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1.
Anthers of Vitis latifolia L. (wild grape) cultured on Nitsch and Nitsch medium supplemented with 20 μM 2,4-D and 9 μM BAP produced callus after 4–6 weeks. Subculture of callus onto Nitsch and Nitsch medium containing 10 μM NAA produced somatic embryos within 6 weeks. On growth regulator-free Nitsch and Nitsch basal medium somatic embryos converted to plantlets in 6–8 weeks. One gram of callus produced more than 400 somatic embryos with 13.7% being converted to complete plantlets, which were subsequently established in soil. Regenerated plants were found to have mixoploid populations of cells, 2n = 38 and n = 19. Received: 23 May 1998 / Revision received: 21 September 1998 / Accepted: 10 October 1998  相似文献   
2.
Typha latifolia L. from aquatic plants is widely found throughout Kehli Stream (Elazig, Turkey). This study examined the uptake of some metals by T. latifolia and the transfer from roots to other plant parts. The accumulation of Mn in T. latifolia L. can be suggested as a tolerance strategy due to its transfer factor higher than 1.0. The enrichment coefficients in the leaves of T. latifolia L. were higher than 1.0 for Zn and Mn and often lower than 1.0 for other metals. Similarly, the enrichment coefficients of all metals, except for Cr, in roots of T. latifolia L. were higher than 1.0. This study demonstrated that T. latifolia L. could be considered as either a bio-indicator or a bio-accumulator for sediments and water polluted by metals.  相似文献   
3.
Among the variety of breeding systems developed by flowering plants, those based on heteromorphic sex chromosomes are the most intellectually challenging in evolutionary terms. This is because, among other things, they enable us to compare sex determination processes between plants and animals. White campion (Silene latifolia, also named Lychnis or Melandrium) is dioecious and, much like us, females are homogametic (XX) and males are heterogametic (XY). Sexual dimorphism in white campion is controlled by two independent developmental pathways operating from the Y chromosome at very early developmental stages and within distinct regions of the flower. In addition, all basic steps in the evolution from the bisexual to the dioecious condition with heteromorphic sex chromosomes are known and available to experimentation in the genus Silene. This group of species has been under scrutiny for more than a century. Such an ideal experimental system enables us to tackle, with novel methodological tools, several classical questions in biology. These include the question of how sexual dimorphism evolved and how dimorphic development is controlled, as well as questions of how sex chromosomes evolve in the absence of meiotic recombination or how male-female genetic conflicts are generated. At the turn of the century, the time is now ripe to have a closer look. Received: 21 September 1999 / Accepted: 11 October 1999  相似文献   
4.
Senescent, naturally dried leaves of Typha domingensis were incubated inthe littoral region of a coastal lagoon and epiphytic bacterial volume,abundance, biomass and secondary productivity were measured during 127 daysof decomposition. The peak of cell abundance was registered at t =127 days when expressed per leaf surface area (10.07×107cells cm-2; 7.26 µgC cm-2), and at t= 26 days when expressed per biofilm dry mass (38.10 ×107 cells (mgDM biofilm)-1, 30.52 µgC(mgDM biofilm)-1). The highest values of bacterial biovolumesand lower turnover time were usually obtained in the beginning of thecolonization. Leu:Tdr ratios were also higher in the beginning of thecolonization, when bacterial community presented unbalanced metabolism.Consequently, the highest discrepancies between the bacterial secondaryproduction estimated by leu and Tdr incorporation were observed in the first2 days of decomposition. On average, the bacterial secondary productivityestimated by leu incorporation was 2.1 times higher than the valuesestimated by Tdr incorporation when the empirical factor for Tdr wasobtained from the relationship between Tdr and biomass increment. Thisdifference increased to 4.2 when the empirical factor was obtained from therelationship between Tdr and cell numbers increment. An average of bothmethods (0.0037 to 0.1397 µgC cm-2 h-1)produced results that fall within the range reported in the literature forepiphytic bacteria of freshwater ecosystems.  相似文献   
5.
A novel compound (1) and a known one (2) were isolated from Makomotake, Zizania latifolia infected with Ustilago esculenta, as osteoclast-forming suppressive substances.  相似文献   
6.
宽叶大戟化学成分的研究   总被引:9,自引:3,他引:6  
对宽叶大戟(Euphorbia latifolia)的化学成分进行研究。从其乙醇提取物的石油醚、乙酸乙酯部位分离得到10个化合物,经理化常数和波谱分析,分别鉴定为:山萘酚(kaempferol,1)、槲皮素(quercetin,2)、山萘酚-3-O-β-D-葡萄吡喃糖苷(kaempferol-3-O--βD-glucopyranoside,3)、槲皮素-3-O--βD-葡萄吡喃糖苷(quercetin-3-O--βD-glucopy-ranoside,4)、白桦酯酸(betulinic acid,5)、白桦酯醇(betulin,6)、齐墩果酸(oleanolic acid,7)、胡萝卜苷(daucosterol,8)、β-谷甾醇(-βsitosterol,9)、正二十八烷醇(1-octacosanol,10)。化合物1~10均是首次从该植物中获得。  相似文献   
7.
