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In a previous study, we showed that estimates of the BSE epidemic in France were censored by cattle mortality and by a lack of diagnosis. Indeed, we estimated that 51 300 cattle were infected by the BSE agent between 1987 and 1997, whereas only 103 clinical BSE cases were detected by the passive surveillance system up to June 2000. The question thus arises as to the part played by each form of censorship in this underestimation. Here, using an updated cattle survival distribution, we estimated that 44 800 cattle were infected by the BSE agent between 1987 and 1997, and that 7100 of them showed clinical signs of BSE up to June 2000, showing the low efficiency of the surveillance system. Moreover, between 2087 and 5980 'infectious' cattle, with clinical or preclinical BSE, entered the human food chain before July 1996, the date of the ban on specified bovine offal.  相似文献   

3.
Glutathione S-transferase class μ in French alcoholic cirrhotic patients   总被引:6,自引:1,他引:5  
Summary The lack of glutathione S-transferase (GST) was examined in 45 healthy French Caucasians and 45 alcoholic cirrhotic French Caucasians: microsamples of blood were taken and DNA amplified by the polymerase chain reaction. We have concluded that there is no relationship between this genotype and the development of alcoholic cirrhosis in these heavy consumers of ethanol.  相似文献   

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Dung beetles have widely been accepted as cost-effective indicator taxa for biodiversity assessment; thus, standard protocols have been created to examine their species richness and diversity in many habitats. However, the vast majority of studies adopt short-term sampling protocols; few studies have quantified sampling efficiency at longer time scales or tested the efficacy of species richness estimates. Here we present long- and short-term sampling data from two regions of French Guiana: the Nouragues Tropical Forest Research Station and Kaw Mountain. We examine species richness and diversity, and use these data to make suggestions for future biodiversity assessments of dung beetles using dung baited pitfall transects. Species richness estimates based on short-term samples strongly underestimate the actual species richness by approximately 40?%. Duration of trapping was found to be more important than the number of traps and length of transects; by setting a second transect (4-day sample period) in the same habitat of Nouragues, thereby increasing the sample duration, the number of species increased by 14?%.  相似文献   

7.

Background

Recently, a mutation was discovered in the DMRT3 gene that controls pacing in horses. The mutant allele A is fixed in the American Standardbred trotter breed, while in the French trotter breed, the frequency of the wild-type allele C is still 24%. This study aimed at measuring the effect of DMRT3 genotypes on the performance of French trotters and explaining why the polymorphism still occurs in this breed. Using a mixed animal model, genetic parameters and environmental effects on performance traits were estimated from data on 173 176 French trotter races. The effect of the DMRT3 gene was then estimated by the effect of genotype at the highly linked SNP BIEC2-620109 (C-C, A-T) for 630 horses. A selection scheme that included qualification and racing performances was modeled to (1) verify if the observed superiority of heterozygous CT horses at this SNP could be explained only by selection and (2) understand why allele C has not disappeared in French trotters.

Results

Heritability of racing performance traits was high for qualification test (0.56), moderate for annual earnings per finished race (0.26 to 0.31) and low for proportion of disqualified races (0.06 to 0.09). Genotype CC was always unfavorable compared to genotype TT for qualification: the probability to be qualified was 20% for CC vs. 48% for TT and earnings were -0.96 σy lower for CC than for TT. Genotype CT was also unfavorable for qualification (40%) and earnings at 3 years (-0.21 σy), but favorable for earnings at ages greater than 5 years: +0.41 σy (P = 7.10−4). Selection on qualification could not explain more than 19% of the difference between genotypes CC and CT in earnings at ages greater than 5 years. Only a scenario for which genotype CT has a favorable effect on the performance of horses older than 5 years could explain that the polymorphism at the DMRT3 gene still exists in the French trotter breed.

Conclusions

The use of mature horses in the French racing circuit can explain that the CA genotype is still present in the French trotter horses.  相似文献   

8.
John D. Mitchell 《Brittonia》1994,46(3):225-227
Botanical exploration of the vicinity of Saül, French Guiana, with the goal of producing a manual of the vascular plant flora, has yielded a new species ofSmilax. A diagnostic characteristic that differentiates this new species from all other species ofSmilax known from the Guianas and the Amazonian region is the admedial ramified branching pattern of the tertiary leaf veins.  相似文献   

9.
Objective: Our objective was to investigate whether people who use internal cues of satiation when eating a meal are likely to weigh less than people who instead rely on external cues. In addition to exploring the role that internal and external cues play in meal cessation, this study raises an overlooked explanation of the French paradox. Research Methods and Procedures: A demographically‐matched student sample of 133 Parisians and 145 Chicagoans completed a brief survey on meal cessation that asked the extent to which they agreed with statements associated with internal cessation cues and statements with external cessation cues. Their answers to these were compared across BMI levels and across countries. Results: Normal‐weight people indicated that they were more likely to be influenced by internal cues of meal cessation (p = 0.043), while overweight people indicated that they were more influenced by external cues (p = 0.005). Similarly, while the French were influenced by internal cues of meal cessation (p < 0.001), Americans were more influenced by external cues (p < 0.001). Discussion: This research revisits Schachter's externality hypothesis and suggests that one's over‐reliance on external cues may prove useful in offering a partial explanation of why BMI might vary across people and potentially across cultures. Relying on internal cues for meal cessation, rather than on external cues, may improve eating patterns over the long term.  相似文献   

