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61.
维生素C葡萄糖苷的研究现状及发展前景 总被引:2,自引:0,他引:2
维生素C葡萄糖苷是卫生署公布认可的美白添加剂之一,利用糖基转移酶的特异性转糖基作用进行生物转化合成是目前维生素C葡萄糖苷的唯一生产途径。对维生素c葡萄糖苷的生产方法进行了讨论,着重阐述了其制备(生物转化合成法)、纯化及结晶三大生产工艺的国内外研究现状,指出国内实现维生素C葡萄糖苷工业化生产的发展方向。 相似文献
62.
穿心莲内酯体外抗白念珠菌生物膜作用的初步研究 总被引:6,自引:1,他引:5
目的研究穿心莲内酯对体外白念珠菌生物膜的影响。方法采用XTT减低法评价穿心莲内酯对白念珠菌生物膜及其黏附性的影响;镜下观察该药对白念珠菌生物膜的形态学影响;细胞毒性试验检测该药的毒副作用。结果穿心莲内酯对白念珠菌生物膜的SMIC50、SMIC80分别是250、1000μg/ml;1000μg/ml及100μg/ml时对白念珠菌的早期黏附及菌丝生长有抑制作用;对人细胞毒性较弱。结论穿心莲内酯对体外白念珠菌生物膜有显著的抑制作用。 相似文献
63.
Diah S Zhang GX Nagai Y Zhang W Gang L Kimura S Hamid MR Tamiya T Nishiyama A Hitomi H 《Experimental cell research》2008,314(20):3654-3662
There is accumulating evidence indicating the role of aldosterone in the pathogenesis of hypertension and renal injury. In this study, we investigated the role of the Rho-kinase dependent signaling pathway in aldosterone-induced myofibroblastic transdifferentiation and collagen gene expression in rat mesangial cells (RMCs). Stimulation with aldosterone (1 nmol/L) significantly increased phosphorylation of myosin phosphatase target subunit-1 (MYPT-1), a marker of Rho-kinase activity, with a peak at 20 min in RMCs. Pre-incubation with a selective mineralocorticoid receptor antagonist, eplerenone (10 µmol/L), or a specific Rho-kinase inhibitor, Y27632 (10 µmol/L), attenuated the aldosterone-induced increase in MYPT-1 phosphorylation. Aldosterone also induced hypertrophy in RMCs, accompanied by an increase in actin polymerization and expression of α-smooth muscle actin (α-SMA), a myofibroblastic transdifferentiation marker. Collagen type I, III and IV mRNA levels were also increased with aldosterone stimulation. Pre-treatment with eplerenone or Y27632 prevented the aldosterone-induced cell hypertrophy, actin polymerization, the increase in α-SMA expression and the increases of collagen type I, III, IV mRNA levels in RMCs. These results suggest that aldosterone-induced mesangial cell hypertrophy is associated with cell transformation, leading to an increase in collagen gene expression via the Rho-kinase dependent signaling pathway. 相似文献
64.
Na-Na LIN Hong WANG De-Zhu LI Stephen BLACKMORE 《植物学报(英文版)》2005,47(9):1036-1046
The pollen morphology of 28 species and one variety representing eight genera of the subtribe Mutisiinae Less. sensu Bremer (Compositae) was investigated by scanning electron microscopy (SEM) and light microscopy. The pollen grains are usually radically symmetrical, isopolar, and tricolporate. The shape varies from spheroidal to subprolate in equatorial view and is three-lobed circular in polar view. Based on exine sculpturing observed under SEM, the pollen grains can be divided into three types: (i) type Ⅰ, with macrogranulate sculpture; (ii) type Ⅱ, with a finely granulate sculpture; and (iii) type Ⅲ with spiny sculpture. The palynological data showed that the Macroclinidium Maxim. was remarkably distinguished from those of the other seven genera. The variation of pollen characteristics within the Mutisiinae in Asia is little at species level, but it proves some useful information for studying the relationships among genera and it has an important significance in further understanding the evolutionary history of Mutisiinae. 相似文献
65.
