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831.
半夏属 (PINELLIA)的花粉粒和醇溶蛋白比较 总被引:5,自引:0,他引:5
继细胞学 〔1〕、形态学 〔2〕和比较解剖学 〔3〕的研究之后 ,我们又对半夏属的花粉粒和醇溶蛋白作了比较分析 ,旨在探讨这些性状的变异与分类学价值。1 材料和方法1 .1 实验材料 实验材料采自华东 3省的不同地区。在南京栽植至少 1年后 ,在盛花季节 ( 5月 )选有花植株的花粉和地下块茎作实验分析。各材料的种名、群体编号和产地见表 1。表 1 供实验用的半夏属 5种植物群体材料的来源Table1 Sources of material for experiment of the populationsbelonging to5species of Pinellia种名Species群体编号No.of populations产地Lo… 相似文献
832.
胡杨器官和体胚发生方式的植株再生 总被引:1,自引:0,他引:1
目的:为以胡杨为亲本的体细胞杂交育种奠定基础。方法:以胡杨苗叶片为外植体,通过器官和体胚两种不同发生方式建立了离体再生体系。结果:附加0.75mg/L BA、0.5mg/L NAA基本培养基及3w暗培养是愈伤组织诱导的最佳条件;附加0.25mg/L BA和0.1mg/L NAA的基本培养基上不定芽的诱导率最高;1/2大量元素的MS培养基附加0.1mg/l NAA、0.05mg/L和1.5%蔗糖对不定芽生根效果最好;诱导并筛选出的胚性愈伤组织在附加了0.5mg/L BA、0.5mg/L NAA的基本培养基上诱导获得大量胚状体,干化处理后大部分能经子叶胚期萌发成苗。结论:外植体的采集周期和培养条件影响胡杨离体叶片的形态发生途径。 相似文献
833.
834.
马尾松幼胚体细胞胚胎发生研究 总被引:2,自引:0,他引:2
本论文首次报道了马尾松(Pinus massoniana Lamb.)幼胚体细胞胚胎发生的完整发育过程,并对影响马尾松胚性愈伤组织诱导的因素如球果采种期、球果冷藏处理时间、外植体处理方式等进行了探讨,统计胚性愈伤组织诱导率,进行增殖评价,探讨ABA浓度梯度对马尾松体细胞胚分化成熟的影响,试验数据用SPSS16统计分析软件进行方差分析、差异显著性检验。结果表明:1)2008~2009连续2年内15个采种期得到的幼胚,胚性愈伤组织诱导和增殖有显著性差异,最适宜的马尾松球果采种期是6月下旬至7月下旬,诱导率在9.66%~22.59%之间;2)球果冷藏处理时间,对胚性愈伤组织诱导有显著性差异,其中4℃冷藏球果15d有利于幼胚胚性愈伤组织诱导;3)雌配子体包含幼胚的接种处理方式是可取的;4)胚性愈伤组织经稳定增殖培养后,转入分化成熟培养基,得到体细胞胚状体"爆发式"分化成熟,数量多,质量好。适宜体胚成熟转化的培养基为:成熟LP培养基添加ABA5.0mg·L-1+60.0g·L-1蔗糖,并附加L-谷氨酰胺和水解酪蛋白;5)成熟体细胞胚在无激素萌发型LP培养基上正常萌发,并转化为结构完整的小植株。本研究首次建立了马尾松幼胚体细胞胚胎发生技术平台,为马尾松遗传改良种质创新、缩短育种周期奠定了研究基础。 相似文献
835.
836.
Summary Two sugarbeet (Beta vulgaris L.) genotypes, REL-1 and REL-2, were used to measure the level of somatic embryo and shoot production from hormone-autonomous
callus plated under varied nutrient medium combinations of abscisic acid with the growth regulators 6-benzyladenine, 1-naphthaleneacetic
acid, or 2,4-dichlorophenoxyacetic acid, with eight sole nitrogen sources, or with different sucrose concentrations. Clone
REL-2 produced embryos up to 35-fold more frequently than clone REL-1. Inclusion of abscisic acid at some concentrations consistently
improved embryo production in all experiments and was observed to stimulate shoot production. At some concentrations, 1-naphthaleneacetic
acid as well as urea and glutamine stimulated greater embryo production over the control, but only for REL-1, for which there
was greater room for improvement. Three and five percent sucrose were superior to 1, 7, and 9%. Higher initial 6-benzyladenine
concentration [in the range 0, 0.1−1.0 mg/L (0.44−4.44 μM)] was associated with lower embryo production but greater shoot regeneration for both clones. REL-2 was significantly better
than REL-1 in shoot regeneration. The range of embryo production was more than 35-fold between genotypes, whereas the range
of physiological effects was no greater than 10-fold. REL-2 has been released to sugarbeet researchers because of its superior
embryogenic and shoot regeneration abilities for application in biotechnology. 相似文献
837.
