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961.
Demirci B Dadandi MY Paper DH Franz G Başer KH 《Zeitschrift für Naturforschung. C, Journal of biosciences》2003,58(11-12):826-829
Phlomis linearis Boiss. & Bal. of the Lamiaceae family growing in central, east and southeast Anatolia is an endemic species for Turkey. The essential oil obtained from the aerial parts by hydro distillation was subsequently analyzed by GC/MS. The main components of the oil were found as beta-caryophyllene (24.2%), germacrene D (22.3%) and caryophyllene oxide (9.2%), among 49 identified compounds, representing 94.5% of the total essential oil. The overall biological activity of the essential oil (100 microg/pellet) was tested on the chorioallantoic membrane (CAM) of the fertilized hen's egg in order to examine the anti-angiogenic and anti-inflammatory activity. None of the tests showed pronounced activity, toxicity or irritation at the tested concentration. 相似文献
962.
Mittendorf J Kunisch F Matzke M Militzer HC Schmidt A Schönfeld W 《Bioorganic & medicinal chemistry letters》2003,13(3):433-436
A series of novel beta-amino acids has been synthesized and tested for their in vitro antifungal activity against Candida albicans. A steep SAR was observed. beta-Amino acid 21 (BAY 10-8888/PLD-118) revealed the most favourable activity-tolerability profile and was selected for clinical studies as a novel antifungal for the oral treatment of yeast infections. 相似文献
963.
The dominant alopecia phenotypes Bareskin, Rex-denuded, and Reduced Coat 2 are caused by mutations in gasdermin 3 总被引:4,自引:0,他引:4
Runkel F Marquardt A Stoeger C Kochmann E Simon D Kohnke B Korthaus D Wattler F Fuchs H Hrabé de Angelis M Stumm G Nehls M Wattler S Franz T Augustin M 《Genomics》2004,84(5):824-835
Reduced Coat 2 (Rco2) is an ENU-induced mutation affecting hair follicle morphogenesis by an abnormal and protracted catagen. We describe chromosomal mapping and molecular identification of the autosomal dominant Rco2 mutation. The Rco2 critical region on mouse chromosome 11 encompasses the alopecia loci, Bareskin (Bsk), Rex-denuded (Re(den)), Recombination induced mutation 3 (Rim3), and Defolliculated (Dfl). Recently, the gasdermin (Gsdm) gene was described as predominantly expressed in skin and gastric tissues. We provide evidence for a murine-specific gene cluster consisting of Gsdm and two closely related genes which we designate as Gsdm2 and Gsdm3. We show that Gsdm3 reflects a mutation hotspot and that Gsdm3 mutations cause alopecia in Rco2, Re(den), and Bsk mice. We infer a role of Gsdm3 during the catagen to telogen transition at the end of hair follicle morphogenesis and the formation of hair follicle-associated sebaceous glands. 相似文献
964.
Tranquillo JV Franz MR Knollmann BC Henriquez AP Taylor DA Henriquez CS 《American journal of physiology. Heart and circulatory physiology》2004,286(4):H1370-H1381
The extracellular potential at the site of a mechanical deformation has been shown to resemble the underlying transmembrane action potential, providing a minimally invasive way to access membrane dynamics. The biophysical factors underlying the genesis of this signal, however, are still poorly understood. With the use of data from a recent experimental study in a murine heart, a three-dimensional anisotropic bidomain model of the mouse ventricular free wall was developed to study the currents and potentials resulting from the application of a point mechanical load on cardiac tissue. The applied pressure is assumed to open nonspecific pressure-sensitive channels depolarizing the membrane, leading to monophasic currents at the electrode edge that give rise to the monophasic action potential (MAP). The results show that the magnitude and the time course of the MAP are reproduced only for certain combinations of local or global intracellular and interstitial resistances that form a resting tissue length constant that, if applied over the entire domain, is smaller than that required to match the wave speed. The results suggest that the application of pressure not only causes local depolarization but also changes local tissue properties, both of which appear to play a critical role in the genesis of the MAP. 相似文献
965.
Cloning and heterologous expression of hematin-dependent catalase produced by Lactobacillus plantarum CNRZ 1228 总被引:1,自引:0,他引:1
Abriouel H Herrmann A Stärke J Yousif NM Wijaya A Tauscher B Holzapfel W Franz CM 《Applied and environmental microbiology》2004,70(1):603-606
Lactobacillus plantarum CNRZ 1228 exhibited heme-dependent catalase activity under environmental conditions similar to those encountered during sausage fermentation. The 1,455-bp catalase gene (katL) was cloned and encoded a protein of 484 amino acids. Expression of katL in a heterologous host showed that katL encodes a functional catalase. PCR screening of selected strains of lactic acid bacteria for katL indicated the presence of similar genes in other strains of lactobacilli. 相似文献
966.
