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991.
Separation of Legionella pneumophila proteases and purification of a protease which produces lesions like those of Legionnaires' disease in guinea pig lung 总被引:11,自引:0,他引:11
Six discrete protease activities were recovered from the supernatant broth of Legionella pneumophila cultures by ion-exchange chromatography. One of these demonstrated in vitro activity against collagen, casein and gelatin. When administered into the lungs of guinea-pigs this protease elicited lesions which were pathologically similar to those seen in clinical and experimentally induced Legionnaires' disease. 相似文献
992.
993.
Myosin ATPase and succinic dehydrogenase activity and fast myosin (indirect immunochemical test) were assayed in m. soleus of guinea-pigs after the administration of T4 (200 micrograms/kg) to animals every day for 3 weeks. This was followed by the application of 10 mM colchicine solution to sciatic nerve for 6 min. Fast muscle fibers and the line of precipitation with antiserum to fast myosin were revealed in soleus muscle of experimental animals after the application of colchicine and T4 injection. 相似文献
994.
The infectivity and development of four populations of Meloidogyne hapla were compared, at three temperatures, on tomato and two varieties of cucumber. A population from Canada produced few root-galls on cucumber and, except at 24 C, no larvae developed into adult females and produced egg masses. In contrast, a population with 45 chromosomes from America produced many galls on cucumber and small proportions of larvae became females and produced egg masses at 20 and 24 C. At 18 C this population produced no egg masses on cucumber, but a population from Britain and one from America with 17 chromosomes produced more egg masses at this temperature than at 20 or 24 C. Dissection of the galls showed that on cucumber many larvae died or their growth and development was slowed. 相似文献
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996.
A. V. Mazaev 《Paleontological Journal》2006,40(4):391-403
Permian gastropods from the Kulogory Formation (Sakmarian) were studied based on the author’s material and the collection of Yakowlew (Central Research Geological Prospecting Museum (TsNIGR Museum), St. Petersburg). Lectotypes for Arribazona tschernyschewi (Yakowlew, 1899) and Microdoma kulogorae (Yakowlew, 1899) were designated. Six species are described; four of them are new and two are assigned to the new genera (Biarmeaspira verideclinata gen. et sp. nov., Globodoma yakowlewi gen. et sp. nov., Glabrocingulum (Glabrocingulum) stankovskyi sp. nov., and Euconospira? pinegensis sp. nov.). The high degree of polymorphism in the dominant species of uniform assemblages is probably the result of their development in “undersaturated” paleocommunities of closed lagoons with gradually increasing concentration of sulfate ions. 相似文献
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