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981.
William A. Horton Nena Dockery David Sillence David L. Rimoin 《Biotechnic & histochemistry》1980,55(1):19-29
We have used glycol methacrylate to study undecalcified skeletal growth plate and subchondral bone. Minor modifications of the original technique including dehydration in glycol methacrylate vacuum infiltration and polymerization in the cold make it quite suitable for embedding of such tissues. Moreover, specimens can be processed quickly and the morphologic and biochemical integrity of the tissue retained so that histochemical procedures can be readily applied. Collagen, glycosaminoglycan, glycogen, lipid, calcium and the activity of alkaline and acid phosphatase were localized. This technique appears to be very useful for studying skeletal tissues. 相似文献
982.
David A. Ellwood Murray D. Mitchell Anne B.M. Anderson A.C. Turnbull 《Prostaglandins & other lipid mediators》1980,19(3)
A method of tissue superfusion has been used to measure
prostanoid production by the ovine cervix during late pregnancy and at parturition. In late pregnancy (105–135 days of gestation) cervical tissue produced relatively large amounts of prostaglandin E (PGE); in comparison, the production rates of prostaglandin F (PGF), 13, 14-dihydro-15-oxo-prostaglandin F (PGFM) and 6-oxo-prostaglandin F1α were generally low. Thromboxane B2 (TXB2) production was minimal and often unmeasurable. There were significant increases in the production rates of PGE and 6-oxo-PGF1α by cervical tissue taken immediately after delivery, when compared to late pregnancy. Mean production rates of PGE increased from 19.8 ± 4.1 to 43.8 ± 7.4 ng/g. dry wt./min; 6-oxo-PGF1α production rates increased more than three-fold from 10.0 ± 2.7 to 34.6 ± 9.8 ng/g. dry wt./min (means ± S.E.M.). There were no significant differences in the rates of production of PGF, PGFM and TXB2 by the two groups. 相似文献
983.
984.
Thirty-six attempts were made to isolate from the uterine flushings of culture positive and serologic reactor cows. Sixteen of these attempts were made after cows had been programmed for superovulation and a simultaneous attempt was made to recover eggs. Udder secretion samples for culture and blood for serology were collected at the time of the flushing procedure. In addition, a field isolate of suspended in three different solutions (one commonly used for nonsurgical embryo retrieval) was quantitated at various intervals up to 24 hours.Brucellae were not cultured from any of the uterine flushings although it was demonstrated that the organisms would remain viable in the media used for up to 24 hours. Udder secretions contained brucella at the time of flushing in 17 of the 36 attempts. Results indicated that transfer from infected donors might be achieved without transfer of infection. It is cautioned that final evidence of success would have to come after recipients had undergone serologic and cultural surveillance through their gestation period. 相似文献
985.
Campylobacter jejuni is an important cause of human diarrheal disease throughout the world and likeSalmonella enteritidis, has a large animal reservoir which includes most of man's domestic animals. Until recently, it has been difficult to trace the chain of transmission from animals to man because of inadequate environmental sampling techniques and means to distinguish strains. Recent improvements in these techniques have made environmental studies more feasible in 2 water-related out-breaks.In 1 study,C. jejuni was found to be an important cause of sporadic, summertime diarrheal disease among hikers in national wilderness areas of Wyoming. In this setting, illness was significantly associated with drinking untreated surface water. SubsequentlyC. jejuni was isolated from surface water, including mountian streams, and from animals in the area. Some of the environmental isolates were serotypically identical to strains isolated from humans.A second study occurred as a result of an outbreak of Campylobacter enteritis in a community in northern Illinois which was epidemiologically associated with the community water system.Campylobacter jejuni was isolated from several surface water sources and from the implicated water system. These studies demonstrate that environmental isolation ofC. jejuni is now possible and may add to our understanding of disease transmission. 相似文献
986.
