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121.
GV Donchenko IuD Kholodova IV Kuz'menko EP Klimenko 《Canadian Metallurgical Quarterly》1998,70(2):37-45
The effect of alpha-tocopherol and its derivatives on viability and growth of attached cells culture: human epithelioid carcinoma of cervix HeLa-S3K and human cervical carcinoma cell line C-4-1 according to protein content and level of alkaline phosphatase, as well to unattached cells: human acute leukemia cell cultures CEM-C-1 and CEM-C-7 according to the amount of viable cells in suspension has been studied. It has been shown that alpha-tocopherol acetate and tocopherol maintain the viability of cells, while the derivatives of tocopherol with shorted side chain considerably inhibit growth of researched cultures, alpha-tocopherol with lacking side chain being most active among them. 相似文献
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RB A?sina NF Kazanskaia EV Lukasheva IV Berezin 《Canadian Metallurgical Quarterly》1976,41(9):1656-1661
A method of microencapsulating of the proteolytic enzyme alpha-chymotrypsin into semi-permeable nylon membranes is worked out. The membrane is a polimer of 1,6-hexamethylenediamine and sebacoyl chloride. alpha-Chymotrypsin is enclosed into the capsule together with polyethyleneimine, capable of joining the walls of microcapsules and making the membrane more stable. The optimal concentrations of polyenthyleneimine and alpha-chymotrypsin are 5% and 1% correspondingly. The highest yield of microencapsulated enzyme was obtained for completely acetylated delta-chymotrypsin. The kinetic properties of microencapsulated alpha-chymotrypsin change very slightly as compared to those of the native one. 相似文献
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The authors present a survey of the Soviet and foreign literature and findings of their own experimental studies. On the basis of these data the pathologo-anatomic picture of listerosis in laboratory animals (white mice, guinea-pigs and rabbits) is given in dynamics and histogenesis of focal changes in this disease in elucidated. The most typical feature of listerosis in animals is lesions of the kidney where focal changes in the form of granulems could be detected macroscopically at an early period and with great consistency. Several stages in its histogenesis may be discerned: I. focal necroses of hepatic cells associated with their invasion with lister Listeria; 2. appearance of cellular elements around the foci of necroses with subsequent formation of granulemas consisting mainly of leucocytes and lymphoid cells; 3. development of necrobiotic changes in the central areas of granulemas with concomitance of exudative processes; 4. organization of necrotic foci with subsequent scarring. 相似文献
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MacLennan A. John; Drugan Robert C.; Hyson Richard L.; Maier Steven F.; Madden John IV; Barchas Jack D. 《Canadian Metallurgical Quarterly》1982,96(6):904
Previous studies indicate that inescapably shocked rats perform poorly on a 2-way shuttlebox escape task 24 hrs after shock. Because inescapably shocked rats become analgesic upon reexposure to a small amount of shock 24 hrs after inescapable shock (IS), they are likely to be analgesic during the shuttlebox escape task. Ss receiving an equivalent amount of escapable shock display neither the escape deficit nor the analgesia. Both the analgesia and the escape deficit respond in a similar fashion to the manipulation of a variety of other variables. These findings have led to the suggestion that the analgesia (long-term analgesia) may cause the IS-produced escape deficit. However, the present 2 experiments with 72 male albino rats demonstrated that 2 pituitary manipulations that completely eliminate the analgesia have no effect on the escape deficit. Both hypophysectomy and dexamethasone administration blocked the analgesic consequences of IS but did not reduce the magnitude of the escape deficit. Therefore, the long-term analgesia produced by IS does not cause the deficit in shuttlebox escape performance displayed by inescapably shocked rats. Results indicate that the pituitary is not essential in the production of this escape deficit. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献