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111.
The aim of this study was the evaluation of membrane permeability of callus cells of several Polish meadow fescue cultivars,
which were treated with toxins of two leaf spot pathogens Bipolaris sorokiniana and Drechslera dictyoides. Fungus metabolites were obtained by the method described by Lepoivre et al. (1986). Calli of cultivars ‘Skrzeszowicka’, ‘Skawa’, ‘Westa’, POB 282, POB 383, KOA 186 have been selected on medium with
metabolites for two weeks. Next the conductivity test of electrolyte leakage and of total ion contents in the examined tissue
was done. On the base of this data the membrane permeability coefficients for each cultivar were calculated. Toxins of B. sorokiniana damaged the cell membranes more strongly than metabolites of D. dictyoides. The significant differences of several objects sensitivity to the influence of B. sorokiniana metabolites were stated. These differences were not observed in the case of the influence of D. dictyoides metabolites on the examined tissue. 相似文献
112.
Takashi Fujita Hitoshi Hatamoto Mari Miyamoto Taisuke Iwasaki Shin-ichi Takafuji 《Biotechnology letters》1998,20(11):1057-1061
Cell suspensions derived from Acer nikoense callus, not containing (S)-rhododendrol, converted 4-(p-hydroxyphenyl)-2- butanone into (R)-, (S)-rhododendrol and their glycosides. (R)- and (S)-rhododendrol formed was only detected in the culture medium and their glycosides only in the cells. The former compound disappeared within a short time and the latter one also tended to decrease during prolonged culture. Quantitative analysis of rhododendrol glycosides in the callus showed that most of them were (S)-rhododendrol 2-O--D-glucopyranoside and its content was much lower than that of the original plants. © Rapid Science Ltd. 1998 相似文献
113.
Plant regeneration from protoplasts isolated from friable embryogenic callus of cassava 总被引:2,自引:0,他引:2
E. Sofiari C. J. J. M. Raemakers J. E. M. Bergervoet E. Jacobsen R. G. F. Visser 《Plant cell reports》1998,18(1-2):159-165
Protoplasts were isolated from friable embryogenic callus (FEC) and from suspensions derived from FEC of cassava genotype
TMS60444. Suspensions yielded the highest number of protoplasts (1.5×106 protoplasts/g fresh weight). Protoplasts plated at a density of 105–106/ml in a medium supplemented with 0.5 mg/l α-naphthaleneacetic acid and 1 mg/l zeatin began dividing after 3 days, and after 30 days this resulted in an absolute plating
efficiency as high as 2.5%. After 2 months of culture, 60% of the developed calli were highly friable and in appearance identical
to the original FEC. The protoplast derived FEC was first purified through two rounds of selection of 3 weeks each before
beeing cultured for regeneration of plants. This was done by culturing the protoplast-derived FEC for 11 weeks on maturation
medium, yielding a maximum of 184 organized embryos per 10.000 initially cultured protoplasts. Most of the organized embryos
were torpedo shaped and matured after they had been isolated from the calli and transferred to fresh medium. Mature embryos
were multiplied by secondary somatic embryogenesis at high efficiency (>90%) on a medium supplemented with 8 mg/l 2,4-dichlorophenoxyacetic
acid. About 30% of the mature secondary somatic embryos developed into shoots after transfer to a medium supplemented with
1 mg/l N6-benzylaminopurine (BAP). Shoots rooted readily on a medium without BAP.
Received: 30 August 1996 / Revision received: 9 June 1997 / Accepted: 1 October 1997 相似文献
114.
不同理化因子对雪莲培养细胞中黄酮类形成的影响 总被引:26,自引:2,他引:24
研究了不同理化因子对水母雪莲(Saussurea medusa Maxim)愈伤组织生长及黄酮类化合物生物合成的影响。结果表明,有利于细胞生长及黄酮形成的合适温度为25℃。白光对愈伤组织生长无促进作用,但有利于黄酮的形成。培养基中添加1mg/L NAA和O.2mg/L的KT组合对细胞的生长较有促进作用。5%蔗糖和1%葡萄糖的组合有利于细胞的生长和黄酮的形成。用60C0-γ射线辐照愈伤组织,在剂量为4000Gy的条件下,获得一个合成黄酮能力高于原愈伤组织70%的细胞系。用高效液相和紫外分光光度法,测定离体培养光照条件下干细胞总黄酮的含量为3.2%,是暗培养的4.4倍。培养温度25℃时干细胞黄酮的含量为2.02%,分别为20℃,35℃时的5倍和3.2倍。 相似文献
115.
裸燕麦胚性愈伤组织培养及悬浮系的建立 总被引:12,自引:1,他引:11
裸燕麦成熟胚在IN6培养基上诱导培养,初始愈伤组织为白色、瘤状、外软内硬、易分化植株的非松脆类型。当在IM1~IM4培养基上进行循环式调控培养,经7~8个月,初始愈伤组织转变为浅黄色、小颗粒状、生活力强的松脆型胚性愈伤组织。将胚性愈伤组织置于液体培养基中悬浮培养,得到分散性好、生长快的悬浮细胞系。悬浮系经分化培养获得了再生植株,移栽成活率达95%以上。 相似文献
116.
117.
