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41.
Thrombin modulates vectorial secretion of extracellular matrix proteins in cultured endothelial cells 总被引:5,自引:0,他引:5
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Max Hayman 《The Western journal of medicine》1955,83(6):435-440
The one approach most favored for alcoholism by psychiatrists in Southern California who answered a questionnaire is membership in Alcoholics Anonymous. Ninety-nine per cent of them approved Alcoholics Anonymous, and 80 per cent had referred patients to the organization. Yet they believed only 10 per cent of the persons who join A.A. remain sober for over two years. This against the claim of A.A. that 60 per cent or more of their fellowship are recovered emphasized the pessimism of the psychiatrists questioned.Ninety per cent of the psychiatrists who replied said they do not treat alcoholics or that they limit the number or the type they will accept for treatment. They obtain recovery, they said, of 10 per cent of patients, improvement of 50 per cent, and the rest are unchanged.The emphasis in psychiatry is on elimination of the anxieties leading to alcoholism; in Alcoholics Anonymous the emphasis is on the strength to bear these anxieties. Ninety per cent of the replies received were in favor of clinics for alcoholics, and the respondents felt that governmental agencies should support these clinics. Under such circumstances psychiatrists would combine their abilities with psychologists, social workers and Alcoholics Anonymous. Thirty-five per cent of psychiatrists said they are willing to work in a clinic, the majority without recompense. 相似文献
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46.
Parallel mosaicism of supernumerary chromosomes and sex chromosomes in Echymipera kalabu (Marsupialia) 总被引:1,自引:0,他引:1
Echymipera kalabu (Peramelidae: Marsupialia) does not have the full chromosome complement in all its adult somatic tissues. The chromosomes missing are the Y-chromosome in the male and an X-chromosome in the female. The full complement is present in the corneal epithelium and the reproductive tissue. A parallel mosaicism to this exists with respect to small supernumerary chromosomes which are found in certain animals of this species. These supernumeraries must be subject to the same control system as that which is responsible for the elimination of the sex chromosomes. 相似文献
47.
Patricia R Facciotti Rose EG Rici Durvanei A Maria Marcelo Bertolini Carlos E Ambrósio Maria A Miglino 《Reproductive biology and endocrinology : RB&E》2009,7(1):25-7
Background
Placental and fetal growth requires high rates of cellular turnover and differentiation, which contributes to conceptus development. The trophoblast has unique properties and a wide range of metabolic, endocrine and angiogenic functions, but the proliferative profile of the bovine placenta characterized by flow cytometry analysis and its role in fetal development are currently uncharacterized. Complete understanding of placental apoptotic and proliferative rates may be relevant to development, especially if related to the pathogenesis of pregnancy losses and placental abnormalities. 相似文献48.
Nili Raz Yael Danin-Poleg Ryan B. Hayman Yudi Bar-On Alex Linetsky Michael Shmoish Eva Sanjuán Carmen Amaro David R. Walt Yechezkel Kashi 《PloS one》2014,9(12)
Vibrio vulnificus is an aquatic bacterium and an important human pathogen. Strains of V. vulnificus are classified into three different biotypes. The newly emerged biotype 3 has been found to be clonal and restricted to Israel. In the family Vibrionaceae, horizontal gene transfer is the main mechanism responsible for the emergence of new pathogen groups. To better understand the evolution of the bacterium, and in particular to trace the evolution of biotype 3, we performed genome-wide SNP genotyping of 254 clinical and environmental V. vulnificus isolates with worldwide distribution recovered over a 30-year period, representing all phylogeny groups. A custom single-nucleotide polymorphism (SNP) array implemented on the Illumina GoldenGate platform was developed based on 570 SNPs randomly distributed throughout the genome. In general, the genotyping results divided the V. vulnificus species into three main phylogenetic lineages and an additional subgroup, clade B, consisting of environmental and clinical isolates from Israel. Data analysis suggested that 69% of biotype 3 SNPs are similar to SNPs from clade B, indicating that biotype 3 and clade B have a common ancestor. The rest of the biotype 3 SNPs were scattered along the biotype 3 genome, probably representing multiple chromosomal segments that may have been horizontally inserted into the clade B recipient core genome from other phylogroups or bacterial species sharing the same ecological niche. Results emphasize the continuous evolution of V. vulnificus and support the emergence of new pathogenic groups within this species as a recurrent phenomenon. Our findings contribute to a broader understanding of the evolution of this human pathogen. 相似文献
49.
Michael J. Hayman Gary M. Ramsay Keith Savin Gay Kitchener Thomas Graf Hartmut Beug 《Cell》1983,32(2):579-588
Avian erythroblastosis virus causes erythroid leukemia and sarcomas in chickens. The viral oncogene responsible for these diseases, erb, is divided into two regions known as erbA and erbB, and recent evidence suggests that it is the erbB gene that is responsible for the transforming activity. From rats bearing avian erythroblastosis virus-induced sarcomas, we have obtained antisera which are specific for the erb gene products. Using such antisera, we have been able to characterize the erbB gene product as a 68,000 molecular weight protein. Pulse-chase and cell-free in vitro translation experiments show that the initial product is a 62,500 dalton protein which is initially modified to a 66,000 dalton protein, and then further modified to a 68,000 dalton form. These modifications could be shown to be associated with glycosylation and phosphorylation. Cell fractionation experiments revealed that the 66,000 and 68,000 dalton proteins were located in cell membrane fractions, and immunofluorescence results showed the erbB gene product to be expressed on the cell surface. 相似文献
50.
van der Sluis C Smit BA Hartmans S ter Schure EG Tramper J Wijffels RH 《Enzyme and microbial technology》2000,27(1-2):151-156
To elucidate the growth inhibitory effect of threonine, the regulation of the aspartate-derived amino-acid metabolism in Zygosaccharomyces rouxii, an important yeast for the flavor development in soy sauce, was investigated. It was shown that threonine inhibited the growth of Z. rouxii by blocking the methionine synthesis. It seemed that threonine blocked this synthesis by inhibiting the conversion of aspartate. In addition, it was shown that the growth of Z. rouxii, unlike that of Saccharomyces cerevisiae, was not inhibited by the herbicide sulfometuron methyl (SMM). From enzyme assays, it was concluded that the acetohydroxy acid synthase in Z. rouxii, unlike that in S. cerevisiae, was not sensitive to SMM. Furthermore, the enzyme assays demonstrated that the activity of threonine deaminase in Z. rouxii, like in S. cerevisiae, was strongly inhibited by isoleucine and stimulated by valine. From this work, it is clear that the aspartate-derived amino-acid metabolism in Z. rouxii only partly resembles that in S. cerevisiae. 相似文献