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991.
K B Choo K Y Chong H F Chou L N Liew C C Liou 《Biochemical and biophysical research communications》1989,158(1):334-340
The structure of the c-myc oncogene in 17 cervical tumors and patient-matched nontumor tissues from Chinese patients residing in Taiwan was analysed. In contrast to recent reports on Mexican patients, none of the samples showed rearrangements and sequence amplification in the c-myc gene. The discrepancy may be explained by different carcinogenesis mechanisms being in operation in different geographic regions. Although no structural alterations in the c-myc gene were found in seven cervical carcinoma cell lines analysed, Northern blot analysis indicated different levels of c-myc gene expression which may be related to the presence of human papillomavirus (HPV) sequence in the cell and suggests a possible c-myc-hpv interaction in some stages of the transformation process. 相似文献
992.
Production of vanillic acid from vanillin by resting cells of Serratia marcescens. 总被引:2,自引:2,他引:0 下载免费PDF全文
Resting-cell suspensions of Serratia marcescens were able to convert, quantitatively, 0.3% vanillin to vanillic acid. The vanillic acid-producing activity reached a maximum after 28 h of incubation with 0.01% vanillin as an inducer. 相似文献
993.
V I Frolenko V A Isabaeva G A Zakharov G I Gorokhova N P Novikova 《Biulleten' eksperimental'no? biologii i meditsiny》1989,108(12):663-666
During the long term noradrenaline injection (0.56 microgram/kg/min-2 hours during six days) the number of connective tissue mast cells decreases in dogs. Mature cells disappears and the percentage of young forms increases. Marked degranulation develops. 5-10 cell groups and chains are formed. The increase of free heparin level and the activation of anticoagulant unit hemostasis correspond to these changes. It is due to mast cells discharge of biologically active heparin which is an unspecific adaptogen. 相似文献
994.
A D Antipov V A Tiurin N F Avrova A E Khovanskikh V E Kagan 《Biulleten' eksperimental'no? biologii i meditsiny》1989,107(2):169-171
The protective effects of alpha-tocopherol, carnosine and their mixtures on monoamine oxidase activity, accumulation of lipid peroxidation products, lipid fatty acid composition, hydrophobicity and microviscosity of synaptic membranes during lipid peroxidation were studied. It was shown that the protective efficiency is more higher when the mixture of water and liposoluble antioxidants was used. 相似文献
995.
M N Korotkova V A Taranov V Ia Arion L N Podiukov 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1989,(6):52-57
The action of T-activin on peritoneal macrophages of CBA mice after its introduction into the animals has been studied. In intact mice the phagocytic activity of macrophages and their resistance to the cytopathogenic action of Salmonella typhimurium live cells remains unchanged. The injection of corpuscular pertussis vaccine into mice leads to a decrease in the resistance of macrophages to the action of salmonellae. The simultaneous injection of T-activin into mice in doses of 0.1 and 1.0 microgram per animal abolishes the damaging action of the vaccine. The analysis of the in vitro action of T-activin on macrophages of intact mice revealed that the preliminary incubation of cells with the preparation sharply increases their resistance to the action of salmonellae, while its introduction simultaneously with bacteria or after them rapidly leads to the death of macrophages. The action of T-activin is supposed to be linked with triggering the biosynthetic processes mediating the resistance of macrophages to the cytopathogenic action of salmonellae. 相似文献
996.
997.
998.
A relatively simple kinetic model is proposed to account simultaneously for data on the binding of carbamyl phosphate and succinate to aspartate trans carbamylase (ATCase), and for the relaxation spectrum associated with this binding. The model also accounts for measurements of the initial velocity of the reaction of ATCase with respect to aspartate and carbamyl phosphate. The principal assumption made is that ATCase consists of three identical noninteracting cooperative dimers. Ordered binding and both sequential and concerted conformational changes in the dimers are needed to account for the properties of ATCase. The values of the parameters of this model can be determined by fitting to existing experimental evidence. Various new quantitative predictions are made that can serve as additional tests of the proposed theory. 相似文献
999.
Z discs were isolated from Lethocerus flight muscle by removing the contractile proteins from myofibrils with a solution of high ionic strength. The protein composition of the Z discs was analysed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis; the major proteins were alpha-actinin, actin and tropomyosin. Z lines were selectively removed from intact myofibrils by digestion with crude lipase and chymotrypsin, but not by purified lipase. 相似文献
1000.
N P Kuleshov 《T?Sitologii?a i genetika》1978,12(1):57-63
According to the cytogenetic studies chromosome anomalies frequency in 209 children who died in the perinatal period was 7.2 per cent. These cases were found to consist of 8 autosome trisomies, 5 anomalies in sex chromosome system, 1 case of triploidy and 1 case of structural reorganization. Accounting for the elimination of chromosome anomalies during the early periods of fetus development, the frequency of chromosome lethals was shown to be 6.44 X 10(-2) in registered pregnancies and 54.89 X 10-2 in conceptions. 相似文献