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Chronicle

Aleksandr Nikolaevich Shepoval’nikov (On his 75th birthday)  相似文献   

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The article recollects a biography of Professor Stanis?aw Skowron, distinguished Polish embryologist, geneticist, and evolutionist, known particularly well to all those working in the field of regeneration. In 1953 Professor S. Skowron founded and became the first editor of FOLIA BIOLOGICA an international quarterly journal of biological research devoted mainly to experimental zoology. He is also remembered as an eminent lecturer and excellent teacher of many generations of physicians, pharmacists, and biologists. A comprehensive list of his publications has been assembled and printed for the first time.  相似文献   

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Six different mosses have been recognised in samples taken from the intestinal contents of the 5,200-year-old Iceman from the Eastern Alps. Four of the species are important in understanding the lifestyle of the man and/or bear on the events during the last few days of his life: Anomodon viticulosus, Hymenostylium recurvirostrum, Neckera complanata and Sphagnum imbricatum. The past and present chorology and habitats of the Hymenostylium are discussed in detail, as is the ethnobotany of the Sphagnum concerning both the Iceman and Kwäday Dän Ts’ìnchí, the first ancient glacier body from North America.  相似文献   

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Kolman A 《Tsitologiia》2010,52(10):888-90, inside back cover
Dr. Bj?rn Ekwall (1940-2000) was a prominent Swedish scientist--cell toxicologist, who made an outstanding contribution in the field of in vitro toxicology. In the early 80-ties Ekwall formulated so called basal cytotoxicity concept, which served as a basis for modern orientation in the field of cell toxicology: the use of tests on cells in culture for prediction of acute systemic toxicity in humans, instead of the use of tests on experimental animals. To be able to verify his theories, Ekwall organized and led the international toxicological project called MEIC: Multicentre Evaluation of In Vitro Cytotoxicity Programme (1989-1999). In this project, 50 selected chemicals were tested in 100 laboratories worldwide with more than 60 different in vitro tests (laboratories have chosen tests themselves). MEIC project was unique not only because its large scale, but, in particular, because, for the first time, the human peak blood concentrations after acute poisoning with chemicals were used as references, aiming to check predictability of the in vitro assays. The results of the MEIC project have clearly demonstrated a possibility to use in vitro tests for prediction of toxicity of chemicals in humans.  相似文献   

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Abstract Male body size can play an important role in the mating systems of anuran amphibians. We conducted labora- tory-based trials with cane toads Rhinella (Bufo) marina from an invasive population in the wet-dry tropics of northern Australia, to clarify the effects of a male's body size on his reproductive success and behavior (mate choice). Males were stimulated with a synthetic hormone to induce reproductive readiness. Larger body size enhanced a male toad's ability to displace a smaller rival from amplexus, apparently because of physical strength: more force was required to dislodge a larger than a smaller amplectant male. A male's body size also affected his mate-choice criteria. Males of all body sizes were as likely to attempt amplexus with another male as with a female of the same size, and preferred larger rather than smaller sexual targets. However, this size prefe- rence was stronger in larger males and hence, amplexus was size-assortative. This pattern broke down when males were given access to already-amplectant male-female pairs: males of all body sizes readily attempted amplexus with the pair, with no size discrimination. An amplectant pair provides a larger visual stimulus, and prolonged amplexus provides a strong cue for sex iden- tification (one of the individuals involved is almost certainly a female). Thus, a male cane toad's body size affects both his ability to defeat rivals in physical struggles over females, and the criteria he uses when selecting potential mates, but the impacts of that selectivity depend upon the context in which mating occurs  相似文献   

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