Ectopic Expression of the Pttknl Gene Induces Alterations in the Morphology of the Leaves and Flowers in Petunia hybrida Vilm. 总被引:1,自引:0,他引:1
Xin HU Qing-Feng WU Ya-Hong XIE Hong RU Feng XIE Xin-Yu WANG Chong-Ying WAN 《植物学报(英文版)》2005,47(10):1153-1158
A novel knottedl-like homeobox (knox) gene, Pttknl (Populus tremulaxtremuloides knottedl), isolated from the cambial region of hybrid aspen, was introduced into Petunia hybrida Vilm. using the leafdisc method mediated by Agrobacterium. A series of novel phenotypes was observed in transgenic petunia plants, including the formation of ectopic spikes on the adaxial surface of corollas and small petals on the abaxial surface of corollas, fusion of floral organs, shortening of corolla midribs, the formation of tumor-like knots along the midrib on the abaxial surface and serrated lobs of corolla margins, and alterations in petal color; except for changes in the leaves and plant architecture, RT-PCR showed that the Pttknl gene was expressed in the leaves of different petunia transgenic plants, whereas no signal was detected in wild-type plants. The possible function of Pttknl in leaf and flower development is discussed. 相似文献
66.
Mapping of a Wheat Resistance Gene to Yellow Mosaic Disease by Amplified Fragment Length Polymorphism and Simple Sequence Repeat Markers 总被引:3,自引:0,他引:3
Wei-Hua LIU Huan NIE Zhen-Tian HE Xiu-Lan CHEN Yue-Peng HAN Jin-Rong WANG Xin LI Cheng-Gui HAN Jia-Lin YU 《植物学报(英文版)》2005,47(9):1133-1139
Wheat (Triticum aestivum L.) yellow mosaic virus (WYMV) is transmitted by a fungal vector through soil and causes serious wheat yield losses due to yellow mosaic disease, with yellow-streaked leaves and stunted plants. In the present study, the amplified fragment length polymorphisms (AFLP) and simple sequence repeat (SSR) were used to identify the molecular linkages with the resistance gene against WYMV. Bulked segregant analysis was performed with an F2 population derived from the cross of cultivar Ningmai 9 (resistant) × cultivar Yangmai 10 (susceptible). By screening among the resistant or susceptible parents, the F2 pools and the individuals in the F2 population with 64 combined selective AFLP primers (EcoRI/MseI) or 290 reported SSR primers, a polymorphic DNA segment (approximately 120 bp) was amplified using the primer pair E2/M5, and an SSR marker (approximately 180 bp) was located on wheat chromosome 2A using the primer Xgwm328. Analysis with MAPMAKER/Exp Version 3.0b (Whitehead institute for Biomedical Research, Cambridge, MA, USA) indicated that these two markers were dominantly associated with the resistance gene at distances of 5.4 cM or 17.6 cM, respectively. The resistance gene to WYMV derived from Ningmai 9, is temporarily named YmNM, and was mapped to wheat chromosome 2A. 相似文献
67.
Li YANG Jiang CHEN Catherine C. Y. CHANG Xin-Ying YANG Zhen-Zhen WANG Ta-Yuan CHANG and Bo-Liang LI* State Key Laboratory of Molecular Biology Institute of Biochemistry Cell Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Shanghai China Department of Biochemistry Dartmouth Medical School Hanover NH USA 《Acta biochimica et biophysica Sinica》2004,(4)
Acyl-coenzyme A:cholesterol acyltransferase (ACAT)is an integral membrane protein, which is mainly locatedin rough endoplasmic reticulum (ER), and is responsiblefor catalyzing the intracellular formation of cholesterylester from cholesterol and long-chain fatty acyl-coenzymeA [1,2]. Human ACAT1 cDNA K1 was firstly cloned andfunctionally expressed in 1993 [3]. Further studies withspecific anti-ACAT1 antibody (DM10) illustrated that onemajor 50 kD ACAT1 protein was expressed in various… 相似文献
68.
张更谦 王艳 张艳霞 徐晓莉 邢小平 王英元 贠克明ZHANG Geng-Qian WANG Yan ZHANG Yan-Xia XU Xiao-Li XING Xiao-Ping WANG Ying-Yuan YUN Ke-Ming 《遗传》2004,26(3):0-297
为了应用更多的Y染色体特异性STR基因座以用于法医学和人类遗传学研究,本文用PCR结合PAGE技术检测128例山西汉族无关男性DYS605等位基因分布状况。结果显示:山西地区汉族男性DYS605基因座观察到22,21,20,19,18共5个等位基因,基因频率分别为0.0156;0.1797;0.4531;0.2891;0.0625。等位基因20和19之间的电泳距离在非变性胶上非常接近,要有足够的电泳距离才能区分。测序表明该基因座包括3个串联重复区,其中一个为可变重复区。20例女性DNA未发现扩增产物。Abstract: We study the polymorphism at DYS605 ,a new tetranucleotide Y-STR locus,in a Chinese Han population of Shanxi to meet the need of more genetic markers in forensic practice and genetic analysis. DNA were extracted from 128 unrelated male venous blood, and amplified using GDB primers. PCR products were detected using non-denaturing polyacrylamide gel electrophoresis and silver staining. Five alleles named 22,21,20,19,18 were observed with frequency of 0.0156;0.1797;0.4531;0.2891;0.0625. PCR products were not found in female DNA. Using a long enough gel for a long electrophoresis time is strongly encouraged because the rung between allele 20 and allele19 is smaller than expected. Allele sequences show that the repetitive units of DYS605 were composed with the variant units and non-variant units. 相似文献
69.
