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This study was designed to examine the in vitro antimicrobial and antioxidant activities of the essential oil and various extracts obtained from aerial parts of Thymus eigii. The essential oil was particularly found to possess stronger antimicrobial activity, whereas other nonpolar extracts and subfractions showed moderate activity and polar extracts remained almost inactive. GC-MS analysis of the oil resulted in the identification of 39 compounds, representing 93.7% of the oil; thymol (30.6%), carvacrol (26.1%), and p-cymene (13.0%) were the main components. The samples were also subjected to a screening for their possible antioxidant activity by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and beta-carotene-linoleic acid assays. In the former case, the polar subfraction of the methanol extract was found to be superior to all extracts tested, only 16.8 microg/mL of which provided 50% inhibition, whereas all extracts, particularly the polar ones, seem to inhibit the oxidation of linoleic acid in the latter case. These data were further supported by total phenolics analysis, indicating that the antioxidative potential of the extracts was closely related to their phenolic constituents.  相似文献   
23.
Cell suspension cultures of various crop plants have been used for studying salt and drought stress on the GSH/GSSG-system, As already recorded for whole plants, cell cultures of different species vary in their glutathione levels. In general, cell cultures of species with relatively high glutathione content are more tolerant to abiotic stress. A high glutathione content alone is not adequate to prevent cell damage and a decrease in cell growth. E.g. the addition of sulphur to stressed cell cultures slightly enhances the GSH content but does not enhance the adaptation of these cells to stress. Thus, the role of glutathione in the adaptation of cells to stress situations seems to be only one component in a more complex response mechanism.  相似文献   
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Sultan Marsh is one of the largest and most important wetlands in Turkey, Middle East and Europe, embodying saline and fresh water ecosystems, which provide a shelter for 426 bird species. The area has begun to contribute much to the tourism of Kayseri state and its environs. However, the sites in the vicinity of the sewerage – sludge and fertilizer plants are highly damaged due to pollution. As such, studies on the heavy metal status of water, sediment and plants were investigated. Phragmites australis, Ranunculus sphaerosphermus plants and samples of sediments were taken from 13 different stations of this Marsh. All sampling sites in the study area basin were generally more or less polluted when compared with the control sites. Cr concentrations in the roots of the plants were higher than in the sediment. The tissues of Phragmites australis accumulated heavy metals more than those of Ranunculus sphaerosphermus. The heavy metal accumulation in different parts of plants followed the sequence: root > stem > leaf. Both plants can be used as biological indicators while determining environmental pressures; however, Phragmites australis proved more appropriate for such studies.  相似文献   
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The objective of the present study was to examine the effect of potassium (K) fertilization and soil texture on total yield (1st and 2nd cuttings) and yield components of sweet basil (Ocimum basilicum L.) A greenhouse pot experiment was conducted in a completely randomized statistical design. Basil growth was examined in two different textured soils under three different doses of K fertilization. Generally, for the basil grown under clay soil conditions, moderate amounts of K fertilization is proposed to be sufficient if higher linalool contents are wanted. However, if the growing conditions are sandy loam in texture, it is suggested that higher doses of K be used. Results also highlighted the contribution of second cut as an important cultural practice in the cultivation of an annual basil.  相似文献   
26.
In this study, the photocatalytic degradation of commercial azo dye (Remazol Red 133) in the presence of titanium dioxide (TiO2) suspensions as photocatalyst was investigated. The effect of various operational parameters, such as pH of dye solution and catalyst concentration on the photocatalytic degradation process, was examined. The mineralization of dye was also evaluated by measuring the chemical oxygen demand of the dye solutions. The extent of photocatalytic degradation was found to increase with increasing TiO2 concentration. For the Remazol Red dye solutions, a 120-min treatment resulted in 97.9% decolorization and 87.6% degradation at catalyst loading of 3 g/L. Experiments using real textile wastewater were also carried out. Textile wastewater degradation was enhanced at acidic conditions. The decolorization and degradation efficiencies for textile wastewater were 97.8% and 84.9% at pH 3.0, catalyst loading of 3 g/L, and treatment time of 120 min.  相似文献   
27.
