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991.
JR Dimmock NW Hamon KW Hindmarsh AP Sellar WA Turner GH Rank AJ Robertson 《Canadian Metallurgical Quarterly》1976,65(4):538-543
Some 2-benzylidenecyclohexanones, 2,6-bis(benzylidene)cyclohexanones, and related compounds were evaluated for antitumor and cytotoxic activities; (E)-2-benzylidenecyclohexanone (Ia) was shown to have significant cytotoxic properties and a potent inhibitory effect on yeast mitochondria. After intraperitoneal injection of Ia, unchanged drug and a metabolite, tentatively identified as 2-(p-hydroxybenzyl)cyclohexanol, were found in the urine. No metabolites were found in the feces. Oral administration of Ia afforded three unidentified metabolites in the urine and three unidentified metabolites in the feces. 相似文献
992.
J Hanlon RA Burnstein HA Rubin M Kalelkar EB Brucker PF Jacques EL Koller RJ Plano PE Stamer CY Chang S Kunori GA Snow D Son D Zieminska T Kafka WA Mann A Napier J Schneps T Kitagaki S Tanaka H Yuta K Abe K Hasegawa A Yamaguchi K Tamai Y Otani H Hayano H Sagawa Y Yanokura 《Canadian Metallurgical Quarterly》1985,32(9):2441-2444
993.
The effects of exogenous prolactin and hypophysectomy were tested on Na exchange across the gills of Tilapia mossambica adapted to sea-water. Exogenous prolactin produced a 75% decrease of both total Na influx and Na efflux. Total Na influx was measured simultaneously with the drinking rate. Water ingestion stopped almost completely in prolactin-treated fish. Thus branchial net excretion flux of Na was reduced 75% by prolactin. Hypophysectomy produced a 50% inhibition of Na efflux across the gill. 相似文献
994.
995.
JK Chen WJ Jankowski JA O'Malley E Sulkowski WA Carter 《Canadian Metallurgical Quarterly》1976,19(2):425-434
The existence of two components of human leukocyte interferon has been recently reported. In the present study, the nature of this molecular heterogeneity was explored by affinity chromatography on immobilized micro- and macroligands, ion-exchange chromatography, and molecular sieving. Chromatography on a series of alkyl-agarose adsorbents shows, for the first time, the intrinsic hydrophobicity of human leukocyte interferon. Additionally, the separation of two interferon components is achieved by use of the alkyl-agarose as well as by the omega-aminoalkyl-agarose adsorbents. Clear-cut separation of the two components was also achieved by chromatography on BSA-CH-Sepharose and on DEAE-Bio Gel A. An important feature of these separations is that they do not require the use of denaturing conditions. The molecular weights of the leukocyte interferon components, as determined on Sephadex G-75, are quite similar or identical, approximately 26,000. Thus, the molecular heterogeneity of human leukocyte interferon can be attributed, at least in part, to differences in the hydrophobicity and ionic properties of its two components. 相似文献
996.
The mechanism of hydroxy fatty acid-induced secretion was investigated in perfused hamster small intestine in vivo. Sodium ricinoleate at an 8-mM concentration resulted in not only secretion of water and sodium, but an increase in intestinal clearance of inulin and a 16,000 mol wt dextran as well. A concentration of ricinoleate (2 mM) which did not affect water transport, however, did not alter intestinal permeability. Ricinoleate-induced intestinal secretion was also accompanied by increased mucosal cell exfoliation as measured by the appearance of DNA in the perfusate and by apparent injury to epithelial cell membranes as judged by measurement of sucrase activity and phospholipid in cell-free aliquots of luminal fluid. Light and electron microscopic studies demonstrated substantial mucosal architectural changes with 8 mM ricinoleate with villus shortening and injury to epithelial cells at the villus tips. In contrast, cholera enterotoxin caused marked secretion of sodium and water, presumably by a cyclic AMP mechanism, but did not alter inulin clearance or enhance DNA or sucrase appearance in the lumen. These studies suggest that at least a component of ricinoleate-induced intestinal secretion is related to structural alterations of the mucosa. 相似文献
997.
998.
WA Mason 《Canadian Metallurgical Quarterly》1975,23(1-2):113-123
The strength and specificity of attraction between male and female cagemates was compared in Saimiri and Callicebus, using paired-comparison and single-stimulus methods of testing. Results from both methods showed that the attraction to the cagemate was stronger and more specific in Callicebus than in Saimiri. Sex differences were more pronounced in Saimiri than in Callicebus. Squirrel monkey females were more strongly attracted to strangers than were males and they clearly preferred female strangers over male strangers or their male cagemates. 相似文献
999.
一种新型压电式双向无阀微泵的研制 总被引:4,自引:1,他引:4
采用氧化、光刻、腐蚀、键合等MEMS技术,研制了一种硅基压电式双向无阀微泵,泵的外形尺寸为30×14×3 mm3,泵腔体体积约10 mm3.通过大量试验测试,得到了泵压、流量与工作频率、波形、电压幅值之间的关系.当工作电压为110 V、频率为40 Hz时,微泵的正向最大泵压为120 mm水柱,频率为50-90 Hz时,最大流量70μl/min;当频率为35 Hz时,微泵的反向最大泵压为70 mm水柱,最大流量56μl/min. 相似文献
1000.
吸附EDTA活性炭的电化学再生(英文) 总被引:1,自引:0,他引:1
采用吸附饱和EDTA的活性炭作为三维电极反应器中的粒子电极,多次使用后采用电化学方法对其再生。通过对吸附饱和EDTA的活性炭和多次电解使用后的活性炭的红外光谱谱图的分析得出,EDTA被活性炭吸附后产生甘氨酸H2NCH2COOH,通过N—H键生成一种永久性占据活性炭活性点的非催化活性缔合物,导致其催化活性消失,降解效率下降。采用电解方法使活性炭再生,得出活性炭的最佳活化条件为:电流100~300mA,溶液电导率1.39mS/cm,pH值6.0~8.0,电解1h可以使活性炭恢复活性,电解后有机物的残余TOC浓度低于10mg/L(初始浓度为200mg/L)。 相似文献