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101.
Conjunctival swabs were taken from both eyes of 70 healthy domestic rabbits and cultured to determine the microbial population. Bacteria were recovered from 83 per cent of the specimens. DNase-negative Staphylococcus species (57 per cent) were the most commonly recovered organisms followed by Micrococcus species (25 per cent) and Bacillus species (19 per cent). Other organisms isolated included Stomatococcus species (8 per cent), Neisseria species (8 per cent), Pasteurella species (6 per cent), Corynebacterium species (6 per cent), Streptococcus species (6 per cent) and Moraxella species (4 per cent), and other bacteria were isolated less frequently. Statistical analysis showed that there appeared to be no significant difference between the bacterial isolation rates from different breeds of rabbit. Significantly more of the swabs taken from young rabbits yielded cultivable bacteria than did those taken from rabbits over 12 months of age.  相似文献   
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Interference between two freely expanding Bose-Einstein condensates has been observed. Two condensates separated by approximately 40 micrometers were created by evaporatively cooling sodium atoms in a double-well potential formed by magnetic and optical forces. High-contrast matter-wave interference fringes with a period of approximately 15 micrometers were observed after switching off the potential and letting the condensates expand for 40 milliseconds and overlap. This demonstrates that Bose condensed atoms are "laser-like"; that is, they are coherent and show long-range correlations. These results have direct implications for the atom laser and the Josephson effect for atoms.  相似文献   
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Genetic Diversity Based on AIIozyme Alleles of Chinese Cultivated Rice   总被引:1,自引:0,他引:1  
Genetic diversity was analyzed with 6 632 core rice cultivars selected from 60 282 Chinese rice accessions on the basis of 12 allozyme loci, Pgil, Pgi2, Amp1, Amp2, Amp3, Amp4, Sdhl, Adhl, Estl, Est2, Est5 and Est9, by starch gel electrophoresis. Among the materials examined, 52 alleles at 12 polymorphic loci were identified, which occupied 96.3% of 54 alleles found in cultivated germplasm of O. sativa L. The number of alleles per locus ranged from 2 to 7 with an average of 4.33. The gene diversity (He) each locus varied considerably from 0.017 for Amp4 to 0.583 for Est2 with an average gene diversity (Ht) 0.271, mid Shannon-Wiener index from 0.055 to 0.946 with an average of 0.468. The degree of polymorphism (DP) was in a range from 0.9 to 46.9% with an average of 21.4%. It was found that the genetic diversity in japonica (Keng) subspecies was lower in terms of allele's number, Ht and S-W index, being 91.8, 66.2 and 75.7% of indica (Hsien) one, respectively. Significant genetic differentiation between indica and japonica rice has been appeared in the loci Pgil, Amp2, Pgi2, and Est2, with higher average coefficient of genetic differentiation (Gst) 0.635, 0.626, 0.322 and 0.282, respectively. Except less allele number per locus (3.33) for modern cultivars, being 76.9% of landraces, the Ht and S-W index showed in similar between the modem cultivars and the landraces detected. In terms of allozyme, the rice cultivars in the Southwest Plateau and Central China have richer genetic diversity. The present study reveals again that Chinese cultivated rice germplasm has rich genetic diversity, showed by the allozyme allele variation.  相似文献   
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