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Desert soils are infertile, and the ability to improve them by P-fertilization is limited by the solubility of phosphate. We aimed to understand the function of phosphate solubilizing bacteria and the mechanisms behind phosphate solubilization in desert soils. Vegetated and barren desert soils, mine spoil and a fertile temperate grassland loam were sampled. Bacteria and fungi were isolated and identified, and their phosphate-solubilizing abilities were measured in vitro. The release of plant available PO4, SO4, NO3 and NH4 from desert soils did not compare with that of a grassland soil. Desert soils had substantially lower solubilization than grassland, 162 and 99–121 µg PO4-P g?1 dry soil, respectively. Phosphate-solubilizing bacteria and fungi were inhabiting the soils. Si addition increased phosphate solubilization of fungi by 50%. The isolated microbes were shown, using 31P nuclear magnetic resonance (NMR) analysis, to rapidly take-up both intracellular and extracellular phosphate during the phosphate solubilizing process. Desert soil had potentially active microbial populations that are capable to solubilize inorganic phosphorus; S and Si as the limiting factors. Acidification as the main mechanism to solubilize mineral phosphate was not as evident in our desert soils as in former studies dealing more fertile soils.  相似文献   
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Leptin is a potential satiety factor and plays an important role in both metabolism and reproduction; both leptin and its receptor (Ob‐R) have been detected in human spermatozoa, thus suggesting leptin involvement in male gamete physiology. This experiment was designed to investigate leptin receptor [the long isoform (Ob‐Rb)] mRNA in bull ejaculated spermatozoa by RT‐PCR and southern hybridization. Total RNA was isolated from ejaculated spermatozoa and purified by different methods. Although the concentrations of RNA determined by all methods (except SDS/Proteinase K, lowest amount of RNA recovery) were similar, ethidium bromide staining was only detectable in lanes containing the samples isolated by sodium dodecyl sulphate (SDS) and SDS/citric acid extraction which produced higher RNA concentration. Ob‐Rb mRNA was detected in all samples using southern hybridization after RT‐PCR; it was shown only in three of them by RT‐PCR. We may conclude that Ob‐Rb mRNA is present in bull spermatozoa and leptin perhaps exerts physiological effects, as already demonstrated in humans and pigs.  相似文献   
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Traditional apple cultivars from Bosnia and Herzegovina (B&H), potentially diverse due to specific geographic location and history of the country, represent a possible source of valuable traits for future breeding efforts and sustainable fruit growing. A total of 39 accessions, 24 traditional B&H cultivars and 15 modern international cultivars, maintained at the ex situ apple collection “Srebrenik” in Northeast Bosnia were, investigated using 10 SSR (simple sequence repeats) markers and 23 morphologic characteristics. All the used primer pairs manage to amplify clearly distinguishable and highly polymorphic SSR alleles, in average 10.4 alleles per locus. More than two different alleles per locus were detected for seven accessions (five traditional B&H cultivars and two international cultivars). Forty one unique alleles were exclusively present within the B&H cultivars, while seven unique alleles were only detected within international cultivars. The differentiation between traditional B&H and international cultivars (Fst = 0.060; P < 0.0001) was significant, also confirmed by analyses of molecular variance (AMOVA) (fCT = 0.092; P < 0.001). Cluster analyses of 39 apple accessions, based on 10 SSR loci, revealed that only two traditional B&H cultivars grouped tightly with international cultivars (Ljepocvjetka and Bobovec Jon), while the rest formed separate clusters. Multivariate analyses of variance (MANOVA), nonparametric multivariate analyses of variance (NPMANOVA) and analyses of similarity (ANOSIM) showed statistically significant difference in morphologic characteristics between traditional B&H cultivars and the international cultivars. Cluster analyses of 39 apple accessions, based on the morphologic data, displayed less differentiation between traditional and international accessions, in comparison to the cluster analyses based on molecular data. No correlation between the molecular and morphologic data set was detected using the Mantel test. Many of the morphologic characteristics which have been analyzed in this study have significant commercial importance, we can assume that unlike the microsatellites these traits have been under agronomic selection pressure.  相似文献   
