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41.
Michele Solem Angela Helmrich Paul Collodi David Barnes 《Molecular and cellular biochemistry》1991,100(2):141-149
Summary Human S-protein is a serum glycoprotein that binds and inhibits the activated complement complex, mediates coagulation through interaction with antithrombin III and plasminogen activator inhibitor I, and also functions as a cell adhesion protein through interactions with extracellular matrix and cell plasma membranes. A full length cDNA clone for human S-protein was isolated from a lambda gt11 cDNA library of mRNA from the HepG2 hepatocellular carcinoma cell line using mixed oligonucleotide sequences predicted from the amino-terminal amino acid sequence of human S-protein. The cDNA clone in lambda was subcloned into pUC18 for Southern and Northern blot experiments. Hybridization with radiolabeled human S-protein cDNA revealed a single copy gene encoding S-protein in human and mouse genomic DNA. In addition, the S-protein gene was detected in monkey, rat, dog, cow and rabbit genomic DNA. A 1.7 Kb mRNA for S-protein was detected in RNA from human liver and from the PLC/PRF5 human hepatoma cell line. No S-protein mRNA was detected in mRNA from human lung, placenta, or leukocytes or in total RNA from cultured human embryonal rhabdomyosarcoma (RD cell line) or cultured human fibroblasts from embryonic lung (IMR90 cell line) and neonatal foreskin. A 1.6 Kb mRNA for S-protein was detected in mRNA from mouse liver and brain. No S-protein mRNA was detected in mRNA from mouse skeletal muscle, kidney, heart or testis. 相似文献
42.
Onychomycosis caused by Scopulariopsis brumptii 总被引:1,自引:0,他引:1
Scopulariopsis brumptii was isolated from nail lesions in left hand of a 42 year-old-farmer. The direct microscopic examination of the nail samples revealed light brown, septate, branched fungal hyphae along with thick-walled spherical cells. The histopathological examination showed involvement of internal phase of the nail plate. Amongst the antimycotics tested against S. brumptii In vitro oxiconazole was found to be the most active with MIC value of 10 g/ml–1. This report documents the first instance of onychomycosis caused by S. brumptii. 相似文献
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Summary A pot experiment with lettuce involving three N forms each at six application levels, showed that lettuce can be grown satisfactorily
with a very low nitrate content when supplied with ammonium sulphate and a nitrification inhibitor. For plants growing on
nitrate N, the optimum midrib sap nitrate concentration as maturity approached was about 1400 mg/1 NO3-N. Large losses of mineral N were observed from the peat medium, even in the absence of plants.
A relationship is presented which would enable a lettuce grower to estimate whole-shoot nitrate concentration from a quick
test of midrib sapi.e. NO3-N (mg/kg in fresh shoot) =0.14×NO3-N (mg/l in sap).
Tipburn was worst at intermediate levels of applied N, and was less serious with pure ammonium nutrition than with nitrate. 相似文献
47.
Philip Skehan James E. Thomas Susan J. Friedman 《In vitro cellular & developmental biology. Plant》1986,22(11):632-636
Summary Sarcoma 180 monolayers spontaneously shed single cells and small multicellular aggregates into the surrounding medium to produce
a dual population of floating and substratum-attached cells. Shedding was a motility-associated event that occurred when cells
attempted to migrate over one another. It resulted from a combination of cell shape change and active motility, which increased
sensitivity to fluid shear dislodgement by reducing a cell's surface area of adhesive contact and increasing strain tension
at its adhesive contact points. Shedding occurred at all phases of the cell cycle. Extracellular matrix but not conditioned
medium enhanced the floating subpopulation by slowing the kinetics of rattachment to plastic and cellular substrata. Although
sarcoma 180 cells are anchorage independent in the sense that they grow readily in single cell suspension, they nevertheless
exhibited anchorage modulation of their cell cycle. Short periods in suspension produced a mild G1 accumulation, whereas longer periods of anchorage deprivation led to a mild G2 accumulation which appeared to result from an interference with cytokinesis.
This work was supported by grants from the Medical Research Council of Canada, The National Cancer Institute of Canada, the
Alberta Heritage Savings and Trust Fund for Applied Cancer Research, and the Alberta Heritage Fund for Medical Research. 相似文献
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Current investigations concerning the identification of the chemical nature of the oviposition deterring pheromone of the European cherry fruit fly, Rhagoletis cerasi L., are conducted in an interdisciplinary research program by combining chemistry with behavioral evaluation. The methods used to collect and evaluate the pheromone by an improved semi-quantitative behavior test are described.
Zusammenfassung Nach einer einleitenden Übersicht über den heutigen Stand der Erkenntnisse auf dem Gebiet der eiablage-hemmenden Pheromone (ODP) bei Fruchtfliegen und insbesondere der Kirschenfliege wird der verbesserte Verhaltenstest beschrieben, welcher für den halb-quantitativen Nachweis von ODP-Aktivität entwickelt worden ist. Im laufenden interdisziplinären Forschungsprogramm an der Eidg. Forschungsanstalt Wädenswil wird versucht, durch enge Zusammenarbeit zwischen Biologe, Chemiker und Elektrophysiologe das ODP der Kirschenfliege möglichst mit geringem Anteil an Verunreinigung einzusammeln, zu reinigen und einer chemischen Identifikation der ODP Komponenten zugänglich zu machen.Die Möglichkeiten und Grenzen des Verhaltenstests werden diskutiert und die Empfindlichkeit des Verfahrens mittels einer Konzentrationsreihe von Pheromonextrakt aufgezeigt.相似文献
50.
Trypanosoma brucei: analysis of relapsing populations in sensitive and resistant breeds of cattle 总被引:1,自引:0,他引:1
G E Roelants G Duvallet W Hirsch B Kanwe M Pinder G Guidot G Libeau A Van Melick 《Experimental parasitology》1985,60(1):18-31
The clone DiTat 1.1 of Trypanosoma brucei brucei was injected into four bovids, and clones obtained from successive waves of parasitemia were used to study the expressed variant-specific surface glycoprotein repertoire. Twenty-four clones were obtained which could be classified into 12 different variable antigen types, in addition to the clone injected, using agglutination or immunofluorescence with monospecific antisera. The variable surface glycoproteins of the 25 clones were extracted using the detergent octyl-beta-D-glucopyranoside in the presence of the protease inhibitor, N-cbz-L-phenylalaninechloromethylketone. The molecular weights varied from 52,000 to 69,000 and the pI from 5.0 to 8.8. The virulence of 14 clones representing 13 variable antigen types was ascertained in mice. The mean survival time ranged from 20.5 to 43.0 days. Clones isolated from early peaks of parasitemia in the bovid were the most virulent while clones derived from later peaks were less virulent. It seems that organisms of diminishing virulence appear in bovids, leading to self-cure of the disease. All clones were sensitive to human serum in a blood infectivity inhibition test. Antibody against all virulent clones appeared in 20 cattle (10 Zebus, 10 Baoulés) which had been injected with T. brucei DiTat 1.1. There was no evidence for parasites of high or low virulence being preferentially expressed in resistant or sensitive hosts. 相似文献