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1.
The apparent digestibility coefficients (ADCs) of amino acids (AA), protein, and energy in six feed ingredients (Brazilian fish meal, soybean meal, corn gluten meal, alcoholic yeast, corn, and wheat bran) we evaluated for pacu juveniles. In general, all ingredients showed high digestibility values for all AA, and differences among ADCs of individual amino acid were detected ( P < 0.01). Corn gluten, soybean, and fish meals had the highest ADCs of AA. The ADCs of protein in fish meal, yeast, and corn gluten meal should not be used as AA digestibility indicators, because those showed differences up to 6.7% between the ADCs of protein and AA. All ingredients had lower ADCs of energy than corn gluten meal ( P < 0.01). Lysine was the first limiting amino acid in fish meal, corn gluten meal, wheat bran, and corn, and the second limiting amino acid in soybean meal, as methionine was the first limiting amino acid in soybean meal and yeast. However, the soybean meal was the best quality protein source, as it had the highest digestible essential amino acid index. This demonstrated that digestible amino acid values can be used to formulate practical diets for pacu, preventing potential deficiencies or excess that might cause environmental and economic losses. 相似文献
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S. Gupta R. Kaushal R. S. Spehia S. S. Pathania V. Sharma 《Journal of plant nutrition》2017,40(7):921-927
Inorganic fertilizers alone cannot sustain high levels of productivity. This study was conducted to determine whether higher productivity of capsicum could be achieved by conjoint application of chemical fertilizers and plant growth promoting rhizobacteria (PGPR). Four PGPR isolates (RS2, RS3, RS4, and RS7) from capsicum roots and rhizosphere were evaluated at Solan, Himachal Pradesh (India), during 2009–2012. Two best performers: RS2 and RS7 were tried singly or in consortium with different levels of chemical fertilizers under field conditions, Randomized Block Design, replicated thrice. The conjoint use of 100% recommended nitrogen, phosphorus, and potassium (NPK) doses through chemical fertilizers (RDF) plus PGPR significantly increased fruit yield, plant height, and biomass by 37%, 20%, and 30%, respectively, over sole application of 100% RDF (control). Further, response of capsicum to 80% RDF plus PGPR was statistically comparable with control. The results, therefore, indicate the potential of isolated PGPR strains to substitute about 20% NP fertilizers besides enhanced productivity of capsicum. 相似文献
4.
化学灌浆在混凝土细裂缝治理中的应用 总被引:1,自引:0,他引:1
详细介绍了化学灌浆的施工技术、设备及化学灌浆材料,结合工程实例加以论述,并证实与缝表面嵌填封涂的处理方式比较,化学灌浆治理混凝土细裂缝更为行之有效. 相似文献
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S. Spasibionek 《Plant Breeding》2006,125(3):259-267
Seeds of the winter oilseed rape (Brassica napus L.) line PN 3756/93 were treated with ethyl methanesulphonate to induce mutations in the fatty acid biosynthetic pathway. The seed mutagenic treatment was repeated in the M2 generation. After treatments, individual seed and plant selections were made for changes in fatty acid composition during several generations of inbreeding. Self‐pollinated plants with changed fatty acid compositions were inbred to obtain genetically homozygous and stable mutant lines. Two mutants, M‐10453 and M‐10464, with increased levels of oleic acid (approximately 76%) and reduced linoleic and linolenic acid contents (8.5% and 7.5%, respectively) were selected. Gene or genes controlling desaturation of oleic acid were probably mutated in these plants. The third mutant, M‐681 had a very low linolenic acid content (approximately 2.6%) and increased linoleic acid content (approximately 26%). This would suggest the occurrence of mutations in genes controlling linoleic acid desaturation. The results of selection work during several generations showed that the environment had substantial influence on the composition of seed oil. This made the search for mutants with modify fatty acid compositions difficult. The induced mutants are not directly usable as new varieties, but can be used as parents in crosses for the development of high quality rapeseed varieties. 相似文献
6.
