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Chemical composition, physico-chemical properties and fatty acid composition of breast and drumstick meat from capons (castrated male cockerels) fed cereals were studied. Three groups of capons were reared. One group was fed ad libitum the same commercial diet until the 4th mon of life. The last month of its life, the capons of this group were fed corn. The second and third group of capons were fed the same diet from caponization. The second group was fed mixture of corn (50%) and wheat (50%). The third group of capons was fed 2/3 corn and 1/3 mixture of corn (50%) and barley (50%). Capons were reared under free-range conditions and slaughtered at 150 d of age. Caponization was performed at 48 d. No signiifcant effects of feeding in chemical composition, pH, water holding capacity, drip and cooking losses and texture of the meat were observed. The meat of the third group (capons fed 83%corn) was more yellow and showed higher content of C18:2 than that of the other capons.  相似文献   
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Potato cyst nematodes (PCN) collected in six localities in the Leningrad region of North West Russia were identified as Globodera rostochiensis pathotype Ro1 and were used for subsequent resistance tests. Seventy‐nine accessions of cultivated and closely related wild potato species from the VIR collection in Russia were screened on resistance to G. rostochiensis pathotype Ro1 and on the presence of molecular markers for H1 and Gro1‐4 resistance genes. No associations were detected between the resistance level of diploid and tetraploid Andean and tetraploid Chilean potato landraces (indigenous cultivars) and their related wild species and their geographical distribution or presence of PCR‐based markers that are associated with the H1 and Gro1‐4 genes. At the same time, all susceptible genotypes lacked such markers. New sources of resistance were found and could be used in breeding.  相似文献   
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The growing applications of tissue engineering technologies warrant the search and development of biocompatible materials with an appropriate strength and elastic moduli. Here, we have extensively studied a collagenous membrane (GSCM) separated from the mantle of the Giant squid Dosidicus Gigas in order to test its potential applicability in regenerative medicine. To establish the composition and structure of the studied material, we analyzed the GSCM by a variety of techniques, including amino acid analysis, SDS-PAGE, and FTIR. It has been shown that collagen is a main component of the GSCM. The morphology study by different microscopic techniques from nano- to microscale revealed a peculiar packing of collagen fibers forming laminae oriented at 60–90 degrees in respect to each other, which, in turn, formed layers with the thickness of several microns (a basketweave motif). The macro- and micromechanical studies showed high values of the Young’s modulus and tensile strength. No significant cytotoxicity of the studied material was found by the cytotoxicity assay. Thus, the GSCM consists of a reinforced collagen network, has high mechanical characteristics, and is non-toxic, which makes it a good candidate for the creation of a scaffold material for tissue engineering.  相似文献   
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The adaption of photosynthesis, being a key metabolic process, plays an important role in plant resistance to air drought. In this study, the Siberian crabapple(Malus baccata L. Borkh.) in the forest-steppe zone of Transbaikalia region, Russia, was subjected to air drought stress and its photosynthesis characteristics were analyzed. The results show that air drought and sufficient soil moisture supply lead to the decrease in the total chlorophyll(Chl) content, while the ratio of Chls to carotenoids is constant in the Siberian crabapple tree. The function of photosystem II(PS-II) in the crabapple trees is characterized by a decrease in the fraction of absorbed light energy spent on the photochemical work and an increase in the proportion of non-photosynthetic thermal quenching. These changes indicate the photosynthetic down-regulation that acts as a universal photoprotective mechanism. During the midday hours, the combination of high air temperature and low air humidity leads to the decrease in the maximum photochemical quantum yield of photosystem II(Fv/Fm) and the efficiency of photosynthesis(PABS). The parameters of leaf gas exchange show the significant differences in these values between the control and experimental variants. During the morning hours, the Siberian crabapple, growing in the Irkutsk City,assimilates carbon dioxide more intensively. Due to the higher air humidity, the stomata are kept open and the necessary amount of carbon dioxide entries the sites of carboxylation. The low air humidity combined with wind in the experimental variants leads to the unreasonably high water loss in the crabapple leaves by more than 27% as compared to the control variant(Irkutsk City). However, water use efficiency in the morning hours increases during plant photosynthetic processes, i.e., 42% higher than that of control. This,apparently, is a reflection of the adaptation processes of the Siberian crabapple to the air drought and parching wind.  相似文献   
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In its physiological state, cyclic adenosine monophosphate (cAMP)-dependent protein kinase (PKA) is a tetramer that contains a regulatory (R) subunit dimer and two catalytic (C) subunits. We describe here the 2.3 angstrom structure of full-length tetrameric RIIβ(2):C(2) holoenzyme. This structure showing a dimer of dimers provides a mechanistic understanding of allosteric activation by cAMP. The heterodimers are anchored together by an interface created by the β4-β5 loop in the RIIβ subunit, which docks onto the carboxyl-terminal tail of the adjacent C subunit, thereby forcing the C subunit into a fully closed conformation in the absence of nucleotide. Diffusion of magnesium adenosine triphosphate (ATP) into these crystals trapped not ATP, but the reaction products, adenosine diphosphate and the phosphorylated RIIβ subunit. This complex has implications for the dissociation-reassociation cycling of PKA. The quaternary structure of the RIIβ tetramer differs appreciably from our model of the RIα tetramer, confirming the small-angle x-ray scattering prediction that the structures of each PKA tetramer are different.  相似文献   
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