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91.
采用诱捕法于2010年7月至2011年12月对岳麓山周边地区实蝇的发生情况进行了监测,共获得实蝇类昆虫5种,包括离腹寡毛实蝇属Bactrocera 4种[具条实蝇B.scutellata (Hendel)、南瓜实蝇B.tau (Walker)、瓜实蝇B.cucturbitae (Coquillett)、桔小实蝇B.dorsalis(Hendel)]和合腹寡毛实蝇属Dacus 1种(棍腹实蝇Dacus sp.).其中,具条实蝇发生数量最大,占诱捕总数的76%,从5月到12月有2次数量高峰;其次为瓜实蝇占18%,南瓜实蝇和桔小实蝇数量最少,约各占3%;分析了不同诱剂对各种实蝇的诱捕效果,其中,Me性诱剂仅对桔小实蝇雄虫有引诱效果;Cue性诱剂可引诱具条实蝇、瓜实蝇和南瓜实蝇3种实蝇的雄虫;蛋白诱饵对具条实蝇、瓜实蝇、南瓜实蝇和桔小实蝇的雌、雄虫均有引诱效果.本研究结果可为长沙地区实蝇类害虫的监测和防控提供依据.  相似文献   
92.
为探讨钙(Ca2+)对甜椒幼苗生长的影响,以甜椒品系156为试材,分别喷施清水(对照)、5 mmol·L-1(T5)和10 mmol·L-1Ca Cl2(T10),研究了高温(37℃)强光(1 200μmol·m-2·s-1)胁迫下甜椒幼苗叶片光合作用及叶片中活性氧(ROS)清除酶活性的变化。结果表明,高温强光胁迫条件下,与对照植株相比,外源施钙可维持较高的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)及较低的胞间CO2浓度(Ci)。甜椒幼苗功能叶在高温强光胁迫处理后,T5和T10叶片的1,5-二磷酸核酮糖羧化酶(Rubisco)活性及叶片PSII最大光化学效率(Fv/Fm)较高,表明Ca2+有利于减轻胁迫条件下甜椒幼苗叶片的光抑制现象。另外,高温强光胁迫条件下,植株叶片活性氧清除酶活性和可溶性蛋白含量明显增加,且Ca2+处理(T5和T10)的植株高于对照植株,丙二醛(MDA)含量和相对电导率则明显低于对照,这些结果均表明胁迫条件下外源施钙可以通过提高幼苗叶片ROS清除酶活性和渗透调节物质含量来保护光系统反应中心,从而减轻外界胁迫对植物的伤害。  相似文献   
93.
Wheat end-use quality mainly derives from two interrelated characteristics: the compositions of gluten proteins and grain hardness. The composition of gluten proteins determines dough rheological properties and thus confers the unique viscoelastic property on dough. One group of gluten proteins, high molecular weight glutenin subunits (HMW-GS), plays an important role in dough functional properties. On the other hand, grain hardness, which influences the milling process of flour, is controlled by Puroindoline a (Pina) and Puroindoline b (Pinb) genes. However, little is known about the combined effects of HMW-GS and PINs on dough functional properties. In this study, we crossed a Pina-expressing transgenic line with a 1Ax1-expressing line of durum wheat and screened out lines coexpressing 1Ax1 and Pina or lines expressing either 1Ax1 or Pina. Dough mixing analysis of these lines demonstrated that expression of 1Ax1 improved both dough strength and over-mixing tolerance, while expression of PINA detrimentally affected the dough resistance to extension. In lines coexpressing 1Ax1 and Pina, faster hydration of flour during mixing was observed possibly due to the lower water absorption and damaged starch caused by PINA expression. In addition, expression of 1Ax1 appeared to compensate the detrimental effect of PINA on dough resistance to extension. Consequently, coexpression of 1Ax1 and PINA in durum wheat had combined effects on dough mixing behaviors with a better dough strength and resistance to extension than those from lines expressing either 1Ax1 or Pina. The results in our study suggest that simultaneous modulation of dough strength and grain hardness in durum wheat could significantly improve its breadmaking quality and may not even impair its pastamaking potential. Therefore, coexpression of 1Ax1 and PINA in durum wheat has useful implications for breeding durum wheat with dual functionality (for pasta and bread) and may improve the economic values of durum wheat.  相似文献   
94.
95.
Histone deacetylase 4 (HDAC4) is a member of the HDACs family, its expression is closely related to the cell development. The cell is an independent living entity that undergoes proliferation, differentiation, senescence, apoptosis, and pathology, and each process has a strict and complex regulatory system. With deepening of its research, the expression of HDAC4 is critical in the life process. This review focuses on the posttranslational modification of HDAC4 in cell biology, providing an important target for future disease treatment.  相似文献   
96.
97.
Two new types of stable ternary complexes were formed by mixing chitosan with DOTAP/pDNA lipoplex and DOTAP with chitosan/pDNA polyplex via non-covalent conjugation for the efficient delivery of plasmid DNA. They were characterized by atomic force microscopy, gel retarding, and dynamic light scattering. The DOTAP/CTS/pDNA complexes were in compacted spheroids and irregular lump of larger aggregates in structure, while the short rod- and toroid-like and donut shapes were found in CTS/DOTAP/pDNA complexes. The transfection efficiency of the lipopolyplexes showed higher GFP gene expression than DOTAP/pDNA and CTS/pDNA controls in Hep-2 and Hela cells, and luciferase gene expression 2–3-fold than DOTAP/pDNA control and 70–120-fold than CTS/pDNA control in Hep-2 cells. The intracellular trafficking was examined by confocal laser scanning microscopy. Rapid pDNA delivery to the nucleus enchanced by chitosan was achieved after 4 h transfection.  相似文献   
98.