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This study determined the indirect selection index of doubled haploid(DH) rice using a multivariate analysis approach to select lines adaptive to salinity stress, comprising three experiments. The first experiment involved the selection of good agronomic characters in a field experiment conducted at an experimental station in Bogor, Indonesia. The second experiment involved salinity tolerance screening through hydroponic cultures using 0 and 120 mmol/L NaCl, conducted at a greenhouse in Bogor. The third experiment involved the validation of the indirect adaptability selection index(IASI) through a field experiment in Sukra(saline area). Field experiments followed a randomized complete block design(RCBD), whereas an RCBD nested factorial design was used for the greenhouse experiment. The first and second experiments used 56 DH lines and four check varieties with three replications. In the second experiment, Pokkali and IR29 varieties were also added as tolerant and sensitive checks of salinity, respectively. The third experiment used 28 selected DH lines, Inpari 29 and one sensitive DH line. The good agronomic index(GAI) was 0.465 yield + 0.433 number of productive tillers + 0.31 number of filled grains. This generated 24 DH rice lines with good agronomic traits. The salinity tolerance index(SaTI) was developed through the average of standardized salinity tolerance score and salinity selection index based on discriminant analysis. This generated 34 DH rice lines with good salinity stress tolerance. The IASI(IASI = GAI – Sa TI) selected 28 DH rice lines adaptive to salinity stress and it was considered effective by Sukra validation.  相似文献   
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The effects of supplementation with cellulase, xylanase, pectinase, hemicellulase, glucanase, phytase and protease of microbial origin on digestibility of crude protein (CP) and dry matter (DM) of soybean meal in vitro were examined in the present study. Changes in viscosity during in vitro digestion were also examined as an index of carbohydrate digestibility. Hemicellulase and all enzyme combinations without protease showed significant improvement of CP digestibility. Cellulase, xylanase, phytase and glucanase tended to improve CP digestibility. Dry matter digestibility was improved significantly by pectinase and all enzyme combinations. Cellulase and phytase tended to improve DM digestibility. Crude protein and DM digestibilities were the highest when all the enzymes except protease were added. Protease, cellulase, pectinase, xylanase, glucanase and hemicellulase significantly reduced viscosity, while phytase had no effect on viscosity. Viscosity was increased unexpectedly when all the enzymes were added. These results strongly suggest that a combination of carbohydrases improves the CP and DM digestibility of soybean meal while protease inhibits the actions of these enzymes. The present study also suggests that viscosity is not always a good index of digestibility. Moreover, excluding the protease from commercial crude enzyme preparations may improve digestibility.  相似文献   
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It is known that different breeds of cattle display differential susceptibilities to Trypanosome congolense infections, and that N'Dama cattle remain more productive after infection than Boran cattle which are more susceptible to T. congolense. Macrophages from both breeds were cultured in vitro and the expressions of a number of cytokines and iNOS mRNA were analyzed using real time RT-PCR after stimulation with antibody-opsonized trypanosomes. No significant difference was seen between the responses of the two breeds. However, RNA levels of TNF-alpha in the IFN-gamma-primed macrophages were about 100-fold higher than those in the non-primed macrophages. A significant ten-fold decrease was seen for the anti-inflammatory cytokine IL-10. These results indicate that priming of the cells with IFN-gamma cause a serious shift toward an inflammatory response.  相似文献   
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Currently, mesenchymal stem cells (MSCs) are used in veterinary clinical applications. Bone marrow and adipose tissue are the most common sources of stem cells derived from adult animals. However, cord blood which is collected non‐invasively is an alternative source of stem cells other than bone marrow and adipose tissue. Moreover, high availability and lower immunogenicity of umbilical cord blood (UCB) haematopoietic stem cells compared to other sources of stem cell therapy such as bone marrow have made them a considerable source for cell therapy, but MSCs is not highly available in cord blood and their immunogenicity is poorly understood. In this study, the cells with spindle morphology from 7 of 9 bovine UCB samples were isolated and cultured. These mesenchymal stromal cells were successfully differentiated to osteocytes, chondrocytes and adipocytes. In addition, Oct‐4 and SH3 were determined by RT‐PCR assay. It is the first report of isolation, culture, characterization and differentiation of bovine umbilical stem cells.  相似文献   
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