共查询到20条相似文献,搜索用时 234 毫秒
1.
Mary Ann Dombrink-Kurtzman William E. Dick Kermit A. Burton Martin C. Cadmus Morey E. Slodki 《Biochemical and biophysical research communications》1983,111(3):798-803
Evidence is presented for the presence of a new lectin activity in soybean seeds [ (L.) Merrill] that has specificity towards the 4-O-methyl--glucurono--rhamnan exopolysaccharide produced by certain strains of . Bacterial agglutination and precipitin reactions revealed the lectin activity in phosphate-buffered saline extracts of seeds of all cultivars tested, including the “lectinless” varieties. Reaction of such extracts with carbohydrate haptens demonstrated that the specificity of the binding was towards 4--methyl--glucuronic acid, -glucuronic acid and their methyl glycosides. 相似文献
2.
OKY-1581 is an effective inhibitor of thromboxane synthesis and . The generation of thromboxane B2 (TxB2), prostaglandin E (PGE) and prostaglandin F (PGF) was measured following clotting and during platelet aggregation induced by collagen. The presence of OKY 1581 either or caused a reduction in TxB2 generation during clotting and platelet aggregation with a concomitant increase in PGE and PGF. The effect could be observed two hours after oral or subcutaneous administration of 5 to 100 mg per rabbit and lasted for 24 to 48 hours. The reduction in TxB2 was not accompanied by an inhibition of clotting or platelet aggregation. OKY-1581 appears to be a suitable agent for studying the role of TxB2 in atherosclerosis. 相似文献
3.
Evelyn A. Devine Mary C. Moran Peter J. Jederlinic Anthony J. Mazaitis Henry J. Vogel 《Biochemical and biophysical research communications》1975,67(4):1589-1593
The transducing phage λd, carrying a portion of the chromosome including , is derived from the heat-inducible, lysis-defective strain λy199, which has the and deletions. Cleavage of λy199 DNA by RI endonuclease, followed by agarose slab gel electrophoresis, results in bands corresponding to the known C, D, E, and F segments of λ, and a segment A′ (A plus B minus minus , the cleavage site between A and B being eliminated). Cleavage of λd DNA by RI yields the expected D, E, and F segments of λ and four other segments, termed 14-1 through 14-4, whose length is 17.5, 6.2, 3.0, and 2.0 kilobases, respectively, as determined by electron microscopy and corroborated by electrophoretic mobility. Heteroduplex analysis shows that the cluster is on the 14-1 segment. 相似文献
4.
The synthesis and characterization of - and -3,4-bis(4-hydroxyphenyl)-2-hexene (- and -pseudo-DES) and of -3,4-bis(4-hydroxyphenyl)-2-hexen-1-ol (-1-hydroxypseudo-DES) are described. These compounds are useful as probes in the study of hormone action. 相似文献
5.
Ronald M. Hamelik Mead M. McCabe 《Biochemical and biophysical research communications》1982,106(3):875-880
An inhibitor of , endodextranase was detected in proteins prepared from batch cultures of , strains representing serotypes through . Affinity chromatography of strain 6715-49 proteins, which apparently were free of endodextranase activity, yielded an active endodextranase and, in a separate peak, the endodextranase inhibitor. The presence of the inhibitor in culture fluids accounts for the absence of endodextranase activity in batch-grown cultures of , known to produce this enzyme. 相似文献
6.
Uterine stage embryos collected from the hamster (8-cell) and cow (morula, early blastocyst) were monitored for development (embryo culture) and (embryo transfer) following premature removal of the zona pellucida.Removal of the zona pellucida did not significantly affect development to the blastocyst stage of (1) 8-cell hamster embryos (zonae removed by a combined enzymic-mechanical procedure), (2) bovine morulae (zonae removed by mechanical means only) (3) early bovine blastocysts (zonae removed by the enzymic-mechanical technique).Zona-free hamster embryos formed significantly fewer viable fetuses than did zona-intact embryos. The lower incidence of fetal development observed following transfer of zona-free 8-cell hamster embryos may have resulted in part from the formation of chimeras by fusion of these embryos . Such fusion was observed to occur between zona-free embryos placed in close proximity. The proportion of pregnancies resulting from transfer of bovine blastocysts cultured from zona-free morulae was similar to that of zona-intact embryos.In this study we have demonstrated that (1) enzymic and mechanical procedures used to remove zonae pellucidae from uterine-stage hamster and bovine embryos do not adversely affect subsequent development of these embryos and and (2) zonae pellucidae are not required for normal development of these embryos. These findings have implications for microsurgery of mammalian embryos and for embryo transfer. 相似文献
7.
