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51.
Tropospheric ozone (O3) has long been documented to cause an injury to plants, but a plants’ protectant, widely applicable in agronomical practice, does not exist. We evaluated the potential antiozonate efficacy of the antitranspirant di-1-p-menthene (Vapor Gard) compared with ethylenediurea (EDU) on Bel-W3 tobacco plants. Plants were treated either with water, or by EDU (10, 100, and 500 mg dm?3), or by vapor (1, 5, 10, and 50 ml dm?3) and were exposed either to O3-enriched (90 ppb) or O3-free air, for 12 days and 8 h day?1. EDU when applied at 10 mg dm?3 did not protect the plants against O3, but when applied at 100 and 500 mg dm?3 offered a significant protection to the plants. Vapor, when applied at 1 ml dm?3 did not protect the plants against O3, neither by terms of foliar visible injury nor by terms of aboveground biomass. In addition, when applied at 10 and 50 ml dm?3 caused phytotoxicity to all the plants, which it was expressed as necrotic spots on the leaves’ surface, misshaping of the leaves, or short plants' height. It is obvious that vapor does not protect Bel-W3 tobacco plants against O3. The antiozonate role of di-1-p-menthene is species-specific and probably occurs only under short-term exposures.  相似文献   
52.
The effectiveness of lignite fly ash for stabilization of Pb,Zn and Cd in tailings and contaminated soils was examined. Flyash was mixed with the contaminated soil or oxidic tailingssamples at various doses and pot experiments were performed.The effectiveness of stabilization was mainly evaluated by thestandard US EPA TCLP toxicity test. The 5-stage sequentialextraction procedure was also applied to determine the form ofcontaminants in the fly ash amended soil or tailings samples.Complementary EDTA extraction tests were also carried out. Thefly ash treatment resulted in the reduction of TCLP solubilityof Pb, Zn and Cd to below the respective regulatory limits at5 and 10% w/w fly ash addition rates in tailings and soil,respectively. Speciation of lead, in the treated soil andtailings samples indicated that there was a significanttransition of the heavy metals form from the exchangeable andcarbonate fractions to reducible and residual, suggesting thatthe potential mechanisms of heavy metals retention are, apartfrom increase of pH, sorption on the oxides and hydroxidessurfaces and binding with the hydrated fly ash compounds.  相似文献   
53.
A method is reported for species quantification by exploiting single-nucleotide polymorphisms (SNPs). These single-base changes in DNA are particularly useful because they enable discrimination of closely related species and/or varieties. As a model, quantitative authentication studies were performed on coffee. These involved the determination of the percentage of Arabica and Robusta species based on a SNP in the chloroplastic trnL(UAA)-trnF(GAA) intraspacer region. Following polymerase chain reaction (PCR), the Robusta-specific and Arabica-specific fragments were subjected to 15 min extension reactions by DNA polymerase using species-specific primers carrying oligo(dA) tags. Biotin was incorporated into the extended strands. The products were captured in streptavidin-coated microtiter wells and quantified by using oligo(dT)-conjugated photoprotein aequorin. Aequorin was measured within 3 s via its characteristic flash-type bioluminescent reaction that was triggered by the addition of Ca(2+). Because of the close resemblance between the two DNA fragments, during PCR one species serves as an internal standard for the other. The percentage of the total luminescence signal obtained from a certain species was linearly related to the percent content of the sample with respect to this species. The method is accurate and reproducible. The microtiter well-based assay configuration allows high sample throughput and facilitates greatly the automation.  相似文献   
54.
