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961.
In 1982 the levels of lead (Pb), cadmium (Cd), vanadium (V), copper (Cu), and selenium (Se) were determined in hair of 231 four- to five-year-old children. The objective was to explore the feasibility of using metal-in-hair levels in groups of children as an indicator of environmental pollution. The study was carried out in four areas, which were assumed to differ in ambient pollution by metals. A questionnaire on personal data, socioeconomic status, intake of beverages, and life-style was completed by the parents. The metal-in-hair levels covered a large range. The variables pertaining to location together with sex, presence of a garden, and drinking of coffee and/or tea explained 32% of the variance of Pb, 24% of the variance of Cd, and 21% of the variance of V. The total variance explained by all measured questionnaire items was at best 38%. The location was the most important factor. Cu and Se levels did not differ between the locations.  相似文献   
962.
The use of parenteral nutrition is becoming more widespread. The need for individualized parenteral nutrition solutions in pediatric patients makes the ordering and preparation of these solutions more complex and error-prone. A computer program is described which performs comprehensive management of parenteral nutrition by assisting in accurately ordering and preparing parenteral nutrition solutions. It also performs extensive error-checking and provides additional nutritional information. Data base management is also a feature which permits future large scale analysis of parenteral nutrition data for research purposes. This program, designed to run on a personal computer, is very comprehensive, yet flexible and user-friendly.  相似文献   
963.
We investigated the effects of imaging and display conditions on the detectability of low-contrast objects in digital subtraction angiographic (DSA) images. The test images were produced by superimposition of low-contrast objects on a uniform noisy background obtained with a DSA system. We employed 18-alternative forced-choice (18-AFC) experiments and predictions based on statistical decision theory to study the dependence of the threshold contrasts of the test objects on the object size, incident x-ray exposure, display window width, and display medium. The results indicated that the threshold contrast decreased with increasing object size, and that the detectability of an object of a given size increased with increasing incident x-ray exposure and decreasing width of the display window. We found that the signal-to-noise ratio (SNR) obtained from the perceived statistical decision theory model, which includes the observer's internal noise, can accurately predict the detectability of low-contrast objects in DSA images. The threshold SNR corresponding to 50% correct detection in the 18-AFC experiments had a constant value of 3.8, in agreement with results reported previously for screen-film systems. The theoretical model will be useful for prediction of the performance of a DSA system based on its physical characteristics, and for evaluation of the tradeoff between patient exposure and diagnostic accuracy for a given DSA unit.  相似文献   
964.
965.
Repeated testing attenuates conditioned place preference with cocaine   总被引:2,自引:2,他引:0  
Cocaine-treated rats acquired a preference for cocaine-associated contextual stimuli (CS) relative to saline-injected control rats. However, when animals were given repeated tests for conditioned place preference intermittent between conditioning trials, they displayed an attenuation in strength of conditioning. This attenuation was not due to pharmacologic tolerance (Experiment 1), but rather reflected a disruption in learning due to exposure to the CS alone (Experiment 2). Like other examples of classical conditioning, the strength of the conditioned response (CR) as assessed by the conditioned place preference model may be influenced by partial reinforcement.  相似文献   
966.
Forty patients suffering from asthmatic conditions, often accompanied by emphysema, were treated either with an extempore combination of salbutamol syrup plus 30-mg oxatomide tablets or with 30-mg oxatomide tablets alone for purposes of comparison. Greater efficacy was obtained with the combination, which produced positive results in terms of improved respiratory status, remission of clinical symptoms and reduced anti-asthma drug requirements in 90% of the cases treated, as against only 55% of satisfactory results obtained with oxatomide alone. The combination was very well tolerated with no incidence of adverse reactions, while the treatment with oxatomide alone, though on the whole well tolerated, gave rise to mild drowsiness in four cases.  相似文献   
967.
Western transfer and immunoenzymatic staining with affinity-purified monospecific antiserum was used to detect a 38-Kd protein that bound to native and denatured DNA cellulose. This protein has previously been shown to be a delayed early herpes simplex virus type-2 specific protein.  相似文献   
968.
The Brief Symptom Inventory (BSI), a 53-item psychiatric symptom checklist, was administered to 57 alcoholic inpatients on days 2, 10, 18 and 26 of their 28-day stay in an alcoholism rehabilitation unit at a Veterans Administration hospital. The results of the test show a steady decline in the patients' psychiatric symptomatology from week 1 to week 4 with the most dramatic improvement evidenced between weeks 1 and 2.  相似文献   
969.
An expert system for evaluation of X-ray diffraction patterns of urinary calculi is described and evaluated. The software was developed using the PERSONAL CONSULTANT expert system shell from Texas Instruments.  相似文献   
970.
The in vitro activities of beta-lactam antibiotics against Bacteroides fragilis and B. fragilis group isolates are presented. Clinical isolates from 1986 were compared with strains from 1979 to 1982. Imipenem, ticarcillin-clavulanic acid, and ceftizoxime were the most active agents. Cefotetan was equivalent to cefoxitin against B. fragilis but less active against B. fragilis group isolates. Enhancement of cefotaxime by its desacetyl metabolite was minimal.  相似文献   
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