate diabetes care organization.  相似文献   
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