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By use of Laurell's method, the quantitative evolution of three antigenic components of chicken erythrocyte non-hemoglobin proteins has been followed during the course of development. One of the constituents has been characterized as the yellow component previously described and its evolution has been confirmed. The significance of these modifications is discussed. 相似文献
264.
Allan Raffard Julien Cucherousset Jos M. Montoya Murielle Richard Samson Acoca-Pidolle Camille Posy Alexandre Garreau Frdric Santoul Simon Blanchet 《PLoS biology》2021,19(3)
Loss in intraspecific diversity can alter ecosystem functions, but the underlying mechanisms are still elusive, and intraspecific biodiversity–ecosystem function (iBEF) relationships have been restrained to primary producers. Here, we manipulated genetic and functional richness of a fish consumer (Phoxinus phoxinus) to test whether iBEF relationships exist in consumer species and whether they are more likely sustained by genetic or functional richness. We found that both genotypic and functional richness affected ecosystem functioning, either independently or interactively. Loss in genotypic richness reduced benthic invertebrate diversity consistently across functional richness treatments, whereas it reduced zooplankton diversity only when functional richness was high. Finally, losses in genotypic and functional richness altered functions (decomposition) through trophic cascades. We concluded that iBEF relationships lead to substantial top-down effects on entire food chains. The loss of genotypic richness impacted ecological properties as much as the loss of functional richness, probably because it sustains “cryptic” functional diversity.Global change is expected to generate a loss of intraspecific diversity worldwide. This mesocosm study explores whether loss of genetic and functional diversity in a predator species affects community and ecosystem functioning of lower trophic levels in pond ecosystems, revealing that diversity loss in a single consumer species can impact an entire ecosystem, reducing its functionality. 相似文献
265.
In a statistical analysis of 360 cases of ectopic pregnancy admitted to the Montreal General Hospital over a 20-year period ending December 1964, ectopic gestation occurred once in every 83 admissions to the gynecological service. This incidence has remained constant over the years. Only one out of four patients had had more than one child and 30% of the patients had absolute or relative infertility. Diagnosis was delayed or not made in 58 patients. There was evidence that neurogenic factors play a role in the etiology of ectopic gestation. Ten per cent of the patients had had a previous operation for the same condition. Symptomatology is variable and the possibility of ectopic pregnancy must never be overlooked in a woman of child-bearing age. Once the diagnosis is made the treatment is early operation. The morbidity rate in this series was 28% and there was one death. 相似文献
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J. P. Vandecasteele D. Blanchet J. P. Tassin A. M. Bonamy L. Guerrillot 《Engineering in Life Science》1983,3(4):339-344
A study of alkane degradation in Pseudomonas aeruginosa has been carried out over the last twelve years in the author's laboratory. This study has been aimed at the detailed characterization of the enzymes involved in alkane oxidation to fatty acids, alkane hydroxylase, alcohol dehydrogenase and aldehyde dehydrogenase. Here are summarized the main results of this study and described with some more detail the points which have not yet been reported. Some general conclusions which can be drawn from the evidence obtained are presented. 相似文献
268.
M Autiero R Culerrier C Bouchier S Basmaciogullari M Gaubin S El Marhomy P Blanchet V Paradis A Jardin J Guardiola D Piatier-Tonneau 《DNA and cell biology》1999,18(6):481-487
The PIP gene, localized in the 7q34 region that contains a number of fragile sites such as FRA 7H and FRA TI, codes for gp17/PIP, a protein secreted by breast apocrine tumors. We analyzed the integrity of this gene in 20 tumors of the urogenital tract. We found rearranged EcoRI fragments in 5 of 15 primary prostate carcinomas. No rearrangement was found in normal prostates derived from five patients undergoing prostatocystectomy during treatment of bladder cancers. By Southern blot hybridization with PIP gene exon-specific probes, the rearrangements were mapped at or near the 3' end of the gene. These abnormalities were found, not only in the neoplastic cells invading the prostatic tissues, but also in seminal vesicles without histologic tumoral features. These data suggest a critical role of the PIP gene or neighboring genes in prostate cancer. 相似文献
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Involvement of glutamatergic system of amygdala in generalized seizures induced by soman: comparison with the hippocampus] 总被引:1,自引:0,他引:1
G Lallement P Carpentier A Collet I Pernot-Marino D Baubichon H Sentenac-Roumanou G Blanchet 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1991,313(9):421-426
During seizures induced by soman, an organophosphorus compound, irreversible inhibitor of acetylcholinesterase, the intra-amygdaloid microdialysis of extracellular glutamate, an excitatory amino-acid, showed a sustained increase, more rapid than in hippocampus. This result suggests an early involvement of the amygdala in the development of soman-induced seizures. Moreover, the ex vivo, study by quantitative autoradiography of the binding of tritiated TCP (thienyl-phencyclidine) does not reveal an opening of ionic channels linked to N-methyl-D-aspartate (NMDA) sensitive receptors of glutamate, during seizures, unlike in the hippocampus. This difference could indicate, according to other experimental models, that in amygdala the release of glutamate could occur massively without repeated stimuli as in the hippocampus. 相似文献