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171.
Summary The serum activities of aspartate aminotransferase, alanine aminotransferase, -hydroxybutyrate dehydrogenase and creatine phosphokinase have been measured in the African elephant. In general, the values were broadly comparable with those of man except that alanine aminotransferase was much lower and creatine phosphokinase higher. No variation due to age, sex, season or location was observed. 相似文献
172.
R. Tirri Anneli Siltovuori M. Harri 《Cellular and molecular life sciences : CMLS》1976,32(10):1283-1285
Summary Daily injections of phenylephrine or isoprenaline for 4 or 7 days lowered the chronotropic sensitivity of -adrenoreceptors in isolated rat atria.This study was supported by grants from the National Science Council of Finland. 相似文献
173.
W. Rittel R. Maier M. Brugger B. Kamber B. Riniker P. Sieber 《Cellular and molecular life sciences : CMLS》1976,32(2):246-248
Summary Assays of 8 synthetic analogues of human calcitonin in rats showed that their hypocalcaemic activity was drastically reduced by deletion of the C-terminal amide group, chain-shortening or opening of the disulphide ring, but unaffected or enhanced by modification of the N-terminal amino group.
II. vgl.R. Maier, B. Kamber, B. Riniker andW. Rittel, Hormon. Metab. Res.7, 511 (1975).
Die hier verwendete, abgekürzte Schreibweise für Peptide folgt den Empfehlungen der IUPAC-IUB Kommission für Biochemische Nomenklatur, J.B.C.247, 977 (1972). Weitere Abkürzungen: HCT, Human-Calcitonin; PCT, Schweinecalcitonin; Bmp, -Mercaptopropionsäure (Desaminocystein); NMet, Normethionin (S-Methylcystein); -OMe, Methylester. 相似文献
II. vgl.R. Maier, B. Kamber, B. Riniker andW. Rittel, Hormon. Metab. Res.7, 511 (1975).
Die hier verwendete, abgekürzte Schreibweise für Peptide folgt den Empfehlungen der IUPAC-IUB Kommission für Biochemische Nomenklatur, J.B.C.247, 977 (1972). Weitere Abkürzungen: HCT, Human-Calcitonin; PCT, Schweinecalcitonin; Bmp, -Mercaptopropionsäure (Desaminocystein); NMet, Normethionin (S-Methylcystein); -OMe, Methylester. 相似文献
174.
R. G. G. Andersson H. J. Arnqvist L. Lundholm 《Cellular and molecular life sciences : CMLS》1976,32(5):601-602
Summary The incorporation of leucice-14C into protein in bovine mesenteric arteries was augmented by cyclic GMP (10–3
M) and decreased by cyclic AMP (10–3
M). There was no effect of 5 AMP (10–3
M). The phosphodiesterase inhibiting drugs theophylline (10–3
M) and papaverine (5×10–5 g/ml) both decreased the leucine-14C incorporation.We are indebted to Mrs.Lena Burlin for hear assistance. Finacial support has been provided by the Swedish State Medical Research Council (No. 04X-101X-4498). 相似文献
175.
H. N. Nigg J. A. Svoboda M. J. Thompson S. R. Dutky J. N. Kaplanis W. E. Robbins 《Cellular and molecular life sciences : CMLS》1976,32(4):438-439
Summary An ecdysone 20-hydroxylase enzyme system that converts -ecdysone to 20-hydroxyecdysone was prepared from the midgut of the tobacco hornworm prepupa. This partially purified enzyme is NADPH dependent and is localized in the mitochondrial fraction of the midgut tissue. 相似文献
176.
Patricia M. Kralik Beng T. Ho H. R. Matthews 《Cellular and molecular life sciences : CMLS》1976,32(6):723-725
Summary
9 (10 mg/kg, i.p.) administered to mice immediately after withdrawal from a 3-day exposure to ethanol vapor was found to intensify withdrawal reactions. No effect was seen when
9 was administered chronically during the exposure to ethanol. 相似文献
177.
Summary - and -ecdysone were synthesized from labelled cholesterol by premolt crayfish in vivo and by their Y-organs in vitro. 相似文献
178.
Shanning DONG Long WU Nigel PATERSON Alan A. HEROD Denis R. DUGWELL Rafael KANDIYOTI 《自然科学进展(英文版)》2005,15(13):67-75
The aim of the work was to investigate the fate of injectant coal in blast furnaces and the origin of extractable materials in blast furnace carryover dusts. Two sets of samples including injectant coal and the corresponding carryover dusts from a full sized blast furnace and a pilot scale rig have been examined. The samples were extracted using 1-methyl-2-pyrrolidinone (NMP) solvent and the extracts studied by size exclusion chromatography (SEC). The blast furnace carryover dust extracts contained high molecular weight carbonaceous material, of apparent mass corresponding to 107?108 u, by polystyrene calibration. In contrast, the feed coke and char prepared in a wire mesh reactor under high temperature conditions did not give any extractable material. Meanwhile, controlled combustion experiments in a high-pressure wire mesh reactor suggest that the extent of combustion of injectant coal in the blast furnace tuyeres and raceways is limited by time of exposure and very low oxygen concentration. It is thus likely that the extractable, soot-like material in the blast furnace dust originated in tars is released by the injectant coal. Our results suggest that the unburned tars were thermally altered during the upward path within the furnace, giving rise to the formation of heavy molecular weight (soot-like) materials. 相似文献
179.
Lightning activity on the central Tibetan Plateau and its response to convective available potential energy 总被引:6,自引:0,他引:6
Lightning flash activities on the central Tibetan Plateau have been studied by using the satellite-based Lightning Imaging Sensor(LIS)database from January 1998 to July 2002.The lightning activity shows a clear diurnal variation on the central Plateau.The peak lightning activity appears at about 17:00 which is 3 h earlier than that in Jingxhou,Hubei in the same latitude belt nearby,indicating that the lightning activity is a sensitive indicator of solar heating on the Plateau.The lightning discharge is weaker on the Plateau than Jingzhou.Hubei and other low-altitude continental regions because of the lower convective available potential energy(CAPE)on the Plateau.The CAPE on the Plateau is 12 times lower than that in Jingzhou,Hubei,and 20 times lower than that in the sea-level region,such as Guangzhou and Florida.However,the sensitivity of lightning activity to CAPE changes on the Plateau is up to 30 times more sensitive than other prominent low-altitude regions. 相似文献
180.
南澳岛及其附近岛屿夏季鸟类的初步调查 总被引:4,自引:0,他引:4
作者一行于 2 0 0 1年夏季对南澳及其附近岛屿的鸟类资源状况进行了调查研究 .结果发现 ,南澳及其附近岛屿有鸟类 51种 ,隶属 1 3目 2 8科 ,其中雀形目 2 3种 ,占所发现种类的 45% ,非雀形目 2 8种 ,占 55% ;国家一、二级保护动物各一种 ,分别为 :白腹军舰鸟 (F regataandrewsi)和岩鹭 (Egretta sacra) .按鸟类的栖息和迁徙习惯划分 ,有海鸟 8种 ,湿地候鸟 2种 ,湿地留鸟 9种 ,陆地候鸟 4种 ,陆地留鸟 2 8种 .在所有鸟类中以褐翅燕鸥 (Sterna anae-thetus)为优势种 ,数量最大 ,分布最广 . 相似文献