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Normative adontometric data are presented on a sample of 100 adult Cercopithecus aethiops(51 male, 49 female). When correlation effects among the teeth were held constant through multivariate canonical analyses,
contributions of individual tooth loci to the male-female distance were found to be similar to those isolated by univariate
means. The present study fails to support Garn’s field theory of sex dimorphism. When these patterns of sexual dimorphism
were contrasted with those of three other conspecific groups, the anterior teeth were found to show greater intrapopulation
variation than the posterior teeth. This, together with the finding that Penrose’s shape distances between the groups were
greater for anterior than postcanine teeth, provides evidence in support of Suolé’s hypothesis. The latter suggests, inter
alia, that high coefficients of variation indicate a proportionately higher environmental than hereditary contribution to
phenotypic variation. Negative correlations between tooth size and coefficients of variation suggest that tooth-size variability
is related to size rather than occlusal complexity. 相似文献
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Normative odontometric data are presented on a sample of 66 adult thick-tailed bushbabies Otolemur crassicaudatus(34 male, 32 female). This species is characterized by low levels of sexual dimorphism, with univariate differences centered
on the canines and the maxillary third molar. Multivariate canonical analysis isolates a third discriminator, the maxillary
second molar. Stepwise discriminant analyses, performed after jackknifing, indicate high percentages of correct classification
(males, 79.8–81.8%;females, 81–85.2%). When variability profiles consisting of arrays of CVs are compared, males and females are found to share
similar patterns. Data for maxillary teeth offer support for Gingerich’s occlusal complexity model, while morphogenetic clusterings
within regressions of variability on tooth size conform to those previously reported in other species. These relationships
are lost in the mandibular dentition, suggesting an independence of upper from lower toothsize determination. 相似文献
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Localization, analysis and evolution of transposed human immunoglobulin V kappa genes 总被引:6,自引:0,他引:6
E L?tscher F J Zimmer T Klopstock K H Grzeschik R Jaenichen B Straubinger H G Zachau 《Gene》1988,69(2):215-223
The localization of V kappa gene regions to chromosome 2, on which the kappa locus is located, and to other chromosomes is described. The V kappa genes that have been transposed to other chromosomes are called orphons. The finding of two new V kappa genes on chromosome 22 is reported. A V kappa II gene of this region and two V kappa I genes of the Chr1 and the cos 118 regions were sequenced. The two V kappa I orphon sequences and two others that had been determined previously were 97.5% identical, indicating that they may have evolved from a common ancestor by amplification. A model of the evolution of the human V kappa orphons is discussed. 相似文献
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Rearrangement of a common cellular DNA domain on chromosome 4 in human primary liver tumors. 总被引:8,自引:2,他引:6
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C Pasquinelli F Garreau L Bougueleret E Cariani K H Grzeschik V Thiers O Croissant M Hadchouel P Tiollais C Brchot 《Journal of virology》1988,62(2):629-632
Hepatitis B virus (HBV) DNA integration has been shown to occur frequently in human hepatocellular carcinomas. We have investigated whether common cellular DNA domains might be rearranged, possibly by HBV integration, in human primary liver tumors. Unique cellular DNA sequences adjacent to an HBV integration site were isolated from a patient with hepatitis B surface antigen-positive hepatocellular carcinoma. These probes detected rearrangement of this cellular region of chromosomal DNA in 3 of 50 additional primary liver tumors studied. Of these three tumor samples, two contained HBV DNA, without an apparent link between the viral DNA and the rearranged allele; HBV DNA sequences were not detected in the third tumor sample. By use of a panel of somatic cell hybrids, these unique cellular DNA sequences were shown to be located on chromosome 4. Therefore, this region of chromosomal DNA might be implicated in the formation of different tumors at one step of liver cell transformation, possibly related to HBV integration. 相似文献
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A colostral protein that induces the growth and differentiation of resting B lymphocytes 总被引:5,自引:0,他引:5
We describe the first protein of mammalian origin that induces the growth and differentiation of resting B lymphocytes. A proline-rich protein has been isolated from sheep colostrum. A purified proline-rich protein preparation (PRPP) induced resting mouse B cells into and supported their progression through the cell cycle at frequencies comparable with those seen for LPS. Differentiation of resting B cells to plaque formation was also supported as efficiently by PRPP as it was by LPS. However, PRPP was distinct from LPS in that it supported the growth and differentiation of resting B cells derived from either C3H/Tif or C3H/HeJ mice. Splenocytes from neonatal mice responded robustly to PRPP with the growth and differentiation of contained B cells to plaque formation. Unlike LPS, PRPP did not induce detectable Ig isotype switching. 相似文献
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Jacques Simard Dominique Bérubé Märten Sandberg Karl-Heinz Grzeschik Richard Gagné Vidar Hansson Tore Jahnsen 《Human genetics》1992,88(6):653-657
Summary A cDNA for the human catalytic subunit (C) of cAMP-dependent protein kinase (PKA) has been cloned from a testis cDNA library. In the present study, we have determined the chromosomal localization of this gene using a cDNA for C as a probe. Southern blot analysis of genomic DNA from human/mouse cell hybrids revealed that the presence or absence of a 20-kbXbaI fragment, which hybridized with the C probe, was concordant with the presence of human chromosome 1.In situ hybridization to metaphase chromosome confirmed the somatic cell hybrid data and regionally mapped the C gene of PKA to the p36 band on chromosome 1. 相似文献