Sewage sludge treated with 15% bentonite, vermiculite or biochar was evaluated as a soil amendment in comparison to limed and untreated sludge. Seven treatments were established to two soils, an acid and an alkaline, in three replications, i.e. 2% addition of sludge treated with bentonite, vermiculite, biochar and lime and application of 2% untreated sludge, inorganic fertilization and no sludge or inorganic fertilizers (control). Then, the soil treatments were used in a pot experiment with perennial ryegrass (Lolium perenne L.) as a test plant. Sludge treated with the clay minerals or biochar improved pH of the acid soil and significantly increased organic matter and available nutrients of both soils compared to control. Although no salinity or sodicity hazard was evidenced, the initial salinity of acid and alkaline soil increased by four-eight and two-three times, respectively, upon addition of all sludge treatments, especially that of untreated sludge. Moreover, soil available zinc (Zn) increased by four-eight times. Soil application of sludge treated with the clay minerals or biochar increased the total aboveground biomass yield of ryegrass in the acid and alkaline soil by 133%–171% and 72%–88%, respectively, compared to control and enhanced nutrient uptake by plants. Furthermore the microbial metabolic quotient indicated lack of low pH and heavy metal stress with addition of sludge to the acid soil. After three harvests of ryegrass, the residual effect of sludge on pH of acid soil and salinity, available phosphorus (P), Zn and boron (B) of both soils still persisted. Thus sewage sludge treated with 15% bentonite, vermiculite or biochar could be applied to soils at a rate of 2% (≈80 Mg ha−1) to serve as soil amendment and fertilizer for grasses and pasture species; however, caution is needed regarding possible P build-up, Zn phytotoxicity and salinization risks.  相似文献   
55.
The in vitro response of the apple rootstock MM 111 to increasing concentrations of boron (B) (0.1, 0.5, 1, 3, and 6 mM) in MS medium is reported. The in vitro cultures of MM 111 shoots produced the highest fresh mass when 0.1 mM B was included in the medium. By increasing B concentration of the culture medium from 0.1 to 6 mM, B, phosphorus (P), calcium (Ca), and magnesium (Mg) concentrations of explants increased, whereas potassium (K), iron (Fe), manganese (Mn), and zinc (Zn) concentrations decreased. Chlorophyll content (SPAD units) of leaves declined as B concentration of the culture medium increased from 0.1 to 6 mM. The highest peroxidase (POD) activity in leaves was recorded in the presence of 6 mM B in the medium. By increasing B concentration of the medium from 0.1 to 3 mM, catalase (CAT) activity increased in leaves. Superoxide dismutase (SOD) activity in leaves and stems increased as B concentration of the medium increased. The non-enzymatic antioxidant power activity of leaves (FRAP values) increased gradually as B concentration of the medium increased.  相似文献   
56.
A 2-year study was conducted in northern Greece to assess the ability of 29 six-row and 21 two-row barley (Hordeum vulgare L.) cultivars to compete with winter wild oat [Avena sterilis spp. ludoviciana (Durieu) Gill & Magne] and German-madwort (Asperugo procumbens L.). The fresh weight of both weeds grown in competition with six of the most competitive six-row barley cultivars (Bulk Resist. Desc-Sutter, Lignee 640, Paico's, Mantnan's-EH 165, Pistacho and Malebo) was reduced by 61–75% compared with one of the least competitive six-row cultivars [Gloria's-Copal's (30B-4Y-20M)]. The corresponding fresh weight reduction of both weeds grown in competition with three of the most competitive two-row barley cultivars (Goldmarker, Shanon and Helena) ranged from 59 to 76% compared with one of the least competitive two-row cultivars (Guanajuato). The ability to withstand competition (AWC) from winter wild oat and German-madwort of the six-row and two-row cultivars ranged from 33.7 to 78.3% and 26.7 to 69.2%, respectively. Representative yield losses ranged from 24 to 68% and 30 to 75%, respectively. The corresponding ability to compete (AC) indices ranged from 22.5 to 64.8% and 21.1 to 59.1%. The results of this study indicated that the barley cultivars Ligne 640 and Pistacho (2B-1Y-1B) had high AWC from winter wild oat and German-madwort and provided high grain yield in both weedy and weed-free conditions. Consequently, they could successfully be used in Mediterranean organic (no herbicide use) and conventional agricultural systems with reduced herbicide use. Barley cultivars with high AC and ability to produce high grain yield under weedy conditions [with Bulk Resist. Desc-Sutter, Arupo's and Gloria's-Copal's (30B-4Y-23M) among the most efficient] could also successfully be used in organic fields infected by the two weeds.  相似文献   
57.
An increasing demand for cherry production (Prunus avium L.) in Greece led to the development of new high quality sweet cherry cultivars. Self-incompatibility in cherry is one of the most challenging issues for the species’ cultivation and top breeding priority. Τhe present study focuses on the development of new hybrids with improved traits such as productivity, fruit size, organoleptic characteristics and self-compatibility. For this purpose, thirty different cultivars were crossed and produced hybrids that were evaluated according to 34 morpho-physiological characteristics. The results were analyzed using the XLSTAT (version 2014.1) software and a dendrogram was constructed using the agglomerative hierarchical clustering method. Optimal hybrid clustering was achieved when characteristics of great economic importance such as fruit shape and size, growth habit and days to blooming were included in the analysis. Based on the results, new sweet cherry hybrids with the special character of self-compatibility were developed. Our findings provide crucial new information for sweet cherry future breeding programs and cultivation.  相似文献   
58.
