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101.
102.
水针疗法(即穴位注射)是在传统针灸技术的基础上发展起来的一种中西结合的疗法,具有针刺和药物的双重作用,在兽医临床上应用广泛。本文概要介绍了近10年来穴位注射治疗家畜外科病及胎产病方面的应用进展。经统计近30篇临床报告表明,穴位注射治疗家畜闪挫伤、风湿症及神经麻痹等868例,治愈747例,治愈率为94.1%;治疗家畜眼病421例,治愈402例,治愈率为95.5%。穴位注射治疗家畜不孕症222例,治愈195例,治愈率为87.8%;治疗乳房炎43例,治愈39例,治愈率90.7%;治疗胎衣不下48例,治愈141例,治愈率为85.4%。  相似文献   
103.
为明确不同寄主植物对桃小食心虫(Carposina sasakii Matsumura)主要代谢物质的影响,选取6种寄主植物(大枣、山楂、梨、桃、苹果、杏)饲喂的桃小食心虫,分别使用过碘酸钠法、硫酸蒽酮比色法和盐酸水解法测定其体内甘油、海藻糖和氨基酸含量;通过定磷法和2,4-二硝基苯肼法测定Na+-K+-ATP酶和LDH酶的活性。结果表明:桃小食心虫体内主要代谢物质含量在不同寄主植物间存在差异,取食山楂的桃小食心虫甘油含量最高(12.48μg/mg),取食大枣次之(12.44μg/mg),取食杏的含量最低(10.43μg/mg);海藻糖含量为取食大枣的最高(27.16μg/mg),取食杏的最低(9.86μg/mg);取食6种寄主的桃小食心虫体内均检测到16种氨基酸,取食山楂的桃小食心虫体内天冬氨酸Asp含量高于取食其他5种寄主植物的;超微量Na+-K+-ATP酶活性测定结果显示取食桃的桃小食心虫活性最高(1.31 U/g pro),LDH酶活性以取食杏的最高(42.73 U/g pro)。  相似文献   
104.
The objective of the present work was to examine the effects of phosphate fertilizers on the microbial activity of pasture soils. Various microbial characteristics were measured using soils from an existing long-term phosphate fertilizer field trial and a short-term incubation experiment. The measurements included basal respiration, substrate induced respiration, inhibition of substrate-induced respiration by streptomycin sulphate (fungal activity) and actidione (bacterial activity) and microbial biomass C. The long-term field trials was initiated during 1985 to examine the effectiveness of different sources of phosphate fertilizers (single superphosphate, North Carolina phosphate rock, partially acidulated North Carolina phosphate rock, and diammonium phosphate) on pasture yield. The incubation experiment was conducted for 8 weeks using the same soil and the sources of phosphate fertilizers used in the field trial. In the incubation experiment the fertilizer addition caused an initial decrease in basal and substrate-induced respiration but had no effect on total microbial biomass. The initial decline in basal and substrate-induced respiration with the fertilizer addition was restored within 8 weeks after incubation. In the field experiment the fertilizer addtion had no significant effect on basal respiration but increased substrate-induced respiration and microbial biomass C. The short-term and the long-term effects of phosphate fertilizer addition on the microbial characteristies of the soils are discussed in relation to its effects on pH, salt concentration, and the nutrient status of the soils.  相似文献   
105.
In this work we studied the influence of Pb, Zn, and Tl on microbial biomass survival and activity during a laboratory incubation of soil. In comparison to uncontaminated soil, the microbial biomass C decreased sharply in soil contaminated with Zn and Tl, whereas the addition of Pb did not have any significant inhibitory effect on the level of microbial biomass C. Zn displayed the greatest biocidal effect, confirmed by the measurement of the death rate quotient (q D). The microbial activity, measured as CO2 evolution, increased significantly in contaminated soils, emphasizing the need of living organisms to expend more energy to survive. The greater demand for energy by microorganisms in order to cope with the toxicity of pollutants was also confirmed by measurement of the metabolic quotient (q CO2). In order to determine whether soil microorganisms affect the bioavailability of these metals through their mobilization and release, we studied the relationships between available Pb, Zn, and Tl, and microbial biomass C. The water-soluble fraction of Tl, available Tl, and Zn, and microbial biomass C were related significantly, but not Pb.  相似文献   
106.
