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排序方式: 共有637条查询结果,搜索用时 15 毫秒
561.
Prevalence of thinness and excessive fatness in a group of school children of the city of Cordoba, Argentina 总被引:1,自引:0,他引:1
F Agrelo B Lobo M Bazán L B Mas C Lozada G Jazán L Orellana 《Archivos latinoamericanos de nutrición》1988,38(1):69-80
Findings of a nutritional evaluation study, using triceps skinfold, are reported. The study was carried out in 1,615 school-children from 5 to 12 years, pertaining to the low socioeconomic status of the city of Córdoba, Argentina. Measurements were done during the years 1983 and 1984 by Center's examiners with a Lange caliper, according to international anthropometric methodology. Interintra observer technical error was found to be within tolerance limits reported by other authors. Local standards were used to determine the prevalence of thinness and excessive fatness, by comparing them to tricep skinfold of each child, and selecting those children where this parameter presented values less than or equal to 10th percentile and fatness greater than or equal to 90th percentile. Furthermore, comparison between median triceps skinfold of the examined group, the local standards and Frisancho's norms for US population was also made. Results revealed that: a) the prevalence of thinness (19.9%) was almost twice the percentage expected for a normal population; in contrast, occurrence of excessive fatness (6.4%) was found to be below the expected value; b) prevalence of thinness was not statistically associated to age nor sex; c) frequency of excessive fatness was significantly higher in the 8-11 year-old male group (8, 9%, p much less than 0.0005) and in the girls group (10.8%), P much less than 0.005) the prevalence of fatness in girls increased with age, and figures revealed that from eight years onwards this exceeded the expected percentage, and d) median triceps skinfold of the group under study was generally below local and foreign norms. It is concluded that potential or real nutrition problems as those mentioned above, may be grossly identified using the triceps skinfold as the single anthropometric indicator. 相似文献
562.
JH van Ree MA Roskrow AM Becher R McNall VA Valentine SM Jane JM Cunningham 《Canadian Metallurgical Quarterly》1997,39(3):393-395
Erythroid Krüppel-like factor (EKLF) is a trans-acting factor that binds specifically to the beta-globin promoter CACCC box. EKLF is essential for adult erythroid development in mice. We have cloned and sequenced a cDNA encoding the human homologue of this gene, which shares 69% identity with the mEKLF protein. The expression of hEKLF is restricted to fetal liver and adult bone marrow. The genomic locus of hEKLF was mapped to chromosomal band 19p13.12-p13.13, using fluorescence in situ hybridization. 相似文献
563.
A prospective surveillance programme for patients with longstanding (> = 8 years), extensive (> = splenic flexure) ulcerative colitis was undertaken between 1978 and 1990. It comprised annual colonoscopy with pancolonic biopsy. One hundred and sixty patients were entered into the programme and had 739 colonoscopies (4.6 colonoscopies per patient; 709 patient years follow up). Eight eight per cent of examinations reached the right colon. There was no procedure related death. One Dukes's A cancer was detected. Forty one patients (25%) defaulted. Of these 25 remain well; 13 are unaccounted for, and one died from colonic cancer. One patient had colectomy for medical reasons, and another died of carcinoma of the pancreas. Retrospectively an additional 16 eligible patients were identified who had not been recruited. Of these, 14 remain well, two are unaccounted for. None developed colonic cancer. Four patients refused colonoscopy. All remain well. Over the same period seven other cases of colonic cancer were found in association with ulcerative colitis, two in patients who had erroneously been diagnosed as having only proctitis and were therefore not entered into the programme, but were found at operation to have total colitis, one in a patient with colitis of seven years duration, and four patients who had previously attended the clinic but had been lost to follow up before 1978 and then had represented with new symptoms during the surveillance period. Thus, of the nine colitis related cancers diagnosed in this centre during the study period only one was detected by the surveillance programme. The results of this large study, a a review of published works, cast doubts on the effectiveness of colonoscopic surveillance programmes in detecting colorectal cancer in patients with ulcerative colitis. 相似文献
564.
The trend to larger grinding mills with the attendant increase in motor drive horsepower has affected the options for drive equipment. Also the development of large adjustable speed drives has created new possibilities for mill drives. Grinding mill torque characteristics, drive requirements, and torsional excitations of the various types of available drives will be briefly reviewed. 相似文献
565.
Hydrogenation of 473–573 K distillate derived from the product of catalytic hydrogenation of coal in the presence of hydrogen-donor solvent and ethyl alcohol and dimethyl-formamide extracts of the tar from low-temperature (fluidized-bed) coal carbonization have been investigated in the presence of rhodium complexes. The complexes used (293–393 K; 0.1–5 MPa) bpth in homogeneous and in immobilized forms are catalytically active in hydrogenation of those coal-derived liquids. However, the increase of H/C atomic ratio is low. The catalysts in the immobilized form have not been deactivated in several catalytic cycles following. 相似文献
566.
A Cahn Electrobalance has been used to determine directly and very accurately the carbon content of iron, iron-0.48 wt pct
molybdenum and iron-1.16 wt pct molybdenum specimens which were equilibrated with a series of methane-hydrogen gas mixtures
of constant composition. The equilibria investigated involved the austenite phases of the alloys at 783, 813 and 848‡C. The
experimental results permit direct calculation of the activities of carbon in the samples, relative to graphite as unity,
and of the enthalpy and entropy of solution of carbon. The results are compared with the experimental measurements of a number
of other investigators. The results are in excellent agreement with those of Smith and Schenck and Kaiser for the Fe-C system
at 800‡C, and indicate -H
C
/M
values of 9700 ± 500 cal/mole for pure Fe, 10,030 ± 500 cal/mole for an Fe-0.48 wt pct Mo alloy, and 10,150 ± 500 cal/mole
for an Fe-1.16 wt pct Mo alloy. The effect of molybdenum in austenite is to decrease the activity coefficient of carbon in
austenite. 相似文献
567.
Domingos C. Ferreira L. V. Prista R. M. Morgado J. M. Sousa Lobo 《Drug development and industrial pharmacy》1995,21(5):591-604
Sustained-release tablets containing oxazepam were prepared and dissolution profiles were investigated. The total dose of oxazepam is constituted of initial and maintenance dosage. A method for the preparation of hydrophilic matrix tablets is presented. The study of the dissolution rate of these preparations in artificial gastric (in the first two hours) and enteric juices (in the following ten hours) was experimented. No significant differences in oxazepam release rate were found between the formulations containing lactose, zinc sulfate, calcium sulfate or calcium phosphate added intragranularly to the maintenance dosage. The dissolutions studies of oxazepam preparations demonstrated differences in drug release properties depending on the content of extragranular croscarmellose sodium. 相似文献
568.
569.
Conflict resolution using logic programming 总被引:7,自引:0,他引:7
Chomicki J. Lobo J. Naqvi S. 《Knowledge and Data Engineering, IEEE Transactions on》2003,15(1):244-249
570.
A vector-valued impulsive control problem is considered whose dynamics, defined by a differential inclusion, are such that the vector fields associated with the singular term do not satisfy the so-called Frobenius condition. A concept of robust solution based on a new reparametrization procedure is adopted in order to derive necessary conditions of optimality. These conditions are obtained by taking a limit of those for an appropriate sequence of auxiliary “standard” optimal control problems approximating the original one. An example to illustrate the nature of the new optimality conditions is provided. 相似文献