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101.
The energy costs of various domestic and agricultural activities were measured by indirect calorimetry in 56 women, 16–49 years old, from a small rural village. Mean energy expenditures (kcal/kg/min) were 0.021–0.035 for fourteen activities (“light occupations”), 0.038–0.064 for thirteen (“moderately active” occupations) and 0.072–0.089 for four (“very active” occupations). There were no differences per kg of weight between pregnant, lactating and non-pregnant, non-lactating women. The results were compared with other studies and weighted averages were calculated. The values reported can be used in combination with measurements of time to estimate energy expenditure in time-motion studies.  相似文献   
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The dual purpose of this study was, to evaluate the fracture rate of Ni-Ti rotary instruments when following a manual glide path and using stainless steel hand files before carrying out instrumentation by means of rotary files and, to compare the results in this study with those obtained in two previous analyses, in which the glide path technique was not used. A total of 208 canals obtained from a pool of freshly extracted human mandibular and maxillary molars was divided into three groups corresponding to; K3, ProFile and ProTaper. The coronal 2/3 of each tooth were used. In all three groups the apical portion of the samples was prepared with size 10-20 stainless steel K-type hand files. The apical stops were prepared using K3, ProFile and ProTaper rotary instruments. Logistic regression model analysis indicated that breakage was significantly associated with the angle of curvature of the canal (OR = 1.078; 95% CI = 1.032-1.12; p = 0.001), and with the number of clinical uses (files used more than eight times broke more frequently that those used 1 or 2 times; OR: 22.686; 95% CI: 2.6-191.3; p = 0.004). The breakage rate obtained in the present study is significantly lower than in our previous studies, in which the angle of curvature was also greater than 30 degrees and rotational speed a constant 350 rpm, but in which the canals were not first prepared with hand files (25/205 = 12% versus 16/61 = 26%, p = 0.007). Based on the results of this study, we recommend the use of stainless steel hand files to prepare the apical 1/3 of curved canals before introducing rotary files.  相似文献   
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Despite being considered a high risk procedure, renal transplantation has been recognized for more than 20 years as the best therapeutic option for children with end-stage renal disease since it is superior than any available dialytic procedure in improving the neuropsychological development and the quality of life. Today pediatric patients have similar graft survival than adults, and 10 year-old children or less have better outcome than any other age group. These remarking results are due to the development of specialized pediatric transplant centers and research programs, improvement in the selection and preparation of donors and recipients, refinement of the surgical technique and the use of new immunossupressive drugs.  相似文献   
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Clerodane diterpenoids from Salvia splendens   总被引:1,自引:0,他引:1  
Four new clerodane diterpenoids, salvisplendins A-D (1-4), have been isolated from an acetone extract of the flowers of Salvia splendens, together with an artifact (5), arising from salvisplendin D (4) by addition of diazomethane, and the already known clerodane olearin (6). The structures of the new compounds (1-5) were established mainly by 1D and 2D NMR spectroscopic studies and, in the case of salvisplendin A (1), by chemical correlation with splenolide B (7). Complete 1H and 13C NMR assignments for olearin (6), not published hitherto, are also reported.  相似文献   
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