Vishwanath M. Patil 《In vitro cellular & developmental biology. Plant》1998,34(3):240-243
Summary The purpose of this study was to developin vitro techniques for conserving wild and endemic species ofCeropegia by mass multiplication for subsequent reintroduction in their natural habitat. Micropropagation involving a combination of
axillary bud culture, shoot multiplication, somatic embryogenesis andin vitro tuber formation forCeropegia jainii, a rare plant of the Indian sub continent,C. bulbosa var.bulbosa andC. bulbosa var.lushii, common species, was developed. Nodal explants from all species were cultured on 0.5 MS medium with 8.8 μM (2 mg·l−1) N6-benzyl aminopurine (BA) to regenerate the axillary buds. These produced multiple shoots when transferred to multiplication
medium consisting of 0.5 MS medium with 2.2 μM (0.5 mg·l−1) BA, or microtubers when transferred to 0.5 MS medium with 22.2 μM (5 mg·l−1) BA and 23.2 μM (5 mg·l−1) kinetin.In vitro flowering occurred inC. jainii and not in the other two varieties when the plants were cultured on multiplication media with spermine at 0.25 μM (50 μg·l−1) as an additive. Shoot pieces produced callus on MS medium with 9.05 μM (2 mg·l−1) 2,4-dichlorophenoxy acetic acid. Regeneration of the calli by somatic embryogenesis was achieved when they were transferred
to 0.5 MS medium with 2.2 μM (0.5 mg·l−1) BA. Rooting of the shoots was possible both byin vitro andex vitro means. 相似文献
118.
Effects of cytokinin on adventitious root formation in callus cultures ofVigna unguiculata (L.) walp
Woong-Young Soh Pil-Son Choi Duck-Yee Cho 《In vitro cellular & developmental biology. Plant》1998,34(3):189-195
Summary Yellowish compact callus, induced from cowpea hypocotyls on Murashige and Skoog(MS) medium (1962) containing 0.2 mg/l(0.93
μM) kinetin and 0.4 mg/l (1.81 μM) 2,4-dichlorophenoxyacetic acid (2,4-D), was subcultured on MS medium containing cytokinin alone, auxin alone, or auxins
plus cytokinins in order to determine the effect of cytokinins on root organogenesis in callus cultures. The callus actively
proliferated on the same medium but did not show any organogenic activity macroscopically as well as microscopically. On medium
with N6-benzyladenine (BA) and 1-naphthaleneacetic acid (NAA), the yellowish compact callus first changed to pale green compact callus
and then many green spots appeared on its surface under light culture. But the yellowsih compact callus remained yellowish
and white spots appeared on its surface in dark culture. These spots gradually became white nodular structures. Adventitious
root formation from the nodular structures occurred not only on the same medium, but also on medium with either auxin or cytokinin
but not both. Yellowish compact callus on medium with auxin alone was transformed to yellowish friable callus, which did not
develop adventitious roots. The yellowish friable callus could gain rhizogenic activity only after morphological modification
to pale green compact callus on medium with auxin plus cytokinin. The modified callus did not form adventitious roots on medium
with auxins but only with cytokinins. Therefore, it is suggested that cytokinins have stimulating effects on root formation
from callus that previously did not show rhizogenic activity on medium with auxins alone. In addition, the rhizogenic potential
of cowpea callus was discriminated from that of leaf explants, which formed adventitious roots directly on medium with auxin
alone. 相似文献
119.
百草枯和苯甲酸钠对渗透胁迫下抗旱性不同玉米品种愈伤组织的影响 总被引:1,自引:1,他引:0
李玲 《植物生理与分子生物学学报》1998,(4)
两个品种玉来愈伤组织经0.5和5mmol/L的百草枯处理3h后,在渗透胁迫(PEG6000-0.5MPa溶液)下处理24h,电解质泄漏率增加;H2O2和MDA积累;AsA和CAR含量的减少加剧。0.5和5mmol/L的苯甲酸钠减轻渗透胁迫诱导的氧化伤害,促进CAT活性的增加;使SOD、GR、AP和POD能维持较高的活性;AsA和CAR含量降低的幅度减小。抗旱性强的品种PAN6043愈伤组织抗氧化胁迫和渗透胁迫能力强于抗旱性弱品种SC701,并与合高活力抗氧化系统密切相关。 相似文献
120.
Aribaud Marcel Kevers Claire Martin-Tanguy Josette Gaspar Thomas 《Plant Cell, Tissue and Organ Culture》1998,55(2):85-94
Foliar discs (8 mm diameter) from expanding leaves of the middle part of vegetative shoots of Chrysanthemum morifolium Ramat
raised in vitro were induced to form directly on specific media in vitro either roots or vegetative buds, or callus. The budding
programme, on its specific medium, was deviated to callus formation by the addition of 2 mM β-OH-E (β-OH-ethyldrazine, an
inhibitor of diamine oxidase). Conversely vegetative buds instead of callus were formed on the callus medium in the presence
of 2 mM DFMO (difluoromethylornithine, an inhibitor of ornithine decarboxylase). Callus formation was characterized by high
accumulation of free and particularly conjugated polyamines (PA), very low or undetectable activities of diamine- and polyamine
oxidases, and transglutaminase. DFMO-deviation of callus initiation in favour of bud formation lowered the accumulation of
PA and increased the activity of amine-oxidases. The high catabolism of PA in the organogenic (rooting, budding) programs
was questioned as to its role in developmental processes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献