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101.
102.
Fei Zhang Sumei Chen Fadi Chen Weimin Fang Yanming Deng Qingshan Chang Pusheng Liu 《Euphytica》2011,177(1):15-24
The inheritance of two flowering traits of chrysanthemum, initial blooming time and the duration of flowering, was investigated
using segregation within an F
1 population derived from a cross between the autumn-flowering ‘Yuhualuoying’ and the summer-flowering ‘Aoyunhanxiao’ cultivars.
The analysis, based on a single segregating generation and the major gene plus polygene mixed inheritance model, showed that
the inheritance of both traits was compatible with the presence of two pairs of major genes displaying additivity–dominance–epistasis,
with additivity predominating. As the heritability of both pairs of major genes was high (initial blooming time ~65%, duration
of flowering ~72%), it should be possible to select for both traits in early breeding generations. A marker-trait association
analysis based on sequence-related amplified polymorphism (SRAP) genotyping uncovered 10 (initial blooming time) and 12 (duration
of flowering) markers significantly associated with phenotype, cumulatively explaining, respectively, 46 and 54% of the variation.
Some potentially useful markers were identified. 相似文献
103.
Effect of nitrogen root zone fertilization on rice yield,uptake and utilization of macronutrient in lower reaches of Yangtze River,China 总被引:1,自引:0,他引:1
Xiaowei Liu Huoyan Wang Jianmin Zhou Zhaoming Chen Dianjun Lu Dejin Zhu Pingliang Deng 《Paddy and Water Environment》2017,15(3):625-638
Improper application of nitrogen (N) has led to high N losses and low N use efficiency in the lower reaches of Yangtze River in China. An effective method to solve such problems is the deep fertilized N in root zone (RZF). Limited information is available on the effect of RZF on the uptake of macronutrients (N, P and K) and rice yield. Field experiments, conducted from 2014 to 2015, compared the farmer fertilizer practice (FFP, with 225 kg ha?1 of N, split into three doses) and RZF using the same rate but placing N 5 cm away from rice roots in holes 10 cm deep (RZF10) or 5 cm deep (RZF5) as a single application. The highest mean yield (10.0 t ha?1) was obtained in RZF10, which was 19.5% more than that in FFP. Root zone fertilization of urea (whether 10 cm deep or 5 cm deep) resulted in greater accumulation of N, P and K in stem, leaf sheaths, leaf blades and grains compared to that in FFP in sandy and in loam soils. The uptake of N, P and K was the highest in RZF10 (average at 176.7, 66.2 and 179.1 kg ha?1, respectively), higher than that in FFP by 45.0, 17.0 and 22.6%, respectively. N apparent recovery efficiency was markedly higher in RZF10 (53.1%) than in FFP (27.5%). RZF10 significantly increased the N, P, K uptake compared with FFP under different N rates in both sandy and loam soils. These results suggest that the N, P and K input amount should be re-determined under RZF. 相似文献
104.
105.
海涂海水灌溉对鲁梅克斯植物生长的影响 总被引:6,自引:0,他引:6
为高效持续利用海水与滨海盐土资源,缓解海水养殖废水直接排放对海洋的污染,课题组从1995年开始,收集、引进和筛选了一些具有经济开发前景的耐盐植物,对其生物学、生态学特性进行了研究[1],并在我国海南乐东、江苏大丰、山东莱州三个典型气候带海涂进行海水灌溉试验,探索海水灌溉对耐盐植物生长发育、滨海盐土演变的影响及其对海水养殖废水的净化能力.本文仅就山东莱州田间小区海水灌溉鲁梅克斯(Rumex patientiax R. Tianschanicus, cv. Rumex K-1)的试验结果进行讨论. 相似文献
106.
107.
棉田枯萎病发病率和严重度,用肾形线虫(Rotylenchulusreniformis)和枯萎菌联合接种比单接枯萎菌显著提高,且病情增长块,土壤中肾形线虫数量也较单接肾形线虫高。说明棉花枯萎病与肾形线虫有协生现象,感病品种更明显。用联合接种法对棉花新品系B013-2和B023-11进行兼抗性鉴定,二者均属耐病类型。 相似文献
108.
基于气体超声流量计的应用现状,分析了其实现远程诊断功能的重要意义,列举了其核心诊断指标:流速特性、声速特性、声道信号质量、声道增益值、声道信噪比。讨论了远程诊断系统的设置需求,其功能体现在可实时地对现场计量站内的超声波流量计、流量计算机、压力变送器、温度变送器及气相色谱分析仪等设备进行运行状态的指示、诊断及远程管理。在中亚天然气管道的应用实践表明:气体超声流量计远程诊断可以及时地将流量计的工作状况通知运行操作人员,从而对流量计进行有效监控,及时采取预防措施,降低计量故障的发生概率,提高运行效率,降低运营成本。(表3,图5,参6) 相似文献
109.
J. Deng X. Wu S. Bin T.‐J. Li R. Huang Z. Liu Y. Liu Z. Ruan Z. Deng Y. Hou Y.‐L. Yin 《Journal of animal physiology and animal nutrition》2010,94(2):220-226
Experiments were conducted to determine the effects of feeding different starch sources on piglets. Four diets were formulated with maize, brown rice, sticky rice and Hi‐Maize 1043 as starch sources, with resistant starch (RS) contents of 2.3%, 0.9%, 0.0%, 20.6%, and amylose and amylopectin ratio of 0.23%, 0.21%, 0.18%, 0.06% respectively. Fifty‐six pigs weaned at 28 days of age were randomly assigned to one of the four diets. In Exp. 1, six piglets in each group were fitted with an indwelling jugular catheter. After 25 days of feeding trial, venous blood samples were obtained at time zero and every 1 h for 4 h. In Exp. 2, the remaining piglets were used to determine the effects of different starch sources on the fractional synthesis rate (FSR). The results indicated that feeding the Hi‐Maize 1043 diet decreased (p < 0.05) plasma contents of glucose, insulin, lactic acid and T3, while sticky rice increased plasma contents of glucose and insulin. The insulin contents in piglets fed the sticky rice diet was 69.2 μIU/ml at 1 h post‐feeding which was highest among the starch diets. The FSR in the pancreas, spleen, duodenum, jejunum, ileum and colon in the corn group were much higher (p < 0.05) than that in the sticky rice group. These results suggest that RS is potentially beneficial for improving insulin sensitivity in young pigs and that the ratio of amylose and amylopectin have significantly effects on the FSR in splanchnic tissues in weaned piglets. Another finding of this study indicated maize with a ratio of amylose and amylopectin of 0.23 has the best starch sources for pig production. 相似文献
110.
采集了城关、松柏、桃川、允山、夏层铺5个植烟乡镇的104个土壤样品,研究了江永植烟土壤有效锰含量及其影响因素,为改良江永植烟土壤和烟区的可持续发展提供理论依据。研究结果表明:江永县植烟土壤有效锰含量适中,均值为19.56 mg/kg,变幅为3.80~93.80 mg/kg,变异系数达到93.30%,有效锰含量处于适宜范围的样本比例为49.04%。土壤有效态锰含量会随pH、有机质、全磷、全氮含量升高而降低。4个影响因素pH、有机质、全磷、全氮中,尤以有机质含量对土壤有效锰含量影响最大。 相似文献