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861.
Marine Biotechnology - The determination of sex in salmonid fishes is controlled by genetic mechanisms, with males being the heterogametic sex. The master sex-determining gene, the sexually...  相似文献   
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Plasmonics - A new design of graphene-based plasmonic waveguide is presented and its transmission properties are studied. The transmission channel is such designed that the chemical potential of...  相似文献   
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Follicular fluid (FF) is essential for developing ovarian follicles. Besides the oocytes, FF has abundant undifferentiated somatic cells containing stem cell properties, which are discarded in daily medical procedures. Earlier studies have shown that FF cells could differentiate into primordial germ cells via forming embryoid bodies, which produced oocyte-like cells (OLC). This study aimed at isolating mesenchymal stem cells (MSC) from FF and evaluating the impacts of bone morphogenetic protein 15 (BMP15) on the differentiation of these cells into OLCs. Human FF-derived cells were collected from 78 women in the assisted fertilization program and cultured in human recombinant BMP15 medium for 21 days. Real-time polymerase chain reaction and immunocytochemistry staining characterized MSCs and OLCs. MSCs expressed germline stem cell (GSC) markers, such as OCT4 and Nanog. In the control group, after 15 days, OLCs were formed and expressed zona pellucida markers (ZP2 and ZP3), and reached 20–30 µm in diameter. Ten days after induction with BMP15, round cells developed, and the size of OLCs reached 115 µm. A decrease ranged from 0.04 to 4.5 in the expression of pluripotency and oocyte-specific markers observed in the cells cultured in a BMP15-supplemented medium. FF-derived MSCs have an innate potency to differentiate into OLCs, and BMP15 is effective in promoting the differentiation of these cells, which may give an in vitro model to examine germ cell development.  相似文献   
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This study deals with the simultaneous determination of sucrose and trehalose in olive leaf samples, with easy sample preparation step, by second derivative UV–Vis spectrophotometry and partial least squares technique. A training set consisting of 31 binary mixture solutions was applied for the construction of PLS model. The proposed procedure was successfully applied for the simultaneous determination of both carbohydrates in laboratory prepared mixtures and in real samples. The real samples were from different growth stages of olive plant. The root mean square error of prediction was determined to be 1.95 and 2.06 for sucrose and trehalose, respectively. Also, limit of detection was 0.21 ppm for sucrose and 0.26 ppm for trehalose. The proposed procedure is rapid, simple, and easy to perform which can be used for routine analysis of both carbohydrates in plant leaves.  相似文献   
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Ageing induces a great risk factor that participates in progressing various degenerative diseases morbidities. The main characteristic of ageing is the failure in maintaining homeostasis in the organs with a cellular senescence. Senescence is characterized by reduced cell growth, evade cellular death, and acquiring a senescence‐associated secretory phenotype (SASP). Mesenchymal stem cells (MSCs) are advantageous cells in regenerative medicine, exerting pleiotropic functions by producing soluble factors, such as exosomes. MSCs and their exosomes (MSCs‐Exo) kinetic are affected by ageing and other aged exosomes. Exosomes biogenesis from aged MSCs is accelerated and their exosomal cargoes, such as miRNAs, vary as compared to those of normal cells. Besides, exosomes from aged MSCs loss their regenerative potential and may negatively influence the function of recipient cells. MSCs‐Exo can improve ageing and age‐related diseases; however, the detailed mechanisms remain yet elusive. Although exosomes‐therapy may serve as a new approach to combat ageing, the translation of preclinical results to clinic needs more extensive investigation on exosomes both on their biology and related techniques. Overall, scrutiny on the effect of ageing on MSCs and vice versa is vital for designing novel therapy using MSCs with focus on the management of older individuals.  相似文献   
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Journal of Plant Research - Valeriana officinalis is a medicinal plant, a source of bioactive chemical compounds and secondary metabolites which are applied in pharmaceutical industries. The advent...  相似文献   
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