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931.
Smith PH 《Endeavour》2000,24(1):13-21
In about 1400, northern European artists suddenly began to depict the natural and human world in a 'realistic' or 'naturalistic' manner. At about the same time, new ideas about how to describe nature realistically emerged among scholars investigating the natural world. Over the next two centuries, this new approach to nature (which eventually became known as 'science') and the belief that it could provide a realistic depiction of nature transformed human attitudes to nature and the material world. Artisans or craftspeople were central to this transformation and thus more important than is usually recognized in forming the new attitudes that characterized the Scientific Revolution. 相似文献
932.
Samir P. Patel Subhash D. Katewa Surendra S. Katyare 《Indian journal of clinical biochemistry : IJCB》2005,20(1):1-8
Effects of treatmentin vivo with the antimalarials:chloroquine (CQ), primaquine (PQ) and quinine(Q) on lysosomal enzymes and lysosomal membrane integrity
were examined. Treatment with the three antimalarials showed an apparent increase in the membrane stability. CQ treatment
resulted in increase in both the ‘free’ and ‘total’ activities of all the enzymes i.e. acid phosphatase, RNase II, DNase II
and cathepsin D. PQ treatment lowered the ‘free’ and ‘total’ activities of acid phosphatase and cathepsin D, but the DNase
II activities increased. Treatment with Q resulted in increased ‘free’ and ‘total’ activities of RNase II and DNase II. While
‘free’ activities of acid phosphatase and cathepsin D were low; the ‘total’ activities increased significantly. Our results
suggest that a generalized increase in free nucleases activities following prolonged treatment with antimalarials may lead
to cell damage and/or necrosis. 相似文献
933.
In this study the effect of thiazide diuretic compound on the protein and cholesterol contents in the testes of albino rats
as the experimental model. The drug thiazide was administered orally daily for 10,20 and 30 days at the dose of 100mg/kg body
weight. Total protein decrease in the testes of rats were evidenced may be due to the side effects of thiazide drug compound
which is linked with the hyponatremia and protein metabolism. An elevated level of cholesterol contents observed in thiazide
treated rats also revealed that the side effect of drug compound thiazide and also may be due to the stimulation of catecholamine
which is stimulated therefore, the biochemical estimation such as protein and cholesterol in the testes after the thiazide
treatment determined the effectiveness of diuretic drug compound would provide clinical evidences of their side effects. 相似文献
934.
Study on arsenic level in ground water of Delhi using hydride generator accessory coupled with atomic absorption spectrophotometer 总被引:1,自引:0,他引:1
Sanjeev Lalwani T. D. Dogra D. N. Bhardwaj R. K. Sharma O. P. Murty Aarti Vij 《Indian journal of clinical biochemistry : IJCB》2004,19(2):135-140
Surveillance of drinking water is essentially a health measure intended to protect the public from water borne diseases. Hydride
generator accessory coupled with atomic absorption spectrophotometer was used to analyze arsenic level in 49 ground water
samples collected from different areas of Delhi. Arsenic level in ground water samples was in the range of 0.0170 to 0.100
ppm (Mean-0.0431, Standard Deviation-0.0136, Std. error of Mean-0.00194) with minimum concentration at Raney Well No. 7 (0.0170
ppm) and maximum at Kotla Mubarak Pur (0.100 ppm). Arsenic containing sediments and percolation of chemicals into soil as
the result of dumping of garbage rich in chemicals into open landfills could be the possible source of arsenic in ground water
of Delhi. Extensive survey and continuous monitoring is required to be made to assess the magnitude of problem and earlier
intervention. 相似文献
935.
Animation in computer-based instruction 总被引:1,自引:0,他引:1
936.
The capacity of newborn infants to smooth-pursuit eye movements in single-target tracking and in optokinetic nystagmus to a moving striped field was examined utilizing DC electrooculography. Smooth-pursuit movements were observed in all infants who were alert during testing, but they occupied less than 15% of viewing time during single-target tracking. The velocity of smooth-pursuit segments in single-target tracking increased linearly to a target velocity of 19 degrees/sec and deteriorated rapidly at faster speeds. No smooth pursuit occurred above 32 degrees/sec in single-target tracking. By contrast, optokinetic nystagmus was observed at all field velocities to 40 degrees/sec, but the speed of the mean slow component increased linearly to 25 degrees/sec and diminished above that field velocity. Infant optokinetic nystagmus differed strikingly from that of adults in that tonic ocular deviation was in the direction of field movement rather than away from it. This feature of neonatal optokinetic nystagmus is consistent with deficient foveal function and suggests that the relatively poor smooth-pursuit performance of newborns may be related to foveal immaturity. 相似文献
937.
John P. Houston 《Research in higher education》1976,5(4):301-311
Multiple-choice examination answer copying was indexed by a comparison of the numbers of items answered incorrectly, and in the same way, as adjacent and distant classmates. In Experiment I, which involved a regular university examination, significant copying did occur, did not differ from front to rear of the lecture hall, and appeared primarily among individuals seated next to one another. Copying was not related to the order in which the examinations were returned. Number correct was related to turn-in order in a U-shaped fashion. No significant copying appeared in a second experiment, where test performance did not contribute to course grade. 相似文献
938.
939.
940.
Ye Zhou-heng Ning Ke Ander Bradley P. Sun Xue-jun 《Journal of Zhejiang University. Science. B》2020,21(8):593-602
Journal of Zhejiang University-SCIENCE B - Methane is the simplest hydrocarbon, consisting of one carbon atom and four hydrogen atoms. It is abundant in marsh gas, livestock rumination, and... 相似文献