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81.
82.
Michel Y. Popoff Colette Coynault Martine Kiredjian Muguette Lemelin 《Current microbiology》1981,5(2):109-114
Relatedness among 55 motileAeromonas strains was assessed by determining the extent of reassociation in heterologous DNA preparations. S1 nuclease and diethylaminoethyl-cellulose filters were used to separate reassociated nucleotide sequences from nonreassociated sequences and to determine the thermal stability of related nucleotide sequences. The motile aeromonads would presently consist of three species:A. hydrophila (type strain ATCC 7966),A. caviae (type strain ATCC 15468), andA. sobria (type strain CIP 7433). These three species are clearly separated on the basis of both biochemical characteristics and similarities in DNA. Each of these three species contains more than one hybridization group: three groups inA. hydrophila; two groups inA. caviae; and at least two groups inA. sobria. DNA hybridization groups are biochemically similar within each species. When additional data is available, these separate DNA hybridization groups may merit designation. Any decision to delineate species in terms of DNA hybridization groups must await a phenotypic basis for their separation. 相似文献
83.
The search for C allotypes as defined by the markers common to domestic rabbits (Oryctolagus) was extended to additional lagomorphs of the familiesLeporidae andOchotonidae. None of theOchotona sera obtained from Afghanistan and Iran (Ochotona rufescens) exhibited the d11, d12, or e14 allotypes. The e15 marker was detected only by radioimmune binding assays. Comparative inhibition of binding assays revealed similarities with other lagomorphs with respect to the e15i determinant. As in some variants of hare e15 markers, the e15j determinant is absent inOchotona. The results provided a revised phylogenetic scheme for the evolution of the C gene on the basis of the e-series allotypes. 相似文献
84.
A new enkephalin analogue: trans-4-hydroxycinnamoyl-glycyl-glycyl-phenylalanyl-leucine. Synthesis and biological properties 总被引:1,自引:0,他引:1
C Amar E Vilkas S Laurent B Gautray H Schmitt 《International journal of peptide and protein research》1983,22(4):434-436
A new analogue of the leucine-enkephalin in which the N-terminal tyrosine has been replaced by trans-4-hydroxycinnamic acid, has been synthetized by liquid-phase coupling methods. The central cardiovascular effects of this analogue were investigated and the results discussed. 相似文献
85.
The uptake of hyaluronan (HYA) labeled with 3H in its acetyl group was measured in cultured liver endothelial cells from normal rats and from rats previously treated with sublethal doses of Escherichia coli endotoxin (ET). Replicate cultures were also exposed to recombinant human tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1) or interferon-gamma for 1 to 3 h before the measurement of hyaluronan uptake. Under all conditions, HYA was absorbed by endothelial cells at rates consistent with receptor-mediated absorption. In cells exposed to HYA 20 h after isolation, rate of uptake was less than half the rate in cells exposed 6 or 7 h after isolation. Cellular uptake of HYA was neither reduced nor enhanced by any of the treatments with cytokines. Prior exposure of the cell donors to ET caused a three-fold increase in their plasma HYA but did not alter the subsequent rate of cellular HYA uptake in vitro, either with or without added treatment with TNF-alpha or IL-1. It was concluded that the elevation of plasma HYA caused by septicaemia or by the experimental administration of ET or TNF-alpha cannot be attributed to direct interference with HYA receptors on hepatic endothelial cells. 相似文献
86.
A Salustri M Yanagishita C B Underhill T C Laurent V C Hascall 《Developmental biology》1992,151(2):541-551
Mural and cumulus granulosa cells synthesize hyaluronic acid (HA) and expand in vitro in response to follicle-stimulating hormone and a soluble factor(s) produced by fully grown oocytes. In the present study we examined HA synthesis and extracellular matrix organization by the two cell populations in vivo during the preovulatory period. After injection of human chorionic gonadotropin into pregnant mares' serum gonadotropin-primed animals, a progressive increase in HA synthesis was observed by the cumulus cell-oocyte complex (COC), and by the mural granulosa cells adjacent to the antrum (antral granulosa cells). The outermost layers of mural granulosa cells (peripheral granulosa cells) did not synthesize HA. Net HA synthesis was approximately 4 pg/cell for COCs isolated after full expansion induced either in vivo or in vitro, whereas the total HA content and cell number in the ovulated COC (approximately 11 ng HA and approximately 3000 cells per COC) were about threefold higher than for COCs expanded in vitro (approximately 4 ng HA and approximately 1000 cells per COC). The increased cell content of ovulated COCs appears to be primarily the result of inclusion of proximal mural granulosa cells which synthesize HA in response to the oocyte factor(s) and become incorporated in the expanded COC extracellular matrix mass. Media conditioned by oocytes enclosed in the cumulus cell mass (intact COCs) contained only 10-20% of the HA-stimulatory activity of media conditioned by an equal number of isolated oocytes when tested on mural granulosa cell cultures. Further, HA-stimulatory activity of media conditioned by isolated oocytes was dramatically reduced (approximately 70%) by preincubation for 5 hr with cumulus cells compared to preincubation in the absence of cells. The results suggest that differences in HA synthesis between subregions of membrana granulosa depend on a diffusion gradient of the oocyte factor(s). 相似文献
87.
