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891.
This study provided an insight on improving soil-plant micronutrients availability in response to poultry manure (PM), wheat milling residues (WMR) and urea N (UN) and their integration in wheat–soybean cropping system. The treatments were: control; poultry manure full, PM100; wheat milling residues full, WMR100; urea N full, UN100; PM half and WMR half, PM50+WMR50; UN50+PM50; UN50+WMR50; UN50+PM25+WMR25. All amendments were added at the rate or equivalent to 100 kg total N ha–1. Results indicated that the integrated treatments increased Cu, Fe, Mn and Zn uptake of wheat by 35.7–103%, 48.4–111.1%, 85.2–267.0% and 33.8–128.2%, respectively over control. In soybean the corresponding increase in micronutrient uptake (Cu, Fe, Mn and Zn) was 18.3–60.3%, 27.5–87.4%, 14.1–54.6% and 13.2–58.0% in integrated treatments. The post-harvest soil analysis indicated 2 to 3-fold increase in micronutrient content with highest values in PM100 i.e., 2.66 mg kg?1 for Cu, 14.41 mg kg?1 for Fe, 18.58 mg kg?1 for Mn and 2.44 mg kg?1 for Zn, respectively. The results showed that the PM either alone or in integrated with WMR and UN can be an effective management strategy for improving micronutrient content of soil–plant.  相似文献   
892.
This study was conducted to assess the efficacy of bio-organic phosphate (BOP) and diammonium phosphate (DAP) fertilizers for improving the growth, yield, plant phosphorus (P) content and profitability of wheat cultivation under systems of wheat intensification (direct seeding and nursery transplantation) and conventional sowing (broadcasting). BOP was formulated by enriching the compost with rock phosphate and inoculated with plant growth-promoting rhizobacterial (PGPR) strain, Bacillus thuringiensis strain K5. Results revealed the supremacy of BOP over DAP, and the direct seeding method over the other sowing methods in almost all parameters studied. The application of BOP significantly (p ≤ 0.05) increased the plant height, root length, number of tillers per plant, wheat biomass, number of grains per spike, 1000-grain weight, grain yield, straw and grain P contents in direct seeded wheat in comparison to DAP fertilization. Furthermore, application of BOP and direct seeding of wheat generated more profit per hectare compared with the other treatments.  相似文献   
893.
Nitrogen has a role in plant mineral nutrition, and so a better way of supplying nitrogenous fertilizers is demanded to promote plant nutrition and clean environment. The present study was, therefore, designed to maintain plant mineral requirements and control environmental pollution. Tomato cultivars, that is, Falcon and Rio Grande, were supplied with a mixture of poultry manure (PM) and urea in various proportions in 2009 and 2010. All tested factors (N source, cultivar, and year) alone and in combination significantly (P ≤ 0.05) affected the mineral profile of tomato fruit. Treatment 75:25 resulted in highest uptake of calcium (Ca), iron (Fe), zinc (Zn), and copper (Cu) in cultivar Rio Grande during 2010. Similarly, highest concentration of boron (B) was recorded in Rio Grande fed with 50:50 of PM and urea, respectively. It was concluded that a combination of PM and urea in ratios of 75:25 and 50:50 performed well in achieving the optimal mineral contents in the tomato fruits.  相似文献   
894.
Field experiment was conducted to investigate the impact of phosphorus (P) and beneficial microorganism (BM) on the yield and yield components wheat (Triticum aestivum L., cv. Siren-2010). The experiment was conducted under full (five irrigations) and limited (two) irrigation conditions at the Research Farm of The University of Agriculture Peshawar during winter 2012–13. The experiment under both full and limited irrigated conditions was laid out in randomized complete block design using three replications. The results showed that irrigated plots produced more spikes m?2 (254), grains spike?1 (55.5), heavier thousand grains weight (39.4 g), and higher grain yield (3612 kg ha?1 than limited irrigated condition. Application of P at the highest rate (90 kg P ha?1) produced more spikes m?2 (260) and grains spike?1 (52.4), and increased maximum thousand grain weight (39.1 g) and grain yield (3617 kg ha?1). Application of BM at the highest rate (30 L ha?1) resulted in maximum number of spikes m?2 (257) and grains spike?1(51.7), highest thousand grains weight (39.1 g) and grain yield (3765 kg ha?1). The results confirmed that under full irrigated condition the increase in both P and BM levels (90 kg P ha?1 and 30 L ha?1, respectively) and under limited irrigated condition the intermediate levels of both P and BM (60 kg P ha?1 and 20 L ha?1, respectively) could increase wheat productivity under semi-arid conditions.  相似文献   
895.
