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71.
Bulb rot causes a great loss of rare perennial medicinal Fritillaria przewalskii Maxim., which is exacerbated with growth year and seriously constrains the plant productivity, but the pathogens responsible for the disease were still unknown. In this paper, we attempted to explore the potential pathogens leading to bulb rotting and their occurrence patterns in artificial domesticated F. przewalskii. Fungus strains were isolated from the bulb rot spot of the 3‐ to 5‐year‐old diseased F. przewalskii plants by tissue separation, further assayed for pathogenicity according to Koch's law and finally identified by both morphological and molecular methods. Seven pathogenic strains (F1‐F7) were detected in 5‐year‐old rot bulbs, six (F1‐F6) in 4‐year‐old rot bulbs and four (F1, F2, F5, F6) in 3‐year‐old rot bulbs. All of the strains were able to infect bulbs by stabbing and some exhibited varying levels of aggressiveness. Relative to the non‐stabbing controls, the bulbs stab‐inoculated with F5, F2, F7, F4, F1, F6, and F3 showed 76.65%, 75.15%, 71.44%, 40.37%, 39.09%, 36.87%, and 34.93% rot after 8 days, respectively. Phylogenetic analysis revealed that these seven strains were clustered into Bionectria ochroleuca (F1, F3, F4), Fusarium oxysporum (F2, F7), Fusarium tricinctum (F5), and Clonostachys rosea (F6). The two species of Fusarium had the strongest pathogenicity, followed by Bionectria ochroleuca and Clonostachys rosea. Although leading to low bulb rot incidence by stab inoculation, F1 showed the highest isolation rate (48.9%) among all strains. Thus, the edible and medicinal bulbs of F. przewalskii are susceptible to synergetic contamination by these seven pathogens at some point after their third year of growth, which has contributed to the species endangered status, with the two strains of Fusarium being the predominant pathogens. To our knowledge, this is the first report on the seven strains of four fungal species causing F. przewalskii bulb rot in China. 相似文献
72.
目的:观察复方浙贝药物血清抑制耐顺铂的小鼠淋巴细胞系(L1210/CDDP)增殖和诱导凋亡效应,并在此基础上探讨复方浙贝颗粒逆转白血病细胞多药耐药机制。方法:MTT法测定不同浓度组复方浙贝颗粒含药血清抑制L1210/CDDP增殖;Annex-in-V/PI双染经流式细胞仪(FCM)定量检测其含药血清诱导L1210/CDDP细胞早期凋亡率。结果:不同剂量复方浙贝颗粒含药血清组均具有抑制L1210/CDDP细胞增殖效应,对其凋亡抑制率分别为:29.27%(高剂量组)、31.78%(中剂量组)、21.20%(低剂量组)、25.31%(阿霉素组);实验各组的A570nm与空白对照组比较明显下降(P〈0.01)。经FCM双荧光法检测其能够诱导L1210/CDDP细胞早期凋亡,实验各组凋亡率分别为:55.12%(中剂量血清组)、34.23%(低剂量组)、25.69%(高剂量组),24.65%(空白血清组)。结论:复方浙贝颗粒含药血清能够明显抑制L1210/CDDP细胞增殖,并能诱导其凋亡。 相似文献
73.
Phytochemical investigation of the bulbs of Fritillaria hupehensis resulted in the isolation and structural elucidation of four new steroidal penta- and hexacyclic veratraman- and cevan-based alkaloids, respectively, compounds 1-4. They were obtained together with the known constituents ebeinine (5) and zhebeinine (6), which were isolated for the first time from this plant. The structures of the new isolates were established by spectroscopic and mass-spectrometric analyses, in combination with chemical methods. All compounds were assayed for their cytotoxic effects towards HeLa and HepG2 cell lines. Compounds 1 and 2 showed significant inhibitory effects against both types of tumor cells, with IC(50) values in the range 2.52-0.23 microM, similar as those for 5-fluorouracil used as positive control. 相似文献
74.
为了了解暗紫贝母对资源变化的适应策略,本研究通过田间控制试验,研究了遮光和施氮对暗紫贝母生物量、生物量分配,以及叶、根C、N状态的影响。结果表明:遮光和施氮处理后,暗紫贝母生物量均减少;遮光下叶片的生物量分配相对增加,叶根生物量比显著升高(P<0.05),但施氮处理下叶根生物量比的变化不明显;遮光和施氮后,暗紫贝母叶、根N含量均显著升高(P<0.05),叶片和根的C:N显著降低(P<0.05);相关分析显示,叶片N、C:N与暗紫贝母总生物量、叶根生物量比有极显著的相关性(P<0.01)。本研究表明,与生物量分配相比,C-N平衡,尤其是叶片的C:N比能更好的解释暗紫贝母对资源变化的适应。 相似文献
75.
在陕西省太白县采集到伊贝母(Fritillaria pallidiflora Schrenk.)的菌核病致病真菌,伊贝母葡萄孢盘 Botryotinia fritillarii-pallidiflori Q.T.Chen et J.L.Li sp.nov.新种。并报道了其形态特征及其与椭圆葡萄孢 [Botrytis elliptica(Berk.)Cooke]和驴蹄草葡萄孢盘(Botryotinia calthae Hennebert et Elliott)的区别。 相似文献
76.
伊贝母黄化茎段培养在含有NAA 0.5 mg/1 6BA 0.2 mg/l的MS培养基上。鳞茎发生过程中过氧化物酶活性及同工酶带逐渐增加。AMD和CHM都抑制鳞茎的发生,茎段培养后最初12 h对AMD最为敏感,以后敏感程度逐渐减弱,茎段对CHM的敏感程度更强,敏感时期亦更长。茎段培养后过氧化物酶活性和同工酶的出现和增加受到CHM的抑制,而不受AMD的抑制。 相似文献
77.
78.
Aleksandra J. Lukaszewska Maria Witomska Jacqueline Bianco Philippe Barthe 《Acta Physiologiae Plantarum》1998,20(3):241-244
Correlation between ABA content in “mother” tissue and subsequent regeneration ability of Fritillaria imperialis cultured in vitro was investigated. In every experiment regeneration was always most efficient from plant material containing
the lowest amount of free ABA: a leafy stem part, bulbs used for micropropagation in October and those stored two months at
30 °C prior to in vitro culture. However, no direct correlation between the absolute amounts of ABA and percentage of regeneration was found. 相似文献
79.
80.
中国长江中下游地区贝母属的修订 总被引:7,自引:0,他引:7
本文对长江中下游地区的贝母属进行了修订,确认该地区有3种1变种,新归并14种5变种。 相似文献