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11.
The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 μm, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05).  相似文献   
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In this research, a facile and cost effective method is presented for in-situ synthesis of cuprous oxide nanoparticles on polyester fabric along with surface modification by using one pot wet chemical method at boil. Copper sulfate (CuSO4), sodium hypophosphite (SHP) and polyvinylpyrrolidone (PVP) were used as precursor, reducing agent and stabilizer, respectively. Further, monoethanolamine (MEA) was used as pH adjustment and also modifier of polyester surface introduced amide and hydroxyl functional groups on the fabric. The images of FESEM, mapping, patterns of EDX, UV-visible absorbance spectrum, FTIR analysis and X-ray diffraction pattern confirmed the successful processing. The treated samples showed excellent antibacterial properties (100 %) toward both Staphylococcus aureus and Escherichia coli pathogen bacteria. Also, the results of cytotoxicity test proved no harmful effects on the human dermal fibroblasts for the treated sample with the lower concentration of the materials having white color with good antibacterial activities. The treated samples also indicated very good UV protection properties as well as improved wettability and mechanical properties. They are also sensitive to ammonia through immediate color change when contacted with ammonia solution. The above mentioned processing method can be used for production of polyester fabric with multifunctional properties for using in the various textile industries.  相似文献   
14.
BACKGROUND: Knowledge of antimicrobial resistance patterns in E. coli, the predominant pathogen associated with urinary tract infections (UTI) is important as a guide in selecting empirical antimicrobial therapy. METHODS: To describe the antimicrobial susceptibility of E. coli associated with UTI in a major university hospital in Tehran (Iran), seventy-six clinical isolates of E. coli were studied for susceptibility to beta-lactam antibiotics by the disc diffusion method and Minimal Inhibitory Concentrations determination. RESULTS: All isolates were resistant to ampicillin, amoxicillin and oxacillin. Resistance to the other tested antibiotics was shown to be 93.4% to cefradine, 76.3% to carbenicillin, 47.3% to cefazoline, 50% to cefalexin and 32.8% to cephalothin while 1.3% expressed resistance to cefoxitime, and 2.6% were resistant to ceftizoxime and ceftriaxone. Two isolates (2.4%) harbored extended spectrum beta-lactamases (ESBL) shown by the double disc diffusion method. Substrate hydrolysis by ultra violet spectroscopy showed that 87.4% harbored penicillinases, 9% produced cephlosporinases and 3.6% degraded both substrates. Clavulanic acid inhibited enzyme activity in 82.9%, of which 78.95% was penicillinases (group IIa) and 3.95% was cephalosporinases (group IIb) of the Bush classification system. The rest of the isolates (6.58 %) were placed in group IV beta-lactamases. No group III beta-lactamase was found, as EDTA inhibited none of the enzymes. DNA amplification by polymerase chain reaction using specific primers for ampC, TEM and SHV type beta-lactamases for all of the isolates showed that 47 organisms (60%) carried the TEM gene and 18 isolates (24%) harbored blaTEM and ampC genes. About 26% of the organisms harbored SHV type enzymes. CONCLUSION: These results indicate that E. coli can posses a variety of beta-lactamases that are responsible for beta-lactam resistance.  相似文献   
15.
The aim of this study was to compare the quality characteristics and mineral content of the fiber from male and female cashmere goats raised under different management systems. Male and female Raeini cashmere goats (<1.5 years of age, n = 48) were selected from flocks raised at a government breeding station or raised commercially under either rural or nomadic conditions. The staple length, cashmere fiber diameter, coefficient of variation for fiber diameter, percentage of cashmere in a fleece, percentage of guard hair in a fleece and cashmere tenacity averaged 4.6 ±0.1 cm, 18.0 ±0.1 m, 20.9 ± 0.4%, 66.1 ± 1.5%, 33.8 ± 1.5% and 1.8 ± 0.2 gf/tex, respectively. The sulfur, copper and zinc content of the cashmere averaged 2.8 ± 0.1%, 0.00065 ± 0.00002% and 0.01276 ± 0.00025%, respectively. Rearing method significantly affected staple length, coefficient of variation of fiber diameter, cashmere tenacity and copper content. Males had a higher coefficient of variation of fiber diameter and cashmere tenacity than females (P < 0.05).  相似文献   
16.

