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31.
南五味子属(五味子科)植物叶表皮形态特征   总被引:2,自引:0,他引:2  
在光学显微镜和扫描电镜下,观察了南五味子属(Kadsura Kaempf. ex. Juss.)全属11种,八角属(Illicium Linn.)2种,共108个样品的叶表皮特征。在南五味子属中,叶表皮细胞的形状、叶表皮表面的纹饰、气孔器的形状、气孔极区的形状、表皮毛的有无等性状能用于研究南五味子属种间关系,以及与五味子属(Schisandra Michaux)和八角属之间的关系。在八角目(Illiciales)中发现的一个新分类学性状(叶表皮表面具角质网纹),支持将南五味子属分为离蕊南五味子亚属(Subg. Cosbaea)和南五味子亚属(Subg. Kadsura)。根据叶表皮形态特征,支持将南五味子亚属分为南五味子组(Sect. Kadsura)和肉蕊组(Sect. Sarcocarpon),支持R. M. K. Saunders和林祁对某些种的归并处理。根据与五味子属和八角属叶表皮形态特征的比较,认为这3个属的叶表皮形态特征相似,但南五味子属叶表皮形态比五味子属和八角属的叶表皮形态复杂,不支持将五味子科(Schisandraceae)从八角目(Illiciales)中分出而成立五味子目(Schisandrales)的观点。  相似文献   
32.
A new dibenzocyclooctane lignan, schisanbicolorin A, together with fifteen known lignans, were isolated from the stems of Schisandra bicolor Cheng. Their structures were identified as (aS,6R,7S)-5,6,7,8-tetrahydro-2,3,13-trimethoxy-6,7-dimethyldibenzo[3,4]cycloocta [1,2-f][1,3]benzodioxol-1-ol (1), neglschisandrin C (2), angeloylgomisin R (3), schisantherin D (4), gomisin F (5), schisantherin B (6), tigloylgomisin Q (7), gomisin G (8), interiotherin B (9), schisandrin (10), angeloylgomisin H (11), benzoylgomisin H (12), gomisin H (13), angeloyl−(+)−gomisin K3 (14), deoxyschizandrin (15), and (+)-gomisin K3 (16), respectively, based on spectroscopic analysis and by comparison of their spectral data with those reported previously in the literature.  相似文献   
33.
This study analyses the pollination systems and biogeography of three allopatdc species of Schisandra (Section Euschisandra) consisting of S.glabra (North America),S.bicolor (China),and S.repanda (Japan); the clade is delimited in a phylogenetic tree of Schisandraceae constructed with nuclear and plastid genes.The male and female flowers of these species have similar floral structures,but exhibit different pollination systems.At the base of the clade,S.glabra is pollinated by a wide variety of beetles and flies in a generalist pollination system that also includes floral heat and the use of male and female flowers as brood sites for insects.In Asia,however,S.bicolor and S.repanda are pollinated exclusively by one or two different species of gall midges (Resseliella spp.) in a specialist pollination system.In this system only female,pollen-eating gall midges pollinate the flowers and breed on nearby spiderwebs.The gall midge pollination system is specialized and derived from the generalist system in S.glabra,and basal in the clade.Pollen is the main floral resource,and we hypothesize it is exploited to enrich eggs,and as a result species of gall midges could increase reproductive fitness by feeding on a single dependable food source.Subsequently the life cycles of the plants and insects evolved into a tight association in old stable plant communities in the Sino-Japanese flora.Divergence times for the plant species are presented and correlated with past distributions and migration routes.  相似文献   
34.
The fruits of Schisandra sphenanthera (dioecious) are used to produce ‘Nan-Wuweizi’, an important Chinese medicine. However, long-term exploitation and habitat destruction have threatened these plants in nature. Knowledge of the reproductive biology of S. sphenanthera is essential to help formulate a conservation strategy for these plants. Field studies were conducted at Jigong Mountain (JGM) and Jinji Valley (JJV) in Henan and Hubei Provinces, China. The reproductive biology of S. sphenanthera was analyzed at these sites, including population structure, pollination, floral morphology, and natural fruit set. The 11 populations at two sites were male biased. The primary floral visitors were gall midges (Resseliella sp., Cecidomyiidae; Diptera) and thrips (Thrips flavidulus; Thysanoptera). Floral visitor exclusion experiments and pollen load analysis indicate that gall midges are the primary pollinators. Pollen was the only floral reward for the gall midges. Female flowers attracted pollinators using deceit. The natural fruit set ratio in the cut forest site (JJV) was significantly lower than that at the JGM site, where habitats of S. sphenanthera were well preserved. This indicates that the life cycles of S. sphenanthera and the pollinating insects are vulnerable in disturbed (or cut) habitats.  相似文献   
35.