10.
Conclusion The first part of this paper has shown that the development of regulatory genetics and the lactose operon model stemmed from laboratory cultures rooted in local traditions. A "physiological" culture may be recognized in the Pasteurian context. The institutional continuity provided the basis for a tenuous link between Pasteur, Lwoff, and Monod. My claim is that the "national" value of regulatory and physiological genetics is an artifact produced in the course of the legitimization process accompanying the institutionalisation of the discipline. In the 1960s, the lactose operon model was turned into a "flag-object," a symbol of the new culture. The work done by the Pasteurian group became therefore the most important, if not the only, exemplar of molecular biology in France.The second part o f the paper described the origins of general patterns that dominated the building of molecular biology in France. The study of the relationships between molecular biologists and biochemists or immunologists revealed the existence of alternatives to the development of operon research, or to the convergence with molecular biology. Both examples uncover specific paths leading to achievements that might be viewed as international trends: the expansion of RNA and translation studies, and the development of cellular immunology. They illustrate two possible patterns of linking local settings and disciplinary traditions: an oligopolistic situation where a few groups or one institution dominate an entire field, and the emergence of "collective" trends through collaboration networks or schools.  相似文献   

11.
A new species in theEpidendrum difforme complex is described and illustrated,E. oldemanii. Closely related toE. amapense, E. oldemanii is distinguished by the absence of a midlobe to the labellum.  相似文献   

12.
Association study is the method of choice to identify genes involved in complex processes that result from the interaction of environmental and genetic factors. However, because of biases that increase the risk of false positive reports, preliminary positive conclusions have to be reproduced on other populations to be validated as firm conclusions. In 1994, certain alleles of two genes, APOE (Apolipoprotein E) and ACE (angiotensin converting enzyme), were reported to be more frequent in French centenarians, suggesting an association with such a complex polyfactorial process as longevity. Enlargement of the French centenarian cohort allows a new assessment of this hypothesis on 563 centenarians. In contrast to APOE, the ACE association was not confirmed. Retrospective analysis of the initial study revealed discrepancies that may in part explain this observation. Risk of reporting false positive associations is discussed and recommendations to set up a rigorous experimental design are proposed.  相似文献   

13.
The taxonomic equationsMelanoxylon speciosum Benoist=Recordoxylon amazonicum (Ducke) Ducke andElephantomene eburnea Barneby & Krukoff (1974)=Cionomene javariensis Krukoff (1979) are proposed. The new combinationRecordoxylon speciosum (Benoist) Gazel is validated, and the widely discontinuous distribution of the monotypic genusElephantomene is mapped.  相似文献   

14.
Fissidens saülensis Pursell & Buck is described from central French Guiana. It is most closely related toF. subulatus Mitt. but differs in the broader leaves, smaller laminal cells, and larger stature.  相似文献   

15.
Mortality differentials reflect in part the social and economic conditions of groups in society. In this paper, the relationship between ethnic origin and mortality is investigated from the point of view of convergence and minority group status hypotheses. Multivariate methods are used to study differences among the French, the British and Native Indian (includes Metis and Eskimos) populations of Canada over three census periods from 1951 to 1971. A significant downward trend in the death rates of all three subpopulations is noted, but substantial differences persist, as the pace of mortality decline over time varies across the three ethnic groups. In the twenty-year interval between 1951 and 1971, Native Indians have experienced spectacular reductions in their overall death rates, but in comparative terms, their mortality levels still exceed those of the French (who show intermediate levels) and the British ethnic groups. The multivariate analysis provides strong support for the minority status effect, which is taken to suggest that the roots of inequalities in survival probabilities are partly a result of social and economic disparities. The convergence thesis received some support: over time the general pattern is one of declining mortality with some narrowing of the differences. An examination of four broad causes of death (neoplasms, cardiovascular, accidents-violence, and "other") suggests that Native Indians are characteristic of populations undergoing epidemiologic and demographic transitions. Their elevated risk of accidents-violence reflects social disruption in the process of modernization. Causes of death of the French and British populations are characterized by higher risks of cancer and cardiovascular diseases, typical of advanced societies.  相似文献   