Soybean mosaic virus (SMV) is a member of genus Potyvirus, which causes worldwide soybean [Glycine max (L.) Merr.] yield loss and seed quality deterioration. It is of great significance to find new resistance loci and genes for cultivation of soybean variety. In the present study, a recombinant inbred line (RIL) population and a genome-wide association study (GWAS) panel, which contained 193 lines and 379 germplasms, respectively, were used for QTL mapping of resistance to SMV. Linkage mapping identified a major QTL, qSMV13, on chromosome 13, conferring resistance to SMV SC3 and SC7 strains, explaining phenotypic variations 71.21 and 76.59?%, respectively. The QTL qSMV13 was located close to the known SMV resistance loci Rsv1-h. GWAS analysis revealed five single nucleotide polymorphisms (SNPs) significantly associated with resistance to SC3 on chromosomes 2, 11, 13, 14 and 16. One of the SNP markers, ss715614844, was the right flanking marker of qSMV13. Combining linkage mapping and GWAS analysis enabled us to delimit qSMV13 in a 97.2-kb genomic region containing seven genes. A LRR-RLK protein was proposed as the candidate gene of qSMV13. These results provided selection markers and candidate genes for SMV resistance in soybean molecular breeding programs.

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17.
The genetic relationships among 41 Rosa damascena accessions from various cultivation areas of Iran and one accession from Bulgaria were analyzed using 31 RAPD (Randomly Amplified Polymorphic DNA) primers. Each primer exhibited 3–12 banding patterns for a total of 343 scorable and 184 polymorphic bands. The combination of 11 primers was found optimal for discrimination of 42 accessions with very low values of cumulative confusion probability (9.7 × 10−5); indicating that only one pair from over 10,000 distinct pairs of accessions would be indistinguishable. Unweighted pair group method cluster analysis based on similarity values revealed 10 groups at the distance of 0.85. The Bulgarian genotype grouped with the majority of the Iranian genotypes in a main cluster. Results of molecular variance analysis (AMOVA) indicated that the major proportion (65.7%) of the total genetic variation was within collecting provinces rather than between them. The wide genetic variation seen for R. damascena in Iran indicates that Iran is a center of genetic diversity for this species and that there is a promising future for the breeding.  相似文献   
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19.
Water logging and salinity often occur together because rising water table brings salt to the surface. We studied the effects of a range of low soil matric suctions (or nearly paddy condition) (2–33 kPa) and salinity (EC = 0.7–8 dS m?1 for bean and 2–20 dS m?1 for wheat) on the root respiration (Rr) in two sandy loam and clay loam soils at greenhouse condition. Results showed that the aeration porosity mainly controls Rr especially at 2 kPa matric suction. As matric suction increases, soil aeration rises and consequently the Rr reaches maximum values (7.9 μmol m?3 s?1 for bean and wheat) at 6 and 10 kPa suctions in clay loam and sandy loam soils, respectively. Using a mechanistic soil respiration model reveals that these matric suctions, h, are corresponded to the aeration porosities of 0.18 m3 m?3 in sandy loam and 0.16 m3 m?3 in clay loam soils. Bean and wheat Rr remains nearly constant at higher suctions (h > 10 kPa) in sandy loam and decreases slightly in clay loam soil. Gas diffusivity and the root surface area may explain the variation of the Rr between the sandy loam and the clay loam soils. Results showed that the salinity (EC = 6–8 dS m?1 for bean and EC = 16–20 dS m?1 for wheat) amplifies the effect of aeration stress at 2 kPa matric suction in both soils. We also observed a strong correlation between root surface area, Rs, and the Rr for all experiments. We concluded that the aeration deficit is not only major factor determining differential plant respiration under adverse stress conditions, and the salinity has a pronounced impact on differences in crop physiological responses.  相似文献   
20.
The present study was conducted to investigate the effects of fenugreek seed meal (FKSM) on growth performance, blood haematological and biochemical factors, survival and stress resistance of the common carp (2.46 ± 0.06 g) fingerlings. Four practical diets containing 0 (control), 0.5%, 1% and 1.5% FKSM were used to feed fish. Fish were fed on the tested diets at a rate of 3% of body weight for 8 weeks. Results indicated that fish fed the control diet had a significantly lower weight gain, specific growth rate and condition factor compared to the other treatments (P < 0.05). Feed conversion ratio decreased significantly in fish fed diets containing FKSM. There were no significant differences in glucose levels, red blood cell count, haematocrit and haemoglobin between treatment groups and the control group (P > 0.05). Significantly lower white blood cells count was observed in fish treatment with FKSM when compared with the control group (P < 0.05). The cholesterol level in group fed supplemented diet by 1% fenugreek significantly lower than other groups (P < 0.05). Total protein levels were significantly higher in all treatments compared to the control (P < 0.05). No mortality was recorded during the feeding trial. In salinity stress experiment, highest survival rate belong to fish fed supplemented diet by 1% fenugreek. These results indicate that FKSM can be considered as a beneficial dietary supplement for improving the growth performance and blood indices of common carp fingerling.  相似文献   
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