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91.
The symbiotic biological N2fixation by Acacia senegal was estimated using the 15N natural abundance (δ 15N) procedure on eight provenances collected from different environments and soil types grown in a clay soil in the Blue Nile region, Sudan. Balanites aegyptiaca (a non-legume) was used as a non-N2-fixing reference plant to allow 15N-based estimates of the proportion of the Acacia N derived from atmospheric N2 (Ndfa) to be calculated. Results show variation in leaf δ 15N between A. senegal and the reference plant and among years. The relative δ 15N values (‰) were higher in B. aegyptiaca than in the N2-fixing acacia provenances. Provenances originally collected from clay soils fixed little N in the first year, but the amount fixed increased as the trees aged. All provenances showed a decrease in δ 15N with age. The Ndfa varied between 24% (Mazmoom provenance) and 61% (Rahad provenance) 4 years after planting. There was no significant difference in δ 15N between provenance groups based on soil type or rainfall at original growing site. The amount of Ndfa increased significantly with age in all provenances. The above-ground contribution of fixed N to foliage growth in a 4-year-old A. senegal was highest in the Rahad sand–soil provenance (46.7 kg N ha−1) and lowest in the Mazmoom clay-soil provenance (28.7 kg N ha−1). Our study represents the first use of the δ 15N method for estimating the N input by A. senegal to the clay plain soils of the gum belt in the Sudan.  相似文献   
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93.
Pituitary adenoma in a rabbitA 44-mo-old, female, nulliparous New Zealand White Rabbit (Oryctolagus cuniculus) presented with bilaterally diffusely enlarged mammary glands with enlarged, discolored teats that exuded brown, mucoid discharge. The complete blood count and serum chemistry panels were within normal limits, bacteria were not isolated from a culture of the discharge, and the clinical signs did not resolve with antibiotic treatment. Computed tomography and serum prolactin levels supported the diagnosis of mammary gland dysplasia, possibly due to a prolactin-secreting pituitary adenoma. Histologic evaluation confirmed the presence of a pituitary adenoma, mammary hyperplasia, dysplasia, and cystic mammary adenocarcinoma. Immunohistochemical staining confirmed the presence of abundant prolactin secreting cells in the pituitary adenoma. This is the second report of hyperprolactinemia with mammary dysplasia in rabbits, and the first report of cystic mammary adenocarcinoma associated with a prolactin-secreting pituitary adenoma in a rabbit.  相似文献   
94.
In this study, promising candidates of six apricot genotypes were compared with our local and major cultivar (Hac?halilo?lu) based on their phenological, pomological, and biochemical characteristics. Fruit weight, stone weight, flesh firmness, flesh fruit/stone ratio, TSS (Total soluble solids), glucose, fructose, sucrose, total phenols, total antioxidant activity (FRAP and ABTS assays) and bud break, first bloom, full bloom, and harvesting date of apricot cultivar candidates were compared with cultivar Hac?halilo?lu ‘HH.’ According to the obtained results, the higher content of total phenolic compounds and total antioxidant activity was determined in the N95 genotype (96.87 µmol TE/g) fruit, whereas the ‘HH’ cultivar was characterized by the lower value (94.6 µmol TE/g) especially determined by FRAP method. Individual sugars and the soluble solids content of fruit differed between selected genotypes and ‘HH’ cultivar. Glucose, fructose, and sucrose contents were higher in all selected genotypes than in Hac?halilo?lu cultivar.  相似文献   
95.
The dioecious character of Pistacia vera L (the pistachio tree) limits its breeding capacity. Thus, early stage selection of males can save time, labor, and land. This study aimed to develop sex-linked single nucleotide polymorphism (SNP) markers, together with expressed sequence tag-derived simple sequence repeats (EST-SSRs), to determine position of the sex locus in pistachio by constructing a linkage map of its sex chromosome for the first time. Nine novel sex-linked SNP markers were successfully identified by SNaPshot minisequencing analysis of 25 SNP loci from 17 restriction site-associated DNA (RAD) reads in 309 individuals. All nine markers were heterozygous in females and homozygous in males supporting a ZW/ZZ sex determination system in pistachio. A total of 105 segregating SSRs and sex-linked markers were used to identify the sex chromosome and the position of the sex locus through analysis of a Siirt × Ba?yolu F1 population with 122 progenies. Of these 105 markers, four common and four paternal SSRs were mapped onto the sex chromosome, along with the phenotypic sex locus and sex-linked markers. The resulting consensus map had a total length of 65.19 cM. The sex locus and sex-linked SNP markers were located in the center of the chromosome at a distance of 31.86 and 31.92 cM, respectively. This study presents valuable information about the sex chromosome and sex locus position as well as novel polymorphic EST-SSRs and nine sex-linked SNP markers in pistachio.  相似文献   
96.
Raman micro-spectroscopy was used to discriminate between different types of bone cells commonly used in tissue engineering of bone, with the aim of developing a method of phenotypic identification and classification. Three types of bone cells were analysed: human primary osteoblasts (HOB), retroviral transfected human alveolar bone cells with SV40 large T antigen (SV40 AB), and osteoblast-like human osteosarcoma derived MG63 cell line. Unsupervised principal component analysis (PCA) and linear discriminant analysis (LDA) of the Raman spectra succeeded in discriminating the osteosarcoma derived MG63 cells from the non-tumour cells (HOB and SV40 AB). No significant differences were observed between the Raman spectra of the HOB and SV40 AB cells, confirming the biochemical similarities between the two cell types. Difference spectra between tumour and non-tumour cells suggested that the spectral discrimination is based on the fact that MG63 osteosarcoma derived cells are characterised by lower concentrations of nucleic acids and higher relative concentrations of proteins compared to the non-tumour bone cells. A supervised classification model (LDA) was built and showed high cross-validation sensitivity (100%) and specificity (95%) for discriminating the MG63 cells and the non-tumour cells, with 96% of the cells being correctly classified either as tumour or non-tumour derived cells. This study proves the feasibility of using Raman spectroscopy to identify in situ phenotypic differences in living cells.  相似文献   
97.