Development of crop cultivars with high yield under low nitrogen (N) supply is a basic approach for the enhancement of agricultural sustainability. The previous studies showed that Tibetan wild barley shows wider genetic diversity in abiotic stress and poor fertility tolerance. In this study, four barley genotypes (two Tibetan wild and two cultivated), differing in N use efficiency (NUE), were characterized for their growth and physiological responses to low N stress. The genotypes ZD9 (cultivated) and XZ149 (wild) with high NUE performed better in terms of shoot dry weight (DW) and photosynthetic parameters under both low and normal N levels and had higher antioxidative enzyme activities, N concentration, and accumulation in both shoots and roots under low N stress. The current results showed the substantial difference among barley genotypes in low N tolerance and verified the significance of Tibetan wild barley in the genetic improvement of cultivated barley in NUE.  相似文献   
896.
Ten mungbean (Vigna radiata R. Wilczek) genotypes were evaluated for grain yield and phosphorus (P) efficiency at adequate and deficient P in soil. Genotypes differed significantly in plant height, grain yield, P accumulation (PA), and other P-efficiency parameters at both P levels. The genotype “AEM-40/30” had maximum plant height, grain yield, and phosphorus physiological efficiency index (PPEI) under P deficiency. The genotypes were distributed into nine groups based on their relationship between total PA and grain yield at deficient P level. Moreover, genotypes were categorized into low, medium, or high efficient for each parameter by allotting index score (1, 2, or 3). Maximum cumulative index score (25) was attained by the genotypes “AEM-40/30 and AEM-20/3/87”, and genotype “AEM-30/5/8/90” scored least total index (14). The significant differences among mungbean genotypes for PA, phosphorus harvest index (PHI), PPEI, and grain yield can be exploited to select or identify P-efficient mungbean genotypes.  相似文献   
897.
Acute (24 hours) and chronic (90 days) oral toxicity studies on the ethanolic extracts of common spices Cinnamomum zeylanicum Nees bark and Piper longum L. fruits were carried out in mice. Acute dosages were 0.5, 1.0 and 3 g/kg while the chronic dosage was 100 mg/kg/day. All external morphological, hematological and spermatogenic changes, in addition to body weight and vital organ weights, were recorded. The extracts of both the plants caused no significant acute or chronic mortality compared to the control during this study. During chronic treatment there was no significant change in the pre- and post treatment body weight of the test animals while the weight gain in the control group was significant. C. zeylanicum treatment caused reduction in liver weight while P. longum caused a significant increase in the weight of the lungs and spleen of the treated animals compared to the control. Hematological studies revealed a significant fall in hemoglobin level of C. zeylanicum treated animals. Both of the extracts induced a significant increase in reproductive organ weights, sperm motility, sperm count and failed to illicit any spermatotoxic effect.  相似文献   
898.
Measurements and theoretical calculations are reported for an interatomic multi-atom resonant photoemission (MARPE) effect that permits direct determination of near-neighbor atomic identities (atomic numbers). MARPE occurs when the photon energy is tuned to a core-level absorption edge of an atom neighboring the emitting atom, with the emitting level having a lower binding energy than the resonant level. Large peak-intensity enhancements of 33 to 105 percent and energy-integrated effects of 11 to 29 percent were seen in three metal oxides. MARPE should also be sensitive to bond distance, bonding type, and magnetic order, and be observable via the secondary processes of x-ray fluorescence and Auger decay.  相似文献   
899.
Various physiological functions of dietary glucosylceramides (GlcCer) have been reported, such as preventing colon cancer and improving skin barrier function. One potential GlcCer source used as a foodstuff is sea cucumber. In this study, our objective was to determine the effect of dietary GlcCer prepared from sea cucumber on plasma and liver lipids in cholesterol-fed mice. ICR mice were fed four different diets (control diet, sea cucumber GlcCer supplemented diet, high cholesterol supplemented diet, and high cholesterol + sea cucumber GlcCer supplemented diet). Dietary GlcCer decreased total cholesterol significantly in ICR mice. The mRNA expression of LDL receptor was increased significantly, while the expression of the gene CYP7A1, which is involved in bile acid formation, was decreased significantly compared with the control (diet without cholesterol). These results suggest that the expression of the cholesterol homeostasis gene in liver is modulated due to the cholesterol lowering effect of dietary GlcCer.  相似文献   
900.
As guppies are one of the commercially important fish in freshwater ornamental aquaculture industry, it is important to gain an understanding of guppy immune response for infectious disease control. Till now, the number of study that examined the immune response of guppies is limited and effective tools for monitoring guppy antibody have not been reported. In this study, we successfully isolated guppy IgM using mannan-binding protein (MBP) affinity chromatography and produced specific polyclonal antibodies against guppy IgM heavy and light chains, that showed a molecular weight of approximately 74 and 23 kDa respectively. The produced polyclonal antibodies were used to develop an enzyme-linked immunosorbent assay (ELISA) and have demonstrated to be an effective tool for the detection and quantification of antigen-specific antibody of guppies immunized with Pseudomonas fluorescens. In conclusion, the produced anti-guppy IgM polyclonal antibodies should prove its future implications for immunology and epidemiology studies in guppies.  相似文献   
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