首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
An experiment was conducted to assess the effects of estrogen or parturition on absorption of endotoxin from the ovine uterus. Twelve cycling ewes were assigned to one of four treatment groups (three ewes/group): Group I, no estrogen (NE) + intrauterine infusion of sterile saline (IUS); Group II, NE + intrauterine infusion of 100 mg endotoxin - Lipopolysaccharide W./E.coli 0127:B8, Difco Laboratories, Detroit, MI (IUE); Group III, 3 days pretreatment with estradiol-17β (50 μg/da, E) + IUS; and Group IV, E + IUE. In addition, the uteri of three early postpartum ewes were infused with 100 mg endotoxin (Group V). Rectal temperatures (RT) and jugular blood samples were obtained at ?40, ?20, 0 (infusion), 20, 40, 60, 80, 100, 120, 180, and 240 minutes. The blood samples were analyzed for total white blood cell counts (WBC) and Limulus Amebocyte Lysate Assays (LAL). There were no alterations in RT, WBC, or LAL observed in Groups I–V. These results indicated that neither prior treatment with estradiol in cycling ewes nor parturition affected absorption of E.coli endotoxin from the ovine uterus.A second study was conducted to characterize the changes in RT, WBC, and LAL during endotoxemia in cycling ewes. Three ewes received intraperitoneal infusions of 100 mg endotoxin and three ewes received intraperitoneal infusions of sterile saline. Evidence that endotoxin was absorbed from the peritoneal cavity was a decrease (P<0.10) in WBC and positive LAL in endotoxin-infused ewes. WBC and LAL did not change in saline-infused ewes. No changes in RT were observed in either group.  相似文献   

2.
The transducing phage λdarg14, carrying a portion of the E. coli chromosome including argECBH, is derived from the heat-inducible, lysis-defective strain λy199, which has the b519 and b515 deletions. Cleavage of λy199 DNA by EcoRI 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 b519 minus b515, the cleavage site between A and B being eliminated). Cleavage of λdarg14 DNA by EcoRI 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 E. coli argECBH cluster is on the 14-1 segment.  相似文献   

3.
OKY-1581 is an effective inhibitor of thromboxane synthesis invivo and invitro. 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 invivo or invitro 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   

4.
Uterine stage embryos collected from the hamster (8-cell) and cow (morula, early blastocyst) were monitored for development invitro (embryo culture) and invivo (embryo transfer) following premature removal of the zona pellucida.Removal of the zona pellucida did not significantly affect invitro 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 inutero. Such fusion was observed to occur invitro 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 invitro and invivo 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   

5.
Normal estrous cycles were established for twenty beef heifers. Ten heifers were inoculated with blood from a known Anaplasmamarginale carrier. The inoculated heifers experienced anemia, anorexia, and positive Anaplasmamarginale complement-fixing antibody titers, and A. marginale 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   

6.
This case report addresses the occurrence of Brucellosis and its effect on the cattle in developing countries. Three Zebu bulls (Bosindicus) 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. B. abortus 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   

7.
The synthesis and characterization of E- and Z-3,4-bis(4-hydroxyphenyl)-2-hexene (E- and Z-pseudo-DES) and of Z-3,4-bis(4-hydroxyphenyl)-2-hexen-1-ol (Z-1-hydroxypseudo-DES) are described. These compounds are useful as probes in the study of hormone action.  相似文献   

8.
Cells of E. coli C thy?321 are examined for thymine residue release from DNA following gamma-irradiation from 5 to 15 krad. Experimental conditions are designed to inhibit enzyme activity that might promote base residue release. Enzyme action is restricted in order to assess the physicochemical action of radiation on cellular DNA, and to this end irradiation is done under O2, N2, and N2O saturating conditions. Both thymine and thymidine release from bacterial DNA are detected and quantitated, and three oxygen effects are noted in comparing yields of these products. No difference in effect is observed between N2 and N2O gassing conditions, suggesting that the hydroxyl radical has little effect on thymine or thymidine release from irradiated DNA in vivo.  相似文献   

9.
The minichromosome pWS6 was unstable in Escherichia,coli K-12 but became stable upon transfer to Salmonella,typhimurium. The instability of pWS6 was restored when pWS6 was brought back to E.,coli, an observation consistent with the proposed phenomena of chromosomal incompatibility.  相似文献   

10.
Both pairs of dl-ll-desoxy- and dl-13-cis-erythro-15, 16-dihydroxyprostaglandins have been synthesized via 1,4-conjugate additions of an appropriately functionalized cis-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   

