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Nanofibrous poly(vinylidene fluoride) (PVDF) sheets were produced by electrospinning and grafted with oxirane groups using radiation induced grafting of glycidyl methacrylate (GMA) followed by treatment with N-methyl-D-glucamine (NMDG). The NMDG density in the nanofibers was tuned by optimization of the immobilisation reaction variables using response surface methodology (RSM). The various properties of NMDG-containing nanofibers were evaluated using Fourier-transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FESEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The NMDG-containing nanofibers were tested for boron selective removal from solutions. A maximum glucamine density yield of 2.2 mmol/g was obtained at 15 wt%, 87 oC, 64.7 min and 150 % for NMDG concentration, temperature, time and degree of grafting (DG), respectively. The applied procedure incorporating RSM was found to be highly effective in the optimization of covalently immobilised glucamine on the oxirane modified PVDF based-nanofibrous structure and in imparting an excellent combination of physico-chemical and boron retention properties. A complete boron removal was achieved in 100 mg/l boron solution adsorbent with a dosage of 0.6 g at pH 7 in 2 h time. This was accompanied by a promising reusability suitable for boron removal from solutions.  相似文献   
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Copper uptake potential of different bacterial strains isolatedfrom contaminated soil was compared. The bacterial strainidentified as Bacillus polymyxa showed maximum copperuptake capacity. An attempt was made to elucidate the site ofinteraction of Cu(II) with B. polymyxa using electronparamagnetic resonance (EPR) studies. The EPR spectra showedthat accumulated copper formed complexes with oxygen andnitrogen which may be the carboxyl groups of cell-wallpeptidoglycan and nitrogen atoms of aminosugars or structuralproteins. The absence of super hyperfine splitting in theg ⊥ region of EPR spectra of treated B. polymyxa cellsafter Cu(II) uptake indicated that copper could be coordinatedwith the oxygen atoms from carboxyl groups of peptidoglycan inthe cell walls.  相似文献   
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Summary Plant regeneration from cultured immature inflorescence segments of Eleusine coracana was obtained by direct shoot development and somatic embryogenesis. Direct development of shoots from cultured inflorescence segments occurred on MS medium supplemented with 2,4-D in combination with zeatin. Inflorescences with well developed spikelets differentiated at a low frequency (<5%) from callus cultures initiated on media supplemented with 2,4-D in combination with zeatin or coconut water or picloram + kinetin. Somatic embryogenesis was also induced in callus cultures growing on MS + picloram + kinetin at the end of four passages. Supplementation of the media with different concentrations of sucrose showed 3% sucrose as the best concentration for plant differentiation from somatic embryos. The majority of the regenerated plants showed the diploid chromosome constitution in their root tips. The regenerants were in general shorter with an increased number of tillers compared to the control.Abbreviations CW Coconut water - 2,4-D 2,4-dichloro phenoxyacetic acid - Kn Kinetin - Z Zeatin  相似文献   
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Several distinct T lymphocyte subpopulations with immunoregulatory activity have been described in a number of mammalian species. This study performed a phenotypic analysis of cells expressing regulatory T cell (Treg) markers in the peripheral blood of a cohort of 18 horses aged 6 months to 23 years, using antibodies to both intracellular and cell surface markers, including Forkhead box P3 (FOXP3), CD4, CD8, CD25, interferon gamma (IFNγ) and interleukin 10 (IL-10). In peripheral blood, a mean of 2.2 ± 0.2% CD4+ and 0.5 ± 0.1% CD8+ lymphocytes expressed FOXP3. The mean percentage of CD4+FOXP3+ cells was found to be significantly decreased in horses 15 years and older (1.5%) as compared to horses 6 years and younger (2.7%), but did not differ between females and males and ponies and horses. Activation of peripheral blood mononuclear cells by pokeweed mitogen resulted in induction of CD25 and FOXP3 expression by CD4+ cells, with peak expression noted after 48 and 72 h in culture