The high polyphenol content of the wastewater is the major environmental problem caused by the olive mills. A pilot scale system for the treatment of the olive oil mills wastewater was developed aiming at the recovery of high added value-contained polyphenols and the reduction of the environmental problems. The treatment system consists of three main successive sections: The first one includes successive filtration stages aiming at the gradual reduction of the wastewater suspended solids up to a limit of 25 microm. The second section includes passing of the filtered wastewater through a series of adsorbent resins (XAD16 and XAD7HP) in order to achieve the de-odoring and decolorization of the wastewater and the removal/ recovery of the polyphenol and lactone content. The third section of the procedure includes the thermal evaporation and recovery of the organic solvents mixture, which has been used in the resin regeneration process, and finally the separation of the polyphenols and other organic substance contents using fast centrifuge partition chromatography. The final outcome of the whole procedure is (i) an odorless yellowish wastewater with a 99.99% reduced content in polyphenols and 98% reduced COD, (ii) an extract rich in polyphenols and lactones with high antioxidant activity and high added value, (iii) an extract containing the coloring substances of the olive fruit, and (iv) pure hydroxytyrosol.  相似文献   
59.
The biological screening of 44 marine sponge extracts for the research of bioactive molecules, with potential application in the treatment of age-related diseases (cancer and Alzheimer’s disease) and skin aging, resulted in the selection of Scopalina hapalia extract for chemical study. As no reports of secondary metabolites of S. hapalia were found in the literature, we undertook this research to further extend current knowledge of Scopalina chemistry. The investigation of this species led to the discovery of four new compounds: two butenolides sinularone J (1) and sinularone K (2), one phospholipid 1-O-octadecyl-2-pentanoyl-sn-glycero-3-phosphocholine (3) and one lysophospholipid 1-O-(3-methoxy-tetradecanoyl)-sn-glycero-3-phosphocholine (4) alongside with known lysophospholipids (5 and 6), alkylglycerols (7–10), epidioxysterols (11 and 12) and diketopiperazines (13 and 14). The structure elucidation of the new metabolites (1–4) was determined by detailed spectroscopic analysis, including 1D and 2D NMR as well as mass spectrometry. Molecular networking was also explored to complement classical investigation and unravel the chemical classes within this species. GNPS analysis provided further information on potential metabolites with additional bioactive natural compounds predicted.  相似文献   
60.
The objective of the study was to determine the immunohistochemical expression of canine TERT in canine testicular tumours comparing two different antibodies for TERT, and to correlate them with well established markers specific to dividing cells such as PCNA and ki67, and with expression of the p53 tumour suppressor gene. The study included 36 cases of canine testicular tumours, which were categorized as 12 Sertoli Cell Tumours (SCT), 20 seminomas, 3 interstitial cell tumours and 1 mixed germ cell-sex cord stromal tumour (MT). Two antibodies for hTERT were examined; a highly specific TERT antibody, RCK-hTERT, was evaluated for the first time. Immunodetection of RCK-hTERT was observed in 31% of tumours examined (6/20 Seminomas, 4/12 SCT, 1/3 interstitial cell tumour and 0/1 mixed germ cell-sex cord stromal tumour), while the NCL-hTERT in 67% of them (15/20 Seminomas, 6/12 SCT, 3/3 interstitial cell tumour and 0/1 ΜΤ). PCNA immunoreactivity was detected in all cases. Regarding ki67, 3 SCT, 12 seminomas and all interstitial cell tumours showed clear immunoreaction. p53 immunoreactivity was detected in 6 SCT, 15 seminomas and all interstitial cell tumours. The immunohistochemical expression of both TERT antibodies are discussed and compared in order to clarify their potential usefulness in canine testicular malignancies in relation to the expression of well known cell cycle markers. Our results indicate that TERT and PCNA are useful proliferation markers but not helpful to evaluate prognosis. Instead of that ki67 and p53 could be used for predicting aggressiveness in this group of tumours  相似文献   
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