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81.
The objective of this study was to elucidate the in vivo effects of the ethanol extract of wooly Glycine tomentella Hayata (GTE) root on tilapia to elucidate whether GTE has antistress activity. Tilapia as an animal model were fed with or without GTE, then injected with lipopolysaccharide (LPS) or ammonium chloride (NH(4)Cl). The tilapia were exposed to 100 mg/L of aqueous NH(4)Cl, and/or acute cold stress. Growth parameters of the tilapia were measured during the feeding trials. Tilapia injected with GTE (20 μg/g of fish), NH(4)Cl (100 μg/g of fish) and/or LPS (1 μg/g of fish) were then sampled 2 h poststimulation. GTE significantly inhibited cyclooxygenase-2 expression and hemoglobin (Hb) dimer formation (36 kDa). GTE also improved growth and blood viscosity and upregulated eicosapentaenoic acid content of erythrocytes. The in vivo results indicated that GTE (20 μg/g of fish) can be applied as a stress-tolerance enhancing agent for the aquaculture industry.  相似文献   
82.
叶枯病对小麦生产危害严重,麦根腐平脐蠕孢菌(Bipolaris sorokiniana)是小麦叶枯病的主要致病菌。为筛选抗B. sorokiniana叶枯病小麦种质,采用“孢子液喷洒、套袋(罩)保湿”接菌鉴定的方法,于2019-2020年对130个小麦品种(系)进行苗期及灌浆期叶枯病抗性鉴定,同时分析了小麦苗期与灌浆期对B. sorokiniana叶枯病抗性的相关性。结果表明,130个小麦品种(系)中,苗期抗病材料占32.3%,其中高抗与中抗材料分别为1.5%与30.8%,无免疫材料;感病材料占67.7%,其中中感与高感材料分别为20.8%与46.9%;灌浆期抗、感叶枯病材料分别占11.5%与88.5%,无高抗材料;小麦苗期与灌浆期对B. sorokiniana叶枯病抗性呈显著正相关关系(r = 0.72)。此结果为抗B. sorokiniana叶枯病的遗传育种与抗病机理研究提供了优异的种质资源;基于苗期抗性与灌浆期抗性的显著相关性,可以通过室内快速准确的苗期叶枯病抗性鉴定预测大田条件下小麦灌浆期的抗性,节省时间,减轻大田鉴定繁重的工作量,并降低环境因素对鉴定结果的影响。  相似文献   
83.
结合历史时期的海水入侵监测数据,对大连市典型海水入侵区大魏家地区50余年海水入侵历史演化过程进行了分析.基于近期地下水采样测试数据,评价了当前地下水供水的生活饮用水和农业灌溉水的适宜性.在此基础上,从自然和人类活动两个方面对该区地下水质情势和影响水质的主控要素进行了分析和判别.结合目前地下水开发利用现状,提出了地下水开...  相似文献   
84.
Anthurium andraeanum is one of the most economically important floral crops and potted flowers marketed worldwide. Microsatellite markers are currently the preferred molecular marker owing to the many desirable attributes, including hypervariability, codominance, and amenability to high-throughput genotyping; however, there are few polymorphic molecular markers available for Anthurium. The object of this study was to develop and characterize novel microsatellite markers using the Araceae sequences in GenBank of the National Center for Biotechnology Information (NCBI) to contribute to molecular identification for cultivar protection. Using 1,579 Araceae expressed sequence tags (ESTs) and the related nucleotide sequences, 100 candidates contained simple sequence repeat (SSR) motifs that were suitable for primer design. Furthermore, 100 pairs of SSR primers were screened against a set of 28 diverse genotypes representing 24 cultivars that included four registration cultivars which were bred from the Taiwan Agricultural Research Institute (TARI) and 20 commercial cultivars, appended with three hybrid progeny and a mutant line. From the selected six polymorphic SSR loci, 52 alleles were amplified and 27 distinct genotypes were found, except for ‘Tropical’ and its mutant, with a mean number of eight alleles per locus. The polymorphism information content (PIC) ranged from 0.86 to 0.93. Based on these results, we proposed a key identification set using four microsatellite markers that is sufficient to discriminate among 24 cultivars. Because the Anthurium microsatellite markers developed in this study are primarily from expressed sequence tags or related genomic sequences, they can be used for cultivar identification and, accordingly, contribute to genetic evaluations in breeding programs.  相似文献   
85.
