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461.
Iranian livestock diversity is still largely unexplored, in spite of the interest in the populations historically reared in this country located near the Fertile Crescent, a major livestock domestication centre. In this investigation, the genetic diversity and differentiation of 10 Iranian indigenous fat‐tailed sheep breeds were investigated using 18 microsatellite markers. Iranian breeds were found to host a high level of diversity. This conclusion is substantiated by the large number of alleles observed across loci (average 13.83, range 7–22) and by the high within‐breed expected heterozygosity (average 0.75, range 0.72–0.76). Iranian sheep have a low level of genetic differentiation, as indicated by the analysis of molecular variance, which allocated a very small proportion (1.67%) of total variation to the between‐population component, and by the small fixation index (FST = 0.02). Both Bayesian clustering and principal coordinates analysis revealed the absence of a detectable genetic structure. Also, no isolation by distance was observed through comparison of genetic and geographical distances. In spite of high within‐breed variation, signatures of inbreeding were detected by the FIS indices, which were positive in all and statistically significant in three breeds. Possible factors explaining the patterns observed, such as considerable gene flow and inbreeding probably due to anthropogenic activities in the light of population management and conservation programmes, are discussed.  相似文献   
462.
In this review, we discuss Nanotechnology models, which have been developed recently in cancer treatment. Nanotechnology manipulates matter at the atomic and molecular scale to create materials with new and advanced properties. Nano-biotechnology consists of the branches of nanotechnology that have been applied in biology (molecular and cellular genetics) and biotechnology. Nano-biotechnology allows us to put components and compounds into cells and build new materials using new methods like assembly. Cancer is a disease caused by an uncontrolled division of abnormal cells in a part of the body. Its therapeutic methods include chemotherapy, radiation, or surgery, but the effects of these techniques are not only on tumor tissue and may affect healthy tissues. Nano-Biotech applications regarding cancer include drug delivery, treatment, and foresight therapy. This review article aims to obtain a proper mentality of the current technologies of Nano-biotechnology for cancer treatment.  相似文献   
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464.
Extracellular vesicles (EVs) either as endocytic or plasma membrane-emerged vesicles play pivotal role in cell-to-cell communication. Due to the bioactive molecules transformation, lymphoma cell-derived vesicles can alter a recipient cell's function and contribute to signal transduction and drug resistance. These vesicles by acting not only in tumor cells but also in tumor-associated cells have important roles in tumor growth and invasion. On the other hand, the total protein level of circulating exosomes reveals the disease stage, tumor burden, response to therapy, and survival. In residual disease, leukemic blasts are undetectable in the bone marrow by conventional methods but exosomal proteins are elevated significantly. In this manner, new methods for measuring exosomes and exosomal components are required. In this review, we try to reveal the concealed role of EVs in hematological malignancies besides therapeutic potentials.  相似文献   
465.
Variation is key to the adaptability of species and their ability to survive changes to the Earth''s climate and habitats. Plasticity in movement strategies allows a species to better track spatial dynamics of habitat quality. We describe the mechanisms that shape the movement of a long-distance migrant bird (turkey vulture, Cathartes aura) across two continents using satellite tracking coupled with remote-sensing science. Using nearly 10 years of data from 24 satellite-tracked vultures in four distinct populations, we describe an enormous amount of variation in their movement patterns. We related vulture movement to environmental conditions and found important correlations explaining how far they need to move to find food (indexed by the Normalized Difference Vegetation Index) and how fast they can move based on the prevalence of thermals and temperature. We conclude that the extensive variability in the movement ecology of turkey vultures, facilitated by their energetically efficient thermal soaring, suggests that this species is likely to do well across periods of modest climate change. The large scale and sample sizes needed for such analysis in a widespread migrant emphasizes the need for integrated and collaborative efforts to obtain tracking data and for policies, tools and open datasets to encourage such collaborations and data sharing.  相似文献   
466.
Increasing concerns about biosafety of nanoparticles (NPs) has raised the need for detailed knowledge of NP interactions with biological molecules especially proteins. Herein, the concentration-dependent effect of magnetic NPs (MNPs) on bovine serum albumin and hen egg white lysozyme was explored. The X-ray diffraction patterns, zeta potential, and dynamic light scattering measurements together with scanning electron microscopy images were employed to characterize MNPs synthesized through coprecipitation method. Then, we studied the behavior of two model proteins with different surface charges and structural properties on interaction with Fe3O4. A thorough investigation of protein–MNP interaction by the help of intrinsic fluorescence at different experimental conditions revealed that affinity of proteins for MNPs is strongly affected by the similarity of protein and MNP surface charges. MNPs exerted structure-making kosmotropic effect on both proteins under a concentration threshold; however, binding strength was found to determine the extent of stabilizing effect as well as magnitude of the concentration threshold. Circular dichroism spectra showed that proteins with less resistance to conformational deformations are more prone to secondary structure changes upon adsorption on MNPs. By screening thermal aggregation of proteins in the presence of Fe3O4, it was also found that like chemical stability, thermal stability is influenced to a higher extent in more strongly bound proteins. Overall, this report not only provides an integrated picture of protein–MNP interaction but also sheds light on the molecular mechanism underling this process.  相似文献   
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