Studies were conducted on the influence of Kitazin analogues on the incorporation of 14C-glucosamine into the mycelial cell wall fraction of Pyricularia oryzae. Compounds of thiolates and phosphates, both having in vitro inhibitory activities toward the mycelial growth, inhibited the incorporation, whereas those of thionates and dithioates, either having no fungitoxicity, did not inhibit the incorporation. Mycelia of P. oryzae treated with Kitazin-P (S-benzyl O,O′-diisopropyl phosphrothioate; IBP) accumulated about twice as much an amino sugar derivative as untreated ones. Mycelia treated with thiono or dithio analogues, which have no fungitoxicity, showed no accumulation. The accumulated substance gave a identical spot with authentic UDP-N-acetyl glucosamine on paper chromatograms developed with four solvent systems.  相似文献   
8.
通过腊叶标本研究、野外观察和文献考证,结合栽培试验,研究了香蒲科水烛(Typha angustifolia L.)花部结构特征,补充描述了该种丝状毛在子房柄上的着生方式、小穗不孕雌花数目等性状特征,观察了在成熟期不同阶段其孕性雌花柱头与小苞片的长度变异。结果显示,水烛孕性雌花小苞片呈宽披针形、匙形或条形,先端褐色,短于柱头,或与柱头近等长或稍长于柱头;子房柄上的丝状毛除少数散生外,多数基部合生呈鞘状或束状,在子房柄下部呈1~4轮排列;小穗不孕雌花常3(~4)枚。研究材料在7月中旬前后雌花小苞片明显短于柱头,随果穗成熟小苞片与柱头近等长。长苞香蒲(T.domingensis Pers.)子房柄上的丝状毛形态和着生方式与水烛中的情况基本一致,但小苞片白色透明,小穗不孕雌花常1(~2)枚。这表明水烛孕性雌花小苞片和柱头的长度比例与不同成熟阶段有关系,不宜作为与长苞香蒲的区别特征,而小穗不孕雌花数目和小苞片颜色等特征对两物种的划分有较重要的意义。  相似文献   
9.
建立HPLC同时测定大叶冬青叶中新绿原酸、绿原酸、隐绿原酸、咖啡酸、对羟基肉桂酸、芦丁、异槲皮苷、异绿原酸B、异绿原酸A和异绿原酸C 10种多酚类化合物的定量分析方法,研究不同产地及不同采收时期大叶冬青叶中10种多酚类化合物的含量差异及其抗氧化活性。采用HPLC测定大叶冬青叶50%甲醇提取液中10种多酚类成分的含量,并选用DPPH法对其抗氧化活性进行初步探索。结果表明,10种多酚类化合物分离效果较好,标准曲线在检测范围内具有良好的线性(r>0.999 5),平均加样回收率在96.58%~112.03%,RSD<4%(n=6)。大叶冬青叶50%甲醇提取液抗氧活性良好。本实验建立的方法快速、准确、重复性好,可用于同时测定大叶冬青叶中新绿原酸、绿原酸、隐绿原酸、咖啡酸、对羟基肉桂酸、芦丁、异槲皮苷、异绿原酸B、异绿原酸A、异绿原酸C 10种成分的含量;不同产地、不同采收时期大叶冬青叶中10种多酚类化合物含量存在一定差异;不同来源大叶冬青叶50%甲醇提取液抗氧化能力具有明显差异。  相似文献   
10.
Abstract

Landfilling has been widely used for solid waste disposal; however, the generation of leachate can pose a major threat to the surrounding environment in the form of soil salinity. Two native plants of North America Puccinellia nuttalliana (alkaligrass) and Typha latifolia (cattail) were selected in this study to investigate bioaccumulation of sodium (Na+) and chloride (Cl?) under controlled greenhouse conditions. The treatments include irrigation of the plants using fertilizer (F), landfill leachate (LL), and tap water (control, C). Plants cultivated after one season (12?weeks) were harvested by separating aboveground tissues and roots, and soil from each treatment was collected for analysis. The results show that alkaligrass irrigated with LL had 2.13% more biomass yield than control, but 17.63% less than that with F. However, cattail yielded 19.70% more biomass with the irrigation of LL than C and 3.04% less compared to F. Alkaligrass and cattail accumulated 6.85 and 7.00?g Na+/Kg biomass with the irrigation of LL, respectively. Alkaligrass and cattail irrigated with LL accumulated 120.14% and 94.47% more Cl? than C. When alkaligrass and cattail were irrigated with LL, the electrical conductivity of soil was reduced by 71.70% and 45.36%, respectively. This study demonstrated that using North American native halophytes could be a cost-effective and promising approach for phytoremediation of landfill leachate.  相似文献   
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