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181.
E. Sokolova 《Electrochimica acta》1975,20(5):323-330
The electochemical behaviour of alcohols with different numbers of C atoms and different structure depends strongly on the number of H atoms bonded to the C atom with the OH group. All other structure properties are of less importance. This experimental observations, obtained at platinum in H2SO4, leads to a mechanism of anodic oxidation as follows: a preceding dehydrogenation is followed by chemical and/or electrochemical oxidation of the reaction products. Depending on the state of the electrode surface, the dehydrogenation occurs via adsorption or through a chemical reaction with the oxygen coverage of the electrode.The mechanism discussed is not limited to alcohols, but it can be applied to molecules of similar kind (aldehydes, formic acid, etc.) also. 相似文献
182.
Enzymatic activity of horse radish peroxidase administered to the gastrointestinal tract of adult dogs and rats was assessed. It was discovered that in adult dogs, 30% of the protein reached the distal parts of the small intestine in a non-splitted form. As early as two hours after administering horse radish peroxidase over 15% of active enzyme was detectable in the gastrointestinal tract of adult rats. 0.5% of non-splitted enzyme was found in the rat large intestine. 相似文献
183.
A miniature pig kidney cell line has been established from porcine fetuses taken aseptically by hysterectomy and maintained for more than 50 passages in Eagle's minimal essential medium containing 10% heat-inactivated newborn calf serum. Cell transfers were performed each week. Primary and serially passaged cells were found to be highly refractory to infection by Chlamydia trachomatis strains TW-3, Bour, and LGV 440L and Chlamydia psittaci strains meningopneumonitis and 6BC and insusceptible to poliovirus type 1. The cells were susceptible to vesicular stomatitis virus and herpes simplex type 1 virus. Identity of the cells was established by cytotoxicity, isozyme, and cytogenetic studies. 相似文献
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Cells of nasal placode of chick embryos were studied with thymidine H3 and autoradiography. Our results shown, that the nuclei in the nasal placode synthesize DNA in the outer zone, then migrate toward the inner zone to undergo division and subsequently return to the outer zone. 相似文献
186.
WJ Rosskopf RW Woerpel SR Yanoff EB Howard JO Britt 《Canadian Metallurgical Quarterly》1981,62(10):777-779
187.
Plasma aldosterone concentration (PAC), plasma renin concentration (PRC), plasma potassium, plasma sodium and blood pressure (BP) have been measured in 22 patients with essential hypertension before and after treatment for one month with alprenolol. PAC, PRC and BP decreased and plasma potassium increased significantly during treatment. Plasma sodium, however, was unchanged. Changes in PAC were inversely correlated to changes in plasma potassium. No relationship could be demonstrated between PAC and plasma sodium. Mean BP was inversely correlated to PAC during alprenolol treatment, but bot before treatment. No relationship was found between changes in BP and changes in PRC. The results suggest that plasma potassium is an important regulatory factor for aldosterone secretion during alprenolol treatment. Other factors, however, must have a modulating influence and since the renin- angiotensin system is not suppressed to very low values, this system is possibly the most important of these factors. It is suggested that aldosterone secretion is not of primary importance in BP regulation during alprenolol treatment. 相似文献
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