Summary Direct delivery of DNA into embryogenic pollen was used to produce transgenic plants in tobacco. A plasmid bearing the ß-glucuronidase (GUS) marker gene in fusion with the 35S-promoter was introduced by microprojectile bombardment into mid-binucleate pollen of Nicotiana tabacum that had been induced to form embryos by a starvation treatment. In cytochemical expression assays, 5 out of 104 pollen grains were GUS+. Visual selection by staining with a non-lethal substrate for GUS was used to manually isolate transformed embryos. From the initial population of embryogenic GUS+ pollen, 1–5% developed into multicellular structures and 0.02% formed regenerable embryos. Two haploid transformants were regenerated. GUS expression was detected in different parts of the plants, and Southern analysis confirmed stable integration of the foreign DNA. Diploidisation was induced by injection of colchicine into the stem near adventitious buds. Offspring from selfings and backcrosses of one transformant were tested for GUS expression and by Southern blots. All F1-plants were transgenic, in accordance with Mendelian inheritance.Abbreviations GUS
ß-glucuronidase
- CaMV
Cauliflower Mosaic Virus
- MCS
multicellular structure
- NPTII
neomycin phosphotransferase
- PEG
polyethylene glycol
- X-gluc
5-bromo-4-chloro-3-indolyl glucuronide
- DAPI
4,6-diamidino-2-phenylindole
- Tris
Tris(hydroxymethyl)aminomethane hydrochloride
- EDTA
ethylenedinitrilo tetraacetic acid, disodium salt dihydrate 相似文献
838.
839.
John G. Carman 《In vitro cellular & developmental biology. Plant》1990,26(8):746-753
Summary Plants develop from meristems where cells proliferate and are partitioned into layers that eventually differentiate to form
the various tissues and organs of the plant. A phenomenon unique to certain plant tissues is the ability to inducede nova a range of developmental patterns, including embryogenesis. The temporal and spacial distribution of these developmental
competencies suggests that regulatory proteins, rather than a lack of signals or signal receptors, shield specific developmental
genes from signals that otherwise would confuse development. Studies involving embryogenic cells demonstrate that they are
not strongly shielded from developmental signals, thus they are not determined. Furthermore, the normal development of zygotic
and somatic embryos is readily perturbed by abnormal physicochemical environments. This suggests that embryogeny remains developmentally
plastic until differentiation is largely completed. The ability to induce somatic embryogenesis from specific tissues by specific
signals is providing opportunities to further the molecular characterization of the menagerie of genetic regulation involved
in development.
Much of this review was presented at a Moet-Hennessy Louis Vuitton sponsored conference, Control of Morphogenesis in Plants,
Aix Les Bains, France, September, 1989. Studies in our laboratory were supported in part by grants from the National Aeronautics
and Space Administration (Cooperative Agreement No. NCC2-139), the Utah State University Biotechnology Center, and by the
Utah Agricultural Experiment Station, Utah State University, Logan, UT 84322-4845 (approved as journal paper no. 3928). 相似文献
840.
Segments taken from young leaves of an orchid (Oncidium Gower Ramsey) produced clusters of somatic embryos directly from epidermal and mesophyll cells of leaf tips and wound surfaces
without an intervening callus within 1 month when cultured on a GelriteTM-gelled 1/2-MS basal medium supplemented with a low dosage (0.3–1 mg/l) of thidiazuron. Subculturing of these embryo clusters
produced more embryos and subsequent plantlet formation on the same medium. The high-frequency embryogenesis of these leaf
cells in this orchid is strong evidence of their totipotency, and further modification of the protocol for plant formation
could be useful for the mass propagation and transformation of selected elite lines.
Received: 16 September 1998 / Revision received: 16 February 1999 / Accepted: 26 February 1999 相似文献