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1.
植物离体培养中器官发生调控机制的研究进展   总被引:75,自引:0,他引:75  
本文就离体培养的植物组织对生长调节物质的吸收和代谢,外源生长调节物质对内源激素水平的影响,内源激素对细胞脱分化和再分化的调控,生长素和细胞分裂素基因与器官发生的关系,与器官发生有关的基因和特异蛋白等问题的研究进展进行了评述,并对下一步研究提出了自己的看法。  相似文献
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以作者自己的工作为背景,结合国内外近几年的有关报道,综述了几种外源和内源激素对植物体细胞胚胎发生的诱导与调节作用。外源生长素和细胞分裂素是诱导离体培养细胞分化与增殖所必需的,2,4-D是诱导胚性愈伤组织的重要激素。在体细胞胚胎发生中内源激素含量和代谢的平衡起着关键的作用,而且外源和内源激素对诱导体细胞胚胎发生起相互调节作用。ABA在提高体细胞胚胎发生频率和质量上具有重要作用,同时,外源与内源ABA对体细胞胚胎发生起相互促进作用。本文还较为深入地讨论了这些激素诱导体细胞胚胎发生的可能作用机制。 Abstract:The paper summarizes the induced and regulatory effects of a few exogenous and endogenous hormones in plant somatic embryogenesis by our studies and related international reports.The exogenous auxin and cytokinin are necessary to induced differentiation and proliferation of cells of culture in vitro.2,4-D is an important hormone of induced embryogenic calluses.The contents and the metabolic balances of endogenous hormones have key effects for somatic embryogenesis.In addition,the exogenous and endogenous hormones have mutual regulatory effects for somatic embryogenesis.ABA has an important effect to improving the frequency and quality of somatic embryogenesis.Meanwhile,the exogenous and endogenous ABA have mutual promoted effects for somatic embryogenesis.The paper discusses possible mechanism of hormones-induced somatic embryogenesis in a deep-going way.  相似文献
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植物耐盐性机理研究进展   总被引:43,自引:3,他引:40       下载免费PDF全文
廖岩  彭友贵  陈桂珠 《生态学报》2007,27(5):2077-2089
在盐胁迫下环境中某些植物会在发生一些变化。从生理学、生物化学、盐胁迫分子学机制的角度对植物对盐胁迫的反应研究进行了回顾,并提供了一些目前知识水平上能增加植物盐耐性的方法。解释了在盐胁迫下植物的离子吸收、相溶性物质、抗氧化酶、植物激素、光合作用等方面的变化规律,其中也有耐盐植物功能调节的研究,这有助于从多学科研究的角度评估盐胁迫的生态重要性。  相似文献
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Summary We have screened a large population of M2 seeds ofArabidopsis thaliana for plants which are resistant to exogenously applied indole-acetic acid (IAA). One of the resistant lines identified in this screen carries a dominant mutation which we have namedaxr2. Linkage analysis indicates that theaxr2 gene lies on chromosome 3. Plants carrying theaxr2 mutation are severe dwarfs and display defects in growth orientation of both the shoot and root suggesting that the mutation affects some aspect of gravitropic growth. In addition, the roots ofaxr2 plants lack root hairs. Growth inhibition experiments indicate that the roots ofaxr2 plants are resistant to ethylene and abscisic acid as well as auxin.  相似文献
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细胞分裂素在植物抗逆和延衰中的作用   总被引:40,自引:0,他引:40  
王三根 《植物学通报》2000,17(2):121-126
本文综述了细胞分裂素类物质的种类、分布和在植物抗水分胁迫、低温冷害、病虫害等方面的作用以及在延缓果实、叶片、切花等衰老中的效果,讨论了其生理机制、细胞分裂素与其它植物激素的相互关系,并提出了有关细胞分裂素类物质作用机理中值得深入研究的若干问题,如嘌呤型与苯基脲型细胞分裂素的作用特点,细胞分裂素与生长素、脱落酸的协调作用和拮抗作用细胞分裂素的从头合成途径和tRNA途径等。  相似文献
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Characterization of apelin, the ligand for the APJ receptor   总被引:36,自引:0,他引:36  
The apelin peptide was recently discovered and demonstrated to be the endogenous ligand for the G protein-coupled receptor, APJ. A search of the GenBank databases retrieved a rat expressed sequence tag partially encoding the preproapelin sequence. The GenBank search also revealed a human sequence on chromosome Xq25-26.1, containing the gene encoding preproapelin. We have used the rat sequence to screen a rat brain cDNA library to obtain a cDNA encoding the full-length open reading frame of rat preproapelin. This cDNA encoded a protein of 77 amino acids, sharing an identity of 82% with human preproapelin. Northern and in situ hybridization analyses revealed both human and rat apelin and APJ to be expressed in the brain and periphery. Both sequence and mRNA expression distribution analyses revealed similarities between apelin and angiotensin II, suggesting they that share related physiological roles. A synthetic apelin peptide was injected intravenously into male Wistar rats, resulting in immediate lowering of both systolic and diastolic blood pressure, which persisted for several minutes. Intraperitoneal apelin injections induced an increase in drinking behavior within the first 30 min after injection, with a return to baseline within 1 h.  相似文献
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Aquaporins: water channel proteins of the cell membrane   总被引:34,自引:0,他引:34  
Aquaporins (AQP) are integral membrane proteins that serve as channels in the transfer of water, and in some cases, small solutes across the membrane. They are conserved in bacteria, plants, and animals. Structural analyses of the molecules have revealed the presence of a pore in the center of each aquaporin molecule. In mammalian cells, more than 10 isoforms (AQP0-AQP10) have been identified so far. They are differentially expressed in many types of cells and tissues in the body. AQP0 is abundant in the lens. AQP1 is found in the blood vessels, kidney proximal tubules, eye, and ear. AQP2 is expressed in the kidney collecting ducts, where it shuttles between the intracellular storage sites and the plasma membrane under the control of antidiuretic hormone (ADH). Mutations of AQP2 result in diabetes insipidus. AQP3 is present in the kidney collecting ducts, epidermis, urinary, respiratory, and digestive tracts. AQP3 in organs other than the kidney may be involved in the supply of water to them. AQP4 is present in the brain astrocytes, eye, ear, skeletal muscle, stomach parietal cells, and kidney collecting ducts. AQP5 is in the secretory cells such as salivary, lacrimal, and sweat glands. AQP5 is also expressed in the ear and eye. AQP6 is localized intracellular vesicles in the kidney collecting duct cells. AQP7 is expressed in the adipocytes, testis, and kidney. AQP8 is expressed in the kidney, testis, and liver. AQP9 is present in the liver and leukocytes. AQP10 is expressed in the intestine. The diverse and characteristic distribution of aquaporins in the body suggests their important and specific roles in each organ.  相似文献
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多胺与植物衰老关系研究进展   总被引:33,自引:0,他引:33  
多胺作为生理活性物质与植物衰老关系密切。本文综述了近十年来多胺对衰老的调控作用,从调节细胞膜的理化性质,生物大分子合成作用以及多胺与乙烯的关系等方面阐述了多胺延缓衰老的机制,比较了多胺和影响衰老的植物激素在信号转导过程中的作用。  相似文献
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