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1.
天然线性二芳基庚烷类化合物   总被引:15,自引:0,他引:15  
本文对目前已发现的天然线性二芳基庚烷类化合物在植物中的分布及其结构特征,生源合成途径和药理学研究进展作一简要的综述。  相似文献
2.
姜科植物地理   总被引:9,自引:1,他引:8       下载免费PDF全文
本文讨论了姜科的分类系统、起源、进化和地理分布.姜科为一还热带分布科,按Burtt[8]的系统分2亚科4族.全世界有52属,约1377种,其中姜亚科含48属,1268种.主要分布于热带亚洲.其现代分布中心在印度-马来西亚。闭鞘姜亚科含4属,109种,主要分布于热带美洲及非洲。本文在化石资料及现代分布资料的基础上,讨论了姜科的早期分化时间、地点及现代分布格局形成。化石记录表明.欧洲、北美及印度的白垩纪、早第三纪均发现过姜科的化石,据此姜科植物的起源时间应不晚于早白垩纪。姜亚科的早期分化中心推论在劳亚古陆的南部.欧洲和北美没有现代姜科的分布是因为第三纪冰期的影响.而亚洲热带地区现代姜科植物繁盛是因为气候适宜.且相对稳定所致.南美的姜亚科种类应是由非洲传人.而大洋洲的姜亚科种类则是由马来西亚传入.闭鞘姜亚科的早期分化中心推论在西冈瓦纳古陆.亚洲及大洋洲的闭鞘姜亚科的种类应是随印度板块飘向亚洲时传入。中国姜科植物有22属.209种(占全世界属的42%.种的15%).主要分布于马来西亚亚区(占全国属的90%).其次为中国喜马拉雅亚区(占全国属的68%)。最少为中国-日本亚区(占全国属的45%)。统计数字表明.马来西亚#0;  相似文献
3.
Pollen histochemistry and pollen : ovule ratios in Zingiberaceae   总被引:7,自引:0,他引:7  
BACKGROUND AND AIMS: Pollen grains of 37 species from 11 genera in the family Zingiberaceae were examined to assess qualitatively starch or lipid contents; the pollen grain and ovule numbers per flower and pollen : ovule ratios were also counted and calculated. Pollen : ovule ratios were studied to reveal patterns of variation in the Zingiberaceae. METHODS: Freshly open flowers with dehiscing anthers were collected at random from plants growing in natural habitats or in botanical gardens. Presence of lipids or starch in pollen grains was tested by Sudan solution and IKI solution, respectively, and examined under a microscope. To estimate the pollen and ovule numbers per flower, one anther from each bud was carefully dissected and all pollen grains were counted; ovaries were carefully dissected out of each flower and counted. Whenever possible, at least 10-15 buds were used in the determination. KEY RESULTS: Thirty-three of all the 37 species examined had starchy pollen. Starch was not found in only four species and lipid was not found in only one species; among the four tribes in subfamily Zingiberoideae, all species of Zingibereae and Globbeae had pollen with no starch, Alpineae and Hedychieae had pollen with and without starch, whereas, all species of subfamily Costoideae had starchy pollen with abundant lipids. The mean pollen : ovule ratios in the members of the Zingiberaceae investigated range from 3.25 +/- 1.56 to 616.52 +/- 117.83. CONCLUSIONS: The pollen nutrition types seemed not related to mating systems. The pollen : ovule ratios in members of the Zingiberaceae with the same breeding system are noticeably lower than those recorded by previous authors. The lower pollen : ovule ratios in this family are presumed to be related to the highly efficient pollination systems, mediated by pollen which can be quite glutinous and the relatively large stigma area. In most of the Alpinia species the anaflexistylous flowers have much larger numbers of pollen grains and higher pollen : ovule ratios than the cataflexistylous flowers. There are significant differences in mean pollen grain numbers and pollen : ovule ratios between different life forms but ovule numbers are approximately the same.  相似文献
4.
中国姜黄属植物的订正   总被引:7,自引:0,他引:7       下载免费PDF全文
将白顶姜黄(CurcumaalbicomaS.Q.Tong)归入川郁金(C.sichuanenslsX.X.Chen),将另一种“川郁金”(C.chuanyujinC.K.HsiehetH.Zhang)归入广西莪术(C.kwangsiensisS.G.LeeetC.F.Liang)。认为过去把莪术鉴定为C.zedoaria(Christ.)Rose.C.caesiaRoxb.或C.aeruginosaRoxb,其实都是C.phaeocaulisVal.的误定;C.elataRoxb.是C.wenyujinY.H.ChenetC.Ling的误定;认为广西莪术的两个变种,即紫脉莪术(C.kwangsiensisvar.affinisY.H.Chen)和毛莪术(C.kwangsiensisvar.puberulaY.H.Chen)不能成立.对台湾是否产C.viridifloraRoxb.表示怀疑。附有中国产姜黄属植物12种的检索表及其分布.  相似文献
5.
6.
