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101.
102.
【目的】 研究马的行为规律及变化过程,为马匹的选择、训练及健康评估等提供理论参考。【方法】 选取健康状况良好的伊犁马母马12匹,采集视频数据,记录马匹在各时间段摄食、静息、探究、修饰、排泄和其他等各种行为指标,比较分析各时段行为的差异性。【结果】 舍饲伊犁马在行为规律上全天时间摄食>静息>探究>其他>修饰,不同时段伊犁马行为时间分配上,咀嚼、伸展时间下午时间段极显著大于早、晚时间段(P<0.01),卧息、站息时间晚上极显著大于早上、下午时间段(P<0.01),站立、警觉时间早上、下午时间段均极显著大于晚上时间段(P<0.01),舔食时间早上时间段极显著大于晚上时间段(P<0.01),啃痒时间早上时间段极显著大于下午时间段(P<0.01),频次指标中,咀嚼次数下午时间段极显著大于晚上时间段(P<0.01),显著大于早上时间段(P<0.05),舔食、摇头次数早上时间段极显著大于晚上时间段(P<0.01),卧息次数晚上时间段均极显著大于早上、下午时间段(P<0.01),警觉、站立次数早上、下午时间段均极显著大于晚上时间段(P<0.01),啃痒、伸展早上时间段显著大于下午时间段(P<0.05),排便次数早上、下午、晚上各时间段均存在极显著差异(P<0.01)。【结论】 舍饲伊犁马全天中用于摄食的时间最长,其后依次是静息、探究、其他、修饰。咀嚼、舔食多集中在早上、下午各时间段;蹭痒多集中在早上时间段;卧息、站息、伸展多集中于晚上时间段;站立、警觉在白天各时间段均较集中;在嗅探、蹭痒、哈欠、刨地、抬蹄、排尿上没有发现差异,通过观察不同时段所表现的行为指标对马匹行为进行监测,可为实际生产过程中马匹的管理提供客观参考指标,减少对马的伤害,防止恶癖的发生。 相似文献
103.
【目的】 研究新疆昭苏地区伊犁马发情周期内卵泡发育变化规律,分析年龄、温度、膘情对伊犁马母马卵泡发育的影响,为掌握伊犁马母马卵泡发育规律提供理论依据。【方法】 选取伊犁哈萨克自治州昭苏县康苏马业配种站内,同一草场放牧情况下84匹母马作为研究对象监测发情期内卵泡发育,分析对比不同年龄、温度、膘情对伊犁马卵泡发育时长的差异性。【结果】 年龄Ⅱ组TF3-F5显著高于年龄Ⅲ组(P<0.05)。年龄Ⅱ组TF4-5显著高于年龄Ⅲ组(P<0.05)。平均高温对TF1-F2具有显著影响(P<0.05),平均高温Ⅰ组TF1-F2显著高于平均高温Ⅱ组(P<0.05)。平均低温对TF1-F2具有极显著影响(P<0.01),平均低温Ⅰ组TF1-F2极显著高于平均低温Ⅱ组(P<0.01)。积温对TF1-F2具有显著影响(P<0.05),积温Ⅱ组TF1-F2极显著高于积温Ⅰ组(P<0.01)。膘情对TF1-F2、TF3-F4、TF1-F5、TF2-F5、TF3-F5均具有极显著影响(P<0.01),对TF2-F3具有显著影响(P<0.05)。膘情Ⅰ组TF1-F2极显著高于膘情Ⅲ组(P<0.01)。膘情Ⅰ组TF2-F3显著高于膘情Ⅲ组(P<0.05)。膘情Ⅲ组TF3-F4极显著低于膘情Ⅰ组(P<0.01),膘情Ⅲ组TF3-F4显著低于膘情Ⅰ组、膘情Ⅱ组(P<0.05)。膘情Ⅰ组TF1-F5极显著高于膘情Ⅱ组、膘情Ⅲ组(P<0.01),膘情Ⅱ组TF1-F5显著高于膘情Ⅲ组(P<0.05)。膘情Ⅰ组TF2-F5极显著高于第Ⅲ组(P<0.01),膘情Ⅰ组TF2-F5显著高于膘情Ⅱ组、膘情Ⅲ组(P<0.05)。【结论】 年龄、温度、膘情均一定程度的影响伊犁马母马的卵泡发育,其中膘情对卵泡发育有极显著影响,体况较差可抑制母马卵泡发育。 相似文献
104.
为了解近年来黄淮冬麦区旱地组小麦品种抗旱性的整体情况,对2017—2019年黄淮冬麦区132个区试品种(系)在干旱胁迫下的产量及抗旱指数,穗数、穗粒数、千粒重、株高等性状及抗旱系数,进行分析总结。结果表明:黄淮旱肥组、旱薄组、北部组区试品种(系)近年来品种的抗旱性趋势大体相同,胁迫情况下产量总的变化是旱肥组>旱薄组>北部组,且呈逐年稳中有升的趋势,从抗旱指数看,黄淮旱地小麦品种的抗旱整体还处于偏弱的水平;抗旱性状表现为干旱胁迫下均有不同程度的受损,均以千粒重的受损程度最小,有效穗、穗粒数、株高受损程度最大。 相似文献
105.
106.
