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81.
目的:克隆北柴胡中可能参与柴胡皂苷生物合成的细胞色素P450酶基因,构建其过量表达载体,为通过转基因验证其功能奠定基础。方法:在454高通量测序获得5'和3'端部分cDNA序列的基础上,利用LD-PCR方法获得全长cDNA,根据全长cDNA序列设计含有酶切位点的PCR引物,利用高保真酶,以RNA反转录产物为模板PCR扩增细胞色素P450酶基因的开放读框,扩增产物与pEASY-T1 Simple载体连接,转化大肠杆菌DH5α;重组质粒pT1-P450经菌液PCR和酶切方法验证后测序,采用NCBI在线Blastx、DNAman和MEGA4软件对序列进行生物信息学分析,随后将pT1-P450的酶切产物插入双元载体pCAMBIA-SUPER 1300,菌液PCR和酶切验证重组质粒p1300-P450。结果:扩增到了北柴胡细胞色素P450酶基因BcCYP87E,构建了这一基因的过量表达载体。结论:细胞色素P450酶基因的克隆和转基因载体的构建,为后续开展转基因研究,验证其生物功能奠定了基础。  相似文献   
82.
A rapid, sensitive, and specific method by high‐performance liquid chromatography (HPLC) coupled to diode‐array detection (DAD) and tandem mass spectrometry (MS) techniques was developed for the identification of absorbed constituents and their metabolites in rats after the oral administration of a Chai‐Huang decoction (CHD), which consists of Bupleurum chinense and Scutellaria baicalensis in the proportion 1 : 1 (w/w). By comparing their retention times and MS data with those of authentic compounds and published data, a total of 14 compounds were identified in the CHD samples. In addition, eleven and seven compounds were characterized in the urine and serum samples of the rats, respectively. The results indicated that the main absorbed constituents were chrysin‐6‐C‐arabinosyl‐8‐C‐glucoside, chrysin‐6‐C‐glucosyl‐8‐C‐arabinoside, baicalin, wogonin‐5‐O‐glucoside, oroxylin A‐7‐O‐glucuronide, wogonoside, saikosaponin A, saikosaponin C, saikosaponin D, baicalein, and wogonin. These compounds might be responsible for the curative effects of the CHD. The findings demonstrated that the proposed method could be used to rapidly and simultaneously analyze and screen the multiple absorbed bioactive constituents in a formula of traditional Chinese medicines (TCM). This is very important not only for the pharmaceutical discovery process and the quality control of crude drugs but also to explain the mechanisms of action of TCM.  相似文献   
83.
鹅掌楸的花部数量变异与结实率   总被引:14,自引:1,他引:13  
濒危植物鹅掌楸(Liriodendronchinense(Hemsl.)Sarg.)的花被片一般为9枚,对贵州松桃(G)、湖南龙山(H)和浙江龙王山(Z)三地自然居群3年的观察发现,少数单株出现花被片数目变异,有10、11、12枚花被片情况。与居群G和H相比较,居群Z在单花花粉量,花粉大小和雌蕊数目等方面的变异较小,且无花被片数目变异。结实率与花部数目变异明显相关,变异较大的居群其结实率也高。居群间花粉平均大小与结实率有较好的正相关(r=076),并在居群间比较了结实率与花粉胚珠比(P/O)的关系(r=-074),发现P/O低的居群趋向于有较高的结实率,暗示资源配量限制了鹅掌楸的结实率。花部数量变异与结实率的关系表明潜在的遗传多样性对种子产量有明显影响。  相似文献   
84.
中国鹅掌楸小孢子发生的细胞化学研究   总被引:5,自引:0,他引:5  
多糖、脂类和蛋白质的消长变化与花粉发育过程中营养供应存在着密切的关系。雄蕊特别是花药壁内的多糖在减数分裂过程中逐渐消耗殆尽。初期的小孢子母细胞内脂滴的含量丰富,无淀粉粒,也无颗粒状的蛋白质。进行减数分裂的小孢子母细胞内、中层及绒毡层细胞积累了大量的蛋白质与脂类;减数分裂完成后,绒毡层和四分体小孢子开始逐渐积累淀粉与脂类,但蛋白质的含量较少,至小孢子时期,小孢子壁及绒毡层细胞的径切向壁和内切向壁沉积了大量的脂类物质,而且小孢子核周围分布大量淀粉粒,未观察到蛋白质颗粒。  相似文献   
85.