首次报道用扫描电镜观察的五味子科24种7变种1变型的92个居群117份种子样品的表面微形态特征。将该科种子表面微形态归纳为4大类型,其中第Ⅰ型又分为3个亚型。将种子表面微形态与该科的花粉微形态,以及花、果、茎和叶的宏观形态结合起来进行对比分析,结果表明,五味子科种子表面微形态特征几乎不受其植株生长地环境条件的影响,相当稳定,因而作为分类的鉴别特征完全可靠。已观察到的种子表面微形态特征不支持林祁和Saunders对五味子科所做的大部分分类学修订结果。种子表面微形态特征所揭示的Schisandra属与Kadsura属之间的关系,与花粉形态所揭示的两属关系极其相似,即两属可能起源于共同的祖先,分别沿两条不同路线演化,但亦不能排除两属间有更复杂的关系的可能性。Kadsura属的总体演化水平高于Schisandra属,因而不支持认为Kadsura属比Schisandra属原始的观点。  相似文献   
36.
37.
The two-dimensional data obtained from GC-MS has been used qualitatively and quantitatively to determine the components of the volatile fractions of Schisandra chinensis obtained by six different extraction methods. Sub-window factor analysis (SFA) was employed to confirm the identities of components determined in different samples. With the help of SFA, and other chemometric techniques, peak purity in the chromatograms was determined, and overlapping peaks were resolved to yield a pure chromatographic profile and mass spectrum for each component. It is demonstrated that the accuracy of qualitative and quantitative analysis may be greatly enhanced using chemometric resolution methods, such methods being particularly valuable with respect to the analysis of complex samples such as traditional Chinese medicines. It is further demonstrated that different extraction methods give rise to volatile fractions of S. chinensis which differ qualitatively and quantitatively in their composition.  相似文献   
38.
目的:研究炮制对北五味子水浸率的影响,考察水浸率作为评价五味子质量优劣的辅助参考质量指标的可行性。方法:观察炮制时间、炮制温度、炮制辅料用量改变对五味子水浸率的影响。结果:炮制时间、炮制温度及炮制辅料用量对五味子水浸率都有一定影响。从炮制对五味子水浸率影响结果来看:蜜制五味子以炮制4-6小时、蜂蜜加入量为60-80g五味子,醋制五味子以炮制6小时、米醋加入量为40-60g/100g五味子,酒制五味子以炮制4小时、黄酒加入量为10-20g/100g五味子,蒸制五味子以炮制6小时为最佳,炮制温度均为沸水浴炮制最好。结论:水浸率对各炮制因素具一定敏感性,可考虑作为炮制程度的一个辅助质量指标引入到五味子质量控制体系中来。  相似文献   
39.
五味子属(五味子科)分类系统的初步修订   总被引:5,自引:2,他引:3  
林祁  杨志荣 《植物研究》2007,27(1):6-15
通过对前人提出的五味子属(五味子科)分类系统的点评,根据五味子属植物的33个形态性状及其性状分析,经过分支分析,提出一个新的五味子属分类系统:将五味子属分为五味子亚属和团蕊五味子亚属;将五味子亚属分为多蕊五味子组、少蕊五味子组、中华五味子组和五味子组。编排了分亚属、组和种的检索表,对每个种上分类等级均列出其模式、异名和代表种。  相似文献   
40.
杨志荣  林祁 《植物研究》2007,27(6):661-663
采用常规制片方法首次对铁箍散(Schisandra propinqua(Wall.)Baill.)做了核型分析,结果表明铁箍散体细胞染色体数目为2n=28,核型公式为2n=2x=20m+8sm,染色体相对长度组成2n=28=2L+14M2+8M1+4S,染色体长度比为2.14,核型类型为2B型,核型不对称系数0.59,无次缢痕和随体。铁箍散的核型特点表明其在五味子属中处于较进化的地位。  相似文献   
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