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191.
Two experiments on land preparation practices, consisting of zero, minimum and conventional tillage treatments, revealed that conventional tillage was the best practice in terms of grain yield, tiller number and weed yield. It was followed by minimum and zero tillage, respectively. A third experiment where zero tillage was associated with dry-seeding with a rolling-injection planter produced yields which were similar to minimum and conventional tillage. Compared to paraquat and SC-0224, glyphosate performed better both in zero and in minimum tillage when followed by harrowing. Application time of paraquat or glyphosate did not affect the grain yield. Butachlor (0.8) application 6 days after seeding significantly increased the grain yield and tiller number. Of the crop establishment methods tested, dry-seeding with a rolling-injection planter in zero tillage, broadcast wet-seeding by hand in minimum tillage and wet-seeding with a low land-seeder in conventional tillage proved to be most suitable. Dry-seeding with a rolling-injection planter proved better in the dry-season, than in the wet-season experiment. 相似文献
192.
Rashid MS 《Science (New York, N.Y.)》1980,208(4446):862-869
High-strength, low-alloy (HSLA) steels have nearly the same composition as plain carbon steels. However, they are up to twice as strong and their greater load-bearing capacity allows engineering use in lighter sections. Their high strength is derived from a combination of grain refinement; precipitation strengthening due to minor additions of vanadium, niobium, or titanium; and modifications of manufacturing processes, such as controlled rolling and controlled cooling of otherwise essentially plain carbon steel. HSLA steels are less formable than lower strength steels, but dualphase steels, which evolved from HSLA steels, have ferrite-martensite microstructures and better formability than HSLA steels of similar strength. This improved formability has substantially increased the utilization potential of high-strength steels in the manufacture of complex components. This article reviews the development of HSLA and dual-phase steels and discusses the effects of variations in microstructure and chemistry on their mechanical properties. 相似文献
193.
Understanding the effect of boron (B) on plant physiology will help to refine the diagnosis of B deficiency and improvement in B fertilizer recommendations for cotton (Gossypium hirsutum L.) growing areas. This study shows the testing of hypotheses “that application of B-fertilizer improves net photosynthetic rate (PN) and water use efficiency (WUE) for cotton plant on a B-deficient soil [< 0.50 mg B kg?1 hydrochloric acid (HCl)-extractable] in an arid environment”. Thus, a permanent layout [two-year field experiment (2004 and 2005)] was conducted to study the impact of B fertilizer at 0, 1.0, 1.5, 2.0, 2.5, and 3.0 kg ha?1 on gas exchange and electrolyte leakage (EL) characteristics of cotton crop (cv. ‘CIM-473’). The soil at experimental site was alkaline (pH 8.1), calcareous [calcium carbonate (CaCO3 5.6%)], and silt loam (Typic Haplocambid). Boron use decreased EL of plant membrane (P ≤ 0.05), and increased PN, transpiration rate (E) and stomatal conductance (gs), while intercellular concentration of carbon dioxide (CO2; Ci) significantly decreased (P ≤ 0.05) during both experimental years. There was a positive, but non-significant effect of B concentration on chlorophyll content in plant leaves. Application of 3.0 kg B ha?1 improved WUE up to 9.7% [4.62 μmol (CO2) mmol?1 water (H2O)] compared to control plants (4.21 [μmol (CO2) mmol?1 (H2O)]. Principal component analysis (PCA) of data indicates positive correlations between leaf B concentration and PN, E, gs, and WUE, while a negative relationship existed between leaf B concentration and intercellular CO2 (Ci). This study showed that addition of B fertilizer in the B-deficient calcareous soil proved beneficial for growth and development for cotton crop by enhancing its WUE and gas exchange characteristics. 相似文献
194.
Evaluating and implementing social–ecological systems: A comprehensive approach to sustainable fisheries
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Robert L. Stephenson Stacey Paul Melanie Wiber Eric Angel Ashleen J. Benson Anthony Charles Omer Chouinard Marc Clemens Dan Edwards Paul Foley Lindsay Jennings Owen Jones Dan Lane Jim McIsaac Claire Mussells Barbara Neis Bethany Nordstrom Courtenay Parlee Evelyn Pinkerton Mark Saunders Kevin Squires U. Rashid Sumaila 《Fish and Fisheries》2018,19(5):853-873
Fisheries sustainability is recognized to have four pillars: ecological, economic, social (including cultural) and institutional (or governance). Although international agreements, and legislation in many jurisdictions, call for implementation of all four pillars of sustainability, the social, economic and institutional aspects (i.e., the “human dimensions”) have not been comprehensively and collectively addressed to date. This study describes a framework for comprehensive fisheries evaluation developed by the Canadian Fisheries Research Network (CFRN) that articulates the full spectrum of ecological, economic, social and institutional objectives required under international agreements, together with candidate performance indicators for sustainable fisheries. The CFRN framework is aimed at practical fisheries evaluation and management and has a relatively balanced distribution of elements across the four pillars of sustainability relative to 10 alternative management decision support tools and indicator scorecards, which are heavily focused on ecological and economic aspects. The CFRN framework has five immediate uses: (a) It can serve as a logic frame for defining management objectives; (b) it can be used to define alternate management options to achieve given objectives; (c) it can serve as a tool for comparing management scenarios/options in decision support frameworks; (d) it can be employed to create a report card for comprehensive fisheries management evaluation; and (e) it is a tool for practical implementation of an integrated social–ecological system approach. 相似文献
195.