姜科植物的引种   总被引:5,自引:0,他引:5       下载免费PDF全文
华南植物园二十多年来共引种姜科植物23属,135种,3变种,3变型,其中存活18属,103种,2变种,2变型。对长果姜(Siliquamomum tonkinense Baill.)、茴香砂仁「Etlingera yunnanensis(T.L.Wu et Senjen)R.M.Smith」等三级保护植物进行了迁地保护。姜科植物在我园引种有高的成活率,开花结实的种类较多,引种较为成功,特别是原产亚  相似文献
7.
Micropropagation and field evaluation of micropropagated plants of turmeric   总被引:3,自引:0,他引:3  
A protocol was developed for in vitro propagation of turmeric cv `elite' using young vegetative buds from sprouting rhizomes. The shoot buds produced multiple shoots when cultured on MS solid medium supplemented with benzyladenine and 1-naphthalene acetic acid. The effect of various cytokinins on shoot multiplication was studied by culturing the shoot tips on MS liquid medium supplemented with benzyladenine, benzyladenine riboside, kinetin, kinetin riboside, zeatin, 6-,-dimethylallylaminopurine, adenine, adenine sulfate or metatopolin each at 10 M in combination with 1-naphthalene acetic acid (1 M). Significant differences were observed between the treatments. Liquid medium was more favourable than agar medium for shoot multiplication. Among the various concentrations of agar tested, 0.4% and 0.6% were the best and produced the highest number of shoots per explant. Among the different carbohydrates tested, sucrose, fructose, glucose, sugar cubes, maltose, levulose and market sugar were found to be equally effective for shoot multiplication and xylose, rhamnose, lactose and soluble starch were inhibitory. Ninety five percent of the micropropagated plants survived in sterilized soil in paper cups and all of them survived in the field. Among 48 plants, two plants showed variegated leaves on the tillers. The micropropagated plants showed a significant increase in shoot length, number of tillers, number and length of leaves, number of fingers and total fresh rhizome weight per plant when compared with conventionally propagated plants. RAPD analysis of 11 regenerated plants using sixteen 10-mer primers did not show any polymorphism.  相似文献
8.
国产姜科植物的染色体计数(5)   总被引:3,自引:0,他引:3  
<正> 本文继续对7属15种国产姜科植物作染色体计数观察,其中10种是染色体计数的新纪录(表、图)。通过对黄花大苞姜(Caulokaempferia coenobialis)和大苞姜(C.yunnanensis)以及凹唇姜(Bosenbevgia rotunda)和心叶凹唇姜(B.fallax)的染色体观察,确定了大苞姜属(Caulokaempferia)和凹唇姜属(Bosenbergia)的染色体基数分别为12和9。  相似文献
9.
广西单子叶植物五新种   总被引:3,自引:0,他引:3  
广西单子叶植物五新种方鼎,覃德海(广西中医药研究所,南宁530022)关键词仙茅科,球序仙茅,兰花蕉科,长萼兰花蕉,姜科,裂舌姜,少斑姜,长腺姜FIVENEWSPECIESOFMONOCOTYLEDONEAEFROMGUANGXI¥FangDing;...  相似文献
10.
毛姜花原变种花寿命对两性适合度的影响   总被引:3,自引:1,他引:2       下载免费PDF全文
  植物的花寿命被认为是由雌、雄适合度的增长和维持花开放的花费之间的平衡来决定的。姜花属(Hedychium)是姜科唯一一个从热带到高海拔地区分布的大属, 属内不同种类植物的花寿命差异很大。毛姜花原变种(H. villosum var. villosum)的花寿命为5 d, 显著长于其它同域分布的姜科植物。通过人工剪除毛姜花原变种的柱头来使花朵具雌性功能的时间缩短, 结果显示: 在不同的处理中, 结实率随花朵具雌性功能时间的延长而增加, 开花1 d后剪除柱头的结实率为1.85% ± 1.59%, 极显著低于对照的结实率20.96% ± 4.13%, 说明其较长的花寿命能显著地增加传粉的成功率和结实率, 长达5 d的花寿命有利于雌性适合度的提高。同时, 毛姜花原变种开花1 d后, 剩余的平均花粉数和总平均花粉数没有显著差异, 而开花后2、3和4 d后剩余的平均花粉数则极显著少于总平均花粉数, 说明随着花寿命的延长, 花粉输出量也显著增加, 其长达5 d的花寿命也有利于其雄性适合度的提高。较长的花寿命在毛姜花原变种拓展新的生境、向更高海拔地区的扩散中也许起着重要的作用。姜科植物有着极其多样性的传粉和繁育系统, 花寿命在姜科植物传粉和繁育系统的多样性形成及其进化中起着重要作用, 同时, 较长的花寿命有效地提高了雌性适合度和雄性适合度, 从而使姜科植物能脱离热带生境, 向更高海拔的地区扩散, 花寿命在姜科植物从热带地区到高海拔地区的分布过程中也起着重要作用。  相似文献
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