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961.
962.
This report presents national estimates of the prevalence and incidence of selected health conditions and their work-related consequences among currently employed persons 18 years of age and over. The major health conditions presented include back pain; hand discomfort; dermatitis; eye, nose, and throat irritation; and work injuries. Also presented are estimates of the distribution of workers on selected physical activities and exposures at work. Data are presented by age, sex, race, ethnicity, education, and broad occupational category. 相似文献
963.
964.
965.
The responses of 35 inferior colliculus multiple units (MUs) to tone onset were measured in 10 freely moving rats before and after differential behavioral conditioning. MU response changes were found in the 16.8 msec after tone onset (includes 2 msec air travel time) after learning. Responses to CS+ onset increased in 12 of the 35 individual MUs, and in the group of MUs as a whole, after conditioning. The CS+--CS- difference increased in 17 of the 35 individual MUs, and in the group of MUs, after conditioning. The response differentiation was significant in the 3.6-6.4 msec interval after the tone reached the animal's ears, the time at which neuronal responses were first evident. Since the inferior colliculus increases were differentiated between CS+ and CS-, they could not be explained by sensitization caused by changed middle ear contractions or by alterations in orientation to the speakers. 相似文献
966.
Taurine, a naturally found beta-amino acid, is inert in rat renal cortex slices. Its active accumulation by slices is abolished by anaerobiosis, a strongly acidic media or the removal of Na+. Concentration-dependent uptake studies reveal more than one taurine carrier: the apparent Km value for uptake below 1.1 mM is 0.4 mM and the apparent Km value above 1.1 mM is 14.5 mM. Of all amino acids tested only beta-alanine, another beta-compound, inhibited uptake. The oxidizing agent diamide was used to lower the concentration of GSH in rat cortex slices. The ability to accumulate taurine by the low Km system was decreased in diamide-treated slices, but not by the high Km system. Diamide was found to greatly augment efflux of taurine taken up from lower concentrations but not from higher concentrations. GSH in the media prevented this diamide-induced inhibition of uptake and enhanced efflux at lower taurine concentrations. A possible mechanism of diamide inhibition of uptake is that intracellular GSH depletion leads to greatly enhanced efflux of taurine, thus preventing uptake. 相似文献
967.
968.
969.
Estrogenic properties of 3,9-dihydroxybenz[a]anthracene, a potential metabolite of benz[a]anthracene
SL Schneider V Alks CE Morreal DK Sinha TL Dao 《Canadian Metallurgical Quarterly》1976,57(6):1351-1354
The estrogen receptor binding properties of 3,9-dihydroxybenz[a]anthracene (3,9-diOHBA) were determined in uterine cytosol of immature Sprague-Dawley rats by competitive binding experiments with [3H]estradiol and sucrose density centrifugation. 3,9-DiOHBA inhibited estradiol binding to the 8S binding protein at a concentration (1.2 X 10(-5) M) approximately equal to that of nafoxidine-HCl (3 X 10(-5) M) required to inhibit estradiol-specific binding, and bioassay for estrogenic activity substantiated this finding. 相似文献
970.
DK James 《Canadian Metallurgical Quarterly》1977,1(6055):217-219
Eighty-one calls made by the obstetric flying squad in West Berkshire were assessed on the basis of a suggestion that patients would do as well, if not better, if they were brought straight to hospital by ambulance rather than await the arrival of the flying squad. Of the 81 calls, 36 were made to general-practitioner maternity units and 45 were made to patients' homes. In both groups, the flying squad service was considered to be still of great value. Though slightly slower than an emergency ambulance call, it represents a much safer method of transporting an obstetric patient in an emergency. 相似文献