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51.
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MN Janakiraman KD Watenpaugh PK Tomich KT Chong SR Turner RA Tommasi S Thaisrivongs JW Strohbach 《Canadian Metallurgical Quarterly》1998,8(10):1237-1242
Potent, non-peptidic, dihydropyrone sulfonamide HIV protease inhibitors have been previously described. Crystallographic analysis of dihydropyrone sulfonamide inhibitor/HIV protease complexes suggested incorporation of a second, C2 symmetry-related sulfonamide group. Selected bis-sulfonamide dihydropyrone analogues display high HIV protease inhibitory activity. 相似文献
53.
Fifty-six fourth-grade children participated in this study to assess three training procedures for relative effectiveness in acquiring fire emergency skills and attaining knowledge. The first training approach was behavioral, the second used animated graphics, and the third used still graphics. Each of the training groups was compared to a control group that received no treatment. Performance on dependent measures was assessed before and immediately after training. It was hypothesized that the behavioral and animated-graphics conditions would produce the greatest level of skill and knowledge acquisition. Results demonstrated a significantly higher level of fire emergency skill acquisition and knowledge attainment for both the behavioral and animated-graphics groups relative to the still-graphics group and the control group, which had no training. The value of using computer-mediated strategies for fire-safety skills training was demonstrated. 相似文献
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The lens epithelium of the human eye plays a crucial role in the pathogenesis of primary and secondary cataract. Sixty hematoxylin-eosinstained lens epithelia were examined using a light microscope. Cell parameters were compared to one another in the various age groups of patients, between patients with secondary cataract (radiation cataract, steroid cataract and traumatic cataract) and patients with senile cataract, and between male and female patients. The t-test was used for statistical comparison. The median cell density was 3116.5 cells/mm2. The median nucleus-plasma ratio was 1:2.74. Patients with secondary cataract had a larger medium cell and nucleus area as well as a higher nucleus-plasma ratio and a lower cell density than patients with senile cataract. A part from degenerative and proliferative cell changes we found various cell types. The age of patients and the cause of cataract correlate with morphometric changes of lens epithelium cells. However, there was no correlation between specific cytologic changes and causes of cataract. 相似文献
56.
Activation of auditory cortex during silent lipreading 总被引:1,自引:0,他引:1
GA Calvert ET Bullmore MJ Brammer R Campbell SC Williams PK McGuire PW Woodruff SD Iversen AS David 《Canadian Metallurgical Quarterly》1997,276(5312):593-596
Watching a speaker's lips during face-to-face conversation (lipreading) markedly improves speech perception, particularly in noisy conditions. With functional magnetic resonance imaging it was found that these linguistic visual cues are sufficient to activate auditory cortex in normal hearing individuals in the absence of auditory speech sounds. Two further experiments suggest that these auditory cortical areas are not engaged when an individual is viewing nonlinguistic facial movements but appear to be activated by silent meaningless speechlike movements (pseudospeech). This supports psycholinguistic evidence that seen speech influences the perception of heard speech at a prelexical stage. 相似文献
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Woodward William R.; Benassi Victor A.; Knoth Russell 《Canadian Metallurgical Quarterly》1993,48(1):53
Commemorates G. M. Haslerud, who died suddenly on April 10, 1990. In his doctoral dissertation (1934) he addressed free and prescribed maze patterns in rats, pointing to a lifetime interest in creative transfer. In 1972 he completed his magnum opus, Transfer, Memory, and Creativity: After-Learning as Perceptual Process, which reflects continuing conversations with his mentor, Robert Yerkes. Haslerud is remembered as a co-founder of the New Hampshire Psychological Association. (0 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
John A. Monro Winsome R. Harding Catherine E. Russell 《Journal of the science of food and agriculture》1985,36(10):1013-1018
Polysaccharide fractions were measured in coconuts at three stages of maturity, which corresponded to dietary usage in the Tokelau Islands of the South Pacific. Kernel was sequentially extracted with cold water (CW), hot water (HW) hot 0.5% ammonium oxalate (HOX), 1M H2 SO4 and 72% H2 SO4, and the monosaccharide compositions of the fractions determined. Total readily soluble fractions (CW+HW+HOX) were predominantly galactomannan, and decreased from 77% of the polysaccharide in the immature kernel to 8.8% of that in the mature kernel. Insoluble mannan increased during maturation to be the major polysaccharide component in mature kernel. This indicates that marked differences exist between the three stages of maturity examined, in the properties of their dietary fibre. The results suggest that in studies of diets in which coconut is a staple part, there is a need for careful definition of the coconut component with respect to maturity. Furthermore, they show the importance of using dietary fibre methods which are appropriate to the solubility characteristics of the indigestible polysaccharide. 相似文献
60.
A nuclease activity has been purified from the nuclei-kinetoplast fraction of Leishmania. This enzyme, termed endonuclease M (Endo M), is shown by electrophoresis in a denaturing polyacrylamide gel to be associated with a single polypeptide of molecular mass 52 kDa. Physical analysis of the enzyme indicates that it has a sedimentation coefficient S20,w of 4.5S, a Stoke's radius of 32.5 A, and a native molecular mass of 53 kDa. The final Mono Q purified Endo M possesses both DNase and RNase activities. It acts as an endonuclease by introducing random single-stranded nicks into the supercoiled DNA molecules, that often leads to its linearization due to nicking at the opposite strands, and subsequent degradation of the DNA with further incubation. Single-stranded DNA is twice preferred to double-stranded DNA as substrate. Single-stranded RNA is also degraded rapidly and is competitive as a substrate with single-stranded DNA. RNA:DNA hybrids, however, are largely resistant to the Endo M digestion. 相似文献