全文获取类型
收费全文 | 205篇 |
免费 | 7篇 |
国内免费 | 18篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 4篇 |
2020年 | 4篇 |
2019年 | 10篇 |
2018年 | 2篇 |
2017年 | 5篇 |
2016年 | 5篇 |
2015年 | 7篇 |
2014年 | 5篇 |
2013年 | 13篇 |
2012年 | 11篇 |
2011年 | 10篇 |
2010年 | 5篇 |
2009年 | 10篇 |
2008年 | 9篇 |
2007年 | 9篇 |
2006年 | 11篇 |
2005年 | 16篇 |
2004年 | 6篇 |
2003年 | 14篇 |
2002年 | 5篇 |
2001年 | 3篇 |
2000年 | 8篇 |
1999年 | 8篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 7篇 |
1993年 | 2篇 |
1992年 | 6篇 |
1991年 | 4篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 4篇 |
1974年 | 1篇 |
排序方式: 共有230条查询结果,搜索用时 62 毫秒
31.
32.
人参毛状根培养过程中对活性氧清除能力的动态变化 总被引:4,自引:2,他引:2
采用化学发光法 ,考察了人参 (PanaxginsengC .A .Mey)毛状根培养过程中对 3种重要活性氧ROS(O2÷、OH·、H2 O2 )清除能力的动态变化 ,发现在毛状根生长对数期时对 3种ROS都有很强的清除能力 ,而在生长停滞期较低 ,符合人参毛状根生长的S型曲线 ,印证了人参毛状根的生长和衰老过程。 相似文献
33.
Babar Maqbool Yong Wang Xuemei Cui Shanshan He Ran Guan Shenghao Wang Yuemin Wang Songhua Hu 《Microbiology and immunology》2019,63(7):269-279
Pseudorabies, a herpesvirus infection, is mainly controlled by using attenuated live vaccines. In this study, the effect of ginseng stem and leaf saponins (GSLS) in combination with selenium (Se; in the form of sodium selenite) on vaccination against attenuated pseudorabies virus (aPrV) was evaluated. It was found that GSLS and Se have an adjuvant effect and that a combination of GSLS and Se stimulates significantly enhanced immune responses than does GSLS or Se alone. Following oral administration of GSLS, mice immunized with an attenuated PrV vaccine diluted in Se‐containing physiological saline solution (PSS) provoked a significantly stronger gB‐specific serum antibodies response (IgG, IgG1 and IgG2a), enhanced lymphocyte proliferation and cytolytic activity of NK cells, along with higher production of cytokines (IFN‐γ, IL‐12, IL‐5 and IL‐10) by splenocytes. Notably, the combination of GSLS and Se conferred a much higher resistance to fPrV challenge after immunization of the mice with aPrV vaccine. This study offers convincing experimental evidence that an injection of Se with oral GSLS is a promising adjuvant combination that improves the efficacy of vaccination against PrV and deserves further study regarding improvement of responses to other animal vaccines. 相似文献
34.
Cotyledon explants of Panax ginseng zygotic embryos directly produced somatic embryos on Murashige and Skoog medium without growth regulators. Somatic embryos were formed only near the proximal excised region of cotyledons. Multiple and/or single embryos were formed and the frequency of these formations differed according to the degree of maturity of the zygotic embryos used as the explant source. When cotyledon explants pre-plasmolysed (1.0 M sucrose for 24 h), the frequency of single embryo formation was enhanced regardless of cotyledon maturity. In addition, the distribution pattern of somatic embryos changed markedly because the embryos were formed over the whole surface of the cotyledons. Histological observation revealed that plasmolyzing pretreatment broke the plasmodesmatal connection between cells and when the embryogenic cell divisions commenced, plasmodesmatal strands were hardly observed except for newly formed cell walls. This indicates that the enhanced single embryo formation over the entire surfaces of cotyledon explants might be the result of an interruption of cell–cell interaction by plasmolyzing pretreatment. 相似文献
35.
林下人参生理特性和生长与林内生态因子的关系 总被引:7,自引:0,他引:7
结合模拟试验,对林下人参的生理活动及生长过程与林内生态因子的关系进行 了观测研究.结果表明,林内光照、水分、温度等因子与林下人参生长的关系极为密切.一 般林内光照在中等条件下,即相对光照在10~35%左右.林分郁闭度约0.6~0.8,土壤含 水量在 35~40%时人参生长最好;林下人参的物候进程及生长与温度的关系密切.林内 温度在5℃左右人参芽胞开始萌动,15℃左右地上茎高生长进入速生期,6月上旬生长停 止.因此,人为调节各种生态因子在适宜的范围内有利于林下人参的生长. 相似文献
36.
