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891.
It was reported that the growth of Dunaliella salina Teod. cultured in medium containing 1 mol/L NaC1 was almost completely inhibited by the addition of 100 mmol/L KC1. The high K+ (100 mmol/L KC1) treatment also significantly inhibited the photosynthetic rate of D. salina and decreased chlorophyll contents in algae. This study focuses on possible effects of high K+ or alkaline pH on the ultrastructural change of chloroplasts in D. salina. After D. salina was cultured in a medium containing 100 n,anol/L KC1 or in a medium with alkaline pH for 8 to 10 days, dramatic ultrastructural changes occurred in the chloroplasts including thylakoid swelling, volume increase of chloroplast, and significant accumulation of starch grains in chloroplasts. The results are consistent with our previous report indicating that the ultrastmctuml changes in chloroplast under high K + or alkaline pH may lead to an inhibitory effects on photosynthesis and overall growth of D. salina. 相似文献
892.
Genomic constitution of octoploid wheat-wheatgrass amphiploid Zhong 2 was analyzed by chromosome pairing and fluorescence in sim hybridization techniques. The results indicated that the octoploid wheatwheatgrass chromosomes in Zhong 2 were derived from the distant homologous genomes of wheatgrass ( Agropyron intermedium (Host) P.B. = Elytrigia intermedia (Host) Nevski = Thinotopyrum intermedium (Host) Barkworth and Dewey, and thew distant homologous genomes were not from the E geaome of T. elongatum 2x. Zhong 2 contained 12 wheatgrass chromosomes in which a pair of chromosomes was involved in translocation between wheatgrass and wheat chromosomes. 相似文献
893.
EF—Tumt和EF—Tsmt在不同发育阶段小鼠各组织中的表达分析 总被引:1,自引:0,他引:1
线粒体蛋白质翻译延长因子Tu和Ts(mitochondrialelongationfactorTuandTs,EFTumtandEFTsmt)是由核基因编码的两个蛋白质,它们的功能和调控对细胞的生长发育有重要意义。采用EFTumt和EFTsmt重组蛋白分别制备了抗EFTumt和抗EFTsmt特异抗体并以此检测了它们在小鼠不同发育时期心肌、骨骼肌、肝、脑、脾等组织中的表达。蛋白质印迹结果表明EFTumt和EFTsmt在各组织中的表达水平不同、有明显的组织差异性,并都受发育的调节。EFTumt在同一发育时期各组织中的表达及随发育的变化趋势与EFTsmt基本一致。结果提示EFTumt和EFTsmt的表达水平与组织细胞能量代谢水平密切相关,它们不仅在体内以复合体形式发挥作用,其基因表达可能受同一机制的调控。 相似文献
894.
Z6/陕7859胚培养再生植株的细胞遗传学研究与易位系选育 总被引:6,自引:0,他引:6
二体附加系Z6携带抗大麦黄矮病毒病基因,为了将其抗性导入小麦,将Z6与普通小麦陕7859杂交,杂种F1经幼胚培养诱导形成再生植株,对再生植株及后代进行抗性鉴定,农艺性状考察及对SC2部分抗病植株花粉母细胞减数分裂期染色体行为进行了观察。结果表明,(1)SC2不同单株间存在染色体数目,结构的变异。(2)同一再生植株后代的不同单株,染色体数目可能相同,但染色体组成及减数分裂期行为可心不同,致使后代抗性 相似文献
895.
小麦染色体的显微激光分离 总被引:18,自引:0,他引:18
探讨了应用氩离子激光进行植物染色体显微激光切割,分离的可行性,应用该技术对普通小麦的体细胞及特定染色体(1B染色体)实施切割,分离,并且以分离到的单细胞核或单条染色体为模板进行了PCR DNA扩增。该技术比玻璃针切割分离染色体技术,具有操作方便,容易掌握,且可对整个细胞核进行分离等优点,有利于促进染色体显微操作技术的普及应用。同时,探讨了染色体显微操作技术在细胞遗传学及分子生物学研究领域的应用前景 相似文献
896.
