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251.
MSG1 is a 27 kDa nuclear protein that is expressed strongly in melanotic B16 melanoma cells but very weakly in amelanotic B16 cells. Transient expression of B16 cells with an expression vector for MSG1 resulted in an increase in levels of the enzyme dopachrome tautomerase but not tyrosinase, as detected by western blotting. Stable transfection of B16 melanoma cells with plasmids containing the full length MSG1 or its deletion mutants, however, generated cell lines that showed an increase in levels of tyrosinase, dopachrome tautomerase and cellular melanin when compared with control transfected cells. Our results suggest that MSG1 plays an important role in melanogenesis, by regulating the levels of the enzymes of the pigmentary system via tyrosinase and dopachrome tautomerase.  相似文献   
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Russian Journal of Marine Biology - Macroalgae are marine bioresources with a myriad of bioactive potential to treat various chronic diseases such as cancer, obesity, diabetes and coronary heart...  相似文献   
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Introduction  

Tumors lack normal drainage of secreted fluids and consequently build up tumor interstitial fluid (TIF). Unlike other bodily fluids, TIF likely contains a high proportion of tumor-specific proteins with potential as biomarkers.  相似文献   
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The genus Saraca L. (Leguminosae) is a universal panacea in herbal medicine. The present study investigates the comparative pollen morphology of four species of Saraca viz. S. asoca (Roxb.) de Wilde, S. declinata (Jack) Miq., S. indica L., and S. thaipingensis Cantley ex Prain growing in India to reveal differences of their pollen structures to aid taxonomic and evolutionary values. The detailed morphology and surface structure of pollen grains were studied and described using light microscopy and scanning electron microscopy. The pollen grains of Saraca showed isopolar, para-syncolporate, tricolporate, with radially symmetric, prolate and prolate-spheroidal structure. The surface of pollen of S. indica is rugulate with large lirae but in S. declinata, the surface is micro-rugulate to vermiculate with relatively thin lirae and that of S. thaipingensis is indistinct as the psilate surface with a frequent protuberance and fewer perforations were observed along with the gemmae like structure. Exine ornamentation helped to separate S. indica and S. asoca. Exine thickness varies from 3-4 μm. Presence of protuberance and exine thickness varies among individuals of the species spread over different locations. Present work also provides a unique palynological identity and interrelationship of these four species based on cluster analysis taking 23 pollen characters with the help of statistical method like the plotting of ternary graph. Ternary plots also helped to calculate the level of plasticity of each character in the intra- and inter-specific level.  相似文献   
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Seagrass environments, from the main coast of India, Lakshadweep and Andaman Islands, were surveyed for seagrass and marine algal composition. Extensive seagrass meadows and the maximum number of species (seven genera and 12 species) occurred along the Tamil Nadu coast. Seagrasses were observed from intertidal to subtidal regions down to 8 m depth. Thalassia hemprichii (Ehrenberg) Aschers. and Cymodocea serrulata (R. Brown) Aschers. & Magnus were the dominant seagrasses in the subtidal zones. Halophila beccarii Aschers. was restricted to the intertidal mudflats in association with mangroves. The rich growth of seagrasses along the Tamil Nadu coast and Lakshadweep can be attributed mainly to high salinity, clarity of the water and sandy substratum. One hundred species of marine algae were recorded from the seagrass environments of India.  相似文献   
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