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Clarke J 《Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences》2007,38(2):340-357
Three scientific societies devoted to the study of reproduction were established in Britain, France and USA in the middle of the twentieth century by clinical, veterinary and agricultural scientists. The principal motivation for their establishment had been the study of sterility and fertility of people and livestock. There was also a wider perspective embracing other biologists interested in reproduction more generally. Knowledge disseminated through the societies' scientific meetings and publications would bear upon human and animal population problems as well as basic reproductive physiology and its applications. New journals dealing with reproductive physiology, having worldwide appeal, were established in Britain and USA. The financial resources of at least one of the societies and its journal are directed towards charitable functions, including financial support for travel to scientific meetings, for visits to particular laboratories, and for research in the short term, including that of undergraduates. Perhaps the example of the British society has given rise to others having a more specialised focus, as well as to the formation of the European Society for the Study of Human Reproduction and Embryology. 相似文献
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The German Society of Parasitology (Deutsche Gesellschaft für Parasitologie) was founded in 1960 and its 21st biannual meeting took place in Würzburg, Germany, from March 17 to 20, 2004. Whereas interim meetings that are being held every other year focus on specific topics of parasitology, such as the symposia on "Life in Vacuoles" in 2003 and on "Immunomodulation by Parasites" in 2001, the general biannual meetings cover a wide range of topics. This year's meeting at the University of Würzburg was organised by Klaus Brehm and Matthias Frosch (both at the Institute of Hygiene) and Heidrun Moll (Institute for Molecular Biology of Infectious Diseases). It was attended by more than 500 scientists from 16 countries who presented 181 research projects dealing with the topics defence mechanisms and immunology, genomics and proteomics, epidemiology, cell biology and biochemistry, chemotherapy and vaccines, parasite classification and morphology, vectors, intermediate hosts, and veterinary parasitology. In addition, six plenary lectures highlighted the subjects of comparative nematode genomics, cell biology, immunology, and parasite eradication programmes. 相似文献
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The behaviour of some organic micropollutants in the abiotic compartments water, particulate matter and bottom sediments of the Scheldt estuary, S.W. Netherlands, was studied between 1986 and 1989. Special attention was given to two individual PolyChlorinated Biphenyl congeners (PCB 52 and PCB 153), two Polycyclic Aromatic Hydrocarbons (PAHs) fluoranthene and benzo(a)pyrene and γ-HCH. Dissolved PCBs and γ-HCH behave conservatively during estuarine mixing. The concentration of γ-HCH in the fresh-water is extremely high in spring compared to the other seasons. Dissolved fluoranthene does not behave conservatively. The concentration of dissolved fluoranthene in the freshwater endmember shows a seasonal dependence with highest concentrations in winter and lowest in summer. Benzo(a)pyrene could hardly be detected in the dissolved phase with the methods used. PCBs and PAHs in particulate matter and sediments behave essentially conservatively as a result of the mixing of riverine particulates with high, and marine particulates with low organic micropollutant contents. Particulate fluoranthene is removed at low salinities under (nearly) anoxic conditions probably by microbial degradation. The rivers Scheldt and Rupel appear to be the major sources for the compounds studied. However, in particular the organic micropollutant contents of the sediments indicate that important emissions along the estuary were or are still present. Measurements of individual PCBs and PAHs in the <63 μm fraction of a dated sediment core from a salt marsh in the eastern part of the Scheldt estuary show that the recent input of PCBs and PAHs into the estuaryis probably 2–3 times lower than the maximum input in the mid-1960s. The PCB profile shows postdepositional congener-selective mobilization caused by advective transport. The PAH assemblage is remarkably uniform in the sediment core. The PAH ratios indicate that combustion of coal is the main source of PAHs in the Scheldt estuary. 相似文献
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《European journal of protistology》2014,50(5):593-605
The morphology and infraciliature of two hypotrichous ciliates, Urosoma salmastra and U. karinae sinense nov. sspec., were investigated for populations collected from the surface of intertidal gravel in the Huguang Mangrove Forest, Zhanjiang, China and the upper 10 cm layer of soil in the Sangke Grass Land in the southern part of Gansu Province, China, respectively. Urosoma salmastra is characterized by its elongate-elliptical body with no tail-like structure; two macronuclear nodules; cortical granules colourless, less than 1 μm across, and arranged in short rows; adoral zone occupying 25% of body length in vivo; paroral conspicuously short and located in front of endoral. Urosoma karinae sinense nov. sspec. is characterized by its elongate-elliptical body with no tail; 2–4 macronuclear nodules; cortical granules colourless, less than 1 μm across, and arranged in short rows; adoral zone occupying 30% of body length in vivo; paroral shorter than, and located ahead of endoral. Phylogenetic analyses based on SSU rRNA gene sequence data suggest a close relationship between U. salmastra, U. karinae sinense nov. sspec. and Oxytricha granulifera within the Oxytrichinae assemblage. 相似文献
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James Tabery 《Journal of the history of biology》2008,41(4):717-761
This essay examines the origin(s) of genotype–environment interaction, or G × E. “Origin(s)” and not “the origin” because the thesis is that there were actually two distinct concepts of G × E at this beginning: a
biometric concept, or G × EB, and a developmental concept, or G × ED. R. A. Fisher, one of the founders of population genetics and the creator of the statistical analysis of variance, introduced
the biometric concept as he attempted to resolve one of the main problems in the biometric tradition of biology – partitioning
the relative contributions of nature and nurture responsible for variation in a population. Lancelot Hogben, an experimental
embryologist and also a statistician, introduced the developmental concept as he attempted to resolve one of the main problems
in the developmental tradition of biology – determining the role that developmental relationships between genotype and environment
played in the generation of variation. To argue for this thesis, I outline Fisher and Hogben’s separate routes to their respective
concepts of G × E; then these separate interpretations of G × E are drawn on to explicate a debate between Fisher and Hogben
over the importance of G × E, the first installment of a persistent controversy. Finally, Fisher’s G × EB and Hogben’s G × ED are traced beyond their own work into mid-20th century population and developmental genetics, and then into the infamous
IQ Controversy of the 1970s. 相似文献
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《Micron and Microscopica Acta》1989,20(2):159
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