Habitat use and selection by Red-crowned Crane Grus japonensis in winter in Yancheng Biosphere Reserve, China 总被引:5,自引:0,他引:5
We report the distribution and habitat selection by the Red-crowned Crane Grus japonensis in winter in the Yancheng Biosphere Reserve, China. Including original wetlands and artificial habitats, six types of habitat are used by the species: saltworks (salinas), fish ponds, reed beds, Wormwood Artemisia halodendron beaches, tidal grasslands and wheat fields. We compared the habitat availability with habitat use in each type. In winter, Red-crowned Crane preferentially used tidal grasslands and fish ponds. Saltworks, Wormwood beaches and wheat fields were avoided. The distribution of Red-crowned Crane in different types of habitat changed with the distribution of freshwater and with human activities. 相似文献
897.
L Scorrano V Petronilli R Colonna F Di Lisa P Bernardi 《The Journal of biological chemistry》1999,274(35):24657-24663
We have investigated the interactions with isolated mitochondria and intact cells of chloromethyltetramethylrosamine (CMTMRos), a probe (Mitotracker Orange) that is increasingly used to monitor the mitochondrial membrane potential (Deltapsi(m)) in situ. CMTMRos binds to isolated mitochondria and undergoes a large fluorescence quenching. Most of the binding is energy-independent and can be substantially reduced by sulfhydryl reagents. A smaller fraction of the probe is able to redistribute across the inner membrane in response to a membrane potential, with further fluorescence quenching. Within minutes, however, this energy-dependent fluorescence quenching spontaneously reverts to the same level obtained by treating mitochondria with the uncoupler carbonylcyanide-p-trifluoromethoxyphenyl hydrazone. We show that this event depends on inhibition of the mitochondrial respiratory chain at complex I and on induction of the permeability transition pore by CMTMRos, with concomitant depolarization, swelling, and release of cytochrome c. After staining cells with CMTMRos, depolarization of mitochondria in situ with protonophores is accompanied by changes of CMTMRos fluorescence that range between small and undetectable, depending on the probe concentration. A lasting decrease of cellular CMTMRos fluorescence associated with mitochondria only results from treatment with thiol reagents, suggesting that CMTMRos binding to mitochondria in living cells largely occurs at SH groups via the probe chloromethyl moiety irrespective of the magnitude of Deltapsi(m). Induction of the permeability transition precludes the use of CMTMRos as a reliable probe of Deltapsi(m) in situ and demands a reassessment of the conclusion that cytochrome c release can occur without membrane depolarization and/or onset of the permeability transition. 相似文献
898.
始叶螨属(Eotetranychus Oudemans,1931)是叶螨科中较大的一个属。自1931年建属以来,种数不断迅速增加,目前已知种数达150余种,仅次于叶小爪属(OligotetrangchusBerlese)。国内自60年代开始研究,迄今已发现30种。作者在研究华东园林叶螨时,发现了该属叶螨四新种,兹记述如下。模式标本保存于上海农学院植保系。文中测量单位 相似文献
899.
本实验对家蚕Bombyx mori五龄健康的雌雄幼虫、氟中毒的雌幼虫、细胞质多角体病毒(CPV)感染的雄幼虫血淋巴内的烟酸、烟酰胺、吡哆辛(VB6)、硫胺素(VB1)及核黄素(VB2)含量,采用离子对反相色谱法进行了定量测定.在五龄幼虫发育阶段,血淋巴内每种维生素含量均是雌蚕高于雄蚕,健康者高于病态者,且病蚕含维生素的量持续下降;烟酸和烟酰胺浓度一直减少,可能是部分烟酸、烟酰胺在酶作用下与某些蛋白质结合,部分烟酸、烟酰胺形成NADP酶的缘故;VB6、VB1和VB2浓度增加,是幼虫大量摄食、贮存能量和营养,供日后生命循环需要的结果. 相似文献
900.
蚤类在宿主体表的分布及温度和蚤数的关系 总被引:3,自引:0,他引:3
本文研究了方形黄鼠蚤松江亚种Citellophilus tesquorum sungaris和二齿新蚤Neopsylla bidentatiformis在小白鼠体表的分布及环境温度和体表蚤数的关系.结果证明,在各种温度下,鼠背部蚤数均多于腹部.5℃时,鼠前部蚤数多于后部;10—20℃时,前部与后部蚤数相近;25—40℃时,后部蚤数多于前部.鼠后背部蚤数随温度升高而增多,前腹部蚤数随温度升高而减少;温度越高二者之差越大,说明温度越高蚤越向后背部集中.鼠体蚤数较少时,背部与腹部,前部与后部,蚤数差别明显;鼠体蚤数过多时,各部位蚤数无大差别. 相似文献