Microbial communities in floodplain soils are exposed to periodical flooding. A long-term submerged Eutric Gleysol (GLe), an intermediate flooded Eutric Fluvisol (FLe), and a short-time flooded Mollic Fluvisol (FLm) at the Elbe River (Germany) with similar organic carbon contents (Corg) between 8.1% and 8.9% were selected to test the quality of phospholipid fatty acids (PLFA), soil microbial carbon (Cmic), basal respiration (BR), metabolic quotient (qCO2), and Cmic/Corg ratio to characterize and discriminate these soils with microbial parameters.The three floodplain soils can be differentiated by Cmic and by total PLFA-biomass. Due to the different flooding durations and the time since the soils were last flooded Cmic and PLFA-biomass increase in the order GLe<FLe<FLm. Both parameters correlate significantly (r=0.999;p<0.05). The Cmic/Corg ratios are low in comparison to terrestrial soils and revealed the same ranking over the three soils like Cmic. Contrary, qCO2 and BR are highest in GLe and lowest in FLm according to inundation regime. The diminished Cmic, high BR, and high qCO2 values in GLe seem to be an unspecific response of aerobic soil microorganisms on the long flooding period and the resulting short time for developing after last flooding as well as the low pH value. Different plant communities and their residues may influence the microbial diversity additionally.The PLFA profiles were dominated by the group of saturated fatty acids that together constituted almost 62-72% of the total fatty acids identified in the soils. In GLe all groups of PLFA, inclusive monounsaturated fatty acids, are lowest and in FLm highest, while in FLe the PLFA fractions show an intermediary amount of the three soils. The FLm had most of the time aerobic conditions and revealed therefore the highest Cmic, PLFA-biomass, especially monounsaturated fatty acids, Cmic/Corg ratio as well as relatively low BR and qCO2 value. These indicate that microorganisms in FLm are more efficiently in using carbon sources than those in GLe and FLe.All 26 identified PLFA were found in FLe and FLm, while the polyunsaturated fungi biomarker 18:2ω6,9c could not be detected in GLe. In this long-time submerged soil the environmental conditions which microorganisms are exposed might be disadvantageous for fungi.  相似文献   
107.
A laboratory experiment was conducted to determine the effect of temperature (2, 12, 22 °C) on the rate of aerobic decomposition of skeletal muscle tissue (Ovis aries) in a sandy loam soil incubated for a period of 42 days. Measurements of decomposition processes included skeletal muscle tissue mass loss, carbon dioxide (CO2) evolution, microbial biomass, soil pH, skeletal muscle tissue carbon (C) and nitrogen (N) content and the calculation of metabolic quotient (qCO2). Incubation temperature and skeletal muscle tissue quality had a significant effect on all of the measured process rates with 2 °C usually much lower than 12 and 22 °C. Cumulative CO2 evolution at 2, 12 and 22 °C equaled 252, 619 and 905 mg CO2, respectively. A significant correlation (P<0.001) was detected between cumulative CO2 evolution and tissue mass loss at all temperatures. Q10s for mass loss and CO2 evolution, which ranged from 1.19 to 3.95, were higher for the lower temperature range (Q10(2-12 °C)>Q10(12-22 °C)) in the Ovis samples and lower for the low temperature range (Q10(2-12 °C)<Q10(12-22 °C)) in the control samples. Metabolic quotient and the positive relationship between skeletal muscle tissue mass loss and cumulative CO2 evolution suggest that tissue decomposition was most efficient at 2 °C. These phenomena may be due to lower microbial catabolic requirements at lower temperature.  相似文献   
108.