Intact lipopolysaccharide antigens isolated from seven different immunotypes of Pseudomonas aeruginosa have been examined by 31P-NMR spectroscopy. These macromolecular complexes contain phosphorus covalently attached to the carbohydrate residues present in the lipid A moiety and the ‘core’ oligosaccharide region. The spectral signals for various ortho- and pyro-phosphoric esters were observed. All phosphate groups appeared to be mono-esterified. Certain shifts characteristic for phosphate diester groups, observed in lipopolysaccharide complexes from other Gram-negative bacteria, were absent. Furthermore, no evidence was found to indicate that phosphate groups are involved in the covalent linkage of individual lipopolysaccharide complexes to form dimers or trimers. 相似文献
987.
Intact lipopolysaccharide antigens isolated from seven different immunotypes of Pseudomonas aeruginosa have been examined by 31P-NMR spectroscopy. These macromolecular complexes contain phosphorus covalently attached to the carbohydrate residues present in the lipid A moiety and the ‘core’ oligosaccharide region. The spectral signals for various ortho- and pyro-phosphoric esters were observed. All phosphate groups appeared to be mono-esterified. Certain shifts characteristic for phosphate diester groups, observed in lipopolysaccharide complexes from other Gram-negative bacteria, were absent. Furthermore, no evidence was found to indicate that phosphate groups are involved in the covalent linkage of individual lipopolysaccharide complexes to form dimers or trimers. 相似文献
988.
David Gelmont Robert A. Stein James F. Mead 《Biochemical and biophysical research communications》1981,102(3):932-936
Vitamin E-deficient rats or rats subjected to other conditions thought to lead to peroxidation of tissue lipids produce pentane and other hydrocarbon gases in the breath. However, pentane production is found to depend on the linoleate content of the recent diet. It is decreased or eliminated by inclusion of ascorbic acid in the food or water, by removal of linoleate from the diet, by starvation and by the antibiotic, clindamycin. It is enhanced by feeding linoleate hydroperoxide or by removal of vitamin E from the diet for a short period. These findings lead to the conclusion that the major source of pentane is not membrane lipid peroxidation but is from the action of intestinal bacteria on linoleate hydroperoxide. 相似文献
989.
David C. Heimbrook Stephen G. Sligar 《Biochemical and biophysical research communications》1981,99(2):530-535
We have examined the 5--hydroxylation of camphor by cytochrome P450 in [18O] water/buffer solution. In the reaction of the reconstituted multienzyme system, no 18O-label is observed in the product alcohol. Similarly, in the m-chloroperbenzoic acid or cumene hydroperoxide supported reactions with ferric P450, solvent oxygen is not incorporated into hydroxycamphor. When the analagous reaction is carried out using iodosobenzene as the exogenous oxidant, however, the alcoholic oxygen of the product is derived entirely from the solvent. These results cannot be explained by equilibration of the iodosobenzene oxygen with solvent water before reacting with P450, and suggest a unique mechanism for iodosobenzene-supported P450 oxygenations. We propose two distinct mechanistic activities for cytochrome P450: a hydroxylase, and an oxene transferase, with the former encompassing the classic oxygenase as well as “peroxygenase” reactions. 相似文献
990.
Marie-Luise Blue David L. Williams 《Biochemical and biophysical research communications》1981,98(3):785-791
Apo II and vitellogenin were detected in sera of nonestrogenized roosters by radioimmunoassay. Tamoxifen (30mg/kg) raised basal serum apo II more than 50 fold and vitellogenin more than 15 fold. Serum accumulation of apo II was biphasic in response to increasing doses of tamoxifen. This biphasic response was reflected in the relative rates of hepatic apo II synthesis. The tamoxifen metabolites, hydroxytamoxifen and desmethyltamoxifen, and the triphenylethylene antiestrogen, CI 628, also increased serum apo II. These studies show that the expression of vitellogenin and apo II genes occurs at a basal rate prior to exogenous estrogen treatment. These experiments also demonstrate that the triphenylethylene antiestrogens have agonist activity in the chicken when very sensitive techniques are used to measure estrogen-regulated proteins. 相似文献