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41.
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T P?usa P Górski H Frank-Piskorska M Kowalski J Kruszewski P Kuna M Kurek R Kurzawa W Silny E Zawisza 《Canadian Metallurgical Quarterly》1996,1(4):292-293
A review of isolates of Neisseria meningitidis and other laboratory evidence of meningococcal infection was carried out for the period 1990-1995. Thirty-three patients with evidence of meningococcal disease were identified over the six year period. Group B organisms were the most commonly identified, but an increase in Group C has occurred and is almost equal in number. Data from clinical, laboratory and public health sources should be centralized in a National Surveillance Centre. 相似文献
43.
Thanapalan Murugesan G. S. Venkat Rathnam S. Panduranga Rao P. Gangadhar Rao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,63(3):290-294
In the present study of gas–liquid contactors, mean residence/contact time was calculated from knowledge of superficial velocity and the gas phase hold-up, for various gas rates and impeller geometry and speeds, and compared with values obtained from RTD measurements. A new correlation, involving Flow Number, Froude Number, system geometry and the physical properties, is proposed. This uses the authors data and those available in literature. 相似文献
44.
Using the fear-potentiated startle paradigm in rats, 4 experiments examined whether the inhibitory effect of a feature is evident after its offset following serial feature-negative discrimination training (A+ and X-->A-). When startle probes were presented shortly after the offset of X on X-->A test trials, the inhibitory properties of X were observed immediately after its offset. Furthermore, trace reinforcement of X (X-->+), but not delay reinforcement (X+), disrupted the ability of X to inhibit fear-potentiated startle on X-->A trials. Trace conditioning to X was also retarded after A+ and X-->A- training. These results suggest that the inhibitory properties of the serially trained feature are present after its offset and raise the possibility that either temporal information regarding nonreinforcement or poststimulus attributes of X acquire inhibitory properties. 相似文献
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Douay M. Xie W.X. Taunay T. Bernage P. Niay P. Cordier P. Poumellec B. Dong L. Bayon J.F. Poignant H. Delevaque E. 《Lightwave Technology, Journal of》1997,15(8):1329-1342
A comprehensive survey of photosensitivity in silica glasses and optical fiber is reviewed. Recent work on understanding the mechanisms contributing to germanium or aluminum doped fiber photosensitivity is discussed within the framework of photoelastic densification models 相似文献
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To prevent post-transfusional hepatitis B and C, two epidemiologic studies were performed. The first, based on the frequencies distribution of hepatitis B virus serological markers versus sex and classes of age, has permitted the assessment of the profile of the infection in a population composed of 573 north vietnamese blood donors. There is no significant difference between men and women frequencies of HBs antigen (11.5%), anti-HBs antibody (70.2%) and anti-HBc antibody alone (3.8%), but a significant difference of no-marker frequencies: 7.8% and 17.9% in men and women respectively (X2 = 9.11; p = 0.010). The percentage of no-marker decreases when the mean age of each class increases. The second, using the increase of the serum alanine aminotransferase (ALAT) activity as an indirect marker of non-A, non-B hepatitis for determining in a population of more than 25,000 parisian blood donors, the percentage of donors eliminated. They are between 0.70 and 0.76 in women and 2.26 and 2.46 in men. These investigations can be applied to prevent the hepatitis B transmission in a population of 102 south vietnamese women in age to procreate or to determine the percentage of blood donors eliminated (3.12%) in a population of 2,950 Parisians composed in majority (50.9%) of new donors. The hemobiologist will have an important role to elaborate strategies for orientation of blood gifts with hepatitis B and C virus markers. 相似文献
49.
The three-dimensional structure of glutathione S-transferase from Arabidopsis thaliana has been solved at 2.2 A resolution (Reinemer et al., 1996). The enzyme forms a dimer of two identical subunits. The structure shows a new G-site architecture and a novel and unique dimer interface. Each monomer of the protein forms a separate G-site. Therefore, the requirements on the dimer interface are reduced. As a consequence, the interactions between the monomers are weaker and residues at the dimer interface are more variable. Thus, the dimer interface looses its relevance for a classification of plant glutathione S-transferases and the formation of heterodimers becomes even more difficult to predict. 相似文献
50.