16.
In this study we have examined the reception of Mendelism in France from 1900 to 1940, and the place of some of the extra-Mendelian traditions of research that contributed to the development of genetics in France after World War II. Our major findings are:
(1)  Mendelism was widely disseminated in France and thoroughly understood by many French biologists from 1900 on. With the notable exception of Lucien Cuénot, however, there were few fundamental contributions to the Mendelian tradition, and virtually none from about 1915 to the midthirties. Prior to 1900, Cuénot's work was already marked by a striking interest in physiological mechanisms; his physiological preoccupations played a considerable role in his account of the inheritance of coat color and of susceptibility to tumors in mice. His analysis of the roles of the many genes involved in pigment formation was developed with an eye to one of the first models of the metabolic reactions involved. It yielded one of the earliest suggestions that the steps controlled by single genes involve enzymes as the products of genes.
(2)  The inflexible structure of the French universities played an important role in discouraging research in genetics and in the failure to train the post-World War I generation in that discipline.
(3)  During this period the disciplines of physiology, microbiology, and causal embryology were dominant in French experimental biology. The issues that were most prominent within these disciplines—differentiation and development, regulation of growth and morphology, infection and assimilation—were not easily treated within genetics. The failure of Mendelism to resolve a variety of legitimate explanatory issues to the satisfaction of serious investigators trained in the dominant French disciplines also contributed to the failure of Mendelism to penetrate French science. The violent anti-Mendelian polemics put forward by many of the most committed neo-Lamarckians raised many of the same issues regarding the supposed insufficiency of Mendelism. Cuénot's reluctance to encourage his students to pursue careers in genetics illustrates the compound nature of the resistance.
Despite the absence of a developed tradition of Mendelian research, a French school of molecular genetics had developed by the 1950s. It flourished outside the university system at the Institut Pasteur, the Institut de Biologie physico-chimique, and the CNRS (though some of its leading figures had university connections), and it was only beginning to enter into university curricula. The most important indigenous research that informed the new tradition was that of Eugène Wollman on paraheredity of phage infection and lysogeny, of André Lwoff on the physiology and nutritional requirements of protozoa and bacteria, and the embryologically influenced genetic investigations of Boris Ephrussi. The conceptual and methodological resources of the French school were enriched by this background; a full understanding of the products of the fifties, we believe, requires a proper appreciation of these antecedents. Molecular genetics in France grew out of the Pasteurian tradition of microbiology and the highly developed tradition of causal embryology as modified by Ephrussi. Both of these traditions were extra-Mendelian and not anti-Mendelian, but they both shared a number of the problems and assumptions that were at the center of the extremist resistance to Mendelism. In many respects, then, it is more fruitful to see the entry of French biology into molecular genetics as a development of its microbial-physiological and causal-embryological traditions, coopting the tools and techniques of genetics, rather than the other way around.  相似文献   

17.
As far as nineteenth century Anglosaxons were concerned, French Canadians were not quite white. This article considers the racial dimension of French-Canadian subjugation, long elided and ignored by historians. However, the descendants of French Canadians are no longer construed, and no longer construe themselves, as a racialized group, but rather as a modern, white, western nation. These changes in racial assignment still influence how French and English Canadians make sense of Canadian politics and identities today. Although Quebec's dual majority/minority status in Canada has been well studied, this article also taps into critical race and whiteness studies to examine how notions of evolution, civilization and progress continue to influence how to do things with race in Quebec.  相似文献   

18.
Bothremydidae is the most abundant and diverse group of turtles in the upper Cretaceous fossil sites of southwestern Europe. Several species a priori recognized as exclusive of the Portuguese, Spanish and French records were defined. The most abundant and best-preserved Spanish collection of pleurodiran turtles from the last Stages of the Upper Cretaceous comes from the fossil site of Lo Hueco (Cuenca Province, Central Spain). The bothremydid Iberoccitanemys convenarum, defined by a single specimen from the Maastrichtian of Haute-Garonne (Southern France), was subsequently recognized as a very abundant form in this Spanish site, corresponding to the only bothremydid so far identified as being part of the diversity of Bothremydidae of both countries. The presence of a second member of Bothremydidae was recognized in Lo Hueco, representing the only evidence of the synchronic and sympatric coexistence of two members of this lineage in a European site. However, very scarce information about this second form from Lo Hueco was available. Thus, its attribution to a new taxon or to a member of Foxemydina previously identified in the Spanish record, or in that of other European regions, could not be evaluated until now. New material from Lo Hueco, not attributable to I. convenarum but to this second larger form, allows its generic and specific identification. Close paleobiogeographical relationships considering the fauna of pleurodiran turtles from Spain and France are recognized thanks to the findings performed in Lo Hueco: not only I. convenarum is known in both countries, but also the French Foxemys mechinorum is identified in Central Spain.  相似文献   

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Abstract

This paper explores how French activists use claims about the history and legacies of slavery to combat stigmas associated with their group membership. Using a case study of a French Caribbean association (CM98) and a pan-African association (COFFAD), I examine how two organizations produce competing models for challenging and reversing the stigma of slavery. Through a process of normative inversion, activists assert the moral inferiority of dominant groups. CM98 rejects both a racial and an African identity, and seeks recognition for ‘French descendants of slaves’, using the language of citizenship to criticize the French government. COFFAD, by contrast, asserts an Afro-centric black identity and stigmatizes white Europeans. I argue that both destigmatization strategies unwittingly reinforce the stigma of historical enslavement.  相似文献   

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