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731.
732.
Jennifer?R. Gruhn Nasser Al-Asmar Rachael Fasnacht Heather Maylor-Hagen Vanessa Peinado Carmen Rubio Karl?W. Broman Patricia?A. Hunt Terry Hassold 《American journal of human genetics》2016,98(1):102-115
Meiotic recombination is initiated by programmed double strand breaks (DSBs), only a small subset of which are resolved into crossovers (COs). The mechanism determining the location of these COs is not well understood. Studies in plants, fungi, and insects indicate that the same genomic regions are involved in synaptic initiation and COs, suggesting that early homolog alignment is correlated with the eventual resolution of DSBs as COs. It is generally assumed that this relationship extends to mammals, but little effort has been made to test this idea. Accordingly, we conducted an analysis of synaptic initiation sites (SISs) and COs in human and mouse spermatocytes and oocytes. In contrast to our expectation, we observed remarkable sex- and species-specific differences, including pronounced differences between human males and females in both the number and chromosomal location of SISs. Further, the combined data from our studies in mice and humans suggest that the relationship between SISs and COs in mammals is a complex one that is not dictated by the sites of synaptic initiation as reported in other organisms, although it is clearly influenced by them. 相似文献
733.
Somayeh F. Rastegar Nasser L. Hadipour Mohammad Bigdeli Tabar Hamed Soleymanabadi 《Journal of molecular modeling》2013,19(9):3733-3740
The ability of pristine graphene (PG) and Al-doped graphene (AlG) to detect toxic acrolein (C3H4O) was investigated by using density functional calculations. It was found that C3H4O molecule can be adsorbed on the PG and AlG with adsorption energies about ?50.43 and – v30.92 kcal mol?1 corresponding to the most stable configurations, respectively. Despite the fact that interaction of C3H4O has no obvious effects on the of electronic properties of PG, the interaction between C3H4O and AlG can induce significant changes in the HOMO/LUMO energy gap of the sheet, altering its electrical conductivity which is beneficial to sensor designing. Thus, the AlG may be sensitive in the presence of C3H4O molecule and might be used in its sensor devices. Also, applying an external electric filed in an appropriate orientation (almost stronger than 0.01 a.u.) can energetically facilitate the adsorption of C3H4O molecule on the AlG. 相似文献
734.
Parvaiz Ahmad Mohammad Abass Ahanger Mohammed Nasser Alyemeni Leonard Wijaya Dilfuza Egamberdieva Renu Bhardwaj 《Journal of Plant Interactions》2017,12(1):429-437
This study examined the protective effect of Zn on salt-stressed Brassica juncea plants using some key morphological and biochemical attributes at different developmental stages (30, 60, and 90 days after treatment [DAT]). Salt stress (200?mM) caused suppression in plant height, root length, and dry weight by 58.35%, 41.15%, and 53.33%, respectively, at 90 DAT, but Zn application improved these variables by 15.52%, 16.59%, and 11.45%, respectively. Furthermore, 200?mM NaCl decreased total chlorophyll by 45.32% and relative water content by 27.62% at 90 DAT, whereas Zn application compensated the decrease in the levels of both variables. NaCl (200?mM) increased H2O2, malondialdehyde, and electrolyte leakage by 70.48%, 35.25%, and 68.39%, respectively, at 90 DAT, but Zn supplementation appreciably reduced these variables. Except for catalase, enzymatic antioxidant activity increased under NaCl stress. Zn application with salt further increased the activities of superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, and glutathione-S-transferase by 33.51%, 9.21%, 10.98%, 17.46%, and 12.87%, respectively, at 90 DAT. At 90 DAT, salt stress increased flavonoids by 24.88%, and Zn supply by a further 7.68%. Overall, Zn mitigated the adverse effects of salt stress through osmotic adjustment, as well as by modulating the oxidative defense system and flavonoid contents. 相似文献