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91.
Robert C. Corlett M.D. Boonlaw SribyattaDaniel R. Mishell Jr. M.D. Charles BallardRobert M. Nakamura Ph.D. Ian H. Thorneycroft 《Prostaglandins & other lipid mediators》1972
The abortifacient activity of prostaglandin F2α was investigated by placing one or two 50 mg tablets of prostaglandin F2α in THAM salt into the vagina of nine women less than 4 weeks pregnant at intervals of 2 to 4 hours for a 24 hour period. Serum levels of HCG, estradiol (E2), progesterone and 17α-hydroxyprogesterone were measured by radioimmunoassay prior to starting therapy and at frequent intervals thereafter for 48 hours. All but two patients had significant side-effects, mainly diarrhea and vomiting, indicating that systemic absorption took place. Although bleeding was induced in 8 of 9 women, only 3 had complete abortions. A D&C was performed on all patients 48 hours after starting therapy. A significant fall in HCG levels was noted only in the patients who aborted. Only 3 of the 9 women had significant changes in steroid levels. A fall in progesterone and 17α-hydroxyprogesterone occurred in the 3 women who aborted and took place following the fall in HCG. Estradiol levels remained in the same range in all subjects. These findings indicate that prostaglandin F2α when administered in this vehicle and this dosage is relatively ineffective as an abortifacient. When effective, its action would appear to be due to contractions of uterine muscle and not secondarily to luteolysis. 相似文献
92.
Mycoplasma, in particular species laidlawii and gallisepticum, are found to have a very small, low frequency conductivity as would be predicted by the dielectric model for bacteria and their apparent lack of cell wall structure. Membrane capacitance values for the two organisms are both about 0.9 μF/cm2, although electron micrographs show that the membrane of M. gallisepticum is 20-40 A thicker than that of M. laidlawii. 相似文献
93.
Charles Kaminski 《Planta》1971,99(1):63-72
Summary The specific peroxidase (1.11.1.7) and phenoloxidase (1.10.3.1) activities are quantitatively measured during the life of Coleus, from germination until flowering. In most organs investigated, the peroxidase activity increases rapidly with growth while the phenoloxidase activity remains low. The latter activity is higher in root apices than in more differentiated regions of roots. From the results obtained it may be concluded that the phenoloxidase activity accompanies cellular proliferation. It is suggested that the peroxidase activity plays an indirect role in root initiation through its role in cellular differentiation.
Extrait d'une thèse de doctorat soutenue à la Faculté des Sciences de l'Université de Liège. 相似文献
Extrait d'une thèse de doctorat soutenue à la Faculté des Sciences de l'Université de Liège. 相似文献
94.
During two years of passage, several myxamoebal strains of Physarum polycephalum changed with regard to their properties in crosses and plaque morphology. These changes have been correlated with increased nuclear deoxyribonucleic acid content. 相似文献
95.
Andrew G. Smith John D. Gilbert W. Arthur Harland Charles J. W. Brooks 《The Biochemical journal》1974,139(3):793-795
Cholest-5-ene-3beta,26-diol, isolated from human brain, was further characterized by oxidation to 3-oxocholest-4-en-26-ol and to 3-oxocholest-4-en-26-oic acid. Identification was achieved by comparison (by t.l.c., g.l.c. and g.l.c.-mass spectrometry) with corresponding reference compounds derived from kryptogenin. 相似文献
96.
Liver and testis slices convert 6-N-trimethyl-lysine into 4-N-trimethylaminobutyrate and carnitine. Adipose, skeletal muscle, heart, or kidney tissues metabolize trimethyl-lysine into trimethylaminobutyrate but not into carnitine. Trimethylaminobutyrate hydroxylation, forming carnitine, occurs in liver and to a minor degree in testis. Liver is the primary site of carnitine biosynthesis in the rat. 相似文献
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Passive Electrical Properties of Microorganisms: V. Low-Frequency Dielectric Dispersion of Bacteria 总被引:2,自引:0,他引:2 下载免费PDF全文
Very high dielectric constants have been observed for bacteria at low frequencies. High dielectric constants such as these can be explained by a theory which has been developed for the low-frequency dielectric dispersion of porous charged particles and which has been tested successfully through measurements with ion exchange resins. The bacterial cell wall is electrically similar to an ion exchange resin. Observations show that the theory provides a quantitative explanation for the low-frequency dielectric dispersion of bacteria. 相似文献