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11.
Howard A. Bern Susan Goldstein Richard S. Nishioka Robert Gunther 《Acta zoologica》1982,63(3):177-180
A seasonal study of urotensin II content of the urophysis of the goby, Gillichthys mirabilis. was conducted from March 1979 to June 1980 in relation to certain internal and environmental changes. Urotensin II content (lowest in November–January) is inversely correlated with female gonadosomatic index and to some extent with rainfall (and hence dilution of the environmental salinity). In addition, there appears to be a direct correlation between UII content and daylength and temperature. 相似文献
12.
An improved approach for transformation of plant cells by microinjection: molecular and genetic analysis 总被引:4,自引:0,他引:4
Martin Schnorf Gabriele Neuhaus-Url Alessandro Galli Shigeru Iida Ingo Potrykus Gunther Neuhaus 《Transgenic research》1991,1(1):23-30
A new culture method for the injection of tobacco mesophyll protoplasts has been established. The protoplasts are embedded
in a thin layer of alginate and are nourished from the medium in the underlying basislayer. In the alginate layer the protoplasts
regenerate to calli at a frequency of up to 80%. Embedded protoplasts can be selected either with 50 mg l−1 kanamycin or 5 mg l−1 paromomycin. Single resistant cells can be recovered from about 10 000 sensitive cells in one alginate layer. Injection of
theneo gene (coding for neomycin phosphotransferase II) into protoplast derived single cells in the alginate layer results in kanamycin
resistant colonies that can be regenerated to mature plants. These plants express the neomycin phosphotransferase as shown
by enzyme activity assay. The integration of the transgene into the plant genome could be proved by Southern hybridization
to high molecular weight DNA. With this culture method 100 cells can be injected per hour. