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81.
Y D Karkhanis R L Anderson J Y Zeltner R Z Maigetter D J Carlo T H Stoudt 《Biochemical and biophysical research communications》1979,89(2):750-758
An antigenic subunit of molecular weight 66,000 daltons has been isolated from the antigenic complex of the Melvin strain of . Incubation of the complex in 8M urea at room temperature for four hours resulted in the dissociation of the subunit from the complex. It was separated from the complex by chromatography of the incubation mixture on a Sepharose 6B column in 50 mM ammonium bicarbonate pH 8.5 without 8M urea and further purified by affinity chromatography. This communication reports on a newly isolated antigenic protein devoid of LPS present in the bacteria. 相似文献
82.
Mario Campa Eleuterio Ferrannini Carlo Garzelli Vittorio Colizzi Giuseppe Falcone 《Current microbiology》1979,2(5):283-286
Pseudomonas aeruginosa infection depresses contact sensitivity to oxazolone in mice. To test whether an altered lymphocyte circulation plays a role
in this depression51Cr-labeled lymphocytes fromP. aeruginosa-infected and oxazolone-sensitized donors were injected intravenously into infected and sensitized recipients, and the radioactivity
uptake of several organs was determine. The controls consisted of normal mice receiving labeled lymphocytes from normal donors.
While the radioactivity recovered from the liver, spleen, and mesenteric lymph nodes was similar in the test and the control
group, significantly more radioactivity was recovered from the draining lymph nodes of infected and sensitized recipients.
The concentration of labeled lymphocytes from sensitized donors in the draining lymph nodes of sensitized recipients was 18%
greater than that of the controls but 31% lower than that of infected and sensitized animals receiving cells from infected
and sensitized donors.P. aeruginosa infection enhances lymphocyte entrapment within the draining lymph nodes of oxazolone-sensitized mice. 相似文献
83.
Umberto Tomati Giovanni Giovannozzi-Sermanni Silvestro Duprè Carlo Cannella 《Phytochemistry》1976,15(5):597-598
The NADH: nitrate reductase from durum wheat leaves was inactivated by cyanide and its activity restored by thiosulphate and beef kidney rhodanese. Rhodanese and thiosulphate, added to NADH-nitrate reductase before cyanide treatment protected NADH-nitrate reductase activity. No oxidizing agent was required for the protection or restoration of cyanide treated NADH-nitrate reductase. 相似文献
84.
J J Jackson A Hagopian D J Carlo G A Limjuco E H Eylar 《Biochimica et biophysica acta》1976,427(1):251-261
The AP1 protein, a unique aspermatogenic protein localized in the sperm acrosome, exists as a single polypeptide chain of 136 amino acids, as shown by a single band on gel electrophoresis in sodium dodecyl sulfate and the recovery of the expected 21 to 22 tryptic peptides on peptide mapping. The AP1 protein appears to exist in a compact, highly stable conformation, as shown by its resistance to trypsin hydrolysis. Its aspermatogenic acitivity is not affected by trypsin treatment, by heating at 99 degrees C for 1 h, by 8 M urea, or by acid conditions. After reduction and alkylation, however, the molecule appears to open up, since it becomes hydrolyzable by trypsin and migrates more slowly on gel electrophoresis at pH 2.7 and 8.6. After alkylation, the AP1 protein still migrates as a single band at pH 2.7. The AP1 protein shows microheterogeneity near its isolectric point at pH 8.6; each of five bands shows the same amino acid analysis. Aggregation was not observed following treatment with dimethylsuberimidate. The molecular weight of 15 000, obtained from gel electrophoresis consists of 136 amino acids with a relatively high content of proline, half cystine, glycine, histidine and tryptophan. No galactose, mannose, fucose, glucose, or hexosamines were found; the AP1 protein is thus not a glycoprotein. 相似文献
85.
86.
Mark L. Johnson Joell B. Hansen James C. Donofrio Carlo M. Veneziale 《Biochimica et Biophysica Acta (BBA)/General Subjects》1981,675(1):140-142
Dexamethasone in the medium perfusin isolated rabbit livers caused a fast-acting and reversible effect on liver pyruvate kinase. The effect was to lower th assayable V activity (units/g tissue) without changing the concentration (nmol/g enzyme protein). In effect, glucocorticoid lowered the specific activity (units/nmol of enzyme) by direct action on liver. The effect on liver pyruvate kinase is mediated by a relatively stable alteration; 30 min after perfusate (with steroid) was replaced by perfusate (without steroid), the effect remained strongly evident. 相似文献
87.
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89.
Abstract The presence, in the North Adriatic sea and in the Chioggia and Marano lagoons, of Pseliodinium vaubanii a rare dinoflagellate species, is reported. Our results showed that Pseliodinium vaubanii is a very frequent and abundant species in these environments. 相似文献
90.
ABSTRACT A phytosociological study of the shrubland communities which colonise abandoned terraced olive groves in the Tyrrhenian district of Central Italy is presented here. The vegetational analysis was carried out using the Braun Blanquet phytosociological approach. Two main types of shrubland communities characterising distinct environmental conditions occur within abandoned terraced olive groves. On the one hand, there are those scrub types which tend to occupy the central part of the terrace; on the other hand, there are the scrubs types which develop along the stone walls bordering the terrace. Different phytosociological associations, sub-associations, and variants ranging from Pistacio-Rhamnetalia alaternii to Prunetalia spinosae are recognised and described. In the warm dry areas, both Myrto-Lentiscetum and Rhamno-Euphorbietum dendroidis occur. Also, a new Oleo-Ceratonion sub-association (Myrto-Lentiscetum spartietosum junceii) is presented here for the first time. In the inner zones of the study area, a range of aspects characterising a new Pruno-Rubion ulmifolii community type (Roso-Rubetum ulmifolii ass. nova) are identified. 相似文献