Signal transduction through the vascular endothelial growth factor (VEGF)-VEGF receptor (VEGFR) pathway has a pivotal importance in angiogenesis, and has therefore become a prime target in antitumor therapy. In search for peptides antagonizing VEGF binding to its receptors, we screened a random heptamer library displayed on phage for peptides that bind the whole VEGF165 molecule and inhibit VEGF dependent human umbilical vein endothelial cell (HUVEC) proliferation. Two selected peptides with sequences WHLPFKC and WHKPFRF were synthesized. Biacore and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis indicated that these peptides bind the VEGF homodimer in a concentration-dependent manner, with micromolar affinity, and with a 2:1 peptide: VEGF stoichiometry. They inhibited HUVEC proliferation in vitro by 77 and 55%, respectively. Taken together, our results indicate that these peptides could be potent inhibitors of angiogenesis. Furthermore, we show that the peptide-VEGF binding properties can be quantified, a prerequisite for the further optimization of binders.  相似文献   
98.
Forty-three peanut butter samples from Khartoum State, Sudan, were analyzed for aflatoxins (AFs, AFB1 + AFB2 + AFG1 + AFG2) using high performance liquid chromatography (HPLC) with fluorescence detection after extraction with methanol:water (8:1, v/v) and clean-up using chloroform. All samples were contaminated with AFs, with total AF levels ranging between 26.7 and 853 μg/kg, and a mean total AF level of 287 ± 200.5 μg/kg. The highest concentrations were found for AFB1, (28 positive samples, maximum 534 μg/kg), while AFG1 was most frequently detected (43 positive samples, maximum 401 μg/kg). AFB2 (42 positive samples, maximum 3.2 μg/kg) and AFG2 (4 positive samples, maximum 30 μg/kg) were also present in these samples. The mean AF contamination levels found in this study exceeded by far all international regulations concerning maximum levels for this group of toxins. From the data, it is concluded that the levels of AF contamination in peanut butter from the Kartoum area are quite alarming, and may pose serious health hazards to consumers. Therefore, an intervention strategy to manage AF in peanut butter is urgently needed.  相似文献   
99.
Pistachio is one of the most commercially important nut trees in the world. To characterize the genetic controls of horticultural traits and facilitate marker-assisted breeding in pistachio, we constructed an SSR-based linkage map using an interspecific F1 population derived from a cross between the cultivar “Siirt” (Pistacia vera L.) and the monoecious Pa-18 genotype of Pistacia atlantica Desf. This population was also used for the first QTL analysis in pistachio on leaf and shoot characters. In total, 1312 SSR primers were screened, and 388 loci were successfully integrated into parental linkage maps. The Siirt maternal map contained 306 markers, while the “Pa-18” paternal map included 285 markers along the 15 linkage groups. The Siirt map spanned 1410.4 cM, with an average marker distance of 4.6 cM; the Pa-18 map covered 1362.5 cM with an average marker distance of 4.8 cM. Phenotypic data were collected during the growing seasons of 2015 and 2016 for four traits: leaf length (LL), leaf width (LW), leaf length/leaf width ratio (LWR), number of leaflet pairs (NLL), and young shoot color (YSC). A total of 17 QTLs were identified in the parental maps. Four QTLs for LL and LW were located on LG2 and LG4, while four QTLs for LWR ratio on LG13 and LG14, two QTLs for NLL and two QTLs for YSC were on LG7 and LG9, respectively, with similar positions in both parental maps. The SSR markers, linkage maps, and QTLs reported here will provide a valuable resource for future molecular and genetic studies in pistachio.  相似文献   
100.
OBJECTIVE: To investigate the reported increase in the expression of the glucose transporter GLUT-1 in borderline and malignant ovarian epithelial tumors and its relationship to prognosis. STUDY DESIGN: In this study, areas in which immunohistochemical membranous staining with GLUT-1 were most evident were selected, and the proportions of GLUT-1 expression in 46 benign, 11 borderline and 42 malignant cases of ovarian epithelial tumors were determined quantitatively with a computer and Zeiss Vision KS 400 3.0 (G?ttingen, Germany) for Windows (Microsoft, Redmond, Washington, U.S.A.) image analysis. RESULTS: GLUT-1 expression was determined in all borderline tumors (11 of 11) and in 97.6% of malignant tumors (41 of 42). No GLUT-1 expression was observed in benign tumors. The intensity of GLUT-1 staining was lower in borderline tumors than in malignant cases. This was statistically significant (p = 0.005). As differentiation in malignant tumors increased, proportions of GLUT-1 expression showed a relative increase, but this difference was not statistically significant (p = 0.68). CONCLUSION: When GLUT-1 expression in borderline and malignant ovarian epithelial tumors was analyzed against prognosis, no statistically significant difference was identified. Assessment of GLUT-1 expression using the image analysis program was more reliable, with higher reproducibility than in previous studies.  相似文献   
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