The effects of aging from t = 0–108 h at two different temperatures (4 and 25 °C) on the non-linear viscoelastic rheological properties and secondary protein structure of hard wheat flour dough (HWD) were investigated using large amplitude oscillatory shear tests (LAOS) coupled with Fourier transform infrared spectroscopy (FTIR) and SDS-PAGE. Storage (G') and loss (G'') moduli rapidly decreased during aging at 25 °C. Subjecting HWD to progressively longer aging times at 25 °C caused dramatic changes in the non-linear viscoelastic properties demonstrated by strain softening (negative values of e3/e1) and shear thinning (negative values of v3/v1) behavior. Elastic Lissajous curves of the unaged control dough showed clockwise turn and wider elliptical trajectories as dough aging proceeds especially at higher temperatures. Other non-linear LAOS parameters (G'M-G''L, η'M-η'L, S and T) supported that aging process at higher temperature caused a progressive change in dough structure from strain stiffening to strain softening behavior while dough samples aged at 4 °C showed fairly close behavior with the control dough sample. FTIR spectra indicated that the relative content of β-sheet and β-turn structures decreased while the content of α-helix structure increased for all dough samples as a result of dough aging. SDS-PAGE results supported the breakdown of high molecular weight (HMW) and low molecular weight (LMW) glutenin subfractions. Aging at the higher temperature of 25 °C decreased the HMW/LMW ratio from 0.77 to 0.59, while the ratio was 0.73 for the dough aged at 4 °C which is fairly close to the control sample. Our results show that the degradation rate of gluten/starch network was triggered by aging at higher temperature, longer aging time, and natural fermentation which resulted in increasing acidity and increase in endogenous proteolytic and amylolytic activity, and also increasing gluten solubility and break down of intermolecular disulfide bonds at acid pH. 相似文献
107.
In this study, sixteen wheat varieties for cultivation in China were examined for the flour characteristics using the farinograph, extensograph and rheofermentometer, uniaxial extensional rheology employing the extensograph and the Kieffer extensibility rig and biaxial extension by uniaxial compression of mixed dough with and without yeast, rested and fermented dough, and steamed bread quality including specific volume and texture properties. Three statistical analysis methods including Pearson correlation, principle component and stepwise multiple regression analysis were carried out to correlate dough properties with steamed bread quality. Biaxial extension viscosity was positively correlated with texture properties (hardness and chewiness) of steamed bread (r = 0.521–0.685, p < 0.05). Based on the correlation coefficients and the model (r2 = 0.852, p = 0.003) obtained using stepwise multiple regression analysis, the best predictors for specific volume of steamed bread were the maximum resistance to extension of rested dough (r = 0.664, p < 0.01) and total work for breakage of fermented dough (r = 0.662, p < 0.01). Principal component analysis of rheological properties of fermented dough and flour characteristics provided more useful information for discriminating wheat flour quality and help breeders to select most convenient wheat flour for the steamed bread making. 相似文献
108.
Wheat bran is the main by-product during wheat flour processing. Although wheat bran is rich in the bioactive compounds and antioxidant capacity, it is not widely utilized in its natural state. To improve the antioxidant and nutritional properties of wheat bran, a dominant strain, Enterococcus faecalis M2, was screened from lactic acid bacteria (LAB) isolated from various foods. Following solid state fermentation, the soluble dietary fiber content of wheat bran nearly quadrupled compared to the raw material. Total proportion of phenols, flavonoids, alkylresorcinols, along with the antioxidant capacity and free radical scavenging rate were significantly improved, particularly the ferulic acid content increased by 5.5 times. Additionally, the free amino acid content increased with degradation of wheat bran protein, whereas the level of anti-nutrient phytic acid decreased. The results of this study could provide an effective method for biological modification of wheat bran, which further enhance the health benefit and utilization of bran. 相似文献
109.
Wheat is one of the three most widely grown grain crops and the most consumed in Europe. Wheat contains different phenolic compounds, mainly phenolic acids and flavonoids that are not evenly distributed in the wheat, being most abundant in the bran. These phenolic compounds are antioxidants against free radicals and other reactive oxygen species. Therefore, over the last few decades, there is a great interest to study and quantify these compounds present in wheat.This work proposes a HPLC-DAD method that allows a good separation of different phenolic compounds occurring as soluble free and insoluble bound compounds in wheat brand and flour. The extraction and the chromatographic conditions allowed the characterization of forty-two phenolic compounds, among phenolic acids (HBA, HCA, DFA and TFA), phenolic aldehydes, phenolic alcohols and flavonoids (flavones). This method is simple, sensitive, reproducible and accurate, and only a HPLC-DAD equipment is required. Thirty-four soluble and insoluble phenolic compounds can be quantified in wheat flour and brand. Hydroxytyrosol, a potent antioxidant compound, has been identified and quantified in wheat for the first time. 相似文献
110.
To overcome the cost and expense of milling and baking hundreds of samples in wheat breeding programs, cereal chemists have developed various rapid predictive tests for end-use quality assessment. In this study, five small-scale rapid tests, including Solvent Retention Capacity (SRC) and Swelling Index of Glutenin (SIG), were compared for viability and accuracy to determine end-use quality using small quantities of flour. The tests were applied on commercial hard red spring and hard red winter wheat cultivars from two of the three main production regions in South Africa. Rheological and bread-baking characteristics were related to results of the rapid tests. Highly significant cultivar differences were seen for all rheological and baking-related characteristics, and SRC and SIG parameters, with a strong genotype effect. The environment effect was also highly significant across regions, especially for flour protein content (FPC), which affected the rheological and baking-related characteristics differently across the regions. Correlations among SRC, SIG, rheological, and baking quality-related parameters were highly significant, but inconsistent for the two production regions. Only lactic acid SRC and SIG correlated consistently with the rheological and baking quality-related characteristics in both production regions. 相似文献