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实验猴繁殖率的高低直接影响实验猴养殖企业的经济效益。本文借鉴本中心多年实验猴繁育经验,总结了一套较为完备的提高实验猴繁殖率的措施,内容涵盖实验猴繁殖特性、种公猴选种、繁殖猴分群及梯度饲养、孕猴用药、母猴产后护理、仔猴补饲及断奶、繁殖猴饲料搭配等各方面。这些措施应用于实践后,实验猴繁殖率可保持在较高水平并逐年提高。我们认为这些措施可在其它实验猴养殖企业推广应用。 相似文献
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Abstract: X‐ray microtomography (XMT) was applied to three species of the extinct arachnid order Trigonotarbida, hosted in siderite nodules from the late Carboniferous British Middle Coal Measures. All three, Cryptomartus hindi ( Pocock, 1911 ), Cleptomartus plautus ( Petrunkevitch, 1949 ) and Maiocercus celticus ( Pocock, 1902 ), belong to the family Anthracomartidae. As well as providing interactive three‐dimensional visualisations of their likely appearance in life, XMT study has resolved new morphological detail, yielding key data about the likely stance and habitus of these early arachnids. Similarities in the form of the carapace, eyes and coxosternal region between anthracomartids and the Devonian genus Palaeocharinus Hirst, 1923 are highlighted. Analogies in limb disposition are drawn between anthracomartids and modern crab spiders (Araneae: Thomisidae), which exhibit sit‐and‐wait style predatory behaviour. Anthracomartids are relatively common fossils at many Coal Measures localities. Although they appear to exhibit limited morphological variation, numerous genera and species have been proposed in the literature, often distinguished from each other on rather trivial characters. From our reconstruction of well‐preserved examples, we have resolved a number of common features likely to be present in a typical anthracomartid. Comparisons to this model suggest that the characters on which many anthracomartid genera are distinguished may be artefacts of preservation. We hence treat Promygale Fri?, 1901 , Brachylycosa Fri?, 1904 , Perneria Fri?, 1904 , Coryphomartus Petrunkevitch, 1945 , Cryptomartus Petrunkevitch, 1945 , Pleomartus Petrunkevitch, 1945 , Cleptomartus Petrunkevitch, 1949 and Oomartus Petrunkevitch, 1953 as junior synonyms of the type genus of the family, Anthracomartus Karsch, 1882 . Only the genera Brachypyge Woodward, 1878 and Maiocercus Pocock, 1911 are additionally retained. Within Anthracomartus, Cleptomartus planus Petrunkevitch, 1949 , Cryptomartus meyeri Guthörl, 1964 , Cleptomartus hangardi Guthörl, 1965 and Cryptomartus rebskei Brauckmann, 1984 are treated as junior synonyms of A. hindi Pocock, 1911 (all syn. nov.). Cleptomartus plautus Petrunkevitch, 1949 and Anthracomartus denuiti Pruvost, 1922 are treated as junior synonyms of A. priesti Pocock, 1911 (both syn. nov.). 相似文献
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Two new species of euthycarcinoids (Arthropoda), Kottixerxes anglicus sp. nov. and Smithixerxes pustulosus sp. nov., are described from the Coal Measures of Westhoughton, Lancashire and Coseley, West Midlands (Westphalian A and B respectively). Both genera are previously known from Mazon Creek, USA (Westphalian D). An additional, enigmatic arthropod with possible euthycarcinoid affinities, Arthrogyrinus platyurus gen. et sp. nov., is described from Coseley. Hypotheses concerning the phylogenetic position of euthycarcinoids are critically reviewed. 相似文献
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提高碱性蛋白酶生产效益的措施 总被引:6,自引:0,他引:6
裘娟萍 《氨基酸和生物资源》1996,18(2):32-35
综述了提高碱性蛋白酶生产效益的可能途径:菌种的及时复壮,菌种的诱变选育,菌种的代谢调控选育,工艺条件的控制。 相似文献
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Tim Friede Meinhard Kieser Markus Neuhuser Herbert Büning 《Biometrical journal. Biometrische Zeitschrift》2003,45(3):292-310
Although linear rank statistics for the two‐sample problem are distribution free tests, their power depends on the distribution of the data. In the planning phase of an experiment, researchers are often uncertain about the shape of this distribution and so the choice of test statistic for the analysis and the determination of the required sample size are based on vague information. Adaptive designs with interim analysis can potentially overcome both problems. And in particular, adaptive tests based on a selector statistic are a solution to the first. We investigate whether adaptive tests can be usefully implemented in flexible two‐stage designs to gain power. In a simulation study, we compare several methods for choosing a test statistic for the second stage of an adaptive design based on interim data with the procedure that applies adaptive tests in both stages. We find that the latter is a sensible approach that leads to the best results in most situations considered here. The different methods are illustrated using a clinical trial example. 相似文献
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Summary The concepts of a super information source and ensemble averaging are used to estimate the amount of information stored in protein andt-RNA sequences. Specifically applied to cytochrome c and hemoglobins, information measures analogous to those found to be highly significant for DNA pair frequency data (D
2 vs.R) by Gatlin (1968) prove to be extremely highly correlated with organism complexity. Super source stability and the possible taxonomic utility of the extraordinary clusterings obtained are discussed. A restriction on the construction of ancestral sequences and a possible handle on homology are also detailed. 相似文献
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实验动物学是一门应用型课程,任课教员需要具备较好的理论知识以及较强的操作能力和良好的沟通应变能力。对青年教员制定详细的培养计划以及健全培养评价机制,逐步提升新教员的任教能力,是一项长期值得探索的课题。本教研室坚持以提高教员素质为根本,通过完善年轻教员培养计划、优化新老教员一对一"传帮带"机制、建立青年教员试讲和课堂督导机制、完善教员与学员沟通机制、鼓励学习现代化信息手段丰富教学形式、健全新教员授课质量评价制度等举措,有效提高了年轻教员的专业水平、任教能力,年轻教员教学活动不断创新,学员满意度进一步提高。通过以上努力,教研室形成了一支以中青年教员为主的实验动物学教学团队,有效保障了实验动物学的教学质量,为今后医学院校实验动物学教学改革奠定了基础。 相似文献
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M.M. Shoukri M.A. Chaudhary G.H. Mohamed 《Biometrical journal. Biometrische Zeitschrift》2003,45(1):20-33
Twin data are of interest to genetic epidemiologists for exploring the underlying genetic basis of disease development. When the outcome is binary, several indices of 2 × 2 association can be used to measure the degree of within twin similarity. All such measures share a common feature, in that they can be expressed as a monotonic increasing function of the within twin correlation. The sampling distributions of their estimates are influenced by the sample size, the correlation and the marginal distribution of the binary response. In this paper we use Monte‐Carlo simulations to estimate the empirical coverage probabilities and evaluate the adequacy of the classical normal confidence intervals on the population values of these measures. 相似文献