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The invasiveness of trophoblast cells is well known, but it is not clear whether they achieve this property by being transformed to other cell types (like malignant ones) or remain benign. Trophoblasts, in culture, were studied ultrastructurally by examining the surface morphology of the cell vis-à-vis their cytoplasmic outgrowth, and the presence and/or absence of ruffling membranes, filopodia, microvilli, pinocytotic pits or bleb-like structures was observed. Results revealed formation of ruffling membranes only on the leading edge, a presence of slender filopodia and pinocytotic pits but an absence of microvilli and bleb-like structures, the characteristic features of a transformed cell. The study indicated that the trophoblast cells, in spite of being invasive, do not convert to any other cell type. 相似文献
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Genetic evidence for distinct catalytic and regulatory subunits in yeast phosphofructokinase 总被引:2,自引:0,他引:2
Rat liver mitochondria contain an ATP-dependent proteolytic system which is localized on the outside of the inner membrane. It is capable of utilizating both the ATP produced within the mitochondria as well as that supplied externally. The system is dependent on Ca2+. Its physiological function is seen in the normal breakdown of mitochondria during their turnover. The system may be selective for the breakdown of the inner membranes. 相似文献
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Pongamia pinnata, commercially important tree species used to produce biofuels, is known for its multipurpose benefits and its role in agro-forestry.
Present study examines the amenability of vegetative propagation and effect of maturation in candidate plus tree P. pinnata through rooting of stem cuttings treated with varying concentrations and combinations of auxins. The performance of the cuttings
was evaluated using SAS GLM software and the data were analyzed as a one-way classified data with and without sub sampling
for inferring auxin concentration that can be included in programmes aimed at genetic improvement of the tree species. All
auxin treatments promoted sprouting and at lower concentrations triggered/enhanced rooting of cuttings. The effectiveness
was in the order of IBA > NAA > IAA when applied singly. IBA at 4.92 mM was found to be most effective where rooting percentage
and number of roots were significantly higher (P < 0.01) than in control. However higher concentrations of auxins above 7 mM in general inhibited the rooting of cuttings.
The interaction among auxins was found to be effective in root induction and differentiation and the most stimulating effects
were observed in three-component mixture. The effect of other cutting characteristics such as juvenility and cutting position
on rooting is also discussed. 相似文献
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Jayashree Shanker Ganapathy Perumal Arindam Maitra Veena S. Rao B. K. Natesha Shibu John Sridhar Hebbagodi Vijay V. Kakkar 《Journal of genetics》2009,88(3):291-297
Elevated factor VII (FVII) level is a risk factor for coronary artery disease (CAD). We investigated the role of R353Q polymorphism
in the F7 gene in 139 Indian families with CAD, comprising of 222 affected subjects, 105 unaffected subjects and 126 affected sibling
pairs. Plasma per cent FVIIc activity (FVII.c activity) differed significantly across R353Q genotype (P < 0.0001). Frequency of subjects with RR and QQ genotypes were higher in 4th quartile and 1st quartile of FVII.c activity,
respectively (P < 0.0001). F7 R353Q SNP was able to explain up to 7% of variation in FVII.c activity by regression analysis and an additive genetic component
of variance of 28.04% by heritability analysis. Quantitative trait loci analysis showed suggestive linkage evidence of F7 SNP with per cent FVII.c activity (LOD score −1.82; P = 0.002). Individuals with RR and RQ genotypes carried an OR of 2.071 (95% c.i. = 1.506−2.850) and 2.472 (95% c.i. = 1.679−3.641),
respectively, towards CAD risk. There was significant correlation of FVII.c activity with lipid markers, particularly among
those with RR and RQ genotype after covariate adjustment. In conclusion, the F7 R353Q SNP appears to moderately influence plasma FVII.c activity and risk of CAD in Indians. 相似文献