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931.
P. Marion Handford 《Journal of applied microbiology》1974,37(4):559-570
S ummary . This paper describes the development and use of a selective diagnostic medium for the detection and enumeration of Clostridium perfringens in foods. The medium gives higher counts of Cl. perfringens and fewer false positives than existing media. 相似文献
932.
933.
934.
Morphogenesis and Homology in Arthropod Limbs 总被引:1,自引:0,他引:1
Arthropods exhibit highly diverse limb morphologies rangingfrom unbranched walking legs to multibranched swimming paddles.Understanding morphogenesis in structurally diverse limbs canbe useful for ascertaining homologies between limbs. Structurallysimilar limbs have been produced by different evolutionary modificationsof morphogenesis in certain cases. Whereas it is easy to supportthe claim that whole arthropod limbs are homologous structures,I demonstrate that it is not always possible to draw well-foundedhomologies between parts of different limbs. This result isimportant with regard to general models of appendage developmentand evolution in arthropods because it clarifies contradictoryexplanations based exclusively on gene expression data. 相似文献
935.
936.
Genetic programming for development in Drosophila 总被引:2,自引:0,他引:2
937.
Transduction and Genetic Homology Between Pseudomonas Species putida and aeruginosa 总被引:4,自引:0,他引:4 下载免费PDF全文
Genetic crosses occur by transduction between the species Pseudomonas aeruginosa and P. putida. The frequency relative to intraspecific transfer is reduced and varies among markers, suggesting that these genomes contain discrete regions of homology and nonhomology. 相似文献
938.
939.
W. H. Trethowan 《BMJ (Clinical research ed.)》1970,4(5727):109-111
At Birmingham University since 1966 the major medical examinations began to be replaced by a process of continuous assessment. This is based on fairly frequent tests, usually at the end of each course, including short essay questions, multiple-choice questions, and tests of ability in wards and laboratory. At the end of the first final-year course 96 students underwent assessment. Of these 77 passed; 19 were referred for re-examination, of whom a further 12 passed subsequently. The scheme was found suitable by both teachers and external examiners. 相似文献
940.