王吉振 储明星 王爱国 李宁 傅金恋 谢芳 陈国宏WANG Ji-Zhen CHU Ming-Xing WANG Ai-Guo LI Ning FU Jin-Lian XIE Fang CHEN Guo-Hong 《遗传》2004,26(5):637-647
分析了4个微卫星基因座BM143、OarHH35、OarAE101、BMS2508在7个绵羊群体(小尾寒羊、湖羊、乌珠穆沁羊、萨福克羊、多赛特羊、夏洛来羊、多赛特公羊×小尾寒羊母羊F1代杂种羊)286只绵羊中的遗传多态性。结果表明,这4个微卫星标记在7个绵羊群体中的等位基因数分别为9、11、14和9,其多态信息含量/有效等位基因数/杂合度分别为0.7073/3.7231/0.7314、0.8267/6.4399/0.8447、0.5743/2.5178/0.6028、0.6172/3.0712/0.6744,其中OarHH35的遗传变异最大,OarAE101最小。7个绵羊群体中小尾寒羊的遗传变异最大,湖羊的最小。基于Nei氏DA距离和DS标准遗传距离,采用UPGMA方法构建了系统发生树。该发生树将中国地方品种(小尾寒羊、乌珠穆沁羊、湖羊)和法国的夏洛来羊归为一类,将F1杂种羊、英国品种(萨福克羊和多赛特羊)归为另一类。绵羊微卫星基因分型技术为检查品种(群体)之间的遗传关系提供了一个有用的工具。
Abstract:The genetic polymorphisms of four microsatellite loci BM143,OarHH35,OarAE101,and BMS2508 were analyzed in 286 sheep of seven sheep populations (Small Tail Han sheep, Hu sheep, Ujumqin sheep, Suffolk sheep, Dorset sheep, Charolais sheep, F1 of Dorset♂ × Small Tail Han sheep♀). The numbers of alleles for BM143,OarHH35,OarAE101,and BMS2508 are 9, 11, 14 and 9 in seven sheep populations, respectively. The polymorphism information content/number of effective alleles/ heterozygosity of BM143,OarHH35,OarAE101 and BMS2508 were 0.7073/3.7231/0.7314, 0.8267/6.4399/0.8447,0.5743/2.5178/0.6028,0.6172/3.0712/0.6744
in 286 sheep, respectively. The results revealed the greatest genetic variation at OarHH35 locus and the lowest at OarAE101, the greatest genetic variation in Small Tail Han sheep and the lowest in Hu sheep among seven sheep populations. In the unweighted pair group method with arithmetic mean (UPGMA) dendrograms based on Nei's DA distance and Nei's DS standard genetic distance, the Chinese native breeds (Small Tail Han sheep, Ujumqin sheep, Hu sheep) were grouped together, then with Charolais sheep. The F1 crossbred sheep, and the two British native sheep (Suffolk sheep, Dorset sheep) also clustered together. Microsatellite genotyping in sheep provided a useful tool for examining the genetic relationships among breeds(populations). 相似文献
70.
The complete mitochondrial genomes sequences of Asio flammeus and Asio otus and comparative analysis 总被引:2,自引:0,他引:2
SUN Yi MA Fei XIAO Bing ZHENG Junjie YUAN Xiaodong TANG Minqian WANG Li YU Yefei & Li Qingwei . College of Life Sciences Liaoning Normal University Dalian China . TaKaRa Biotechnology 《中国科学:生命科学英文版》2004,47(6):510-520
Mitochondrial DNA (mtDNA), as a model sys-tem, has been extensively used for molecular phy-logenetic and evolutionary analysis[1]. With the ad-vances in DNA sequencing technology, more andmore researchers prefer to use complete mitochondrialgenome for phylogenetic analysis[2—4]. Since the com-plete sequencing of human mtDNA in 1981 (Andersonet al., 1981)[5], 342 vertebrate mitochondrial genomeshave so far been sequenced. Up to now the completesequences of 29 avian mitochondrial genomes h… 相似文献