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961.
Robust estimation in the errors-in-variables model 总被引:2,自引:0,他引:2
962.
963.
964.
The blood flow rate in the utero-ovarian vein (UOV) has been measured in adult female rats during the different phases of the estrous cycle. It was observed that the blood flow rate in the UOV is high at proestrus and at estrus and low during diestrus days 1 and 2. The intravenous injection of 10 μg PGF2α or PGE2 diminishes the blood flow rate in the UOV. The efficacy of the two PGs in reducing blood flow is different in the various phases of the estrous cycle, being maximal during the day of estrus. 相似文献
965.
966.
The direct one-step synthesis of 3-(O-carboxymethyl)oximes of representative C21-4-pregnen-3,20-diones is reported. The method requires the preparation of a 3-enamine derivative which, serving as an intermediate product, is readily converted to the 3-(O-carboxymethyl)oxime upon addition of one molar equivalent of O-(carboxymethyl)hydroxylamine hemihydrochloride. The reaction appears to be generally applicable for selective 3-(O-carboxymethyl)oxime formation in steroids possessing multi-carbonyl groups, thus facilitating the coupling of steroidal haptens to protein at the C-3 position of the steroid molecule for enhanced immunospecificity. In this manner, antisera to 16α-hydroxyprogesterone and 17α-hydroxy-progesterone were obtained from immunized rabbits and specificity was established by radioimmunoassay. 相似文献
967.
Eliot Spindel Kilmer S. McCully 《Biochimica et Biophysica Acta (BBA)/General Subjects》1974,343(3):687-691
Since hemocysteinemia is associated with arteriosclerosis, the conversion of methione to homocysteine thiolactone was studied in guinea pig liver in vivo. 60 min after intraperitoneal injection of [14C]methione, [14C]homocystein thiolactone was found to constitute 9.1% ± 0.2 of the lipid bound 14C and 20% ± 1.0 of the acid soluble 14C. This conversion is the first step of a new pathway by which the sulfur of methionine is transferred to phosphoadenosine phosphosulfate. 相似文献
968.
J Martinsen M J Irwin P S Ho B M Hoffman I M Klotz 《Biochemical and biophysical research communications》1983,112(3):954-956
Electron paramagnetic resonance spectra of azidosemimethemerythrin (from Phascolopsis gouldii) have been integrated to find the total number of spins per monomer unit. The value observed, 1.0 +/- 0.1 spins per Fe2 pair, confirms the assignment of a hybrid oxidation state, FeIIFeIII, to each site. 相似文献
969.
970.
Production of prostaglandins by cells in vitro: radioimmunoassay measurement of the conversion of arachidonic acid to PGE2 and PGF2 alpha 总被引:3,自引:0,他引:3
A specific radioimmunoassay has been applied to the measurement of the conversion of arachidonic acid to PGE2 and PGF2α. PGE2 and PGF2α biosynthesis was linearly related to the amount of arachidonic acid added and was significantly inhibited by indomethacin in concentrations as low as 10?10 M. Sonicated Hela, L, and HEp-2 cells synthesized 244.0, 42.3, and 22.6 ng PGE2 per mg of protein, but made substantially less PGF2α. 相似文献