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71.
Kay Teschke Susan M. Kennedy Andrew F. Olshan 《American journal of industrial medicine》1994,26(3):327-337
During an exposure monitoring study, 78 saw maintenance tradesmen were randomly assigned to be interviewed about their exposures using one of two questionnaire formats: open-ended and partly prompted questions about five categories of materials; and detailed prompting about 75 agents. The more open-ended questionnaire elicited fewer exposure responses overall, but more responses about agents not included on the detailed questionnaire. Composite materials and trade name products were more frequently cited as exposures than individual metals or compounds. Validity of responses was ascertained using air measurements (individual metals) or observations of the employees (composite materials). Sums of sensitivities and specificities were very low (near 1.0) for most of the metals for both types of questionnaire. For composite materials, validity improved substantially. Sensitivities with the partly prompted format (0.44–0.85) were always lower than with detailed prompting (0.80–1.00). Specificities were usually, but not always, higher with partial prompting (0.66–0.92) than with detailed prompting (0.18–0.86). Selection of questionnaire format for an epidemiologic study would depend on the likely prevalence of exposure in controls and the effects of trade-offs in sensitivity and specificity. 相似文献
72.
The confrontation with one's body appearance as recorded on a video might have an impact on the body experience of anorexia nervosa patients. Such a video confrontation was applied to a group of 12 anorectic females. After the procedure, these patients rated their actual body (using Osgood's Semantic Differential) as thinner and more active; the control group of 12 female anorectics did not change their evaluations. The patients' evaluation of their ideal body image was not influenced. 相似文献
73.
74.
Satoshi Hisano Winnie Chan Kay Latta Richard J Krieg Jr. James CM Chan 《Clinical and experimental nephrology》1997,1(3):179-186
Growth retardation is a major complication in children with uremia. Protein restriction, calorie deficit, metabolic acidosis,
renal osteodystrophy, and endocrinologic disturbances contribute to the growth failure. The effect of these factors on growth
retardation can be attenuated in part by therapy with vitamin D metabolites, adequate nutrition, alkalization, and dialysis.
Linear growth in children with uremia is markedly retarded despite normal or increased levels of circulating serum growth
hormone. An increased growth hormone level in children with uremia is due to normal growth hormone secretion from the pituitary
gland and impaired growth hormone clearance in the kidney. However, the elevated growth hormone level does not lead to a commensurate
rise in serum insulin-like growth factor I (IGF-I); the serum IGF-I level is decreased or normal in relation to the degree
of renal failure. This discrepancy suggests growth hormone resistance in the liver in uremia. Recent molecular techniques
open a new era in studying the gene expression for growth hormone or IGF-I. There is no doubt today that growth hormone treatment
has the beneficial effect of growth promotion in children with uremia, which also suggests endogenous growth hormone resistance
in target organs or target cells in uremia. 相似文献
75.
76.
Neuron-specific enolase (NSE), a glycolytic enzyme enolase found in brain, was examined in the cerebrospinal fluid and serum of 30 patients with presumptive Alzheimer's disease (AD) and of 13 healthy controls and evaluated as a measure of neuronal functional activity associated with AD. The cerebrospinal fluid NSE levels of patients with AD were significantly reduced and serum NSE levels were significantly increased from controls. Cerebrospinal fluid NSE levels may be representative of central nervous system cell loss or a decrease in neuronal functional activity associated with AD. 相似文献
77.
Intravenous anaesthesia for cystoscopy: a comparison of propofol or methohexitone with alfentanil 总被引:2,自引:0,他引:2
Sixty out-patients undergoing cystoscopy were allocated randomly into two groups. No premedication was given. Induction of anaesthesia was preceded by intravenous alfentanil 7 micrograms kg-1 given over 20 s, followed by methohexitone 1.5-2 mg kg-1 or propofol 2 mg kg-1, given over 20 s. Anaesthesia was maintained by increments of alfentanil, methohexitone or propofol, given as required. 相似文献
78.
79.
The effect of environmental temperature on stroke occurrence in a subtropical climate was studied over a 1-year period by documenting the number of strokes (subdivided into cerebral infarct and intracerebral hemorrhage) admitted into a district hospital in Hong Kong at different temperatures. There was no significant correlation between the number of strokes (or its subtypes) per day per temperature category and the environmental minimum or maximum temperature. However, an association was present between the occurrence of cerebral infarcts and maximum temperature on the day of onset in elderly patients aged 70 years and above. Environmental temperature is not a strong risk factor for the occurrence of stroke in a subtropical climate. 相似文献
80.
We document the hemodynamic deterioration in two patients given very rapid intravenous infusions of 25% albumin. We developed an animal model to further elucidate the mechanism involved. Seven sheep were instrumented for the measurement of cardiac index (CI), pulmonary artery pressure (PAP), mean arterial pressure (MAP), left atrial pressure (LAP) and given 0.5 g/kg of Hyland brand 25% albumin over 5 min. Systemic vascular resistance index (SVRI), pulmonary vascular resistance index and left and right ventricular stroke work index were calculated. Equal volumes of normal saline were given to the same sheep as controls. Albumin significantly (p less than 0.05) increased MAP, PAP, LAP and SVRI, while CI decreased over the 3-10-min interval. Ibuprofen (14 mg/kg) intravenously administered 15 min prior to albumin, blunted all the above responses. This implicates a prostanoid as the possible mediator of these changes. 相似文献