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Due to the importance of soluble nanotubes in biological systems, computational research on DNA base functionalized nanotubes is of interest. This study presents the quantitative results of Monte Carlo simulations of Li-doped silicon carbide nanotubes and its nucleic acid base complexes in water. Each species was first modeled by quantum mechanical calculations and then Monte Carlo simulations were applied to study their properties in aqueous solution. Solvation free energies were computed to indicate the solvation behavior of these compounds. The computations show that solvation free energies of the complexes of DNA bases with Li-doped SiC nanotubes are in the order: thymine > cytosine > adenine > guanine. The results of complexation free energies were also used to study the stability of related structures, which indicate that thymine-Li-doped SiC nanotubes produce the most stable compound among the four DNA base complexes.  相似文献   
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Combination therapy is a novel cancer therapy approach that combines two or more chemotherapy drugs. This treatment modality enhances the efficacy of chemotherapy by targeting key pathways in an additive or synergistic manner. Therefore, we investigated the efficacy of combination therapy by widely used chemotherapy drug doxorubicin (DOX) and oleanolic acid (OA) to induction of apoptosis for pancreatic cancer (PC) therapy. The effects of DOX, OA, and their combination (DOX-OA) were investigated on proliferation and viability of PC cell line (PANC-1) by MTT assay. Moreover, migration and invasion of the cancer cells were evaluated by trans-well migration assay and wound healing assay. Flow cytometry and DAPI (4′,6-diamidino-2-phenylindole) staining were employed to investigate apoptosis quantification and qualification of the treated cancer cells. Finally, mRNA expression of apoptosis-related genes was assessed by quantitative real-time polymerase chain reaction. Our results demonstrated that the proliferation and metastasis potential of PC cells significantly decreased after treatment by DOX, OA, and DOX-OA. Moreover, we observed an increase in apoptosis percentage in the treated cancer cells. The apoptosis-related gene expression was modified to increase the apoptosis rate in all of the treatment groups. However, the anticancer potency of DOX-OA combination was significantly more than that of DOX and OA treatments alone. Our study suggested that DOX-OA combination exerts more profound anticancer effects against PC cell lines than DOX or OA monotherapy. This approach may increase the efficiency of chemotherapy and reduce unintended side effects by lowering the prescribed dose of DOX.  相似文献   
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Journal of Applied Phycology - Phlorotannins are polyphenolic compounds in brown algae and can be used as a natural UV filter in sunscreen formulations. The aim of the present study was to...  相似文献   
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In the present work, the morphological characteristics of sagitta were described and analysed for 10 species of combtooth blennies (Blenniidae) inhabiting the intertidal region of the Persian Gulf and Makran zone of Oman Sea to see the taxonomic usefulness of otoliths, especially their hidden characters for species identification. Based on the obtained results, sagitta morphology could be considered as diagnostic characters distinguishing the genera Alticus, Antennablennius, Istiblennius, Omobranchus and Parablennius showing differences related to general shape, that is, elliptic/oval to triangular; shape of antirostrum and its degree of development; the degrees of convexity of ventral and dorsal margins, and shape of ostium. The common/general otolith characters shared in the all studied combtooth blennies, is the heterosulcoid condition, which is a shared character with Perciformes and Gobiiformes. The type of sulcus is ostial, and it can be considered as a plesiomorph character shared with a basal group of actinopterygian fishes. The obtained results could be useful in taxonomical, paleontological, ecological and food and feeding habits studies.  相似文献   
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