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971.
报道了中国呆蓟马属团5属13种, 其中包括2新种--北京呆蓟马Anaphothrips beijingensis sp. n. 和九溪长尾蓟马 Chilothrips jiuxiensis sp. n.; 提供了中国呆蓟马属团的分属检索表及种类分布信息; 并首次在国内发现了苏丹呆蓟马Anaphothrips sudanensis Trybom的黄色雄性个体。 相似文献
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Niusha Abbasi Gamasaee Hawzheen A. Muhammad Elahe Tadayon Mahsa Ale-Ebrahim Mirsasan Mirpour Majid Sharifi 《Journal of biomolecular structure & dynamics》2020,38(12):3676-3686
AbstractNickel oxide nanoparticles (NiO NPs) have received great interests in medical and biotechnological applications. However, their adverse impacts against biological systems have not been well-explored. Herein, the influence of NiO NPs on structural changes, heme degradation and aggregation of hemoglobin (Hb) was evaluated by UV-visible (Vis) spectroscopy, circular dichroism (CD) spectroscopy, fluorescence spectroscopy, transmission electron microscopy (TEM), and molecular modeling investigations. Also, the morphological changes and expression of Bax/Bcl-2 mRNA in human lymphocyte cell exposed to NiO NPs were assayed by DAPI staining and quantitative real-time PCR (qPCR), respectively. The UV-Vis study depicted that NiO NPs resulted in the displacement of aromatic residues and heme groups and production of the pro-aggregatory species. Intrinsic and Thioflavin T (ThT) fluorescence studies revealed that NiO NPs resulted in heme degradation and amorphous aggregation of Hb, respectively, which the latter result was also confirmed by TEM study. Moreover, far UV-CD study depicted that NiO NPs lead to substantial secondary structural changes of Hb. Furthermore, near UV-CD displayed that NiO NPs cause quaternary conformational changes of Hb as well as heme displacement. Molecular modelling study also approved that NiO NPs resulted in structural alterations of Hb and heme deformation. Moreover, morphological and genotoxicity assays revealed that the DNA fragmentation and expression ratio of Bax/Bcl-2 mRNA increased in lymphocyte cells treated with NiO NPs for 24?hr. In conclusion, this study indicates that NiO NPs may affect the biological media and their applications should be limited.Communicated by Ramaswamy H. Sarma 相似文献
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Behzad Eftekhar Majid Dadmehr Saeed Ansari Mohammad Ghodsi Bashir Nazparvar Ebrahim Ketabchi 《BMC neurology》2006,6(1):22
Background
Previous studies have proposed correlation between variants of the cerebral arterial circle (also known as circle of Willis) and some cerebrovascular diseases. Differences in the incidence of these diseases in different populations have also been investigated. The study of variations in the anatomy of the cerebral arterial circle may partially explain differences in the incidence of some of the cerebrovascular diseases in different ethnic or racial groups. 相似文献974.
Majid Pakdel Heidar Raissi Mahnaz Shahabi 《Journal of biomolecular structure & dynamics》2020,38(5):1488-1498
AbstractIn order to study the interaction of the anticancer agent Doxorubicin with the single-walled carbon nanotubes with different diameters as drug delivery systems, the molecular dynamics (MD) simulations have been used. Also, for design and development of intracellular Doxorubicin drug delivery systems, a series of steered MD simulations are applied to explore the possibility of encapsulated Doxorubicin–carbon nanotube penetration through a lipid bilayer in presence and absence of Nicotine molecules at different pulling rates. Our simulation results showed that in spite of the adsorption of drug molecules on the outer sidewall of the nanotubes, the spontaneous localization of one Doxorubicin molecule into the cavity of the nanovectors with larger diameters is observed. It is found that the presence of Nicotine molecules in extracellular medium increases the required force for pulling nanotube-encapsulated drug as well as the required time for penetration process, especially at higher velocity. Also, the entering process of the Nicotine molecules into the carbon nanotube causes that the encapsulated drug molecule is fully released in the hydrophobic phase of the lipid bilayer.Communicated by Ramaswamy H. Sarma 相似文献
975.
Certain genetic variations in the human population are associated with heritable diseases, and single nucleotide polymorphisms (SNPs) represent the most common form of such differences in DNA sequence. In particular, substantial interest exists in determining whether a non-synonymous SNP (nsSNP), leading to a single residue replacement in the translated protein product, is neutral or disease-related. The nature of protein structure-function relationships suggests that nsSNP effects, either benign or leading to aberrant protein function possibly associated with disease, are dependent on relative structural changes introduced upon mutation. In this study, we characterize a representative sampling of 1790 documented neutral and disease-related human nsSNPs mapped to 243 diverse human protein structures, by quantifying environmental perturbations in the associated proteins with the use of a computational mutagenesis methodology that relies on a four-body, knowledge-based, statistical contact potential. These structural change data are used as attributes to generate a vector representation for each nsSNP, in combination with additional features reflecting sequence and structure of the corresponding protein. A trained model based on the random forest supervised classification algorithm achieves 76% cross-validation accuracy. Our classifier performs at least as well as other methods that use significantly larger datasets of nsSNPs for model training, and the novelty of our attributes differentiates the model as an orthogonal approach that can be utilized in conjunction with other techniques. A dedicated server for obtaining predictions, as well as supporting datasets and documentation, is available at http://proteins.gmu.edu/automute. 相似文献
976.
Papaver bracteatum, native to Iran and southern Russia, has been grown successfully in many countries. Research in the northwest United States has confirmed the potential for its commercial production as a source of the alkaloid thebaine. Potential for the chemical conversion of thebaine into codeine, one of man’s most widely used alkaloidal medicinal agents, is reviewed. Economic and social advantages of growing this species over opium poppy (Papaver somniferum) are discussed. The value of the seed oil for cooking and industrial use is considered. 相似文献
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