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91.
The inner structure of the ovary inImpatiens was examined from the viewpoint of taxonomy, based on the materials obtained during the 1979 Botanical Expedition to Thailand.
The species studied areI. kerriae, I. larsenii, I. hongsonensis, I. psittacina, I. salaengensis, I. charanii, I. kanburiensis andI. macrosepala. It is worthy of special mention that they are all characterized by 4 lateral sepals, large round outer sepals, a nipple-like
short spur of the lip and connate wing petals. Contrary to the prevailing information about the ovary ofImpatiens, these Thai species were found to have 4-locular and 4-carpellate ovaries. The arrangement and the number of ovules in a
loculus show a tendency of reduction from biseriate to uniseriate and from several to single or none. The species of more
advanced type have smaller numbers of ovules and often sterile loculi of the ovary, as represented byI. macrosepala. The types of ovule development were proved to correspond to the degree of specialization of floral characters.
Supported by a Grant in Aid of Scientific Research of Ministry of Education, No. 404126 and No. 504352, and partly reported
at the Meeting of the Japan Society of Plant Taxonomists in March 1981. 相似文献
92.
The effect of oil spills on the recruitment of freshwater tidal wetland species was determined using soil seed bank samples collected in early March from two New Jersey Delaware River marshes. Samples were exposed to simulated tidal cycles 0 (2 days), 2 and 4 wk after soil was collected; 0 wk samples were treated before germination began. Oil treatment significantly reduced survival to I May (end of study) of Acnida cannabina and Bidens laevis, the dominant species, as well as number of species per sample and height of B. laevis. Total perennial seedlings, present in low numbers, also showed significant reduction with treatment. However, during the course of the study, Peltandra virginica recruitment and survival were not reduced by oil treatment and recruitment of Sagittaria latifolia appeared enhanced. There was no consistent pattern regarding which treatment time produced the greatest effect. Interactions (site, treatment, time) were generally not significant. Because these tidal freshwater wetlands and seed banks are dominated by annuals, reduction in seedling numbers and growth could substantially alter vegetation patterns. Timing of oil spills would be important, but impact would depend on species composition of the seed bank and colonizing vegetation, dispersal of seeds into the site, and germination requirements. 相似文献
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凤仙花属(Impatiens)植物主要分布于旧世界的热带和亚热带山区, 对生长环境要求极度严苛, 深入分析其地理分布格局与特征, 可为种质资源调查和利用提供理论依据。本研究通过系统检索文献资料, 更新了该属植物物种名录, 整合其地理分布、海拔、特有性等信息, 建立了中国野生凤仙花属植物地理分布数据库。截至2022年3月, 中国共记载野生凤仙花属植物352种(包含18变种1亚种1变型), 其中中国特有种273种。除上海市外, 中国其他各省级行政区均有野生凤仙花属植物分布, 其中云南省分布有165种, 其次为四川省(119种)和西藏自治区(69种)。县级尺度上, 贡山独龙族怒族自治县和腾冲市以51种并列物种丰富度第一, 其次是福贡县(42种)。中国野生凤仙花属的分布总体呈现以热带、亚热带为中心向高纬度和高海拔区域扩散的格局, 广义横断山区、西藏南部地区、滇黔桂喀斯特区域、长江中下游等地为凤仙花属植物集中分布的热点地区。 相似文献
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凤仙花属两种植物花粉的扫描电镜制样研究 总被引:5,自引:0,他引:5
采用腊叶标本花粉直接制样法、烘干法、FAA固定液复原法(酒精梯度脱水、自然干燥)和FAA固定新鲜花药法(脱水、干燥处理同前)四种不同处理方法对凤仙花属(Impatiens L.)植物红纹凤仙花(I.rubro-striata Hook.f.)和长角凤仙花(I.longicornut Y.L.Chen)的花粉进行了制样研究。结果表明:经后两种方法处理的花粉形状不变,且外壁网纹清晰,可获得质量较高的照片,观察时间也不受季节和产地的影响,既可在野外固定保存新鲜花蕾备用,又可利用标本馆现有的腊叶标本花粉经固定液复原后制样观察,操作简便,是进行花粉形态研究的一种较理想的方法。 相似文献
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