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21.
《Agricultural and Forest Meteorology》1986,37(4):293-308
Soil moisture was measured below sorghum crops of differing density in rainfed trials in increasingly droughty conditions from 1981/2 to 1983/4. Additional measurements were made in sorghum/cowpea intercrops and cowpea monocrops during the drought seasons of 1982/3 and 1983/4.Increasing crop density, by addition of either sorghum or cowpea, resulted in increased effective root activity, which was accompanied by small increases in actual/potential evapotranspiration (Ea/Ep) early in each season. These small increases were followed by small decreases later in the season, but these effects were rarely statistically significant. Both sorghum density and intercropping had little effect on total seasonal water use.Dry matter production increased linearly with increasing seasonal water use. Water use efficiencies of dry weight production were increased by increasing sorghum density. Intercropping in dry conditions did not have significant effects on water use efficiencies. Estimates of soil evaporation suggested that the effects of density on water use efficiency could be attributed to reductions in soil evaporation.The effects of density on reproductive yields were governed by two opposing processes: increasing crop density increased water use efficiencies of dry weight production, but decreased the proportions of dry weight allocated to grain. 相似文献
22.
Chi-Heung Cho Chang-Jun Lee Min-Gyeong Kim Bomi Ryu Jun-Geon Je Yoonsook Kim Sang-Hoon Lee 《Marine drugs》2022,20(6)
Advanced glycation end-products (AGEs) play a vital role in the pathogenesis of diabetic complications. Methylglyoxal (MGO), one of the major precursors of AGEs, is a highly reactive dicarbonyl compound that plays an important role in the pathogenesis of diabetic nephropathy. This study was designed to evaluate the therapeutic potential of phlorotannin-rich Ecklonia cava extract (ECE) on MGO-induced diabetic nephropathy in in vitro models using mouse glomerular mesangial cells. ECE showed anti-glycation activity via breaking of AGEs-collagen cross-links and inhibition of AGEs formation and AGE-collagen cross-linking formation. The renoprotective effects were determined by assessing intracellular reactive oxygen species (ROS) and MGO accumulation, cell apoptosis, and the Nrf-2/ARE signaling pathway. MGO-induced renal damage, intracellular ROS production level, and MGO-protein adduct accumulation were significantly decreased by pretreating ECE. Moreover, ECE pretreatment exhibited preventive properties against MGO-induced dicarbonyl stress via activation of the Nrf2/ARE signaling pathway and reduction of RAGE protein expression in mouse glomerular mesangial cells. Collectively, these results indicated potential anti-glycation properties and prominent preventive effects of ECE against MGO-induced renal damage. Additionally, ECE may be utilized for the management of AGE-related diabetic nephropathy. 相似文献
23.
《Crop Protection》1986,5(4):277-282
Transit times for kiwifruit shipped from California to European markets varied from 16 to 29 days, depending upon the route and transport mode. Temperatures in transit averaged 1·5°C, but ranged from −2° to 13°C. Occasional malfunctions of refrigeration equipment account for the wide range. When the equipment was operating properly, temperatures generally ranged from 0·5° to 3°C. Loss of firmness was the most serious defect in kiwifruit on the European market. Most softening occurred in pre-shipment storage, except in the earliest shipments (October) that had not been stored long; fruit averaged 8·5 kilogram-force (kgf) when harvested, 2·5 kgf when shipped, 1·3 kgf on arrival, and 0·7 kgf after ripening. Decay and other defects were negligible in most test shipments. Soluble solids content did not change appreciably in transit, except in the earliest shipment in which it increased. Ethylene levels did not exceed 44 ppb when the fruit was shipped, and when it arrived in Europe, except in two shipments in which the averages were 58 and 137 ppb, respectively. 相似文献
24.
《Fitoterapia》2014
Thymol, a naturally occurring monocyclic phenolic compound derived from Thymus vulgaris (Lamiaceae), has been reported to exhibit anti-inflammatory property in vivo and vitro. However, the mechanism of thymol is not clear. The aim of the present study was to investigate the effects of thymol on allergic inflammation in OVA-induced mice asthma and explore its mechanism. The model of mouse asthma was established by the induction of OVA. Thymol was orally administered at a dose of 4, 8, and 16 mg/kg body weight 1 h before OVA challenge. At 24 h after the last challenge, mice were sacrificed, and the data were collected by various experimental methods. The results revealed that pretreatment with thymol reduced the level of OVA-specific IgE, inhibited recruitment of inflammatory cells into airway, and decreased the levels of IL-4, IL-5, and IL-13 in BALF. Moreover, the pathologic changes of lung tissues were obviously ameliorated and goblet cell hyperplasia was effectively inhibited by the pretreatment of thymol. In addition, thymol reduced the development of airway hyperresponsiveness and blocked the activation of NF-κB pathway. All data suggested that thymol ameliorated airway inflammation in OVA-induced mouse asthma, possibly through inhibiting NF-κB activation. These findings indicated that thymol may be used as an alternative agent for treating allergic asthma. 相似文献
25.
