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141.
142.
Photocrosslinked polyacrylic acid hydrogel, made from polyacrylic acid (PAA) modified with 2-hydroxyethyl methacrylate (HEMA),
is a promising candidate adhesive for dermatological patches. In this study, we investigated the further availability of hydrogel
as an adhesive for dermatological patches using a hydrogel containing indomethacin (IDM) as a model anti-inflammatory patch.
From an orthogonal experimental study, we clarified the relationships between formulation factors and characteristics of model
formulation. Formulations with a lower degree of swelling were prepared by increasing the degree of HEMA modification and
the addition of Tween 80. Apparent permeation rate was increased by addition of l-menthol and Tween 80. A tendency for higher HEMA modification to be accompanied by the prolongation of the lag time of IDM
was observed. To obtain an applicable anti-inflammatory patch, we conducted a formulation optimization study using a novel
optimization method, a response-surface method incorporating multivariate spline interpolation (RSM-S). Consequently, a highly
functional anti-inflammatory patch in terms of its adhesive properties and bioavailability was successfully obtained. Since
a wide range of functions can be fully controlled by manipulating the formulation factors, photocrosslinked polyacrylic acid
hydrogel is an attractive candidate adhesive for dermatological patches. 相似文献
143.
Functional analysis of protein disulfide isomerases in blood feeding, viability and oocyte development in Haemaphysalis longicornis ticks 总被引:1,自引:0,他引:1
Liao M Boldbaatar D Gong H Huang P Umemiya R Harnnoi T Zhou J Tanaka T Suzuki H Xuan X Fujisaki K 《Insect biochemistry and molecular biology》2008,38(3):285-295
Three protein disulfide isomerases from Haemaphysalis longicornis ticks (designated as HlPDI-1, HlPDI-2, and HlPDI-3) were previously identified. In order to further analyze their biological functions, the dsRNA of each HlPDI gene and one dsRNA combination of HlPDI-1/HlPDI-3 were separately injected into female ticks. Reduction of gene and protein expression of HlPDIs by RNA interference (RNAi) was demonstrated by real-time PCR, RT-PCR and Western blot analysis. In single dsRNA-injected groups, HlPDI-1 RNAi impacted tick blood feeding and oviposition, HlPDI-2 RNAi impacted tick viability and HlPDI-3 RNAi had no significant impact by itself. However, the injection of a combination of HlPDI-1/HlPDI-3 dsRNA had synergistic effects on tick viability. Furthermore, the midgut and cuticle were severely damaged in HlPDI-2 dsRNA-injected ticks and HlPDI-1/HlPDI-3 dsRNA-injected ticks, respectively, and disruption of HlPDI genes led to a significant reduction of disulfide bond-containing vitellogenin (Vg) expression in ticks. These results indicate that PDIs from H. longicornis are involved in blood feeding, viability and oocyte development, probably by mediating the formation of disulfide bond-containing proteins of the ticks and the formation of basement membrane and cuticle components such as extracellular matrix (ECM). This is the first report on the functional analysis of PDI family molecules as well as the interactions of PDI and other molecules in blood-feeding arthropods. 相似文献
144.
Noriko Ishida Daisuke Irikura Kazuhiro Matsuda Seiji Sato Teruo Sone Michiko Tanaka Kozo Asano 《Current microbiology》2009,58(6):535-540
A gene, mf1, encoding a novel cholinephosphotransferase in glycoglycerophospholipid (GGPL) biosynthesis of Mycoplasma fermentans PG18 was identified by genomic analysis, cloned, and expressed in Escherichia coli. The mf1 gene comprises an open reading frame of 777 bp encoding 258 amino acids. The mf1 gene product, Mf1, has 23% amino acid homology with LicD of Haemophilus influenzae but no homology with genes of other Mycoplasma species in the GenBank database. The reaction product of Mf1 using α-glucopyranosyl-1,2-dipalmitoilglycerol and cytidine
5′-diphosphocholine (CDP-choline) as substrates showed the specific protonated molecule at m/z 896, which corresponded to
GGPL-I as determined by matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF MS). Furthermore,
the product ions of choline, phosphocholine, and hexose-bound phosphocholine were detected by tandem mass spectrometry (MS)
analysis of protonated molecules at m/z 896. These results identified mf1 as a novel cholinephosphotransferase and showed that the phosphocholine transfer step is involved in the GGPL biosynthesis
pathway of M. fermentans. This is the first report of a GGPL biosynthesis enzyme. 相似文献
145.
Mechanism for the definition of elongation and termination by the class II CCA‐adding enzyme
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Yukimatsu Toh Daijiro Takeshita Tomoyuki Numata Shuya Fukai Osamu Nureki Kozo Tomita 《The EMBO journal》2009,28(21):3353-3365
The CCA‐adding enzyme synthesizes the CCA sequence at the 3′ end of tRNA without a nucleic acid template. The crystal structures of class II Thermotoga maritima CCA‐adding enzyme and its complexes with CTP or ATP were determined. The structure‐based replacement of both the catalytic heads and nucleobase‐interacting neck domains of the phylogenetically closely related Aquifex aeolicus A‐adding enzyme by the corresponding domains of the T. maritima CCA‐adding enzyme allowed the A‐adding enzyme to add CCA in vivo and in vitro. However, the replacement of only the catalytic head domain did not allow the A‐adding enzyme to add CCA, and the enzyme exhibited (A, C)‐adding activity. We identified the region in the neck domain that prevents (A, C)‐adding activity and defines the number of nucleotide incorporations and the specificity for correct CCA addition. We also identified the region in the head domain that defines the terminal A addition after CC addition. The results collectively suggest that, in the class II CCA‐adding enzyme, the head and neck domains collaboratively and dynamically define the number of nucleotide additions and the specificity of nucleotide selection. 相似文献
146.
Hajjaj H.M. Abdu-Allah Kozo Watanabe Koji Hayashizaki Chiaki Takaku Taichi Tamanaka Hiromu Takematsu Yasunori Kozutsumi Takeshi Tsubata Hideharu Ishida Makoto Kiso 《Bioorganic & medicinal chemistry letters》2009,19(19):5573-5575
Our previous study revealed that compound 1 (9-(4′-hydroxy-4-biphenyl)acetamido-9-deoxy-Neu5Gcα2-6GalOMP) has the most promising affinity for mCD22. Replacing the subterminal galactose residue of 1 with benzyl or biphenylmethyl as aglycone led to 38- and 20-fold higher potency, respectively. This discovery represents a new direction in inhibitor design suitable for pharmaceutical development. 相似文献
147.
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150.
Katsuhiko Hata Kozo Kaibuchi Shinobu Inagaki Toshihide Yamashita 《The Journal of cell biology》2009,184(5):737-750
Neuronal axons are guided by attractive and repulsive cues in their local environment. Because the repulsive guidance molecule A (RGMa) was originally identified as an axon repellent in the visual system, diverse functions in the developing and adult central nervous system have been ascribed to it. RGMa binding to its receptor neogenin induces RhoA activation, leading to inhibitory/repulsive behavior and collapse of the neuronal growth cone. However, the precise mechanisms that regulate RhoA activation are poorly understood. In this study, we show that Unc5B, a member of the netrin receptor family, interacts with neogenin as a coreceptor for RGMa. Moreover, leukemia-associated guanine nucleotide exchange factor (LARG) associates with Unc5B to transduce the RhoA signal. Focal adhesion kinase (FAK) is involved in RGMa-induced tyrosine phosphorylation of LARG as well as RhoA activation. These findings uncover the molecular basis for diverse functions mediated by RGMa. 相似文献