Oral administration of Saccharomyces boulardii alters duodenal morphology,enzymatic activity and cytokine production response in broiler chickens
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Yajing Sun Imran Rashid Rajput Muhammad Asif Arain Yanfei Li Dost Muhammad Baloch 《Animal Science Journal》2017,88(8):1204-1211
The present study evaluated the effects of Saccharomyces boulardii on duodenal digestive enzymes, morphology and cytokine induction response in broiler chicken. A total of 200 birds were allotted into two groups (n = 100) and each group divided into five replications (n = 20). The control group was fed basal diet in addition to antibiotic (virginiamycin 20 mg/kg), and treatment group received (1 × 108 colony‐forming units/kg feed) S. boulardii in addition to basal diet lasting for 72 days. The results compared to control group revealed that adenosine triphosphatase, gamma glutamyl transpeptidase, lipase and trypsin activities were higher, while, no significant improvement was observed in amylase activities in the duodenum of the treatment group. Moreover, morphological findings showed that villus height, width and number of goblet cells markedly increased. Additionally, transmission electron microscopy visualized that villus height, width and structural condensation significantly increased in the treatment group. The immunohistological observations showed increased numbers of immunoglobulin A (IgA)‐positive cells in the duodenum of the treatment group. Meanwhile, cytokine production levels of tumor necrosis factor‐α, interleukin (IL)‐10, transforming growth factor‐β and secretory IgA markedly increased, and IL‐6 statistically remained unchanged as compared to the control group. These findings illustrated that initial contact of S. boulardii to the duodenum has significant impact in improving enzymatic activity, intestinal morphology and cytokine response in broiler chicken. 相似文献
196.
Saeed El-Ashram Fathi Abouhajer Maged El-Kemary Guangping Huang Güngör Dinçel Rashid Mehmood Min Hu Xun Suo 《Veterinary research communications》2017,41(4):263-277
The interactions between gastric microbiota, ovine host, and Haemonchus contortus portray the ovine gastric environment as a complex ecosystem, where all factors play a pertinent role in fine-tuning each other and in haemeostasis. We delineated the impact of early and late Haemonchus infection on abomasal and ruminal microbial community, as well as the ovine host. Twelve, parasite-naive lambs were divided into four groups, 7 days post-infection (dpi) and time-matched uninfected-control groups; 50 dpi and time-matched uninfected control groups were used for the experiment. Six sheep were inoculated with 5000 H. contortus infective larvae and followed for 7 or 50 days with their corresponding uninfected-control ones. Ovine abomasal tissues were collected for histological analysis and gastric fluids were collected for PH value measurements, microbial community isolation and Illumina MiSeq platform and bioinformatic analysis. Our results showed that Haemonchus infection increased the abomasal gastric pH (P = 0.05) and resulted in necrotizing and inflammatory changes that were more severe during acute infection. Furthermore, infection increased the abomasal bacterial load and decreased the ruminal microbiome. A 7-day infection of sheep with H. contortus significantly altered approximately 98% and 94% of genera in the abomasal and ruminal bacterial profile, respectively (P = 0.04–0.05). However, the approximate altered genera 50 days after infection in the ovine abomasal and ruminal microbiome were about 62% and 69%, correspondingly (P = 0.04–0.05) with increase in some bacteria and decrease in others. Overall, these results indicate that Haemonchus infection plays a crucial role in shaping stomach microbial community composition, and diversity. 相似文献
197.
Ahmad Khakwani Muhammad Imran Iftikhar Ahmad Rashid Waqas Sabir Hussain Sajid Mahmood Nadeem 《Communications in Soil Science and Plant Analysis》2017,48(1):73-82
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
198.
Muhammad Ayaz Urte Stulpinaite Dalia Feiziene Vita Tilvikiene Kashif Akthar Edita Baltrėnaitė-Gedienė Nerijus Striugas Urooj Rehmani Sahib Alam Rashid Iqbal Monika Toleikiene Modupe Doyeni 《Soil Use and Management》2022,38(2):1307-1321
Management of heavy metal-contaminated soil under drought and other harsh hydrological conditions is critical for protecting soil ecosystem services. In this study, we examined the effect of pig manure digestate-derived biochar as a soil amendment (15 t ha−1) with N fertilizer (180 kg ha−1) on soil and plant heavy metal levels and nutrient availability under various moisture regimes (optimal moisture ~15%, drought condition ≤5%, and flooded condition ≥35% wt.). It was observed that biochar applications significantly decreased heavy metals in the spring wheat plants, lowering Cr by 90%, Ni by 50%, Cd by 9% and Pb by 34% compared to non-biochar (control) treatments. However, the pig digestate-derived biochar increased heavy metals in soil under all moisture regimes, increasing soil Cr by 21%, Ni by 43%, Cu by 55%, Zn by 70%, and Pb by 12%. The availability of macroelements also increased with the biochar applications under the optimum moisture regimes in both soil and plants, increasing Mg2+ by 11%, P by 4%, K+ by 50%, and Ca2+ by 56% in the soil, and Mg2+ by 13%, P by 69%, K+ by 29, and Ca2+ by 39% in plants. Biochar addition also improved chlorophyll fluorescence (CF) levels in the crop for the entire season (12th to 62nd day) and the aboveground crop biomass and dry matter contents both increased. Consequently, the use of pig manure digestate-derived biochar with N fertilizer under normal moisture conditions was able to reduce heavy metal availability to plants and thus could be used in contaminated soils to maintain better crop growth and development. 相似文献