11.
12.
Two experiments were conducted to test for the recovery of brucella organisms from uterine flushings and harvested embryos of sero-positive embryo donor females. In Experiment I, 16 sero-positive cows were superovulated with FSH treatments and artificially inseminated at 12, 24 and 36 hours following the onset of estrus with brucella-free semen. At 48 hours after the onset of estrus, one half the potential donor females were administered an intrauterine inoculation of 3.3 to 4.6 × 104Brucellaabortus (strain 2308) organisms while the remainder received a control inoculation. In Experiment II, the same 16 cows were similarly administered superovulatory treatments and inseminated following estrus. The uterine inoculation was increased to 1.5 to 2.5 × 108 organisms administered 48 hours following estrus. Samples of recovered flushing medium and homogenized embryo residues were placed into a validated invitro culture system to detect the presence of brucella bacteria. Uterine flushings and embryos recovered from 31 females exhibiting estrus following FSH treatments were free from either field strain or the inoculated B.abortus (strain 2308) contamination. The flushings obtained from a single female, which did not respond with estrus following FSH treatment but was inoculated at appointment, did contain B.abortus which was identified as the inoculated strain 2308 and not field strain organisms. These results indicate that brucella contamination of flushing media and harvested embryos will not likely be incurred when collecting embryos from sero-positive donor females. These findings offer further encouragement for the use of embryo transplantation as a method to produce brucella-free offspring from infected cows.  相似文献   

13.
The paromomycin producing organism Streptomycesrimosusforma paromomycinus is resistant to this antibiotic and contains a phosphotransferase which inactivates paromomycin. The gene encoding this enzyme has been inserted in the Streptomyces vector pIJ702 and then cloned in Streptomyceslividans, 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 Streptomyces cloning vectors with the versatility of insertional inactivation.  相似文献   

14.
Rhodotorucine A which induces mating tube formation of a cells in Rhodosporidiumtoruloides is metabolized rapidly by a cells. By use of labeled rhodotorucine A, 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 a cells at log phase did not metabolize rhodotorucine A.  相似文献   

15.
Genetic transformation of E.coli for various chromosomal markers was accomplished by (i) using recipient cells that lack the recBC DNase but were recombination proficient due to sbcA or sbcB mutations and (ii) treating the recipient cells with CaCl2 at a concentration that facilitates transfection by λ DNA. Cotransformation of three markers (thr+ara+.leu+) was found to depend on the molecular weight of the transforming DNA.  相似文献   

16.
Evidence is presented for the presence of a new lectin activity in soybean seeds [Glycinemax (L.) Merrill] that has specificity towards the 4-O-methyl-D-glucurono-L-rhamnan exopolysaccharide produced by certain strains of Rhizobiumjaponicum. 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-O-methyl-D-glucuronic acid, D-glucuronic acid and their methyl glycosides.  相似文献   

17.
1-O-Octadec-cis-11-enyl glycerol, paramecyl alcohol, was isolated from Parameciumtetraurelia and P.caudatum phospholipids. This isomer of 1-O-octadec-9-enyl glycerol, selachyl alcohol, had not been previously reported as a component of naturally-occurring phospholipids. The preliminary characterization of the structure of this compound was determined by 1) gas chromatography of the parent compound as well as the products following hydrogenation, ozonolysis and oxidation, 2) mass spectrometry of the parent compound and an oxidation product, 3) infrared spectroscopy, and 4) proton magnetic resonance.  相似文献   

18.
The specific synthesis of argF mRNA directed by the argF gene carried on the specialized transducing bacteriophage λh80C1857dargF, performed in vitro, is described with the use of an S180 extract from a strain carrying argR?. Synthesis of argF mRNA is biphasic at approximately 7 minutes. The regulation of argF mRNA synthesis by the specific arginine holorepressor present in an S180 extract prepared from a strain carrying the argR+ allele is described.  相似文献   

19.
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. Invivo stimulation of IP production is observed 1 hour after the administration of 250 mg/kg of o,p'-DDT to immature rats. Invitro stimulation of IP production is observed after a 1 hour incubation of uteri with 100 μM o,p'-DDT. This invitro 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 invitro. These findings represent the first report of an estrogenic effect of o,p'-DDT in a completely invitro system.  相似文献   

20.
Penicilliumcharlesii incorporates 3H or 14C from 3H- or 14C-labeled ethanolamine into an -alkali soluble, alcohol -insoluble fraction obtained from cell walls. Dansyl ethanolamine was isolated from this alcohol-insoluble fraction following dansylation and hydrolysis. The alcohol-insoluble material was non-dialyzable and contained galactofuranosyl, glucosyl, phosphoryl, amino acyl and variable quantities of uronosyl residues. The lack of detectable quantities of mannosyl residues in this material suggests that the galactofuranosyl-containing cell wall polymer is distinct from the peptidophosphogalactomannan which is obtained from culture filtrates of P. charlesii (Gander etal., (1974) J. Biol. Chem. 249, 2063).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号