Jung JA Jhang E. John Staba Jung Yun Kim 《In vitro cellular & developmental biology. Plant》1974,9(4):253-259
Summary Roots, stems, or leaves of American (Panax quinquefolium) and Korean (Panax ginsing) ginseng were grown as callus or supension tissue cultures. Tissue cultures ofP. ginseng would occasionally form plantlets. The fundamental chemical composition, inorganic analysis, and saponin (panaquilin) content
of American and Korean ginseng plants and tissue cultures were determined. The crude saponin content is very similar to, but
approximately one-half (1.3%, fresh weight) of that present in ginseng roots. Two-dimensional thin layer chromatographic analysis
revealed minor differences in the panaquilins present in American and Korean ginseng tissue cultures. The sapogenin, panaxadiol,
was isolated from Korean ginseng callus. 相似文献
37.
Identification and differentiation of Panax species using ELISA, RAPD and eastern blotting 总被引:1,自引:0,他引:1
Immunochemical and genetic methods have been developed in order to distinguish Panax spp. With the aim of establishing immunochemical methods, two hybridomas (3H4 and 5H8), each secreting a monoclonal antibody (MAb) against proteins of Panax ginseng, were prepared by fusing splenocytes immunized with two kinds of ginseng water-soluble fractions and a hypoxanthine-thymidine-aminopterin-sensitive mouse myeloma cell line, P3-X63-Ag8-U1. MAb 3H4 cross-reacted with four Panax spp., whereas the MAb 5H8 cross-reacted with P. ginseng in the enzyme-linked immunosorbent assay (ELISA). ELISA and western blotting methods using a ginseng water-soluble fraction as the solid-phase antigen were developed for the unambiguous authentication of P. ginseng. A combination of random amplified polymorphic DNA (RAPD) and eastern blotting analyses using anti-ginsenoside Rb1 and Rgl monoclonal antibodies was used for the identification of P. notoginseng, P. quinquefolius and P. japonicus. RAPD can be used to differentiate the species of Panax from each other. An important parameter used for differentiating P. notoginseng is the absence of ginsenoside Rc in the extract of P. notoginseng with eastern blotting. The combination of these methods enabled a reliable identification of Panax spp. 相似文献
38.
American ginseng root (Panax quinquefolius) has a number of purported therapeutic effects, including inhibition of cancer cell proliferation. The ability of environmentally relevant heavy metals to alter ginseng effects on cancer cell growth was the subject of this study. A water extract of American ginseng root was applied alone or in combination with physiologically relevant doses of either lead (Pb) or arsenite to MCF-7 breast cancer cells in vitro and effects on cell proliferation were determined. Ginseng alone produced a significant dose-dependent inhibition of MCF-7 cell proliferation starting at 0.5 mg ml(-1). Treatment of MCF-7 cells with 2.5 microM arsenite significantly decreased MCF-7 cell proliferation (p < 0.01). When cells were treated with arsenite (1.25 or 2.5 microM) in combination with ginseng extract (0.5 mg ml(-1)), there was an apparent synergistic inhibition of cell proliferation. Treatment of MCF-7 breast cancer cells with 50 microM Pb significantly decreased cell proliferation relative to control (p < 0.01), and concomitant ginseng and Pb treatment did not lead to a further decrease. These results suggest that contaminant heavy metals, some of which have been detected in ginseng root extracts or commercial ginseng preparations, may alter the biological activity of ginseng. 相似文献
39.
贮运温度对盆栽榕树落叶及抗性生理的影响 总被引:2,自引:0,他引:2
以盆栽榕树为试验材料,探讨不同贮运温度对盆栽榕树落叶及抗性生理的变化。结果表明,不同贮运温度对盆栽榕树落叶及抗性生理影响显著。与(16±1)℃及(19±1)℃比较,(10±1)℃及(13±1)℃的贮运温度能显著减缓叶片的细胞质膜透性、降低丙二醛(MDA)含量,提高过氧化物酶(POD)和过氧化氢酶(CAT)活性,增加可溶性糖和可溶性蛋白含量,延缓叶绿素的降解速度,落叶率低。在贮运36 d时,(10±1)℃和(13±1)℃贮运温度的落叶率均在16%以下,达到出口要求,而两者间的落叶率差异不显著。 相似文献
40.
Hairy roots of Panax ginseng were obtained after root disks were infected with wild-type strain Agrobacterium rhizogenes 15834. Three lines of hairy roots with different pigmentation were selected. Embryogenic callus was induced on Murashige
and Skoog medium containing 1.0 mg/l 2,4-D. The frequency of embryogenic callus formation was 37.4% in a line with red pigmentation.
Somatic embryo development from embryogenic callus was efficiently achieved by lowering the concentration of 2,4-D (0.5 mg/l).
After the germination of somatic embryos on medium with 10 mg/l GA3, the embryos were transferred to 1/2-MS medium without GA3. The transformed ginseng plantlets had an actively growing root system with abundant lateral roots. The phenotypical alteration
of transformed ginseng plants might be valuable character for increasing root yield.
Received: 27 March 1999 / Revision received: 18 May 1999 / Accepted 8 July 1999 相似文献