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71.
从贵州鼠尾草95%乙醇提取物分离得到8个化合物,通过理化性质及波谱方法分别鉴定为正三十三烷(1),十二烷酸十四烷酯(2),β-谷甾醇(3),胡萝卜苷(4),乌苏酸(5),2 a,3β-二羟基乌苏酸(6),白桦酸(7)和迷迭香酸(8)。以上化合物均首次从该植物中分离得到。  相似文献   
72.
丹参雄性不育系Sh-B的鉴定与花粉发育过程的解剖学研究   总被引:1,自引:0,他引:1  
在显微水平上对新发现的丹参雄性不育系Sh-B花药发育过程进行了解剖学观察,并对其花粉活力和结实率进行了鉴定。结果显示:根据花器官及花药的形态、大小以及花丝的长度,可以将Sh-B不育株分为3个不育类型,即Sh-B1、Sh-B2和Sh-B3。这3种不育类型均属于雄性不育,其花丝不到正常可育株的1/2,花药干瘪而瘦小,内无花粉粒或花粉无活力;其根、茎、叶以及种子形态结构与正常可育植株基本相似。产生雄性不育的主要原因有:花粉囊药室内壁纤维层加厚,影响花药壁开裂;小孢子母细胞周围不产生胼胝质或产生的胼胝质很少;绒毡层细胞延迟解体;花粉粒畸形。在其花药发育的小孢子母细胞时期、四分体形成前期、单核期、双核期均可能产生雄性不育的小孢子或花粉粒。  相似文献   
73.
对丹参EST序列进行Blast分析,获得一个新的非特异性脂质转移蛋白基因,命名为SmLTP1(GenBank注册号为EF187461)。该基因cDNA全长593bp,包含一个长为357bp的开放读码框,编码118个氨基酸。生物信息学结构分析表明,该蛋白具有植物nsLTP的典型结构,即4对二硫键,4个a-螺旋,1个可结合和容纳脂肪酸分子的类似口袋状的疏水结构。实时荧光定量PCR分析结果表明,SmLTP1基因在丹参不同组织器官中差异表达,其表达受病原菌和茉莉酸甲酯的诱导,显示SmLTP1基因在植物防御反应中发挥作用。  相似文献   
74.
Ne'eman  Gidi  Dafni  Amots  Potss  Simon G. 《Plant Ecology》2000,146(1):97-104
The recovery of vegetation following fire has been studied intensively in Mediterranean-type ecosystems. Little attention, however, has been given to floral traits, and almost no data have been collected on the effects of fire on pollinator activity and fruit-set. This paper reports the effects of fire on flower visitation rates and the possibly related fruit-set. We compared visitation rates of the main pollinators on four plant core-species in burned and adjacent unburned areas. Measurements were performed at an unburned phrygana (scrub lands), and at a burned area (5–7 years post-fire). Bumble bees and solitary bees were the main taxa of visitors, while few honeybees were recorded. Solitary bees were almost absent from the burned area. Fruit-set was significantly higher in the unburned area for three out of the four plant species. The lower fruit-set in the burned area was possibly the result of low activity of solitary bees which are the main effective pollinators of the examined species. We hypothesize that the populations of the solitary bees were diminished or extirpated either directly by the fire, or indirectly by the scarcity of nectar in the early post-fire years due to dominance of young pine and Cistus spp. seedlings. The short foraging range of the solitary bees and their slow invasion rate into the burned area may explain our results.  相似文献   
75.
The aim of this study was to investigate the essential oil profile of Salvia thomasii (Southern Italy) and to assess the relationship of this taxonomic unit to S. fruticosa. The essential oil, obtained by hydrodistillation, was analysed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The main components are β-pinene, viridiflorol, 1,8-cineole, camphor, α-pinene and trans-caryophyllene. The oil was tested for its potential antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Ability Power (FRAP) and β-carotene bleaching test. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity assays were used to screen the neuroprotective effect of the essential oil. A clear distinction of the two taxonomic units emerge by the comparison of S. thomasii and S. fruticosa s.l. essential oil composition. Considering the weak morphological differences and the clear-cut geographic separation we propose to treat the Italian unit at subspecies level as Salvia fruticosa Mill subsp. thomasii (Lacaita) Brullo, Guglielmo, Pavone & Terrasi.  相似文献   
76.