For the understanding of contaminant transport and transformation through landfill liner soils, most models are proposed with one-dimensional solutions. However, for large-scale contamination analysis, the one-dimensional analytical equations are not valid owing to the restriction of contaminants moving in horizontal direction. Thus, semi-analytical solutions for two-dimensional transport and transformation of contaminants through soil media with the consideration of large-strain deformation have been developed. To achieve this, Gibson’s large-strain consolidation theory is applied to capture the deformation of soil media under loading, with self-weight effects being taken into account. Transport and transformation of dissolved or sorbed contaminates in fully saturated finite soil medias are captured by extending a well-developed advection-dispersion model in two-dimensional space. The proposed analytical solutions are validated through simulating the process of coupled transport-transformation process of contaminants and consolidation of a finite soil layer. Profiles of contaminant concentration for different cases have been compared and discussed. The resulting simulation shows that large-strain deformation would restrict the transport and transformation of contaminants significantly, in both horizontal and vertical directions. Parameter studies also indicate that, with the increasing depth of soil layer, the breakthrough time for contaminants increases dramatically; diffusion coefficients affect the two-dimensional distributions of contaminant concentration and fate of contaminant in layered soil significantly. The numerical findings of this study can provide proper suggestions for the design of landfill liners.  相似文献   
86.
The antioxidant properties of water extracts from Cassia tora L. (WECT) prepared under different degrees of roasting were investigated. The water extracts of unroasted C. tora L. (WEUCT) showed 94% inhibition of peroxidation of linoleic acid at a dose of 0.2 mg/mL, which was higher than that of alpha-tocopherol (82%). Water extracts prepared from C. tora L. roasted at 175 degrees C for 5 min and at 200 degrees C for 5 min exhibited 83% and 82%, respectively, inhibition of linoleic acid peroxidation. This result indicated that the antioxidant activities of WECT decreased with longer roasting time or higher roasting temperature. The IC(50) of WEUCT in liposome oxidation induced by the Fenton reaction was 0.41 mg/mL, which was higher than that of alpha-tocopherol (IC(50) = 0.55 mg/mL). WEUCT also exhibited good antioxidant activity in enzymatic and nonenzymatic microsome oxidative systems. The water extracts of roasted C. tora L. increased in the degree of browning and produced chemiluminescence when compared with the unroasted sample. However, the total polyphenolic compounds of WECT decreased after the roasting process finished. In conclusion, the decrease in the antioxidant activity of water extracts from roasted C. tora L. might have been due to the degradation of Maillard reaction products and the decrease of polyphenolic compounds.  相似文献   
87.
比较了X分离冻精和未分离冻精与牛卵母细胞进行体外受精后,受精卵的卵裂率和胚胎发育率。X分离冻精组受精卵的卵裂率(51.4%)和囊胚发育率(19.7%)显著低于未分离冻精组(67.9%,29.9%,P〈0.05);微量上浮非离心法处理X分离冻精和未分离冻精后,其受精卵的卵裂率(50.7%,65.5%)高于上浮离心法处理组(48.3%,63.8%),但两种处理方法之间无统计学差异(P〉0.05);同一种精子采用微量上浮非离心法或上浮离心法处理后,其卵裂胚的桑葚胚发育率和囊胚发育率无统计学差异(P〉0.05);X分离冻精的受精卵与颗粒细胞和睾丸支持细胞共培养后,其卵裂率(50.0%,51.4%)与非共培养组(50.3%)无显著差异(P〉0.05);两个共培养组的桑葚胚发育率(53.3%,54.6%)和囊胚发育率(21.1%,21.5%)均高于对照组(52.2%,20.4%),但无统计学差异(P〉0.05)。  相似文献   
88.
