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171.
AW Riley JW Finney ED Mellits B Starfield S Kidwell S Quaskey MF Cataldo L Filipp JP Shematek 《Canadian Metallurgical Quarterly》1993,31(9):767-783
Factors related to the amount of health care used by 5- to 11-year-old children in a health maintenance organization (HMO) were investigated using a comprehensive multivariate model that assessed the contribution of child health need, mental health, and social functioning; maternal mental health, social support and health care utilization; and family functioning and life events. Mothers reported on the 450 participating children. Health care visits for a two-year retrospective period were obtained from the computerized encounter system. Child health need and maternal patterns of health care use were powerful predictors of the overall amount of health care used, and these factors discriminated high users from low users of care. Family conflict was associated with a higher volume of care, while children's depressive symptoms and non-white race were related to lower use. Maternal social support, mental health, and life events were not predictive of use in either full multivariate model. Enabling factors were held relatively constant by participation of all families in a prepaid HMO. The multiple regression model explained 33% of the variance in use, slightly more than in previous studies of children's health care use. When included in a comprehensive analysis, child and family psychosocial characteristics help to explain children's health care use beyond what is possible using simple health and illness variables. The implications of these findings in the development of further research and to the practice of routine pediatric care are discussed. 相似文献
172.
The need for sensitive and comprehensive methods for determination of fumigant residues in foodstuffs is discussed. A multi-detection scheme for the evaluation of such residues is described, in which gas-liquid chromatography using three types of detector is used to analyse the contents of processed solvent extracts. Factors which affect the efficiency of recovery of such residues are discussed. These include the reactivity and volatility of residual components, the effect of water in solvent extraction, and the problems of multiphase extraction. The performance and specificity of the chosen system are considered in relation to other possible methods. Results are given showing the recovery of a range of 20 compounds as volatile fumigant residues in cereals and other foodstuffs, with sensitivities generally better than 0.1 ppm. The extension of the analytical scheme to include other compounds is indicated. 相似文献
173.
Bone marrow from mature goats and sheep was cultured in plasma clots, and three erythropoietin (ESF)-dependent responses-growth (colony formation), differentiation (globin production), and initiation of hemoglobin C (alpha2beta2C) synthesis--were quantitated. ESF concentrations below 0.01 U/ml supported colony growth and adult hemoglobin production in cultures of goat marrow, while maximal hemoglobin C synthesis (70%), as measured between 72 and 96 h in culture, required a 100-fold higher ESF concentration. Sheep marrow was cultured in a medium enriched to enhance growth and to permit complete maturation of colonies. These colonies active in hemoglobin synthesis between 24 and 96 h produced mainly adult hemoglobin, and only between 96 and 120 h did sheep colonies develop which produced mainly hemoglobin C (up to 70%). A similar heterogeneity may exist among goat colonies. Thus, when goat bone marrow was fractionated by unit gravity sedimentation, more hemoglobin C synthesis was observed in colonies derived from cells of intermediate sedimentation velocity than in colonies derived from the most rapidly sedimenting cells. Brief exposure of sheep (in vivo) and goat (in vitro) bone marrow to a high ESF concentration committed precursor cells to the generation of colonies which, even at low ESF concentration, produced hemoglobin C. Committment to hemoglobin phenotype appears to be an early and probably irreversible event in the development of an erythroid cell. 相似文献
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177.
Methods for screening and for confirming residues of lincomycin in animal tissues, both sensitive to 0.1 ppm, are described. In the screening technique, residues are extracted, cleaned up by solvent partition, and detected by microbiological plate assay. In the confirmatory technique, residues are cleaned up on an unfunctionalized macroreticular-type resin column, concentrated, chromatographed on thin layer plates, and detected by bioautography. This system was effective in identifying lincomycin in the presence of 20 other antibiotics and chemicals used in the animal health industry. 相似文献
178.
D Krasner KL Kennedy BS Rolstad AW Roma 《Canadian Metallurgical Quarterly》1993,39(8):66, 68-9, 72 passim
179.
OBJECTIVE: To investigate the ability of the Glasgow Coma Scale score to predict hospital mortality rate for adult medical-surgical intensive care unit (ICU) patients without trauma. DESIGN: A prospective cohort analysis of adult medical-surgical patients from a nationally representative sample of 40 U.S. hospitals. PATIENTS: 15,973 consecutive, nontraumatic ICU admissions and a comparison group of 687 head trauma admissions. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients' gender, age, treatment location before ICU admission, comorbidities, admission diagnosis, daily physiologic measurements, Glasgow Coma Scale score, Acute Physiology and Chronic Health Evaluation (APACHE III) score, subsequent hospital mortality rate, and unit-specific sedation practices were noted. Hospital mortality rates were stratified by the first ICU day Glasgow Coma Scale score for all admissions. The relationship between the Glasgow Coma Scale score and outcome for two high mortality medical diagnoses (post-cardiac arrest and sepsis) were also examined and compared to the relationship found in patients with head trauma. The Glasgow Coma Scale score on ICU admission had a highly significant (r2 = .922, p < .0001) but nonlinear relationship with subsequent outcome in ICU patients without trauma. Discrimination of patients into high- or low-risk prognostic groups was good, but discrimination in the intermediate levels (Glasgow Coma Scale score of 7 to 11) was reduced. This relationship varied within the operative and nonoperative groups, and also within different disease categories, various age groups, and certain ranges of the Glasgow Coma Scale score. A reduced initial Glasgow Coma Scale score associated with sepsis was a combination of factors associated with a higher mortality rate than that found in patients with head trauma. The proportion of patients who could not be assigned a Glasgow Coma Scale score because of sedation/paralysis varied widely across ICUs. The overall predictive capability of the APACHE III Prognostic Scoring System was improved by incorporating the Glasgow Coma Scale score. CONCLUSIONS: We demonstrated the prognostic importance of admission levels of consciousness as measured by the Glasgow Coma Scale score on ICU and hospital mortality rates. We concluded that the Glasgow Coma Scale score may be used to stratify and predict mortality risk in general intensive care patients, but lack of sensitivity in the intermediate range of Glasgow Coma Scale Score should be noted. Ideally, the Glasgow Coma Scale score should also be applied in the context of other physiologic information and the patient's specific diagnosis. Variation in the use of sedatives in different ICUs means that imputing or substituting a value other than normal for an unobtainable Glasgow Coma Scale score may introduce a substantial treatment bias into subsequent outcome predictions. 相似文献
180.
Primary and metastatic malignant fibrous histiocytoma of the alimentary tract is uncommon, even though it is the most frequently diagnosed malignant soft tissue tumor in adults. In this report, we describe a case of malignant fibrous histiocytoma of the colon. 相似文献