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11.
Fritillaria thunbergii Miq. bulb-scale sections were cultured using Murashige and Skoog (MS) medium supplemented with NAA (1.62 M) and KN/2iP/BA (0.47–23.23 M).A high frequency of bulblets was developed from the scale sections and these bulblets have developed leaves and roots in 12 weeks of culture. An optimum of 13.7 bulblets developed from scale sections on solid MS medium supplemented with 1.62 M NAA and 4.65 M KN. Cultures incubated under cycles of 16 h white fluorescent light (40 mol m–2 s–1) and 8 h dark at a temperature regime of 25°C have produced optimal bulblets compared to cultures incubated under continuous dark at 25°C. The bulblets were harvested at the end of culture period and were given cold treatment at 5°C for 5 weeks and then transplanted to a potting mixture of peat moss, vermiculite and perlite (1:1:1). The bulblets, which were more than 10 mm in diameter, sprouted (100%) in 5 weeks of transplantation. 相似文献
12.
Wang Hsiang-Chih Chen Jen-Tsung Wu Shieh-Ping Lin Mei-Chun Chang Wei-Chin 《Plant Cell, Tissue and Organ Culture》2003,75(1):95-98
In order to establish and optimize an in vitro micropropagation protocol of Venus fly trap (Dionaea muscipula Ellis), a carnivorous plant, the effects of medium type, MS medium concentration, pH, and cytokinin and auxin types on shoot proliferation and root formation were investigated using 3-month-old shoots. The shoot proliferation was most effective in 2.3 M kinetin-supplemented 1/3MS medium at pH 5.5. The best conditions for rooting were 1/3MS medium supplemented with 0.5 M IBA. All subcultured shoots produced extensive root systems after 5–6 weeks culture. When plantlets after rooting were planted in plastic pots filled with 1:1 peat moss and sand, the survival rate of plantlets was almost 100%, exhibiting normal development. With subculture every 8 weeks, hundreds of the plants were propagated from a single plant within a year. 相似文献
13.
Summary Cell cultures of freshwater wetland monocots were regenerated, plants were grown in the greenhouse, and then established and
evaluated in wetlands. Typha (cattail), Juncus (rushes), Scirpus (bulrushes), and Carex (sedges) were studied because they are common, dominant, high biomass wetland-adapted plants, tolerant of chemically diverse
ecosystems. The goal was to define micropropagation and wetland establishment protocols. Tissue culture systems defined for
numerous monocot crop species can be readily applied to wetland plants, with a few modifications. Issues addressed were selection
of explant material, shoot and root regeneration conditions, culture age verses regenerability, greenhouse acclimatization
needs, plant uniformity and requirements for wetland establishment. In vitro-germinated seedlings were an excellent source of pathogen-free regenerable tissue. T. latifolia, T. angustifolia, and J. accuminatus were regenerated from callus induced in the dark with picloram, then transferred to medium with benzyladenine in the light
to promote shoot organogenesis. J. effusus, S. polyphyllus, and C. lurida could not be regenerated from callus, which turned black. They could be regenerated directly by culturing intact seedlings
directly on cytokinin media in the light. Shoots rooted with little or no auxin. J. effusus rooting was promoted by the addition of charcoal to the medium. Covering plants for the first 2 wk with plastic facilitated
greenhouse establishment. There were high rates of greenhouse and wetland survival. No abnormal plants were observed. These
regeneration systems could be utilized for the production of wetland plants for potential application in habitat restoration
and wetland creation, and would provide an alternative to field collection. 相似文献
14.
A.?R.?Koroch J.?Kapteyn H.?R.?Juliani J.?E.?SimonEmail author 《In vitro cellular & developmental biology. Plant》2003,39(4):415-418
Summary A method has been developed for the induction of adventitious shoots from leaf tissue of Echinacea pallida with subsequent whole-plant regeneration. Proliferating callus and shoot cultures were derived from leaf tissue explants
placed on Murashige and Skoog medium supplemented with 6-benzylaminopurine and naphthaleneacetic acid combinations. The optimum
shoot regeneration frequency (63%) and number of shoots per explant (2.3 shoots per explant) was achieved using media supplemented
with 26.6 μM 6-benzylaminopurine and 0.11 μM naphthaleneacetic acid. Rooting of regenerated shoot explants was successful on Murashige and Skoog medium, both with and
without the addition of indole-3-butyric acid. All plantlets survived acclimatization, producing phenotypically normal plants
in the greenhouse. This study demonstrates that leaf tissue of E. pallida is competent for adventitious shoot regeneration and establishes a useful method for the micropropagation of this important
medicinal plant. 相似文献
15.
S. R. Thengane D. K. Kulkarni K. V. Krishnamurthy 《In vitro cellular & developmental biology. Plant》1998,34(4):331-334
Summary Apical and axillary buds ofGlycyrrhiza glabra commonly known as licorice, a plant of repute in the Indian system of medicine, were used for induction of adventitious shoots.
For induction of multiple shoots, Murashige and Skoog’s (MS) medium with N6-benzyladenine (BA, 0.88–8.87 μM) was used. Reduction in major salts of MS medium enhanced the multiplication ratio up to 1∶10. Plants transferred to the
greenhouse showed 90% survival. The present work describes a stepwise protocol for production ofGlycyrrhiza glabra plants on simple minimal media, where very high multiplication rates with healthy root systems were obtained. Roots being
the organ of commercial importance, the protocol has tremendous potential. 相似文献
16.
