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131.
132.
地木耳提取物水溶液对花卉营养生长及开花的影响 总被引:2,自引:1,他引:1
在温室条件下,用1%的地木耳提取物水溶液对瓜叶菊(Seneciocruentus)、万寿菊(Tageteserecta)、矮牵牛(Petuniahybrida)、香石竹(Dianthuscaryophyllus)、一品红(Euphorbiapulcherrima)、仙客来(Cyclamenpersium)、一串红(Salviasplendens)等7种花坛花进行叶面喷施后,结果表明,7种花的株高、冠径、株鲜重、叶片数目、叶长、根长比对照均有显著增加(P<0.05);万寿菊,矮牵牛,一品红,一串红的平均株干重有显著增加,而瓜叶菊,香石竹,仙客来的平均株干重增加不显著(P>0.05);除了香石竹的叶宽有显著增加外,其余6种花的叶宽对1%地木耳提取物水溶液的反应不敏感;而7种花卉的叶厚都没有显著的变化。提取物水溶液还可促进花提早开花,增加花数目,并延长花期。 相似文献
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135.
Kim Moonza Kim Jinae Yoon Michung Choi Do-Il Lee Kwang-Min 《Plant Cell, Tissue and Organ Culture》2004,77(1):63-72
Anthers of Capsicum annuum L. were cultured on Murashige and Skoog (MS) medium containing 0.1 mg l−1 NAA and 0.1 mg l−1 kinetin. Inoculated anthers were subjected to 31 °C and development of microspores in anthers of varying stages was observed
cytologically using 4′-6-diamidino-2-phenylindol-2HCl (DAPI). Pepper was characterized by a strong asynchrony of pollen development
within a single anther. Percentage of pollen at different stages changed with the culture period, and the proportion of dead
pollen increased drastically from day 2 after culture. Microspores that were cultured at the late-uninucleate stage followed
one of two developmental pathways. In the more common route, the first sporophytic division was asymmetric and produced what
appeared to be a typical bicellular pollen. Embryogenic pollen was formed by repeated divisions of the vegetative nucleus.
In the second pathway, which occurred in fewer microspores, the first division was symmetric and both nuclei divided repeatedly
to form embryogenic pollen. In early-bicellular pollen, sporophytic pollen was produced through division of the vegetative
nucleus. In mid-bicellular pollen, the generative nucleus may undergo division to produce two or more sperm-like nuclei. However,
division of the generative nucleus alone to form the embryo was never observed. The anther stage optimal for embryo production
contained a large proportion (>75%) of early-binucleate pollen. Associations were found among the percentage of early-binucleate
pollen, the frequency of embryogenic multinucleate pollen, and the yield of pollen embryos. 相似文献
136.
Bruskova R. K. Zartdinova R. F. Satskaya M. V. Izmailov S. F. 《Russian Journal of Plant Physiology》2004,51(5):631-635
The organ topography of sucrose synthase and soluble acid invertase in pea seedlings at heterotrophic stage (3–14 days) was studied. Sucrose synthase was most active in the roots, with the highest activity on the 6–8th days. In the leaves, its activity decreased from day 3 to day 14. In the stems, sucrose synthase activity was at an invariantly low level. The patterns of sucrose synthase activity in etiolated and green plants were similar. As distinct from sucrose synthase, invertase activity was the highest in the stem, especially in etiolated plants. The peak of its activity was observed on the 6-8th days. In the leaves, invertase activity was lower but its pattern was the same. In the roots, acid invertase activity decreased from the 3rd day and did not depend on illumination. The conclusion is that differences in sucrose synthase and acid invertase activities in roots, leaves, and stem are determined by differences in the import of hydrolytic products of stored compound from the cotyledons as well as by different demands of these organs for these products for the processes of organ expansion and for the maintenance of organ metabolism. 相似文献
137.
以扁绒泡菌显型原质团为材料,进行细胞核的提纯、核骨架的制备及电镜观察。结果表明:用2mol/L NaCl+TritonX-100/NP40可得到具有复合纤维的核骨架,而用Lis + TritonX-100/NP40得到的核骨架具有核纤层,不使用RNase得到了具有网状的细胞核骨架,RNA在核骨架的结构形态中起重要作用。阐述了原质团中游离细胞核在细胞生物学研究中的意义。 相似文献
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139.
苏云金芽胞杆菌营养期杀虫蛋白基因的克隆及表达分析 总被引:9,自引:0,他引:9
选择本实验室分离的苏云金芽胞杆菌李氏亚种 (subsp. Leesis) 菌株YBT833、鲇泽亚种(subsp.Aizawai) 菌株YBT-1416和库斯塔克亚种(subsp. Kurstaki)菌株YBT1535为出发菌株,以营养期杀虫蛋白基因PCR扩增的特异片段为探针,进行总DNA酶切片段的Southern杂交定位。结果显示3株菌株的营养期杀虫蛋白基因,均位于经XbaI完全消化的4~5kb大小的DNA 片段上。将该区域DNA片段回收后克隆到pUC19载体,建立了3个较基因组文库小的亚基因组文库。通过菌落原位杂交筛选和酶切鉴定分别得到3个相应的营养期杀虫蛋白基因vip83、vip14和vip15,并对其测序。DNA序列比较发现基因vip83与已知营养期杀虫蛋白基因存在5个差异碱基。将vip83、vip14基因亚克隆到苏云金芽胞杆菌大肠杆菌穿梭载体pHT315, 分别得到重组质粒pBMB8901和pBMB8902。将它们电转化到vip-的B.t.受体菌BMB171和4Q7,获得了相应的工程菌BMB8901-171,BMB8902-171,BMB8901-4Q7和BMB8902-4Q7。SDS-PAGE电泳检测均有88kD大小的蛋白表达。生物测定结果亦表明了,营养期杀虫蛋白Vip83和Vip14对鳞翅目棉铃虫、小菜蛾和甜菜夜蛾的三龄幼虫均有一定的杀虫活性;其中对小菜蛾的毒力最高,LC50值分别为28.6,31.6,45.4和37.6μL/mL。该结果为构建高效广谱工程菌提供了实际材料和理论依据。
相似文献
140.
J Gerhart B Bast C Neely S Iem P Amegbe R Niewenhuis S Miklasz P F Cheng M George-Weinstein 《The Journal of cell biology》2001,155(3):381-392
The epiblast of the chick embryo gives rise to the ectoderm, mesoderm, and endoderm during gastrulation. Previous studies revealed that MyoD-positive cells were present throughout the epiblast, suggesting that skeletal muscle precursors would become incorporated into all three germ layers. The focus of the present study was to examine a variety of organs from the chicken fetus for the presence of myogenic cells. RT-PCR and in situ hybridizations demonstrated that MyoD-positive cells were present in the brain, lung, intestine, kidney, spleen, heart, and liver. When these organs were dissociated and placed in culture, a subpopulation of cells differentiated into skeletal muscle. The G8 antibody was used to label those cells that expressed MyoD in vivo and to follow their fate in vitro. Most, if not all, of the muscle that formed in culture arose from cells that expressed MyoD and G8 in vivo. Practically all of the G8-positive cells from the intestine differentiated after purification by FACS. This population of ectopically located cells appears to be distinct from multipotential stem cells and myofibroblasts. They closely resemble quiescent, stably programmed skeletal myoblasts with the capacity to differentiate when placed in a permissive environment. 相似文献