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The occurrence and duration of the carrier state in familial associates of recognized cases of poliomyelitis was studied by the examination for virus of stool specimens collected from the members of four families at regular intervals for a period of over 2 months. The results indicate that: (1) virus may persist in their stools continuously for 4 to 5 weeks; (2) virus may be encountered intermittently in the stools; (3) in some instances virus may be present for brief periods only; (4) children are more likely to maintain virus than are adults in the same family; (5) infection of a family takes place rapidly, suggesting again simultaneous infection from a common source.  相似文献   
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OBJECTIVES: This study determines the risk of ipsilateral ischaemic neurological events in relation to the degree of asymptomatic carotid stenosis and other risk factors. METHODS: Patients (n=1115) with asymptomatic internal carotid artery (ICA) stenosis greater than 50% in relation to the bulb diameter were followed up for a period of 6-84 (mean 37.1) months. Stenosis was graded using duplex, and clinical and biochemical risk factors were recorded. RESULTS: The relationship between ICA stenosis and event rate is linear when stenosis is expressed by the ECST method, but S-shaped if expressed by the NASCET method. In addition to the ECST grade of stenosis (RR 1.6; 95% CI 1.21-2.15), history of contralateral TIAs (RR 3.0; 95% CI 1.90-4.73) and creatinine in excess of 85 micromol/L (RR 2.1; 95% CI 1.23-3.65) were independent risk predictors. The combination of these three risk factors can identify a high-risk group (7.3% annual event rate and 4.3% annual stroke rate) and a low risk group (2.3% annual event rate and 0.7% annual stroke rate). CONCLUSIONS: Linearity between ECST per cent stenosis and risk makes this method for grading stenosis more amenable to risk prediction without any transformation not only in clinical practice but also when multivariable analysis is to be used. Identification of additional risk factors provides a new approach to risk stratification and should help refine the indications for carotid endarterectomy.  相似文献   
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The objective of this study was to evaluate the epidemiology, diagnosis, pathophysiology, and treatment of bone loss related to anorexia nervosa. Earlier onset and longer duration of anorexia nervosa are associated with more severe bone loss. Osteoporosis develops in 38 to 50% of cases. Bone mineral density measurement by dual-energy X-ray absorptiometry is useful for assessing bone mass, and bone marker assays provide information on bone turnover. Bone loss in anorexia nervosa is probably multifactoriel. Estrogen deficiency was long felt to be the major factor. However, in contrast to postmenopausal osteoporosis, bone loss associated with anorexia nervosa is related mainly to inadequate bone formation, with only a slight increase in bone resorption. This suggests a role for nutritional factors, such as disturbances in the growth hormone-somatomedin C axis (GH/IGF-I) related to malnutrition. The best treatment strategy for correcting bone mass in patients with anorexia nervosa is not agreed on. Resumption of menstrual cycles and weight gain seem necessary but not always sufficient. Studies found no benefits with estrogen therapy, but this was usually given as estrogen–progestin contraceptives. No vast studies evaluating hormone replacement therapy have been reported. Bone formation enhancers such as IGF-I seem to provide the best results, most notably when used in combination with estrogens. This suggests that complex treatment strategies combining bone formation enhancers and bone resorption inhibitors may deserve evaluation.  相似文献   
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We performed a prospective study to analyze the functional results following elective laparoscopic sigmoidectomy for computed tomography (CT)-proven diagnosis of acute diverticulitis and review the literature. Forty-three of 45 available patients (96%) who had laparoscopic sigmoidectomy for CT-proven acute diverticulitis answered, after a mean time of 40 months, a questionnaire exploring new abdominal symptoms, bowel function, and the patient’s own judgement of the surgical outcome. Surgical technique aimed at removing all the sigmoid by taking down the splenic flexure and do a colorectal anastomosis. Four patients (9%) complained of new abdominal pain. Bowel function was reported as better for 24 patients (56%), unchanged for 16 patients (37%), and worse for 3 (7%). Twenty patients (47%) considered their final result as excellent to good, 17 patients (40%) as satisfying, and 6 patients (13%) as mediocre. Male gender, absence of preoperative history compatible with an irritable bowel syndrome, length of resected sigmoid and residual acute inflammation on histology are statistically predictive of a better postoperative degree of satisfaction. After elective laparoscopic sigmoidectomy for CT-proven diverticulitis, a great majority of patients are very satisfied with their postoperative general comfort.  相似文献   
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BACKGROUND: Basal cell carcinoma (BCC) is the most common type of skin cancer. One of the main problems with BCC is the risk of local recurrence of the tumor after treatment. This is mainly due to its irregular outgrowths, which cannot be detected clinically. OBJECTIVE: To better understand the tumor morphology and growth pattern of BCC, we tried to develop a method that provides a precise three-dimensional model of the tumor. METHODS: Because Mohs surgery provides the best overview of the tumor and the tumor margins (both lateral and in depth), the reconstruction was based on slides from Mohs surgery. After digitization and processing of the slides, the tumor was then surrounded by a Mohs surgeon on a computer screen. These selections (lines) were used for a three-dimensional reconstruction of the tumor using MedSurf3D software. RESULTS: This method allows three-dimensional reconstruction of any given BCC. The MedSurf3D software enables visualization of a three-dimensional model of the tissue, which is removed during the surgical procedure. CONCLUSIONS: Three-dimensional reconstruction is a fascinating tool that might improve our understanding of the behavior, growth pattern, and tumor morphology of BCCs. This technique might also be useful in other fields of cutaneous oncology, such as the calculation of the tumor volume of melanomas.  相似文献   
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