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31.
S Honjo 《Journal of medical primatology》1985,14(2):75-89
The facilities and activities of the Japanese Primate Center at Tsukuba, Japan are described. The Center became partially functional in 1978 and was completed in 1979. The three main aims of the Primate Center are: to quarantine newly imported primate animals, to breed, and to study them. 相似文献
32.
Long bone growth is analyzed for 180 children from a Medieval population at Kulubnarti in Sudanese Nubia (550–1450 A.D.). A regional interpopulation comparison is made with growth data from Wadi Halfa in Lower Nubia, and an intrapopulation analysis is undertaken to assess diachronic changes in growth at Kulubnarti. Changes in growth patterns are interpreted in the context of mortality and morbidity profiles and relationships between the three variables are discussed. It is suggested that changes in the sociopolitical environment may have been responsible in part for altering levels of biological stress and impacting growth. 相似文献
33.
A multivariate t probability integral 总被引:2,自引:0,他引:2
34.
János Podani 《Plant Ecology》1989,83(1-2):111-128
The methodology of comparing the results of multivariate community studies (resemblance matrices, ordinations, hierarchical and nonhierarchical classifications) is reviewed from two viewpoints: basic strategy and measure employed. The basic strategy is determined by 7 choices concerning the type of results, consensus methods or resemblance measures, hypothesis testing or exploratory analysis, lack or presence of reference basis, data set congruence or algorithmic effects, number of factors responsible for differences among results, and the number of properties considered in the comparison. Included is a brief summary of methods applicable to vegetation studies. Examples from a grassland survey demonstrate the utility of comparisons in evaluating the effects of plot size, data type, standardization, taxonomic level and number of species on classifications and ordinations.Abbreviations OUC =
Operational Unit of Comparison
- PCA =
Principal Components Analysis
- PCoA =
Principal Coordinates Analysis
- SSA =
Incremental Sum of Squares Agglomeration 相似文献
35.
The larvae of the dipteran insect, Chironomus ramosus, found in Shillong, India, contain eleven (11) hemoglobin (Hb) components of which three are monomers (CI, CIV and CVI) and seven are dimers (CIII, CV, CVII, CVIII, CIX, CX and CXI), while one (CII) exists in both monomeric and dimeric states.Four monomeric components were isolated, purified and partially characterized. The N-terminal amino acids were determined and showed glycine for CI and leucine for the other components (CII, CIV and CVI).Three hemoglobin components were found to be present in all stages of larval development, except the first instar larvae. Some Hb components were synthesized in a particular instar, as revealed by electrophoretic appearance.Electrophoretic mobilities of seven components and N-terminal amino acid residues of two components of Hb were similar in both Chironomus ramosus and Chironomus thummi thummi. 相似文献
36.
We report the isolation and characterization of two new genomic loci corresponding to the mouse Dishevelled (Dvl) genes Dvl2 and Dvl3. The Dvl genes are homologs of the Drosophila dsh segment polarity gene, and are involved in the Wnt/wingless signal transduction pathway. Dvl2 and Dvl3 genomic clones were isolated from a mouse 129 strain λFIXII genomic library and have identical exon/intron organization to Dvll. All three Dishevelled genes span 15 exons and 14 introns and have a number of conserved splice junction sites. 相似文献
37.
Alexandra M. Birrell Annemarie Hennessy Adrian Gillin John Horvath David Tiller 《Journal of medical primatology》1996,25(4):287-293
Abstract: Baboons are widely used in biomedical research. Although it is widely held that Papio hamadryas breed well in captivity, each established colony has a different reproductive success often hypothesised to be due to husbandry practices. The National Baboon Colony in Australia is a unique colony that houses Papio hamadryas to mimic that structure seen in the wild. In this article; we have analysed their reproductive parameters and neonatal outcomes. The success of the colony husbandry practices was demonstrated by lack of maternal mortality, low foetal morbidity, and known maternal and paternal linage. 相似文献
38.
三种鱼类生长激素cDNA基因的结构比较研究 总被引:3,自引:0,他引:3
从厦门海区选取3种生长速度不同的鱼类,真鲈、高体Shi、褐菖You,由它们的脑下垂体中分别提取出总RNA,用逆转录PCR方法(RT-PCR)扩增出生长激素cDNA,克隆到pBluescript载体上的EcoRI位点,并分别测定了这3种鱼的成熟生长激素cRNA序列。将由这3种序列推导出的氨基酸序列同已知的8种不同科鱼类的生长激素氨基酸序列进行比较,分析它们序列的同源性,结果表明它们间的同源性与这些鱼 相似文献
39.
Summary Chickpea was micropropagated by axillary shoot proliferation (ASP) and modified single node culture (MSNC) methods. Maximum
propagule proliferation occurred on Murashige and Skoog (MS) medium enriched with 1–10 μM N6-benzyladenine and 0.01 μM α-naphthaleneacetic acid. The propagules were rooted on MS medium containing 1 μM 3-indolebutyric acid and B5 vitamins. Regenerated plants were fertile and phenotypically similar to control plants grown from seed. The MSNC method was
four times more efficient than the ASP method in terms of the number of plants produced per explant. 相似文献
40.
Joseph Cain 《Biology & philosophy》1994,9(3):387-427
Ernst Mayr's contributions to 20th century biology extend far beyond his defense of certain elements in evolutionary theory. At the center of mid-century efforts in American evolutionary studies to build large research communities, Mayr spearheaded campaigns to create a Society for the Study of Evolution and a dedicated journal,Evolution, in 1946. Begun to offset the prominence ofDrosophila biology and evolutionary genetics, these campaigns changed course repeatedly, as impediments appeared, tactics shifted, and compromises built a growing coalition of support. Preserved, however, were designs to balance the community and journal with careful equation of status and explicit partitioning of responsibilities within the working coalition. Choice terms such as cooperation and unity carried a strong political message. Mayr's editorship ofEvolution provides a superb example of these balancing efforts. The mid-century infrastructural activities described herein also represented aggressive attempts to leverage control across several layers of community. Leaders of these campaigns sought: (1) to promote evolutionary studies as a modernized research discipline and place it at the center of American biology, (2) to promote evolutionary studies within existing disciplines — e.g. systematics, genetics, and paleontology, (3) to foster certain research styles within evolutionary studies, and (4) to emphasize certain solutions to prominent research questions. Throughout, Mayr interjected his priorities, tactics and energy. 相似文献