C Bernard C Mougin M Rossel R Laurent M Lab 《Comptes rendus des séances de la Société de biologie et de ses filiales》1992,186(3):231-241
Infection with specific types of HPV has emerged as necessary but not sufficient factor in the neoplastic transformation of anogenital condylomas. Some viruses (HIV, Herpes viridae: HSV, CMV, EBV) might act as cofactors in the neoplastic changes and cancer. To study the prevalence of these viral pathogens in anogenital lesions, biopsies were obtained from HIV seropositive or seronegative men and tested using in situ hybridization technique. Infection by "high risk" HPV, HSV and CMV are facilitated in patients immunocompromised by HIV. Presence of CMV is more frequent in high risk HPV-induced lesions than in low risk HPV lesions. 相似文献
88.
Jean-Frédéric Brun Colette Fons Michelle Fussellier Lucette Bardet André Orsetti 《Biological trace element research》1992,32(1-3):317-323
We investigated whether zincuria is associated with microalbuminuria in type I (insulin-dependent) diabetics (IDDM). In 169
IDDM, 215 overnight urine samples were collected for simultaneous assay of zinc and albumin. In 76 samples with excessive
microalbuminuria (>15 mg/L), zincuria was higher than in the 139 other samples (0.83±0.06 vs 0.58±0.03 mg/Lp<0.001), though zincuria and microalbuminuria were not significantly correlated. An exercise provocation test was performed
in 78 IDDM. Although microalbuminuria increased, zincuria did not change during the test. Another group of 83 IDDM underwent
urinary zinc determination over a period of 1 h of recumbency. The 48 patients who had a zincuria higher than the mean+2 SD
of control values had higher microalbuminuria at rest (48±16 μg/min vs 12±2p<0.01) and after exercise (111±33 vs 42±14p<0.02) than the remaining 35 subjects. Both subgroups did not differ for zinc intake and zincemia. Thus, incipient nephropathy
as detected by the measurement of microalbuminuria is associated with a highly significant increase in zinc excretion, which
is not proportional to albumin leakage, nor is it amplified during exercise. Hyperzincuria is not explained by an increase
in zinc intake and does not result in hypozincemia. 相似文献
89.
An electrophoretic survey of blood markers of the Arabian oryx (Oryx leucoryx) was undertaken in order to ascertain the genetic variability in a sample of 85 individuals, mainly from Saudi Arabian (Taíf) and Jordanian herds. Three out of 18 loci were found to be polymorphic (P = 16.7%) and the mean heterozygosity (H = 0.052) appears to be relatively high with respect to the severe demographic bottlenecks expressed by the species since the 1960s. No genetic differentiation was found between Arabian and Jordanian samples considered. Consequences of these findings for the management of the Taíf herd and for such procedures as pedigree determination are discussed, and an example of this latter application is given for a case of doubtful parentage. 相似文献
90.
Susan J. Laurent Maija I. Mednieks Robert L. Rosenfield 《In vitro cellular & developmental biology. Animal》1992,28(2):83-89
Summary Rat preputial cells were grown in an epithelial cell primary monolayer culture system identical to that used for culturing
epidermal cells, which were studied for comparison. Despite similar appearance when observed by phase contrast microscopy,
other features identified the preputial cells as a unique epithelial cell population. Preputial cells grew as a relatively
small number of large colonies, formed domes before confluence, and expressed a specific acinar keratin, K4, which had previously
been found in human sebaceous glands. In addition, preputial cells formed fewer cornified envelopes than epidermal cells,
too few to discern the reduction of envelope formation by retinoic acid treatment in vitro which was found in epidermal cells.
Rat preputial cells in monolayer culture, therefore, are a promising model for studying the effects of hormones on sebaceous
cell growth and differentiation. 相似文献