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101.
琴萌春王13号是从日喀则地方品种中选育出的自交不亲和系87-6-9与从秦白2号中选育出的自交不亲和系93-7-5配制的春结球大白菜一代杂种。生育期60d(天),外叶绿色,叶柄白绿色,叶球短圆筒形、下部稍细,叠抱,纵径22·2cm,横径20.0cm,单球质量1.5kg,每667m2净菜产量3610.6kg。抗霜霉病、病毒病和软腐病,结球迅速,品质好,冬性强,春播不易抽薹,适宜喜欢叠抱类型大白菜的地区作春、秋两季栽培。  相似文献   
102.
龙粳13号是黑龙江省农业科学院水稻研究所于1995年以龙花91-340为母本,空育139为父本进行有性杂交,1996年接种其F1代花药离体培养选育而成。该品种具有抗瘟性强、熟期早、米质优、丰产、适应性广等特点。  相似文献   
103.
The non-extractable residues of the fungicide cyprodinil formed in heterotrophic cell suspension cultures of wheat were studied by application of [2-pyrimidyl-14C] or [2-pyrimidyl-13C]cyprodinil. The main objective was to examine whether solid-state and liquid 13C NMR spectroscopy can be used to examine plant bound residues of pesticides. For 14C experiments, wheat suspensions grown on glucose as carbon source were treated with 10 mg litre(-1) of 14C-cyprodinil. After incubation for 12 days, 20% of applied 14C was detected as non-extractable residues. The cell debris were treated with 0.1 M HCl (reflux), 1.0 M HCl (reflux), buffer, or 2 M NaOH (50 degrees C); Bj?rkman lignin and acidolysis lignin fractions were also prepared from the debris. Radioactivity liberated and solubilized by these procedures was examined by thin-layer chromatography and high-performance liquid chromatography. The results showed that cyprodinil and primary metabolites contributed to the fungicide's bound residues. Most of the residues (12% of applied 14C) remained associated with polar or polymeric/oligomeric endogenous cell materials in a stable manner. For the study with 13C-cyprodinil, wheat suspensions were cultivated on 13C-depleted glucose for four growth cycles, resulting in maximum 13C depletion of the natural cell components to about 0.10%. During the fourth cycle, 13C-labelled cyprodinil was applied, and cells were incubated (12 days). Cell debris was prepared and examined by solid-state 13C NMR spectroscopy. Debris was then treated as described above in the 14C experiment. Solubilized fractions were analyzed by liquid 13C NMR spectroscopy. However, none of the 13C NMR spectra recorded gave utilizable or unambiguous results, and all exhibited large inconsistencies, especially concerning the data from the conventional 14C experiment.  相似文献   
104.
Leaf shapes are not only the useful indicators in plant taxonomy,but also the important factors affecting energy and material exchange in leaves.In this paper,we collected and scanned the leaves of Nitraria tangutorum in Dengkou of Inner Mongolia Autonomous Region(the mean annual precipitation 145 mm) and Minqin of Gansu Province (the mean annual precipitation 115 mm) and N. sphaerocarpa in Dunhuang,and then analyzed leaf shape parameters with Image - Pro Plus6.0 image processing software and leafδ13C values in the isotope laboratory of the Chinese Academy of Forestry.The result showed that:1) as leaf area increased with increasing water availability the increases in the leaf length and width were asynchronously;2) with the same leaf width,the 1 eaves of N.tangutorum and N.sphaerocarpa were significantly longer in high water available conditions;and 3) although there were significantly differences in water availability between Dengkou and Minqin,as well as between the bottom and middle of the alluvial fan near the East Lake in Dunhuang,the leafδ13C values of N.tangutorum or N.sphaerocarpa were similar in different water conditions(P>0.05).Our results suggested that the ratio of leaf perimeter to area would be an important factor which linked leaf shape to plant water physiology.During growing procedure of leaf area,leaf length increase was prior to its width to alleviate the reduction in ratio of perimeter to area and maintain water use efficiency of the plant.  相似文献   
105.
陆地棉MADS-box基因GhMADS13的功能分析   总被引:1,自引:0,他引:1  
为了研究GhMADS13的功能,利用NCBI上提交的序列设计引物进行PCR扩增,扩增序列与提交序列的ORF (Open reading frame)的一致性为100%.qRT-PCR结果表明:棉花的各个组织中,GhMADS13在花中的表达量最高,是表达量低的根的几百倍;花器官中GhMADS13在萼片、花瓣、雄蕊、心皮和胚珠中都有表达,表达量虽有差异,但差异不大,其在胚珠中的表达量最高.将GhMADS13插入到pBI121载体上,构建了植物超表达载体.通过浸花法转化拟南芥,获得了2个转基因株系,分子检测和表型数据统计的结果表明GhMADS13的转录水平越高植株越矮小,角果的长度越短,种子的数目越少.根据GhMA DS13的qRT-PCR结果和异位表达分析,推测GhMADS13主要抑制胚珠的发育.  相似文献   
106.
测定了茂兰喀斯特森林内的荔波野生梅(Prunus mume Sieb.et Zucc)叶片的δ13C值,同时对不同生境的荔波野生梅叶片的δ13C值进行比较,结果表明,荔波野生梅叶片δ13C值的范围为-29.43‰~-26.50‰,平均值为-28.00‰±0.71‰,比典型的亚热带植物要高,δ13C值变化范围也较亚热带地区更大,但与报道的喀斯特山区植物的叶片δ13C值相近;不同生境的荔波野生梅叶片δ13C值存在显著差异,石面和石缝生境的平均值显著低于土面生境的平均值,但石面和石缝生境间不存在显著差异;土壤的含水量对植物叶片δ13C值的高低有较大的影响,它们之间呈显著的负相关,R值为-0.72.  相似文献   
107.