崔静  徐明芳  章群  李瑶  曾晓舒  李莎 《生物多样性》2022,30(5):21485-144
角木叶鲽(Pleuronichthys cornutus)是东亚沿海重要的鲽形目经济鱼类, 为更好地保护和开发利用其种质资源, 有必要全面了解其遗传背景。本研究测定了中国和日本沿海7个群体200尾角木叶鲽线粒体控制区(CR) 5'端、细胞色素b (Cytb)和NADH脱氢酶第二亚基(ND2)基因序列, 比较不同标记在解析遗传多样性和种群结构上的可行性与有效性, 阐明中日沿海角木叶鲽群体间出现遗传分化的分子机制。CR序列分析发现中日沿海7个角木叶鲽群体遗传多样性表现出较高的单倍型多样性(Hd = 0.9699)和较低的核苷酸多样性(π = 0.0061); 各群体间无显著的遗传分化(FST = -0.0197-0.0184, P > 0.05); 单倍型网络未显示出明显的地理聚群和谱系结构; 分子方差分析(AMOVA)表明变异主要发生在群体内部(> 99.17%)。进一步通过CytbND2基因分别与CR序列对比分析, 结果表明群体遗传多样性均表现为高Hd (0.9683-0.9829)低π (0.0050-0.0063)模式, 仅有ND2基因分析FST值(FST = 0.0302, P < 0.05)显示了中国碣石(GDJS)和日本明石(JAP)群体间显著的低水平遗传分化现象。CRCytbND2的单倍型网络图均无明显的地理聚类和谱系结构, AMOVA分析也显示变异主要来源于群体内(> 98.39%)。种群历史动态分析结果显示, 角木叶鲽可能在第四纪中更新世晚期经历了群体扩张事件, 扩张时间分别为31.93-9.58万年前(CR)、27.53-22.02万年前(Cytb)和26.99-18.75万年前(ND2)。综上所述, 中日沿海的角木叶鲽具有较高遗传多样性, GDJS和JAP群体间存在低度分化; ND2基因比CRCytb序列更适于分析角木叶鲽种群遗传结构, 选择多个遗传标记可有效弥补单一标记分析遗传多样性的局限性; 推测冰期两大独立避难所的形成及GDJS和JAP群体距离相隔较远是其发生遗传分化的主要原因。研究结果为中日沿海角木叶鲽渔业资源的种质保护与可持续利用提供了理论依据。  相似文献   
99.
Plant lipoxygenases (LOXs) are functionally diverse class of dioxygenases involved in multiple physiological processes such as plant growth, biotic and abiotic stress responses, and secondary metabolite accumulation. In this paper, two LOX genes, TcLOX1 and TcLOX2, were cloned from Taxus chinensis cells. Multiple alignment of the deduced amino acid sequences with those of other plants demonstrated the putative LH2/PLAT domain, lipoxygenase iron-binding catalytic domain, lipoxygenase_1 and lipoxygenase_2 signature sequences. Phylogenetic analysis suggested that TcLOX1 and TcLOX2 putative proteins are most probably 9-LOXs, and shared the highest identity with the tea plant CsLOX1 and Picea sitchensis LOX genes, respectively. Semiquantitative RT-PCR analysis showed that TcLOX1 was preferentially expressed in stem and root, while TcLOX2 was preferentially expressed in root. Real-time quantitative PCR analysis showed that a strong upregulation of TcLOX1 was observed in response to methyl jasmonate and abscisic acid (ABA), while TcLOX2 was strongly upregulated by ABA. However, TcLOX1 and TcLOX2 were nearly not responding to salicylic acid. These data suggest both TcLOX1 and TcLOX2 play an important role in T. chinensis, and they are required in different physiological processes involved in different plant signals in vivo.  相似文献   
100.
EB病毒LMP1-CTAR3对NP69细胞增殖和蛋白质表达的影响   总被引:1,自引:0,他引:1  
为了探讨EB病毒潜伏性膜蛋白 1(LMP1)第三个功能活性区域(CTAR3)在鼻咽上皮细胞NP69中的转化作用机制,采用逆病毒感染的方法,将浓缩的逆病毒RV-LMP1和RV-LMP1Δ232~351分别感染鼻咽上皮细胞NP69,建立NP69-LMP1与NP69-LMP1Δ232~351稳定表达细胞系.通过绘制生长曲线、平皿克隆形成试验和软琼脂集落形成试验比较野生型和突变型LMP1对NP69细胞增殖的影响,运用蛋白质组学方法鉴定NP69-LMP1与NP69-LMP1Δ232~351细胞间的差异表达蛋白,选用实时荧光定量RT-PCR与Western blot对其中部分蛋白质点差异表达进行验证.结果发现:a.突变型LMP1Δ232~351促NP69细胞增殖的能力较野生型LMP1明显降低(n=3,P < 0.05);b.鉴定了LMP1-CTAR3在NP69细胞中参与调节的16个蛋白质(表达上调的蛋白质8个,下调的8个).c.实时荧光定量RT-PCR和Western blot证实了部分上述蛋白质的差异表达.以上结果说明,LMP1-CTAR3是其发挥促细胞增殖的重要活性部位,可能通过参与调节G蛋白和异柠檬酸脱氢酶等蛋白质的表达而起作用.  相似文献   
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