 Biochemical and physiological characteristics of salt-tolerant (88 mM, 264 mM and 440 mM NaCl) strains of Bradyrhizobium were evaluated according to their capacity for using different carbon sources, growth rate, resistance to antibiotics, plasmid profile and exopolysaccharide production. Salt-tolerant strains significantly enhance their capacity to oxidize C sources (about 75–85 compounds) by increasing growth rate and exopolysaccharide production involved in adhesion, resulting in a greater adapting capacity to colonize unfavorable saline environments. However, salt stress could work as a curing agent and thus the gene stability would become critical for the biological nitrogen-fixation information present in plasmids, as is the case in Rhizobium. Received: 5 January 1998  相似文献   
109.
 A new assay, using immunomagnetic separation and uptake of tritiated leucine ([3H]-Leu), was developed for measuring the in situ metabolic activity of specific bacterial populations in soil. Such assays are needed to assess the role individual species play in diverse microbial soil communities. The method was optimized using Pseudomonas putida KT2440 : :Tc+/TOL::gfp inoculated into soil microcosms. Inoculated soil samples were incubated with [3H]-Leu followed by an immunomagnetic separation to recover the target bacteria. Radiolabel incorporated by the target bacteria was then measured. Incubation time with immunomagnetic beads was not critical for optimal target cell recovery, but samples needed to be washed at least 5 times during the immunomagnetic separation to reduce unspecific binding of the indigenous soil bacteria to the magnetic beads. Soil absorption of the polyclonal antibody further reduced this unspecific binding, resulting in <1% contamination by indigenous soil bacteria relative to numbers of recovered target cells. The assay was tested by investigating the effect of different incubation temperatures on the metabolic activity of the target cells. As expected, a linear relationship between activity and temperature was observed, demonstrating the sensitivity of the assay. The method was applied to compare activities of the target strain in bulk soil and in the rhizosphere of barley. Contrary to what was anticipated, no significant difference in metabolic activity was observed. Received: 4 November 1999  相似文献   
110.
为探讨玉米不同种植方式下土壤微生物群落功能多样性的差异,进行田间定点试验,采用Biolog方法分别研究了4行轮作、4行连作、8行轮作和8行连作的种植方式对玉米种植前、拔节期、抽穗期和收获期土壤微生物功能多样性的影响。结果表明:4种种植方式的土壤微生物均在种植前代谢活性最弱、功能多样性最低,在玉米抽穗期土壤微生物代谢活性最强,功能多样性最高。在种植玉米前,轮作的土壤微生物代谢活性和功能多样性高于连作,8行轮作和4行轮作土壤微生物的物种多样性指数分别比相应的连作高22.93%和11.42%;4行轮作的土壤微生物物种多样性指数比8行轮作低3.17%,而4行连作比8行连作高6.83%。在玉米拔节期、抽穗期及收获期连作土壤微生物功能多样性略高于轮作,且有4行连作大于8行连作的趋势,但差异均未达显著水平。种植前,4种种植模式的土壤微生物对6大类碳源的利用程度整体上都较低,降解碳水化合物类、羧酸类和聚合物类碳源的微生物是种植方式影响的主要土壤微生物类群;随着玉米的生长,土壤微生物对6大类碳源的利用都逐渐增强,玉米拔节期、抽穗期和收获期之间土壤微生物特征碳源没有较大差异,4种种植方式的土壤微生物对聚合物类碳源利用程度差异都不显著。PLS-EDA分析结果表明种植方式对土壤微生物产生较大影响,种植前8行轮作和4行连作的土壤微生物碳源利用模式具有相似性;种植玉米后4种种植方式的土壤微生物对碳源的利用模式存在较大差异,其中4行连作的土壤微生物在玉米拔节期和收获期对碳源的利用模式与其他3种种植方式差异最大。试验说明作物长期连作栽培会影响土壤微生物群落功能,降低土壤微生物物种多样性,引起土壤微生物群落结构与功能的失调。  相似文献   
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