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排序方式: 共有346条查询结果,搜索用时 78 毫秒
341.
Taqi Ahmed Khan Mohd Mazid Sajid Ali Ansari Ameer Azam Aabgeena Naeem 《International journal of peptide research and therapeutics》2013,19(2):135-146
The ability of nanoparticles to influence protein folding and aggregation is interesting, not only because of the potential beneficial applications, but also the potential risks to human health and the environment. The interactions of concanavalin A (Con A) with zinc oxide nanoparticles (ZnO-NPs) were investigated by using fluorescence, fourier transform infrared spectroscopy, circular dichroism (CD) and dynamic light scattering techniques. ANS fluorescence and CD spectroscopy authenticated the formation of molten globule state of Con A after its incubation with ZnO-NPs for 36 h. Further incubation of 48 h resulted in the aggregation of unadsorbed Con A, proved by decrease in ANS fluorescence while an increase in thioflavin T fluorescence, characteristic of an aggregates. Moreover, Fourier transform-infrared spectroscopy confirmed the aggregation of unadsorbed Con A. The aggregated products were negligible genotoxic as analyzed by pUC19 plasmid degradation and comet assay. It is clear that ZnO-NPs morphology affect unadsorbed proteins structure. A better understanding of these differences will be essential to engineer fully functional nanobioconjugates and NPs which do not damage the proteins present in the biological system. 相似文献
342.
Anouch Missirian Eyal G. Frank Jess T. Gersony Jason C. Y. Wong Shahid Naeem 《Ecology and evolution》2019,9(12):6949-6958
The influence of temperature on diversity and ecosystem functioning is well studied; the converse however, that is, how biodiversity influences temperature, much less so. We manipulated freshwater algal species diversity in microbial microcosms to uncover how diversity influenced primary production, which is well documented in biodiversity research. We then also explored how visible‐spectrum absorbance and the local thermal environment responded to biodiversity change. Variations in the local thermal environment, that is, in the temperature of the immediate surroundings of a community, are known to matter not only for the rate of ecosystem processes, but also for persistence of species assemblages and the very relationship between biodiversity and ecosystem functioning. In our microcosm experiment, we found a significant positive association between algal species richness and primary production, a negative association between primary production and visible‐spectrum absorbance, and a positive association between visible‐spectrum absorbance and the response of the local thermal environment (i.e., change in thermal infrared emittance over a unit time). These findings support an indirect effect of algal diversity on the local thermal environment pointing to a hitherto unrecognized biodiversity effect in which diversity has a predictable influence on local thermal environments. 相似文献
343.
Esraa E. Shalan Said S. Soliman Ahmed A. Mahmoud Jameel M. Al-Khayri Salha M. ALshamrani Fatmah A. Safhi Areej S. Jalal Diaa Abd El-Moneim Abdallah A. Hassanin 《Phyton》2023,92(7):2183-2196
Determination of the somaclonal variation of in vitro-propagated plants is crucial to determine the appropriate
micropropagation protocol and growth regulators for commercial scale multiplication. In this research, nine multiplication media (MM) augmented with different concentrations of 6-benzyl adenine (BA), Kinetin (Kin), and
Thidiazuron (TDZ), Three rooting media (RM) supplemented with three levels of α-naphthalene acetic acid
(NAA) and three types of soil mixtures (v/v); Coco peat/Vermiculite/Sand (CVS), Peat moss/Perlite/Sand
(PPS) and Peat moss/Perlite (PP) were used in the micropropagation protocol of daylily plants. MM2 showed
the maximum shoot length and the number of leaves, while MM9 showed the maximum number of shoots.
The RM1 showed the maximum root length and the number of roots. During acclimatization, CVS, PPS, and
PP soil mixture showed similar performance except the CVS mixture showed lower performance regarding plant
height and diameter. The genetic fidelity of micropropagated plants was evaluated using Start Codon Targeted
(SCoT) Markers. Six SCoT primers amplified 51 scorable bands with an approximate range from 146 bp to
1598 bp size. Thirty one out of 51 loci were presented in the mother plants. 40 loci were polymorphic, 11 were
monomorphic and 7 were unique. The amplification patterns of the micropropagated plants demonstrated genetic integrity to the mother plant ranging from 84.32 to 47.06 and somaclonal variations ranging from 52.94 with
5 mg/l BA pathway to 15.68 with 1mg/l TDZ pathway, thus demonstrating that the homogeneity and the variation of the micropropagated plants affected by the type and the quantity of the plant growth regulator used during
multiplication subcultures. This research can be successfully used for other ornamental and medicinal plants’ bulk
multiplication, germplasm conservation, and future genetic improvement. 相似文献
344.
Syed Arif Kamal Khurs Eed A. Siddiqui S. A. Husain Muhammad Naeem N. U. Khan 《Journal of biological physics》1992,18(4):261-269
Effects of weak electromagnetic fields are considered on recently proposed covariant and generalized coupling models of global electrocortical activity. A method to calculate the ratio of components of signal velocities is given. First-order shift in frequencies is obtained in the presence of a weak, time-varying magnetic field. 相似文献
345.
Naeem M. Eesa Hanaa El-Sherif Wael M. El-Sayed 《Invertebrate reproduction & development.》2017,61(1):27-33
The sensitivity of Spodoptera littoralis second and fourth instar larvae to the heavy metals cadmium (Cd) and lead (Pb) was investigated under laboratory conditions. Both Cd and Pb, even, at very low concentrations, had relatively high toxic effects on S. littoralis larvae. Cd was more toxic to S. littoralis larvae than Pb. In addition, the mean percentage feeding deterrence (FDI%) of Cd and Pb was concentration-dependent. The nutritional indices (consumption index, growth rate, efficiency of converted ingested and digested food, and approximate digestibility) of S. littoralis second and fourth instar larvae were more affected in Cd-treatments compared with those of Pb-treatments. Therefore, the presence of such heavy metals in the environment would exert an adverse impact on S. littoralis larvae and their development. 相似文献
346.