Both pairs of -ll-desoxy- and -13---15, 16-dihydroxyprostaglandins have been synthesized via 1,4-conjugate additions of an appropriately functionalized -vinyl cuprate to the requisite cyclopentenone. These prostaglandin analogs are considerably less potent than PGE2 as gastric secretion inhibitors or as bronchodilators. 相似文献
8.
George M. Stancel Judy S. Ireland Venkat R. Mukku Alice K. Robison 《Life sciences》1980,27(12):1111-1117
The pesticide o,p'-DDT stimulates the production of a specific uterine protein, the so-called induced protein or IP, normally associated with an estrogenic response of the uterus. stimulation of IP production is observed 1 hour after the administration of 250 mg/kg of o,p'-DDT to immature rats. stimulation of IP production is observed after a 1 hour incubation of uteri with 100 μM o,p'-DDT. This response is blocked by Actinomycin D. In contrast to o,p'-DDT, which binds to the cytoplasmic estrogen receptor and stimulates IP production, p,p'-DDT which does not bind well to the estrogen receptor does not stimulate IP production . These findings represent the first report of an estrogenic effect of o,p'-DDT in a completely system. 相似文献
9.
Tetsuo Sawai Laura J. Crane J.O. Lampen 《Biochemical and biophysical research communications》1973,53(2):523-530
The plasma membrane-bound penicillinase of has been purified. Amino acid analysis showed no significant differences in composition between the enzyme and exopenicillinase. Enzyme purified from cultures containing H333PO4 or [3H]-glycerol contained 33P or [3H]-glycerol activity and treatment with 8 M urea, 0.2% sodium dodecyl sulfate at 80° C did not remove the 3H-activity from the enzyme protein. Trypsin readily cleaved the glycerol-containing moiety from the enzyme protein, forming enzyme with molecular weight and heat stability like that of the exoenzyme. Phospholipase D and C also produced enzyme resembling the exo-form. 相似文献
10.
Yuji Kamiya Akira Sakurai Nobutaka Takahashi 《Biochemical and biophysical research communications》1980,94(3):855-860
Rhodotorucine which induces mating tube formation of cells in is metabolized rapidly by cells. By use of labeled rhodotorucine , the degradation was found to be proteolytic. Two peptide fragments Tyr-Pro-Glu-Ile-Ser-Trp-Thr-Arg and Asn-Gly-Cys(S-farnesyl) were identified as the metabolites. Proteolysis of the pheromone mainly occurred on the cell surface. Culture filtrate of cells at log phase did not metabolize rhodotorucine . 相似文献
11.
This case report addresses the occurrence of Brucellosis and its effect on the cattle in developing countries. Three Zebu bulls () are presented and the clinical and pathologic signs are described. Conception rates declined following an abortion storm in one herd and without prior abortions in another herd. Semen collected by electro-ejaculation was found to be azoospermic or with very few spermatozoa. was isolated from seminal vesicles, testes and epididymides. Organs affected and showing microscopic lesions were testes, epididymides and seminal vesicles. The latter were not consistently affected. None of the bulls showed impairment of libido or breeding capacity. 相似文献
12.
J.A. Pérez-González A. Jiménez 《Biochemical and biophysical research communications》1984,125(3):895-901
The paromomycin producing organism is resistant to this antibiotic and contains a phosphotransferase which inactivates paromomycin. The gene encoding this enzyme has been inserted in the vector pIJ702 and then cloned in , selecting for paromomycin-resistance. Three plasmids have been isolated and one of them, pMJ1, contains a 2.2 kb insert with a single HindIII restriction site. Insertion of foreign DNA in this site blocks the expression of the phosphotransferase enzyme indicating that it is within the cloned gene. These findings provide a new dominant selective marker for cloning vectors with the versatility of insertional inactivation. 相似文献
13.
The specific synthesis of F mRNA directed by the F gene carried on the specialized transducing bacteriophage F, performed , is described with the use of an S180 extract from a strain carrying R?. Synthesis of F mRNA is biphasic at approximately 7 minutes. The regulation of F mRNA synthesis by the specific arginine holorepressor present in an S180 extract prepared from a strain carrying the R+ allele is described. 相似文献
14.
