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401.
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   
402.
Interleukin 12 (IL-12) is considered as an important molecule for cancer immunotherapy with significant roles in hindering tumor activity, mostly mediated by tumor-associated macrophages and anti-angiogenic factors. Mesenchymal stem cells (MSCs) have been come out as promising carriers to increase the accumulation of drug/gene in tumor sites. As a vehicle, MSCs have various advantages, including tumor-specific propensity and migratory ability; however, they have limited transfection efficiency, compared to other cells. In this study, we introduced a novel delivery system based on poly-(amidoamine) (PAMAM) (G5) to deliver a plasmid encoding IL-12 to MSCs. Initially, 30% of the amine surface of PAMAM was substituted by 10-bromodecanoic acid. Then, the low molecular weight of protamine peptide was conjugated to PAMAM and PAMAM-alkyl with N-succinimidyl 3-(2-pyridyldithio) propionate as a linker. Physicochemical properties of this modified PAMAM were evaluated, including size and surface charge, toxicity, transfection efficiency to deliver reporter and IL-12 genes into MSCs and finally the migration potential of the engineered stem cells into cancer and normal cell lines (HepG2 and NIH/3 T3). The results showed that alkyl-peptide modified PAMAM with low toxicity had a higher potential to deliver green fluorescent protein and IL-12 genes to stem cells, than PMAMAM, PAMAM-alkyl and PAMAM-peptide. These engineered stem cells had a greater ability to migrate to cancer cells than normal cells. It can be concluded that engineered stem cells containing the IL-12 gene can be considered as an efficient cell carrier for cancer immunotherapy. Further clinical studies are needed to confirm these results.  相似文献   
403.
Journal of Plant Growth Regulation - The Fusarium crown and root rot (FCRR) pathogen Fusarium culmorum (Fc) is a hemibiotrophic pathogen, with a short biotrophic phase preceding necrotropism....  相似文献   
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Biomechanics and Modeling in Mechanobiology - Pulmonary arteries constitute a low-pressure network of vessels, often characterized as a bifurcating tree with heterogeneous vessel mechanics....  相似文献   
406.
In this study, co-delivery system was achieved via plasmid encoding TNF related apoptosis inducing ligand (pTRAIL) and doxorubicin (DOX) using carrier based on polypropylenimine (PPI) modified with 10-bromodecanoic acid. Incorporation of alkylcarboxylate chain to PPIs (G4 and G5) could improve transfection efficiency via overcoming the plasma membrane barrier of the cells and decrease cytotoxicity of PPI. Characterization of fabricated NPs revealed that PPI G5 in which 30% of primary amines were substituted by alkyl carboxylate chain (PPI G5-Alkyl 30%) has higher drug loading as compared to the other formulations. PPI G5-Alkyl 30% indicated a decreased drug release may be due to alkyl chains on the surface of PPI, which serve as an additional hindrance for drug diffusion. In vitro cytotoxicity experiments demonstrated that co-delivery system induced apoptosis of tumor cells more efficiently than each of delivery system alone. Furthermore, these results revealed that our combined delivery platform of pTRAIL and DOX using Alkyl-modified PPI G5 can significantly improve the anti-tumor activity and this strategy might develop a new therapeutic window for cancer treatment.  相似文献   
407.
Molecular Biology Reports - The elevated drug efflux by ABC transports has been considered the primary mechanism of drug resistance in cancer. Recently, non-coding RNAs, such as pseudogenes, have...  相似文献   
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