中国鹅掌楸天然群体与人工群体的生育力   总被引:19,自引:2,他引:17  
中国鹅掌楸(Liriodendronchinense(Hemsl.)sarg.)5个地点的群体与个体的生育力3年(1991~1993)研究结果表明:饱满翅果率为0.45~12.77%,饱满种子率为0.45~14.76%。不同群体间生育率有显著差异,同一群体不同年份间可塑性极大,在一个群体中个体间、聚合果间以及聚合果内不同部位间饱满翅果数的方差份量分别是49.46%、32.96%和17.58%;种于数的方差份量分别为44.52%、34.40%和21.08%。饱满翅果数与总翅果数之间不存在负相关,说明生育力不受资源限制,生育力低的原因可能是花粉限制,通过交配系统的进化与选择以及环境压力而起作用,结果限制了其生殖成功。  相似文献   
86.
The standing death rate of main communities in Aneurolepidium chinense (Trin.) Kitag. grassland increased slowly in 5–8 months. After August, the standing death rate greatly quickened because the changes of ecological environment limited the growth of plants. The maximum standing death rate of A. chinense and Calamagrostis epigejos(L.) Roth-weed communities was in October and that of Puccinella tenuiflora (Griseb). Scrihn. et Merr. and Suaeda glauca (Bunge) Bunge communities was in September. The seasonal changes of litter weight followed the index law. The communities in the order of litter weight were: C. epigejos-weed community. A. chinense community>P. tenuiflora community>S. glauca community. There was a positive relationship between aboveground standing crop and litter before August, and a negative relationship after August.  相似文献   
87.
Aneurolepidium chinense (Trin.) Kitag. is a perennial rhizome grass with fertile vegetative propagation. According to the field-investigation at fixed locations in fixed period, the seasonal change of vegetative propagation of A. chinense population and the autopopulation were specifically analysed. The results showed that both A. chinense population and the autopopulation could continuously make vegetative propagation in the entire growh season. The vegetative propagation brought more potential into play in the autopopulation of planting tillering than in the autopopulation of planting seedling, and the dynamics conformed to the Logistic curve growth for every experimental autopopulation in the planting growth season. The vegetative propagation of the population and the autopopulation was more seriously affected by the sexual development and the growth. The plant size was rigorously restricted by the population density, and the change of regularity followed–0.6699 power between mean weight per plant and the population density in the period of maximum biomass in the natural cutting grassland. The comprehensive analysis showed that A. chinense population depended on vegetative propagation and the population regeneration of the self-regulation, but the population hadnt far reached the most density which could be accommodated by standing conditions in the natural cutting grassland in the Songnen Plain of China.  相似文献   
88.
本文探讨了东北羊草草地割草场的钙、镁含量特征。研究结果表明:羊草群落中,植物根的钙、镁含量最高,季节变化规律是在生长旺季较高。羊草地上部分钙、镁积累量的季节变化曲线基本为S型,寸草苔和针蔺为双峰型。群落地下部分钙、镁积累量分别占群落总积累量的97.13%和92.08%。群落中钙、镁积累量仅占根层土壤钙、镁贮量的0.05%和0.03%,占根层土壤交换性和水溶性钙、镁贮量之和的52.2%和14.62%。植物各器宫中钙含量和积累量均大于镁。  相似文献   
89.
According to the yield of Aneurolepidium chinense (Trin.) Keng community and climatic variations from 1978 to 1990, the relationship between the yield and climatic factors was probed by correlation analysis. The results showed that the correlation degrees of Σ7—8 months' precipitation, Σ6--8 months' precipitation/Σ6--8 months' temperature and Σ4—7 months' sunshine in relation to the yield were 0.47, O. 41 and 0. 35 respectively and the correlation was in the order of 0.47>0. 41>0. 35. Water was the main limiting factor affecting the community yield. The effect of interation of water and heat factors on the yield was also extremely remakable. The yield of A. chinense community was simulated by using multiple regression equations and periodic variance analysis, reaching a simulated rate over 90%.  相似文献   
90.
Eupatorium adenophorum leaves cause hepatotoxicity and cholestasis in rats. The hepatotoxicant has been characterized as 9-oxo-10,11-dehydroageraphorone (ODA), a cadinene sesquiterpene. Oral administration of ODA, mixed in feed to rats, caused jaundice in 24 h. The liver of the intoxicated animals had focal areas of hepatocellular necrosis, proliferation, and dilation of bile ducts with degenerative changes in the lining epithelium. There was marked increase in the conjugated form of plasma bilirubin and in the activities of the enzymes glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, alkaline phosphatase, lactate dehydrogenase, gamma-glutamyltranspeptidase, glutamate dehydrogenase, and 5'-nucleotidase. The histopathological lesions in liver and biochemical profile of marker enzymes show that ODA induced hepatotoxicity and cholestasis in rats. This is the first report on the toxicity of a cadinene sesquiterpene in rats.  相似文献   
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