respectively. Activated CD4+FOXP3+ cells expressed IFNγ (35% of FOXP3+ cells) or IL-10 (9% FOXP3+ cells). Cell sorting was performed to determine FOXP3 expression by CD4(+)CD25(-), CD4(+)CD25(dim) and CD4(+)CD25(high) subpopulations. Immediately following sorting, the percentage of CD4+FOXP3+ cells was higher within the CD4(+)CD25(high) population (22.7-26.3%) compared with the CD4(+)CD25(dim) (17% cells) but was similar within the CD4(+)CD25(dim) and CD4(+)CD25(high) cells after resting in IL-2 (9-14%). Fewer than 2% of cells in the CD4(+)CD25(-) population expressed FOXP3. These results demonstrate heterogeneity in equine lymphocyte subsets that express molecules associated with regulatory T cells. CD4+FOXP3+ cells are likely to represent natural Tregs, with CD4+FOXP3+IL-10+ cells representing either activated natural Tregs or inducible Tregs, and CD4+FOXP3+IFNγ+ cells likely to represent activated Th1 cells.  相似文献   
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The biochemical component which attribute pungency to black pepper (Piper nigrum) is mainly the alkaloid piperine, the aroma and flavour are attributed by components like α- and β-pinenes, sabinene, myrcene, limonene, β-caryophyllene, camphene, etc. Our study revealed that the biochemical profile varies in the leaf and berries of black pepper. Total phenols, total starch, total carbohydrate and protein content from leaves and berries of selected 26 black pepper cultivars were evaluated. The concentration of oil, oleoresin, piperine and the essential oil constituents from both leaves and berries were also compared in these cultivars. Germacrene-D and elemol were found to be the major constituents of leaf oil. β-Caryophyllene was high in berries and it showed more variability in berries compared to leaf samples. Berry oil constituents namely, pinene, sabinene, myrcene and limonene were not detected in the leaf oil. Different leaf metabolites showed cumulative direct effect on berry constituents.  相似文献   
18.
Dyes derived from natural sources have emerged as an important alternative to synthetic dyes. Therefore, there is a need for developing better solid-liquid extraction techniques for leaching natural colorants from plant materials for applications in plant research, food as well as dyeing industries. The influence of ultrasound on natural colorant extraction from different potential dye yielding plant materials has been studied in comparison with magnetic stirring process as control. The color yielding plant materials used in the present study include Green wattle bark, Marigold flowers, Pomegranate rinds, 4’o clock plant flowers and Cocks Comb flowers. Analytical studies such as UV-VIS spectrophotometry and gravimetric analysis were performed on the extract. The results indicate there is a significant 13-100% improvement in the extraction efficiency of the colorant obtained from different plant materials due to the use of ultrasound. Therefore, this methodology could be employed for extracting coloring materials from plant materials in a faster and effective manner.  相似文献   
19.
Cardamom is an important high value spice crop. Hybrid breeding is discussed for some time, but there is no information for cardamom. Eight genetically diverse cardamom lines were crossed in a diallel to evaluate the performance of hybrids and determine heterosis over mid-parent, better-parent and standard control for yield and yield components. The study was undertaken for a period of 3 years from 1988 to 2001 (Experiment I). Hybrids generally showed good overall performance for most of the characteristics compared with parents. Ten of the 56 hybrids significantly out-yielded the standard control (RR 1). Substantial mid-parent (MPH), better-parent (BPH) and standard (SH) heterosis were observed for the majority of the characteristics studied. Further evaluation of selected hybrids for yield and disease resistance during 2002–2007 (Experiment II) led to the identification of two cross combinations (CCS 1 × NKE 19 and RR 1 × NKE 12) with high yield and mosaic resistance. The study revealed that cardamom hybrids with high yield potential, desirable quality characteristics and mosaic resistance can be developed from appropriate parents through heterosis breeding. This is the first report of heterosis in cardamom for yield and yield contributing characteristics.  相似文献   
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