In tomato, the predominant flavonoid is quercetin-3-rutinoside (rutin). In this study, we aim to investigate the phenylalanine ammonia-lyase (PAL) and the quercetin-3-O-glucosyl transferase (3-GT) reactions in the formation of rutin during tomato fruit ripening. Tomatoes of the Moneymaker variety at different development stages (green, breaker, turning, pink, red, and deep red) were divided into flesh and peel fractions. In each sample, both the content of rutin and the enzymatic activities for PAL and 3-GT were recorded. The highest activities of PAL were recorded in the peel of turning fruit (3,000 μkat/mg fresh weight). In fruit flesh, maximal activity was observed in red fruit (917.3 μkat/mg). For both tissues, PAL activity strongly decreased at the final (deep red) fruit stage. The activity of 3-GT in peel peaked in the turning fruit stage (50.7 pkat/mg), while in flesh maximal activity (33.4 pkat/mg) was observed in green fruit, which rapidly declined at the turning stage. Higher levels of rutin were detected in the tomato peel compared to the flesh part with the highest level being found at the green stage. The relation of PAL and 3-GT activities to rutin content is also evaluated.  相似文献   
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An unilocular ovary is often observed in the Fabaceae family. Thermopsis turcica Kit Tan, Vural et Küçüködük is an endemic, rare plant species in Turkey that is distinguished by its multi-carpellary apocarpous ovaries. No research has been conducted on the crossing of T. turcica with other species to date. Vicia faba L. (fababean) (2n = 12), which is one of the oldest crops used for human and animal consumption, and Thermopsis turcica (2n = 18) were selected to explore the possibility of increasing yield in edible crops by intergeneric crossing. When T. turcica was used as a male parent, pollen germination and pollen tube growth appeared to be normal and globular embryo formation was observed, but hybrid seeds aborted due to post-fertilization barriers. In contrast, in all crosses in which T. turcica was used as a maternal parent, an embryo was not obtained, and viability of the pistil did not exceed 10 days after pollination. Also, in the samples left to free pollination, pistils died in a few days after anthers were removed just before pre-anthesis. Inability to obtain viable seeds by hybridization of Vicia faba and T. turcica should not be considered as a demonstration of complete incompatibility of the species in intergeneric crosses. The present report constitutes the first study on this issue.  相似文献   
30.
Boron (B) is an essential micronutrient for plants through paticipating key reactions such as reproduction, development, and regeneration. Similar to its deficiency, its over-concentations possess toxic effects on plant growth. In this work, possible boron toxicity was researched through evaluating alaterations in antioxidant enzymes, oxidative stress biomarkers, and chlorophyll contents for two types of lentil species as red (native) and green (winter flake 11) lentil (Lens culinaris L.cv) cultivars, which are indigenous to Turkey. Ten days old seedling lentil plants were subjected to low as 0.5, 1.0 mM and high 2.0 and 5.0 mM boric acid treatments for 7 days. B worked as a growth-promoting nutrient for 0.5, 1.0, and 2.0 mM concentration by enhancing length and weight of both shoot and root tissues, while it started showed its suppression effect on these tissues at 5-mM cocentration, which were obtained more dramatic for green lentil in comparison to red lentil. In contrast to this, oxidative stress markers such as MDA, H2O2, and proline concentrations showed increasing trend for 0.5, 1.0, 2.0, and 5.0 mM B treatment, accompanied with a change in photosynthetic pigment concentrations (p < 0.01). MDA in red lentil shoot control was 30,3871 (μmol/gFW) and it was significantly increased to 36,5806 and 51,7414 by the 2.0 and 5.0 B rates, respectively. However, enzymes in anti-oxidation metabolism include superoxide dismutase (SOD), guaiacol peroxidase (GPX), lipoxygenase (LOX), glutathione peroxidase (GSH-Px) activities were obtained higher in high-B-treated groups, while decreased and stable activities were obtained for catalase (CAT) and ascorbate peroxidase (APX) enzymes. CAT and APX activities were higher than those were obtained for 2.0 and 5.0 mM B treatments in both root and shoot tissues. The lentil species manipulated their metabolism to suppress B-stress, and enhanced growth in shoot and root tissues up to 5-mM B stress even though oxidative stress markers showed increasing trend from low B concentrations, 1.0 mM. Therefore, B stress can be claimed as “doubled edge sword” for these lentil species.

Abbreviations

AOS, active oxygen species; APX, ascorbate peroxidase; CAT, catalase; DAB, diamino-benzidine tetrahydrochloride; DMSO, dimethyl sulfoxide DW, dry weight; EDTA, ethylenediamine-N,N,N0,N0-tetraacetic acid; FW, fresh weight GPX, guaiacol peroxidase; GSH-Px, glutathione peroxidase; LOX, lipoxygenase; MDA, malondialdehyde; NBT, nitroblue tetrazolium; PEG, polyethylene glycol; ROS, reactive oxygen species; SOD, superoxide dismutase; H2O2, Hydrogen peroxide;  相似文献   

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