Kim Yong Wook Youn Yang Noh Eu Rae Kim Joon Chul 《Plant Cell, Tissue and Organ Culture》1998,55(2):95-101
Embryogenic tissue was initiated using LM, LP and MS media from open-pollinated immature embryos of Larix leptolepis. The
initiation frequency varied with collection dates. The highest frequencies of embryogenic tissue initiation (60, 67 and 59%
on LM, LP and MS media, respectively) were observed from cones collected on July 30. At this time, all the excised embryos
were at the cotyledonary stage. ABA over a wide concentration and length of exposure range did not promote maturation, but
was beneficial in reducing precocious germination. Of over 400 plants regenerated, 72 were transplanted into soil mixtures
and to date, 69 of these (95%) have survived.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
17.
In vitro regeneration from leaf explants of Neoregelia cruenta (R. Graham) L.B. Smith,an endemic bromeliad from Eastern Brazil 总被引:1,自引:0,他引:1
Carneiro L.A. Araújo R.F.G. Brito G.J.M. Fonseca M.H.P.B. Costa A. Crocomo O.J. Mansur E. 《Plant Cell, Tissue and Organ Culture》1998,55(2):79-83
An efficient plant regeneration system was developed for the induction of direct shoot formation from leaves derived from
seedlings of Neoregelia cruenta, an endemic Bromeliaceae of Eastern Brazil. Shoot differentiation occurred directly from the
leaf bases. In vitro responses were influenced by seedling age and growth regulator combinations. Highest regeneration rates
were obtained from explants excised from 7-week-old seedlings cultured in the presence of 22 μM BA and 2.5 μM NAA. Shoot conversion
to whole plants was most effective in shoots formed in response to 4.4 or 8.8 μM BA combined with 2.5 μM NAA.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
18.
Micropropagation of Cypripedium macranthos var. rebunense through Protocorm-like Bodies Derived from Mature Seeds 总被引:1,自引:0,他引:1
Cypripedium macranthos var. rebunense is the most famous terrestrial orchid in Japan, since the variety has large beautiful yellowish-white flowers and is threatened
with extinction. Establishment of an efficient method for micropropagation is urgently needed. When imbibed mature seeds of
the orchid, that had been pre-chilled at 4°C for 3 months, were sown onto Hyponex-peptone medium that contained both α-naphthaleneacetic
acid (NAA) and cytokinin, protocorm-like bodies (PLBs) were formed from germinated seeds. Although the growth of PLBs was
very slow, plantlets were easily regenerated from the PLBs on hormone-free medium. The PLBs were subcultured eight times along
2 years without loss of ability to regenerate plantlets, and one aggregate of PLBs (ca. 5 mm in diameter) produced ca. 10
plants within a year. A reduction of commercial value through a large-scale micropropagation by this method will be able to
prevent illegal collection from the wild populations. 相似文献
19.
Extracellular Matrix in Early Stages of Direct Somatic Embryogenesis in Leaves of Drosera spathulata
The growth and water relations of Paulownia fortunei in photoautotrophic cultures (nutrient medium lacking sucrose and growth regulator) with CO2 enrichment (PWAH) or without CO2 enrichment (PWAL) were compared with those in photomixotrophic shoot (PWC; 30 g dm−3 sucrose and 0.3 mg dm−3 N6-benzyladenine) and root cultures (PWR; 0.3 mg dm−3 indole-3-butyric acid). The photoautotrophic and photomixotrophic cultures were incubated under photosynthetic photon flux
125 and 60 μmol m−2 s−1, respectively. 100 % sprouting and significantly higher number of shoots (1.6) were obtained with PWAH as compared to PWAL
and PWC. PWAH and PWAL stimulated spontaneous rooting from the cut end of axillary shoots. In PWAH, 84 % of shoots rooted
with an average of 5.9 roots per shoot and 4.0 cm of root length in 21 d. Rooting of photomixotrophic shoot cultures were
stimulated by an auxin treatment. In this case, 98.3 % of shoots were rooted with an average of 4.6 roots per shoot and 1.9
cm length. A microscopic observation on leaf abaxial surface prints from photomixotrophic shoot and root cultures showed widely
open (6 – 8 μm) spherical stomata (12 – 14 μm) and from photoautotrophic cultures elliptical stomata (10 – 12 μm) with narrow
openings (3 – 4 μm). Leaves from photomixo-trophic cultures had higher stomatal index as compared to photoautotrophic cultures.
The rate of moisture loss from detached leaves was not varying significantly in different cultures.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
20.
In vitro Growth and Shoot Multiplication of Achras zapota in a Controlled Carbon Dioxide Environment 总被引:1,自引:0,他引:1
The culture vessels with multiplying shoots of Achras zapota L. on Schenk and Hildebrandt (SH) medium containing 8.88 M 6-benzylaminopurine (BAP) with or without sucrose were kept under varied CO2 concentrations ranging from 0.6 to 40.0 g m–3 using different concentrations of sodium bicarbonate (NaHCO3), sodium carbonate (Na2CO3), potassium bicarbonate (KHCO3), and potassium carbonate (K2CO3) in small acrylic chambers. Complete absence of carbon source caused death of shoots within 20 d. Under elevated concentrations of CO2 (10.0 and 40.0 g m–3) the shoots grew photoautotrophically on sucrose-free medium. The growth of cultures was better at 40.0 g (CO2) m–3 than on 3.0 % sucrose under ambient air of growth room. However, the best response was obtained at 10.0 g (CO2) m–3 and 3.0 % sucrose where maximum number of shoots, shoot length, fresh and dry mass, total number of leaves and leaf area was observed. 相似文献