Amauromyces farinaceous is investigated. The species is a rare corticiaceous Homobasidiomycete recently collected in Taiwan. The unique basidial morphology, cell walls and septal pores of the hyphae are studied by transmission electron microscopy. The study demonstrates the gradual thickening of cell walls in the lower parts of young basidia, leaving only a small asymmetric cytoplasmic channel in mature stages. Systematics of genus Amauromyces are discussed by comparing it with Athelia, Athelopsis, Chaetoderma, Columnocystis, Gloeosoma, Paullicorticium, Sistotremastrum, Trechispora, Tulasnella and Veluticeps. 相似文献
967.
Feil R Hartmann J Luo C Wolfsgruber W Schilling K Feil S Barski JJ Meyer M Konnerth A De Zeeuw CI Hofmann F 《The Journal of cell biology》2003,163(2):295-302
The molecular basis for cerebellar plasticity and motor learning remains controversial. Cerebellar Purkinje cells (PCs) contain a high concentration of cGMP-dependent protein kinase type I (cGKI). To investigate the function of cGKI in long-term depression (LTD) and cerebellar learning, we have generated conditional knockout mice lacking cGKI selectively in PCs. These cGKI mutants had a normal cerebellar morphology and intact synaptic calcium signaling, but strongly reduced LTD. Interestingly, no defects in general behavior and motor performance could be detected in the LTD-deficient mice, but the mutants exhibited an impaired adaptation of the vestibulo-ocular reflex (VOR). These results indicate that cGKI in PCs is dispensable for general motor coordination, but that it is required for cerebellar LTD and specific forms of motor learning, namely the adaptation of the VOR. 相似文献
968.
Atteia A van Lis R Wetterskog D Gutiérrez-Cirlos EB Ongay-Larios L Franzén LG González-Halphen D 《Molecular genetics and genomics : MGG》2003,268(5):637-644
The sequence and organization of the Chlamydomonas reinhardtii genes encoding cytochrome c(1) ( Cyc1) and the Rieske-type iron-sulfur protein ( Isp), two key nucleus-encoded subunits of the mitochondrial cytochrome bc(1) complex, are presented. Southern hybridization analysis indicates that both Cyc1 and Isp are present as single-copy genes in C. reinhardtii. The Cyc1 gene spans 6404 bp and contains six introns, ranging from 178 to 1134 bp in size. The Isp gene spans 1238 bp and contains four smaller introns, ranging in length from 83 to 167 bp. In both genes, the intron/exon junctions follow the GT/AG rule. Internal conserved sequences were identified in only some of the introns in the Cyc1 gene. The levels of expression of Isp and Cyc1 genes are comparable in wild-type C. reinhardtii cells and in a mutant strain carrying a deletion in the mitochondrial gene for cytochrome b (dum-1). Nevertheless, no accumulation of the nucleus-encoded cytochrome c(1) or of core proteins I and II was observed in the membranes of the respiratory mutant. These data show that, in the green alga C. reinhardtii, the subunits of the cytochrome bc(1) complex fail to assemble properly in the absence of cytochrome b. 相似文献
969.
The magnetofection method: using magnetic force to enhance gene delivery 总被引:10,自引:0,他引:10
Plank C Schillinger U Scherer F Bergemann C Rémy JS Krötz F Anton M Lausier J Rosenecker J 《Biological chemistry》2003,384(5):737-747
In order to enhance and target gene delivery we have previously established a novel method, termed magnetofection, which uses magnetic force acting on gene vectors that are associated with magnetic particles. Here we review the benefits, the mechanism and the potential of the method with regard to overcoming physical limitations to gene delivery. Magnetic particle chemistry and physics are discussed, followed by a detailed presentation of vector formulation and optimization work. While magnetofection does not necessarily improve the overall performance of any given standard gene transfer method in vitro, its major potential lies in the extraordinarily rapid and efficient transfection at low vector doses and the possibility of remotely controlled vector targeting in vivo. 相似文献
970.
AP-1 recruitment to VAMP4 is modulated by phosphorylation-dependent binding of PACS-1 总被引:4,自引:0,他引:4 下载免费PDF全文
The R-SNARE VAMP4, which contains a dileucine motif, binds to the AP-1 (adaptor protein-1) subunit μ1a, but not μ1b, or the GGAs (Golgi-associated gamma ear containing ARF binding proteins). Serine 20 and leucines 25,26 are essential for this binding. AP-1 association with VAMP4 is enhanced when serine 30, in an acidic cluster, is phosphorylated by casein kinase 2. This phosphorylation-dependent modulation of AP-1 binding is mediated by PACS-1 (phosphofurin acidic cluster sorting protein). Ablation of both the dileucine motif and serine 30 results in a dramatic mislocalization of VAMP4 in the regulated secretory pathway in AtT20 cells. A dominant-negative PACS-1, which binds acidic clusters but not AP-1, also causes mislocalization of VAMP4. Our data support a model whereby phosphorylation-dependent recruitment of PACS-1 enhances AP-1 association to cargo, and suggest that efficient retrieval depends on the formation of a complex between cargo, such as VAMP4, AP-1 and PACS-1. 相似文献