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971.
972.
973.
Lumbar spine bone mineral density in a cross sectional study of healthy subjects increased by 0.012 and 0.016 g/cm2/year in boys and girls respectively between 5 and 11 years of age. These rates increased five-fold in girls and threefold in boys between the ages of 11 and 13 years as a result of the bone mineral content increasing more rapidly than the coronal area at this age. By the age of 11 years the girls had 66% of the coronal area, 61% of the bone mineral density, and 41% of the bone mineral content of subjects aged 18-23 years. The ratio (lumbar spine bone mineral content/body weight) was constant in boys aged 6-13 years, but there were significant variations in girls. Femoral neck bone mineral density in both sexes changed little between 6 and 11 years and at 11 years was 69% of the adult values. Subjects with osteogenesis imperfecta had a low bone mineral density and bone mineral content for their age and weight. The z score of bone mineral density at the femoral neck was significantly lower than at the lumbar spine. In patients with recurrent fractures a low bone mineral density may help in identifying those with osteogenesis imperfecta and assist in their subsequent management.  相似文献   
974.
975.
重庆某高校桶装饮用水及饮水机微生物污染检测情况分析   总被引:3,自引:1,他引:2  
目的 了解桶装饮用水及饮水机微生物污染状况,探讨其原因并提出处理措施。方法检测了25桶桶装饮用水及43台饮水机用水的细菌总数和霉菌。结果 桶装饮用水及饮水机用水的细菌总数和霉菌都有一定的超标。结论 造成桶装饮用水及饮水机用水水质微生物超标的原因包括生产厂家因素、用户因素、卫生部门监管力度、市场规范等等方面。  相似文献   
976.
The present study extends the area of research on stress in parents of autistic children. In this study we used the Questionnaire on Resources and Stress (Holroyd, 1987) to compare the stress profiles across mothers (a) who lived in different cultural and geographic environments; (b) who had children of different ages; and (c) who had children with different functioning levels. Results showed a characteristic profile that was highly consistent across each of these subgroups. Major differences from the normative data occurred on scales measuring stress associated with dependency and management, cognitive impairment, limits on family opportunity, and life-span care. Results suggest the importance of developing treatment programs aimed at reducing stress in specific areas in families with autistic children.Orchard Mental Health CenterThis research was supported by U.S. Department of Education, NIDRR Cooperative Agreement No. G0087C0234 (Koegel and Dunlap), by U.S. Public Health Service Research Grants MH28210 (Koegel) and MH39434 (Schreibman) from the National Institute of Mental Health, by Grant No. G008530082 from the U.S. Department of Education, Handicapped Children's Early Education Program (Dunlap), and by Fogarty Senior International Fellowship 1 FOB TWO 1374-01 (Schreibman) from the Fogarty International Center of the National Institutes of Health. The authors acknowledge the contributions of Prof. Dr. med. Hedwig Amorosa, and Dorle Staniczek, Soz. Pad. of the Max Planck Institute for Psychiatry, Munich, West Germany, and express particular appreciation to Prof. Dr. med. D. Ploog, Director of the Institute.  相似文献   
977.
Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.  相似文献   
978.
H J Lin  C L Perng  F Y Lee  C H Lee    S D Lee 《Gut》1994,35(10):1389-1393
Detailed characterisation of non-bleeding visible vessels in terms of colour, size evolution, and time of rebleeding is important in determining the natural history of these lesions. The colour and size of non-bleeding visible vessels were observed endoscopically every day for three days and then every other day until rebleeding or flattening of visible vessels occurred in 140 patients. Rebleeding happened in 61 (44%) patients. Of them, 59 (97%) rebled within 72 hours. Flattening of visible vessels happened in 79 (56%) patients and 77 of 79 (98%) had flattening of visible vessels within 72 hours. Rebleeding rate increased with increasing length of exposed vessels (r = 0.96, p < 0.001). Coffee ground fluid or blood retention in the stomach and ulcer size > or = 2.0 cm were independent predictors for rebleeding using multivariate analysis. It is suggested that patients with non-bleeding visible vessels and independent predictors for rebleeding may need early aggressive treatment.  相似文献   
979.
The electrophysiological data of 23 adult patients with Lambert-Eaton myasthenic syndrome (LEMS) have been reviewed. Lung carcinoma was disclosed in 17. In six cases with an EMG follow-up ranging between one and 17 years no carcinoma was detected. The results of repetitive nerve stimulation test (RNS) were not statistically different between the 2 groups. Low CMAP ulnar amplitude was present in all patients (mean: 1.7 mV). Decremental response at low rate of stimulation (3 Hz) was present in 17/20 (means: 30%). An abnormal incremental response at high rate of stimulation was present in all cases (mean: 826%). The authors emphasize the interest of a 50 Hz stimulation for 4 s. Increase of the 'F-wave' amplitude was noticed in some cases. Electrophysiological changes suggestive of an associated mild neuropathy were noticed in eight patients but H-reflex was present in 3/3 cases. SFEMG abnormalities were found in 6/6 cases. In one case, stimulated SFEMG showed more blockings and an increased jitter with low rate of stimulation. In one case the electrical pattern of RNS could be misinterpreted as myasthenia gravis in one tested muscle only. The author's results suggest that CMAP amplitude and RNS test could be used to appreciate the short-term improvement of LEMS with treatment and in some cases for the long-term follow-up.  相似文献   
980.
S C Lin  S MacLeod  J W Hardin 《Endocrinology》1992,130(1):257-262
Glucocorticoid regulation of expression of the protooncogene fos has been examined in AtT-20 cells at both the RNA and protein levels. When cells were incubated continuously in the presence of dexamethasone, an early (30 min) rise in the expression of fos mRNA was observed, which declined by 1 h, but rose again after 2 h of hormone treatment. Six hours after hormone treatment, fos mRNA levels had returned to control levels in spite of the continued presence of dexamethasone. Serum treatment resulted in a sustained increase in fos mRNA levels; however, the glucocorticoid and serum effects were additive. Dexamethasone and/or serum both increased the steady state levels of fos protein. Glucocorticoid treatment of AtT-20 cells results in complex changes in fos expression, but does not affect their viability or growth rate; these results suggest that fos may play a role in mediation or modulation of glucocorticoid effects other than growth.  相似文献   
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