奶牛乏情是指产后60~90 d没有发情表现的经产奶牛及14~18个月龄不发情的育成牛,机体不表现出任何明显的发情状态,导致卵泡发育不良,从而影响机体排卵,引起发情周期紊乱、妊娠推迟,这对奶牛业的发展产生重大的影响。本文主要综述奶牛出现乏情状态的繁殖性疾病的研究状况,为进一步研究奶牛产后乏情提供理论依据。  相似文献   
89.
土壤施钙对设施栽培油桃果实钙含量及品质的影响   总被引:4,自引:1,他引:4  
以设施栽培的“曙光”油桃为试材,研究了土壤施Ca(NO3)2和CaSO4对油桃产量和品质的影响。结果表明,在一定施钙水平范围内,随施钙量的增加,设施油桃果实单果重、产量、钙含量、可溶性糖含量、果实硬度、Vc含量均呈显著性增加,土壤施Ca(NO3)2和CaSO4量分别为120和160 g/plant时达到最佳施肥效果; 土壤施Ca(NO3)2和CaSO4可显著降低设施油桃果实裂核率,并均在施钙量为200 g/plant时达到最低,分别为36.1%和38.3%。不同钙肥和施钙水平对油桃果实可滴定酸含量均无显著影响,可滴定酸含量在0.43%~0.45%间波动。 关键词: 设施栽培; 油桃; 钙; 品质  相似文献   
90.
【目的】研究土壤呼吸排放特征及其影响因素是评价土壤碳平衡的基础。本课题组前期研究发现在地表下35 40 cm处埋设作物秸秆隔层结合地表地膜覆盖,具有明显的耕层控抑盐效果。但由于秸秆隔层结合地膜覆盖调控土壤微环境,可能影响土壤CO2的排放。然而,相关研究特别是基于野外试验的研究还比较缺乏,不利于正确评价该技术措施的综合效应。为此本研究拟通过相关试验揭示不同耕作方式对河套灌区盐渍化土壤呼吸的影响。【方法】本文以位于河套灌区实施秸秆深埋三年后的典型盐碱地农田为研究对象,观测研究地膜覆盖结合秸秆深埋条件下盐渍化土壤呼吸及温度、水分、盐分、有机质等影响因素的动态变化。该研究主要分析翻耕(CK)、翻耕结合地膜覆盖(PM)、上盖地膜下埋秸秆(PM+SL)和秸秆深埋(SL)4种耕作措施下盐渍化土壤呼吸速率的动态变化及其与影响因素的关系。【结果】1)4种耕作方式的土壤呼吸速率在食葵全生育期内均呈降低趋势,PM+SL处理在整个生育期内土壤呼吸速率最高,PM次之,SL处理呼吸速率仅在蕾期较CK略高,其余时期与CK基本持平,在盛花期、成熟期10:00和15:00两个关键时间点各处理间土壤呼吸值同样表现为:PM+SLPMSLCK;各耕作方式0—40 cm土壤温度变化趋势保持一致,仅在收获期出现差异;PM+SL处理0—40 cm土壤含水量在所有处理中均为最低值,但其在控盐和增加有机质上明显优于其它处理;2)土壤呼吸速率与0—40 cm土壤温度呈极显著的正相关关系(P0.01),与0—40 cm土壤水分、盐分、有机质含量无相关性。拟合方程显示盐渍化土壤呼吸受土壤温度、水分、盐分的综合效应影响。【结论】干旱区域盐渍化土壤的呼吸速率受土壤温度、水分、盐分等因素的综合影响,在该区域通过上盖地膜下埋秸秆等相应措施起到保温抑盐效果的同时,可增强食葵根系生长以及微生物的代谢活动。  相似文献   
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