秸秆碳对不同施肥水平低肥力土壤碳组分的影响   总被引:1,自引:0,他引:1  
为探明不同施肥水平下秸秆碳对低肥力土壤溶解性有机碳(DOC)、微生物量碳(MBC)和颗粒有机碳(POC)含量的影响,采用碳化硅管原位法,向不同施肥水平(0、120、240 kg·hm-2,以纯氮计)的低肥力土壤添加13C标记小麦秸秆,定期取土样测定不同有机碳组分的含量及其δ13C值,并计算秸秆碳在各有机碳库中的转化及贡献比例。研究结果显示,秸秆添加后7 d是快速转化阶段,此后秸秆碳转化渐缓,以向POC转化为主。相较于DOC,秸秆碳更倾向转化为MBC和POC,秸秆添加60 d后的转化比例分别为0.12%~0.38%、4.01%~6.25%和4.74%~9.54%。秸秆添加后,土壤DOC、MBC和POC含量均显著增加,来自于秸秆碳的贡献分别为0.29%~15.01%、13.20%~32.85%和33.62%~59.69%。相较于0、240 kg·hm-2的施氮处理,施氮量为120 kg·hm-2时,秸秆添加能同时大幅提高试验土壤的活性和缓效性有机碳库含量。由此表明,秸秆还田条件下,适量施加氮肥更有利于低肥力土壤的培肥与固碳。  相似文献   
108.
【目的】解析光合产物在马尾松幼苗植株中的运输和分配规律,揭示马尾松生产力形成过程,为探讨不同环境干扰下马尾松光合产物分配过程的变化提供参考依据。【方法】采用 13 C同位素脉冲标记法,对1.5年生马尾松幼苗进行标记,标记结束后第0、2、5、17、24、72、120、168、216和 360 h ,按不同部位对马尾松幼苗进行全收获取样,测定 13 C含量,以监测近期合成的光合产物在马尾松幼苗中的运输和分配规律,同时测定光合产物全碳、非结构性碳水化合物(NSC)在各个器官的积累量。【结果】1)标记的光合产物在针叶中合成后,向各库器官的运输量随着时间延长由多逐渐减少,具体表现为标记结束后0~24 h内最多,24~216 h逐渐减少,216 h之后运输完成,且59%以上标记的光合产物在0~24 h内运输到各库器官。2)光合产物运输趋于稳定后,在各器官的分配大小依次为1年生叶>当年生叶>根>茎干>1年生枝>当年生枝,与生物量的分配大小一致,但与库活力大小不同,其库活力依次为当年生叶>当年生枝>1年生叶>根>1年生枝>茎干。3)各器官全碳和NSC积累量的分配与近期合成光合产物的分配大小一致,依次为1年生叶>当年生叶>根>茎干>1年生枝>当年生枝。【结论】马尾松幼苗光合产物运输速率大于0.1 m ·h -1 ,59%以上标记的光合产物在合成后的0~ 24 h 内完成向各个库器官输出。新合成的光合产物在各器官中的积累量表现为功能器官(叶和根)居多,这一分配规律有利于马尾松幼苗阶段的生长。  相似文献   
109.
陕西关中地区肉牛产地同位素溯源技术初探   总被引:3,自引:1,他引:2  
为应用牛组织中C、N同位素组成的区域分布和同位素指标溯源肉牛产地,本文利用同位素比率质谱仪(IRMS)对陕西关中不同区县来源的牛尾毛样品的1δ3C和1δ5N值进行检测,通过聚类分析,研究陕西关中地区肉牛组织中同位素组成的区域分布情况。结果表明,杨凌区、眉县牛尾毛样品聚为一类;乾县、永寿县样品聚为一类;麟游县样品聚为一类;扶风县、岐山县和凤翔县分类不十分明显,分散在上述3类中。说明陕西关中不同地区肉牛组织中同位素组成存在差异,利用它们可进行肉牛地域的小范围溯源。  相似文献   
110.
AIM: To investigate the regulation of miR-222 on BCL2L13 gene and its effect on the growth and apoptosis of HBx-HepG2 cells, and to explore the underlying molecular mechanisms. METHODS: The expression level of miR-222 was detected by RT-qPCR. The HBx-HepG2 cell growth was examined by MTT and colony formation assays. The cell cycle and apoptosis were analyzed by flow cytometry. The recombination vector pmirGLO-BCL2L13 was constructed, and dual-luciferase reporter experiment was performed to validate the target of miR-222. RESULTS: The expression level of miR-222 in the HBx-HepG2 cells was significantly higher than that in the L02 cells (P<0.05). Over-expression of miR-222 enhanced HBx-HepG2 cell growth, changed cell cycle, and inhibited apoptosis (P<0.05). Knockdown of miR-222 reduced HBx-HepG2 cell growth, changed cell cycle, and increased cell apoptotic rate (P<0.05). BCL2L13 was down-regulated in the HBx-HepG2 cells as compared with L02 cells (P<0.05), and knockdown of miR-222 in the HBx-HepG2 cells increased the expression level of BCL2L13 (P<0.05). The results of dual-luciferase reporter assay and restore experiment showed that miR-222 negatively regulated the expression of BCL2L13 via targeting 3'UTR of BCL2L13, resulting in the promotion of HBx-HepG2 cell growth. CONCLUSION: miR-222 enhances HBx-HepG2 cell growth via down-regulation of BCL2L13.  相似文献   
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