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91.
Probenecid in single or repeated doses does not modify levels of PGF2 alpha and TXB2 in rat brain cortex. After administration of subconvulsant dose of pentamethylene tetrazole (PMT) PGF2 alpha increases sharply and rapidly declines subsequently, whereas the elevation of TXB2 is smaller but of longer duration. After probenecid pretreatment PGF2 alpha levels do not decline up to 30 minutes after the initial peak and are still elevated after 60 minutes. Levels of TXB2 tend to be reduced after pretreatment. Differences in transport process or in biosynthetic compartments for these arachidonic acid (AA) metabolites may account for the observed data. 相似文献
92.
C. Spagnuolo A. Petroni M. Blasevich C. Galli 《Prostaglandins & other lipid mediators》1979,18(2):311-315
Probenecid in single or repeated doses does not modify levels of PGF2α and TXB2 in rat brain cortex. After administration of subconvulsant dose of pentamethylene tetrazone (PMT) PGF2α increases sharply and rapidly declines subsequently, whereas the elevation of TXB2 is smaller but of longer duration. After probenecid pretreatment PGF2α levels do not decline up to 30 minutes after the initial peak and are still elevated after 60 minutes. Levels of TXB2 tend to be reduced after pretreatment. Differences in transport process or in biosynthetic compartments for these arachidonic acid (AA) metabolites may account for the observed data. 相似文献
93.
Toshichika Ohtomo Kosaku Yoshida Hiroshi Iizuka Charles L. San Clemente 《Cryobiology》1978,15(4):461-468
The relative stability of the biological properties of three encapsulated strains of Staphylococcus aureus was compared after preservation for 1 year in two different vehicles, 10% glycerol and 15% honey and at two different temperatures, ?30 and ?80 °C. A third method of preservation was by lyophilization in 10% skim-milk plus 0.1% glutamic acid and 2% honey. Comparison with control stock cultures maintained by bimonthly subcultivation on brain heart infusion (BHI) agar slants indicated that viability of the organisms was best preserved in 15% honey. When freezing and freeze-drying were compared, superiority was achieved by the latter. Quantitative activities of acid phosphatase, DNase, and coagulase remained constant in all subcultures. Also, while no loss of virulence for mice was observed with these methods, some did occur with the stock subcultures on BHI agar slants. Concerning relative salt tolerance of the strains in these preparations, the lyophilized organisms surpassed the frozen ones. However, when lyophilizing time was prolonged, yellow pigmentation corresponding to β-carotene decreased. Finally, both frozen and lyophilized organisms maintained stable characteristics of growth type in serum-soft agar. 相似文献
94.
Substrate and steric specificity of hydropyrimidine hydrase. 总被引:7,自引:0,他引:7
95.
96.
A method for the evaluation of PGF-2alpha and PGE-2 biosynthesis in rat cerebral cortex is described. Tissue slices were incubated without any added precursor for different lengths of time. The analytical procedure involves prostaglandin extraction, purification and quantitative determination by mass fragmentography. Significant amounts of both prostaglandins were synthesized. The biosynthesis reached a plateau after 30 minutes and the ratio of PGF-2alpha to PGE-2 was approximately 3. 相似文献
97.
A method for the evaluation of PGF2α and PGE2 biosynthesis in rat cerebral cortex is described. Tissue slices were incubated without any added precursor for different lengths of time. The analytical procedure involves prostaglandin extraction, purification and quantitative determination by mass fragmentography. Significant amounts of both prostaglandins were synthesized. The biosynthesis reached a plateau after 30 minutes and the ratio of PGF2α to PGE2 was approximately 3. 相似文献
98.
Since ACTH and the opioids display opposite effects on experimentally-induced seizures, cerebrospinal fluid (CSF) levels of ACTH and beta-endorphin (beta-EP) were measured in 6 children (4-8 months) affected by infantile spasms with hypsarhythmia, an idiopathic early onset encephalopathy, and in 8 age-matched controls. beta-EP levels in the patients (76.3 +/- 14.7 fmol/ml, M +/- SD) did not differ from those in controls (109.8 +/- 42.7) while babies with epileptic encephalopathy showed reduced ACTH levels in the CSF (3.8 +/- 1.5) as compared to controls (9.0 +/- 3.7, p less than 0.01). This resulted in an increased beta-EP/ACTH ratio. Another patient previously treated with ACTH showed a normal CSF level of ACTH (9.0) with a normal beta-EP/ACTH ratio while in clinical and EEG remission. These results are consistent with the hypothesis that some infantile seizures unrelated to brain injuries could originate from an ACTH deficiency at central level and/or an imbalance of neuropeptidergic pathways. 相似文献
99.
We have previously reported that treatment of CsA with aqueous HCl gives rise to the formation of a number of water-soluble compounds. Two of these were identified from their FAB-MS/MS spectra as open-chain nona- and decapeptides. We describe here the identification of two other main compounds deriving from the same treatment. Identification was rendered possible from the comparison of their FAB-MS/MS spectra with those of methyl and acetyl derivatives. The two compounds are water-soluble, open-chain undecapeptides corresponding to 1,11 seco-CsA and of 4,5 seco-isoCsA, respectively. 相似文献
100.