Abstract.  1. Host plant finding in walking herbivorous beetles is still poorly understood. Analysis of small-scale movement patterns under semi-natural conditions can be a useful tool to detect behavioural responses towards host plant cues.
2. In this study, the small-scale movement behaviour of the monophagous leaf beetle Cassida canaliculata Laich. (Coleoptera: Chrysomelidae) was studied in a semi-natural arena ( r = 1 m). In three different settings, a host ( Salvia pratensis L., Lamiales: Lamiaceae), a non-host ( Rumex conglomeratus Murr., Caryophyllales: Polygonaceae), or no plant was presented in the centre of the arena.
3. The beetles showed no differences in the absolute movement variables, straightness and mean walking speed, between the three settings. However, the relative movement variables, mean distance to the centre and mean angular deviation from walking straight to the centre, were significantly smaller when a host plant was offered. Likewise, the angular deviation from walking straight to the centre tended to decline with decreasing distance from the centre. Finally, significantly more beetles were found on the host than on the non-host at the end of all the trials.
4. It is concluded that C. canaliculata is able to recognise its host plant from a distance. Whether olfactory or visual cues (or a combination of both) are used to find the host plant remains to be elucidated by further studies.  相似文献   
77.
Bioguided-fractionation of an acetone extract of the roots of Salvia cilicica (Lamiaceae) led to isolation of two new diterpenes, 7-hydroxy-12-methoxy-20-nor-abieta-1,5(10),7,9,12-pentaen-6,14-dione and abieta-8,12-dien-11,14-dione (12-deoxy-royleanone), together with oleanolic acid, ursolic acid, ferruginol, inuroyoleanol and cryptanol. Their structures were determined spectroscopically, which included HREIMS and 2D NMR spectroscopic analysis. The new abietane derivatives showed appreciable in vitro antileishmanial activity against intracellular amastigote forms of both Leishmania donovani (IC(50) values of 170 and 120 nM, respectively) and Leishmania major (IC(50) values of 290 and 180 nM, respectively). The triterpenoic acids were found to be potently active against amastigote (IC(50) values of 7-120 nM) and moderately active against promastigote stages (IC(50) values of 51-137 nM) of the two Leishmania species.  相似文献   
78.
79.
迷迭香酸(RA)是丹参中一种重要的酚酸类次生代谢物。为探讨水杨酸(SA)诱导子对丹参悬浮培养细胞中RA的生物合成及其相关酶的影响,考察了SA诱导子和酪氨酸氨基转移酶(TAT)的竞争性抑制剂(AOPP)对RA合成积累量、苯丙氨酸解氨酶(PAL)和TAT活性的影响。发现在培养的第6天用浓度为6.25 mg/L的SA处理后,PAL活性在诱导后4 h出现高峰,为对照组水平的124%;RA的积累量在诱导后8 h出现峰值(5.914±0.296)mg/g。用浓度为0.1μmol/L的AOPP处理,6 h后AOPP对TAT活性影响较小(与对照组无显著差异),但明显抑制了PAL活性(为对照组水平的44%),且在PAL活性明显降低的同时RA的积累量显著减少(4.709±0.204)mg/g。进一步用0.1μmol/L AOPP和6.25 mg/L SA共处理,AOPP对PAL的抑制作用可得到一定程度的缓解,且RA的积累量较AOPP单独处理的高。表明SA可以诱导丹参悬浮培养细胞中RA积累量的增加,且在RA合成过程中PAL的限速作用比TAT明显。  相似文献   
80.
药用鼠尾草属数值分类与丹参药材道地性   总被引:24,自引:0,他引:24  
运用数值分类方法,将鼠尾草属(SalviaL.)药用植物资源划分为3类:高山丹参类、低山丹参类和非丹参类。该结果为鼠尾草属植物分类鉴定、资源开发及丹参药材道地性研究提供了新的参考依据  相似文献   
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