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1.
Ann Hum Biol ; 27(6): 587-605, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11110224

RESUMO

The geographical distribution of the principal form of a French surname and its close variants (in spelling or pronunciation) has been analysed based on the French births registers, respectively from 1891 to 1915 and from 1916 to 1940, and on telephone directories for 1975. The spatial analysis of the individuals with the principal form of the surname suggests the existence of a positive spatial autocorrelation and three major areas of concentration in central France, the Loire country and Northern France. Within these three main areas of concentration, in 1975 most of the telephone subscribers with the principal surname are listed in rural communes with fewer than 3000 inhabitants, suggesting that the geographical pattern is not recent. Moreover, between the end of the 19th century and 1975 this pattern remains fairly constant. The geographical distribution of the holders of a 'variant' form of the surname shows the existence of a positive correlation between the absolute frequency of the principal surname and that of the variants, but only one area of concentration appears in Loire country. By analogy with the theory of centres of origin in genetics and linguistics, it is suggested that this unique area of concentration could be the region in which the surname originated. If that hypothesis proves to be correct, two main consequences follow: large migration movements occurred before the general rural exodus of the last century, and there has been no major, recent admixture of populations.


Assuntos
Nomes , Diretórios como Assunto , França , Geografia , Modelos Teóricos , Sistema de Registros , População Rural , Telefone , População Urbana
2.
C R Acad Sci III ; 323(6): 537-42, 2000 Jun.
Artigo em Francês | MEDLINE | ID: mdl-10923209

RESUMO

Thanks to a sampling of juvenile oysters with different growth rates (slow, medium and fast), a subtle biometrical study of their shell evolution is described distinguishing the two valves. We conclude that all the phenomena are dominated by the early establishment of a directional asymmetry, which rapidly becomes so large that we should consider dissymmetry. The clearest relationship is revealed to be that between the weakness of the growth rate and the degree of the relative dissymetry between the weights of the valves. This result is to be compared with the highly debated relationship between the asymmetry and the growth rate. The existence and interpretation of both of these phenomena have led to many publications.


Assuntos
Ostreidae/anatomia & histologia , Ostreidae/crescimento & desenvolvimento , Animais , Biometria , Tamanho do Órgão
3.
Proc Biol Sci ; 267(1447): 1021-5, 2000 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-10874752

RESUMO

A long-standing puzzle in gerontology is the sex dependence of human longevity and its inheritance. We have analysed the sex-linked pattern of inheritance of longevity from 643 nuclear families on the historical population register of a French valley. We have focused on mean conditional life expectancy at a minimum age of 50 years, thus, in the present study, longevity refers to late or post-reproductive survival. A comparison of parents' and offspring's longevity has shown the existence of a heritable component of late survival in this population. We have found that the heritable component was substantially larger for daughters compared to sons. Moreover, this result appeared to be specific to late survival, that is, when only post-reproductive mortality for parental and offspring generations is taken into account. The stronger resemblance of parents to their daughters was no longer observed when considering younger ages at death for the offspring. This observation explains the hitherto unaccountable diversity of data in previous studies.


Assuntos
Longevidade/genética , Feminino , França , Ligação Genética , Humanos , Masculino , Vigilância da População
4.
C R Acad Sci III ; 303(17): 709-12, 1986.
Artigo em Francês | MEDLINE | ID: mdl-3101986

RESUMO

Information on the size of populations of domestic cats from 42 countries allow us to estimate the total number of cats in the world: 400 millions. Methods and results are discussed.


Assuntos
Gatos , Animais , Animais Domésticos , População
6.
Biochimie ; 61(2): 137-45, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-465566

RESUMO

The main elements of reproduction are exposed with emphasis on its preparation during the larval stage. The system oocyte-nurse cells-follicular cells is described and the principal features of egg morphogenesis are indicated. Two types of problems are concentrated on : 1) sequential determination of growth and evolution of the follicle in the ovarian tube, 2) morphological and biochemical aspects of chorion formation. Variation in the functioning of the oocyte's morphogenetic system is explored with discussion of the role of larval alimentation, temperature, hormonal environment and genetic factors.


Assuntos
Bombyx/embriologia , Oócitos/crescimento & desenvolvimento , Óvulo/crescimento & desenvolvimento , Ração Animal , Animais , Bombyx/genética , Córion/anatomia & histologia , Córion/metabolismo , Feminino , Hormônios Esteroides Gonadais , Larva/citologia , Morfogênese , Oogênese , Folículo Ovariano/citologia , Reprodução , Temperatura
7.
Biomedicine ; 27(9-10): 362-4, 1977 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-606314

RESUMO

Erythrocyte G-6PD activity in 69 heterozygotes has a log-normal distribution, a fact which cannot be solely attributed to random X chromosome inactivation. Others factors - genetic and individual - are suggested by intrafamilial clusting and post-natal variability of phenotype.


Assuntos
Eritrócitos/enzimologia , Deficiência de Glucosefosfato Desidrogenase/genética , Feminino , Heterozigoto , Humanos , Recém-Nascido , Fenótipo
8.
J Embryol Exp Morphol ; 36(1): 13-8, 1976 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-988107

RESUMO

Ovarian follicle development, which accompanies morphogenesis of the silkworm egg has three distinct phases: spheric, ellipsoidal and flattened-ellipsoid. Transitions between phases are rapid and form-stability (characterized by length/width ratio) is preserved from the beginning of the ellipsoidal phase. The geometric stability of the follicle-oocyte-ovariole system, the polarity of the egg and the determinism in form changes reveal strikingly coordinated spatial and temporal organization.


Assuntos
Bombyx/embriologia , Oogênese , Animais , Feminino , Morfogênese , Oócitos/citologia , Folículo Ovariano/anatomia & histologia
9.
C R Acad Hebd Seances Acad Sci D ; 282(13): 1313-6, 1976 Mar 29.
Artigo em Francês | MEDLINE | ID: mdl-819175

RESUMO

The silkworm egg becomes bigger and more elongated as nymph growth temperature is increased. These effects vary with the egg's rank in the ovariole and are a morphological reflection of the existence of a gradient along the ovariole.


Assuntos
Oócitos/citologia , Óvulo/citologia , Temperatura , Animais , Bombyx/citologia , Diferenciação Celular , Feminino , Ovário/citologia
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