Spodoptera litura is one of the most destructive pests in Pakistan and in many other regions of the world. A field collected population of S. litura was selected with spinosad for eleven generations under controlled laboratory conditions to study the cross resistance, mechanism and stability of spinosad resistance in S. litura. The resistance to spinosad in S. litura increased 3921-fold (after eleven generations of selection with spinosad) as compared to a susceptible population of S. litura. No cross resistance between spinosad and emamectin benzoate, methoxyfenozide, fipronil, indoxacarb, profenofos, lufenuron or deltamethrin was found in the spinosad-selected population of S. litura. To find the possible mechanism of spinosad resistance in S. litura two synergists, Piperonyl butoxide (PBO), S, S, S-tributyl phosphorotrithioate (DEF) were tested on the susceptible and resistant strains and on the un-selected field population. The values of the synergism ratios of PBO and DEF were 2.33 and 1.06 for the spinosad-selected strain, 1.36 and 1.06 for the un-selected field population and 1.14 and 1.00 for the susceptible strain, respectively. As high PBO ratio indicates the role of microsomal O-demethylase in causing spinosad resistance in S. litura. The spinosad-resistant and field populations of S. litura were reared without any selection pressure from the 12th to the 16th generation (G12–G16). The spinosad resistance decreased from 3921 to 678-fold in the spinosad-resistant population and from 31.1 to 15.1-fold in the un-selected population of S. litura as compared to the susceptible strain. Spinosad resistance in S. litura has a high reversion rate (−0.15) which indicates that spinosad resistance in S. litura is unstable and can be easily managed by switching off the selection pressure for a few generations or alternating with insecticides having different modes of action. 相似文献
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The study of food-grade isolated kafirin proteins has increased recently due to the interest of their potential applications in gluten-free products. However, functionality of extracted proteins and fractions have been poorly characterized. In this investigation, kafirins were extracted from whole or decorticated sorghum genotypes (white-regular, white-waxy, red-regular and high-tannin) with 70% aqueous ethanol with metabisulfite. Chemical composition, color parameters, functionality and molecular characterization of kafirin extracts were determined. When kafirin extracts were obtained from decorticated sorghums, higher protein purities (81.5–93.3%), lower lipid contents (1.9–12.6%), better color parameters, and higher yields were obtained compared to counterparts extracted from whole caryopses. Functional properties of the extracted kafirins showed low water solubility, free amino nitrogen, and emulsifying activity, but adequate water holding and fat absorption capacities and in vitro protein digestibility. Differences in functionality were attributed to sorghum genotype. SDS-PAGE showed extraction of α1-, α2-, β-, and γ-kafirins with no contamination of other protein fractions. FTIR indicated a reduction in α-helix:β-sheet after extraction, especially in proteins obtained from decorticated sorghums. High correlations found from Pearson analysis could be used to optimize protein yield and the functionality (emulsifying activity and solubility) of the extracted proteins to be applied in gluten-free food systems. 相似文献
9.
1989到1991年对10年生国光和金帅苹果品种的果树进行的渗灌试验结果如下:1,能节水并可防涝;2,可增加土壤孔隙度,提高土壤养分含量;3,增加吸收根数量,促进树体的生长发育。座果率和单株(或单位面积)产量均比漫灌(对照)区高;4,到1991年,果品质量有了明显的改善;5,多孔陶土管成本低;6,田间管理方便。 相似文献
10.
《Veterinary anaesthesia and analgesia》2022,49(3):304-307
ObjectiveTo determine the effective dosage of the combination tiletamine–zolazepam–ketamine–xylazine (TKX), with or without methadone, in dogs.Study designProspective, randomized, experimental study.AnimalsA total of 29 dogs.MethodsDogs were randomly administered TKX (group TKX, n = 13) or combined with 0.3 mg kg–1 of methadone (group TKXM, n = 16) intramuscularly. The TKX solution contained tiletamine (50 mg mL–1), zolazepam (50 mg mL–1), ketamine (80 mg mL–1) and xylazine (20 mg mL–1). The effective dosages for immobility in 50% and 95% of the population (ED50 and ED95) were estimated using the up-and-down method. Approximately 20 minutes after drug administration, a skin incision was performed and the response was judged as positive or negative if the dogs moved or did not move, respectively. The TKX volume for the subsequent dog in the same group was increased or decreased by 0.005 mL kg–1 if the response of the previous dog was positive or negative, respectively. Heart and respiratory rates, and sedation/anesthesia scores (range 0–21) were recorded before and 15 minutes after drug administration.ResultsEstimated ED50 and ED95 (95% confidence intervals) were: TKX, 0.025 (0.020–0.029) and 0.026 (0.010–0.042) mL kg–1; TKXM, 0.022 (0.018–0.025) and 0.033 (0.017–0.049) mL kg–1. Median (interquartile range) scores for sedation/anesthesia were 17 (16–18) and 17 (15–20), and times until lateral recumbency were 5 (4–6) and 6 (4–10) minutes in TKX and TKXM, respectively (p > 0.05). In both groups heart and respiratory rates decreased, but values remained acceptable for anesthetized dogs.Conclusions and clinical relevanceThe results provide a guide for volumes of TKX and TKXM in dogs requiring restraint for minimally invasive procedures. Inclusion of methadone in the TKX combination did not influence ED50. 相似文献