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71.
72.
Inhibitors from Carob (Ceratonia siliqua L.) I. Nature of the Interaction With Gibberellic Acid on Shoot Growth 总被引:3,自引:3,他引:0
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Concentrated whole extracts of the immature fruit of carob and 3 fractions derived from this extract have been shown to inhibit the gibberellic acid induced growth of pea seedlings. The inhibition can be completely reversed by increasing the amount of gibberellic acid. The inhibitors do not reduce the endogenous growth of seedlings but only that induced by gibberellic acid. One of the fractions is a newly separated one not previously reported. 相似文献
73.
Metabolism of [1-14C]glyoxylate, [1-14C]-glycollate, [1-14C]glycine and [2-14C]-glycine by homogenates of kidney and liver tissue from hyperoxaluric and control subjects 总被引:1,自引:1,他引:0
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1. The metabolism of [1-(14)C]glyoxylate to carbon dioxide, glycine, oxalate, serine, formate and glycollate was investigated in hyperoxaluric and control subjects' kidney and liver tissue in vitro. 2. Only glycine and carbon dioxide became significantly labelled with (14)C, and this was less in the hyperoxaluric patients' kidney tissue than in the control tissue. 3. Liver did not show this difference. 4. The metabolism of [1-(14)C]glycollate was also studied in the liver tissue; glyoxylate formation was demonstrated and the formation of (14)CO(2) from this substrate was likewise unimpaired in the hyperoxaluric patients' liver tissue in these experiments. 5. Glycine was not metabolized by human kidney, liver or blood cells under the conditions used. 6. These observations show that glyoxylate metabolism by the kidney is impaired in primary hyperoxaluria. 相似文献
74.
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76.
Patterns of gas flow in the upper bronchial tree 总被引:3,自引:0,他引:3
77.
78.
Effect of glucose load and of insulin on the metabolism of glucose and of palmitate in sheep 总被引:4,自引:1,他引:3
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1. Simultaneous measurements of the entry rates of palmitate and glucose have been made in Merino sheep (wethers), starved for 24hr., by using constant infusions of [9,10-(3)H(2)]palmitate and [U-(14)C]glucose. 2. The infusion of glucose into the peripheral circulation of the sheep lowered the endogenous entry of both glucose and palmitate. Since palmitate is roughly metabolically representative of the free fatty acid fraction, there was no marked change in the calories available to the sheep. 3. The infusion of insulin into either the peripheral or portal circulation increased the uptake of glucose and decreased the uptake of palmitate by the tissues of the sheep. 4. The infusion of insulin into the peripheral circulation produced a depression in glucose entry after about 80min., whereas the infusion of insulin into the portal circulation produced an almost immediate depression in glucose entry. 5. The hypoglycaemia produced gave rise to an increase in free fatty acid production followed by an increase in glucose production. 6. No direct effect of insulin on the metabolism of free fatty acids has been demonstrated by the techniques used. The effect of insulin on the metabolism of free fatty acids is apparently mediated through its effect on glucose metabolism. 相似文献
79.
Topographical distribution of ventilation in isolated lung 总被引:3,自引:0,他引:3
80.
1. Lipids were extracted from neurons isolated from the lateral vestibular nucleus of ox (Bos taurus L.) and the ganglia of Aplysia punctata Cuvier. 2. Thin-layer chromatography of ox-neuron lipid revealed three major fractions corresponding to neutral lipid, phosphatidylethanolamine and phosphatidylserine. Part of the phosphatidylethanolamine was present as the plasmalogen. 3. Aplysia-neuron lipid contained neutral lipid, phosphatidylethanolamine and phosphatidylserine. Both phospholipids appeared to be present predominantly as the plasmalogen form. 4. The fatty acids of alkali-labile lipids of ox neurons were examined by gas–liquid chromatography. The major fatty acids were oleic acid, stearic acid and palmitic acid. 相似文献