Daniel H. Riddick Anthony A. Luciano William F. Kusmik Ila A. Maslar 《Life sciences》1978,23(19):1913-1921
Relatively large amounts of immunoreactive prolactin were measured in homogenates of human decidual tissue obtained immediately after delivery of normal term pregnancies. In order to study the release and possible synthesis of prolactin by this tissue, explants of decidua were incubated for 24 hours at 37°C in oxygenated Gey's buffer containing 20% fetal calf serum. When cycloheximide was added to the medium in concentrations sufficient to prevent protein synthesis, 85–90% of the prolactin present in the tissue was released into the medium during the first 3 hours of incubation. No additional prolactin accumulated in either the medium or the tissue during the remainder of the incubation period. In the absence of cycloheximide, the prolactin concentration in the medium increased progressively during incubation, so that after 24 hours the total amount of hormone present in the tissue and medium was significantly greater than that in the tissue and medium prior to incubation (37.6 ± 9.6 ng/ml at 0 time vs 82.2 ± 7.7 ng/ml at 24 hours). When 3H-1-leucine (100 u Ci) was supplied during incubation, radioactive proteins were detected in the medium at 24 hr, 14–20% of which were specifically precipitated by antiserum to human pituitary prolactin. When aliquots of this medium were chromatographed on Sephadex G-100, 80–95% of the 3H-proteins precipitated by antiserum to pituitary prolactin eluted in the same position as did purified, iodinated pituitary prolactin. These data indicate that a species of prolactin which is identical to pituitary prolactin by the criteria of immunoprecipitation and gel chromatography is synthesized by human decidual tissue . 相似文献
15.
Kinji Tsukada Gensaku Okada 《Biochemical and biophysical research communications》1980,94(4):1078-1082
Isozyme patterns of -adenosylmethionine synthetase have been measured with and without dimethylsulfoxide in hepatoma of rats induced by -2-fluorenylacetamide. The isozymes of α- and β-types existing in normal rat liver gradually decreased with the progress of hepatocarcinoma, and the kidney type γ-enzyme appears along with disappearance of both α- and β-enzymes. The liver from rat fetus contains a greater part of γ-type enzyme. 相似文献
16.
Tomasz Twardowski Janet M. Hill Herbert Weissbach 《Biochemical and biophysical research communications》1976,71(3):826-833
Extracts of 40 hr nauplii can convert a heavy form of elongation factor 1 (EF-1H) to a light species (EF-1L). The data indicate that a protease in the extracts is responsible for this reaction, and these findings may explain the observation that extracts from nauplii have only EF-1L whereas before hatching of the embryos EF-1H is the predominant species (Slobin and M?ller [1975] Nature 258, 452–454). 相似文献
17.
S.S.S.V. Prasad Y.I. Shethana 《Biochemical and biophysical research communications》1975,62(3):517-523
The proteinaceous crystal of var was found to enhance humoral immune response in rats and guinea pigs immunised with sheep red blood cells. The enhancement was due to the increased levels of both 19S and 7S antibodies in the sera of the treated animals. A novel synthesis of 7S haemolytic antibodies was observed in case of crystal treated animals. 相似文献
18.
Leonard A. Koltun Joseph LoBue Torgny N. Fredrickson Albert S. Gordon 《Life sciences》1976,19(12):1907-1912
The semi-soft agar colony assay permits an analysis of committed myeloid stem cell (CFU-c) proliferation capacities. In this paper this procedure has been used in combination with prior diffusion chamber culturing to determine the effect of host influences upon this committed stem cell population. This “double-seeding” procedure of first culturing bone marrow cells in diffusion chambers and then re-seeding them in agar furnishes data suggesting a relationship between diffusion chamber transitional lymphocytes and CFU-c seeding capacities. Diffusion chamber culturing offers a means of monitoring granulopoiesis and selects for enrichment of stem cell numbers. Detection and quantification of diffusion chamber stem cell enrichment is easily assessed by seeding chamber contents into the agar colony assay. 相似文献
19.
Normal estrous cycles were established for twenty beef heifers. Ten heifers were inoculated with blood from a known carrier. The inoculated heifers experienced anemia, anorexia, and positive complement-fixing antibody titers, and . was observed on the erythrocytes while uninoculated control heifers remained normal. Further observation following inoculation revealed that five of ten inoculated heifers experienced anestrus while controls continued to cycle normally. Anestrus coincided with clinical signs of acute anaplasmosis. Normal estrus patterns returned following treatment and recovery. This study provides evidence that acute anaplasmosis in beef heifers may cause anestrus and therefore lead to reproductive inefficiency. 相似文献
20.
Yuji Kamiya Akira Sakurai Saburo Tamura Nobutaka Takahashi Keiko Abe Eiko Tsuchiya Sakuzo Fukui Chieko Kitada Masahiko Fujino 《Biochemical and biophysical research communications》1978,83(3):1077-1083
Rhodotorucine is a peptidyl factor which induces mating tube formation in . The amino acid sequence of the factor was determined by Edman degradation and enzymatic hydrolysis. Rhodotorucine was shown to contain a lipophilic amino acid, S-farnesyl cysteine, at C-terminus by proton magnetic resonance, mass spectrometry and chemical synthesis. We proposed the following structure for rhodotorucine . H-Tyr-Pro-Glu-Ile-Ser-Trp-Thr-Arg-Asn-Gly-Cys(S-farnesyl)-OH 相似文献