《Fitoterapia》2014
A new ent-abietane-type diterpene lactone (1) and a new jatrophane-type diterpenoid (2), together with twelve known compounds including three diterpenes (3–5), five triterpenes (6–10) and four sterides (11–14) were isolated from the ethanol extract of the whole plant of Euphorbia lunulata Bge. The structure of compounds 1 and 2 was elucidated on the basis of 1D and 2D NMR spectra and the HR-ESI-MS data. The structure of compound 2 was further analyzed by an X-ray crystallographic study. The in vitro anti-proliferative activities against MCF-7 and NCI-H460 cell lines for compounds 1–5 (diterpene) were evaluated. The results showed marked activity for compound 1 against the two cell lines with the IC50 values 19.5 (NCI-H460) and 18.6 (MCF-7) μM, while for cis-platinum (a positive cytotoxic control agent) 29.7 (NCI-H460) and 27.7 (MCF-7) μM. Compounds 2–5 exhibited moderate cytotoxic activities for the two cell lines with the IC50 values ranging from 32.1 to 58.2 μM. 相似文献
26.
27.
《Veterinary microbiology》2015,175(2-4):185-194
Cyprinid herpesvirus 3 (CyHV3), also known as koi herpesvirus (KHV), can be subdivided primarily into European and Asian genotypes, which are represented by CyHV3-U or CyHV3-I and CyHV3-J, respectively. In this study, the whole genome sequence of a novel Chinese CyHV3 isolate (GZ11) was determined and annotated. CyHV3-GZ11 genome was found to contain 295,119 nucleotides with 52.9% G/C content, which is highly similar to those of published CyHV3-U, CyHV3-I, and CyHV3-J strains. With reference to CyHV3-U, CyHV3-I, and CyHV3-J, CyHV3-GZ11 was also classified into 164 open reading frames (ORF), which include eight repeated ORFs. On the basis of the 12 alloherpeviruses core genes, results from phylogenetic analysis showed that CyHV3-GZ11 had closer evolutionary relationships with CyHV3-U and CyHV3-I than with CyHV3/KHV-J, which were also supported by genome wide-based single nucleotide substitution analysis and the use of a series of developed molecular markers. This study was the first to reveal the presence of a distinct European CyHV3 genotype in East and Southeast Asia at a whole genome level, which will evoke new insights on exploring the origin, evolution, and epidemiology of the virus. 相似文献
28.
29.
Plant NADPH oxidases are key regulators of plant–microbe interactions and reactive oxygen species (ROS) are essential to plant defences against pathogens. A significant part in the role played by ROS has been ascribed to plant respiratory burst oxidase homologs (RBOHs). In potato (Solanum tuberosum), where RBOHs were previously shown to be involved in wound-induced oxidative burst, we assessed their expression after inoculation with Verticillium dahliae Kleb. and showed that StRbohA was the only homolog to be differentially induced in potato in response to inoculation. In order to investigate the potential role of this gene in plant protection against wilt diseases, we used Agrobacterium-mediated transformation of Arabidopsis to assess the effects of its overexpression on plant responses to V. dahliae. After inoculation with this pathogen, the transformed Arabidopsis line overexpressing StRbohA showed lower disease severity (percent damaged leaf area and vascular discoloration) as compared to the wild type. It also had higher ROS production and more cell death caused by hydrogen peroxide (H2O2), compared to the wild type. Suberization of root cells was also more pronounced in the line overexpressing StRbohA, and supports a possible role for StRBOHA in plant resistance to V. dahliae. Together, these findings indicate that overexpressed StRbohA in Arabidopsis enhances the ROS-mediated defence mechanisms against V. dahliae and can be a potential tool to improve plant resistance to this and other soilborne pathogens that cause wilts in economically important crops. 相似文献
30.
The nontarget effects of fresh and used motor oil were studied in a soil test system involving such criteria as earthworm survival, response of soil dehydrogenase and urease, and nitrification. When earthworms were exposed to motor oil-contaminated soil for 4 weeks, the observed median lethal concentrations (LC50) were 40.33 and 3.88 g kg−1 soil for fresh and used oil, respectively. Only fresh motor oil application increased earthworms' body weight even at the higher dose of 19 g kg−1 soil. Gas chromatography/mass spectrometry revealed that used motor oil contained more of aromatic hydrocarbons and heavy metals than fresh oil. This disparity in the chemical composition might be the factor responsible for the significant toxicity of used motor oil towards earthworms. Activities of soil dehydrogenase and urease were significantly enhanced in presence of both the motor oils, while there was a significant inhibition in nitrification by the used motor oil even at a low concentration of 0.2 g kg−1 soil. This study clearly demonstrated that earthworm survival and nitrification could serve as suitable indices to assess motor oil pollution in soil. 相似文献