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991.
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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
995.
Effect of membrane additives on vesicle fusion 总被引:1,自引:0,他引:1
A large variety of alkyl derivatives were found to either slow or block the low-temperature induced fusion of dipalmitoylphosphatidylcholine small unilamellar vesicles (DPPC SUV) when incorporated into the SUV bilayer at five mol%. Only corn oil was fusogenic. 相似文献
996.
G. K. Wallace 《Biological cybernetics》1989,61(3):233-240
The patterns of EMG activity in the biceps and triceps muscles were recorded during horizontal oscillatory movements of the forearm. Subjects showed increased frequency of oscillation as they voluntarily reduced movement amplitude. EMG burst duration was significantly correlated with wavelength of oscillation in every case. In almost half the cases burst intensity was also positively correlated with wavelength. Subjects seemed to be using one or both these methods to control amplitude. A model was developed in three stages which satisfactorily accounted for the data. 相似文献
997.
J. G. H. Roebroek S. Gagné D. G. Stavenga 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1989,165(1):75-81
Summary The photochemical cycle of the visual pigment molecules in the blowflyCalliphora erythrocephala was investigated by transmission measurements, making use of the fact that intermediate states of the visual pigment molecules each have a characteristic absorption spectrum.It is shown that the conversion of metaxanthopsin (M 580) to the native xanthopsin state (P 490) induced by an orange-red light pulse proceeds through a newly discovered intermediate (N), which thermally decays with a time constant of about 13 ms at room temperature.The absorption spectrum of N peaks in the blue-green at about 490 nm. In the green and orange N absorbs more strongly than the native xanthopsin, but in the blue N and xanthopsin absorb almost equally. The latter finding explains why N has remained undetected in earlier studies.Abbreviations
ERP
early receptor potential
-
M
metaxanthopsin
-
P
xanthopsin 相似文献
998.
Vitronectin is a cell-adhesive glycoprotein in serum and plasma, also termed serum spreading factor and complement S-protein. It consists of a mixture of a polypeptide of molecular weight 75 kilodalton (kDa) and its nicked product of 65 kDa plus 10 kDa. By a quantitative immunoblotting assay, human blood samples could be classified into three distinct vitronectin types; type I (58% of the population) was 75 kDa rich and 65 kDa poor, type II (35% of the population) contained approximately equal amounts of 75 kDa and 65 kDa, and type III (5% of the population) was 75 kDa poor and 65 kDa rich. The vitronectin type did not correlate with age, sex, or ABO blood type. 相似文献
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1000.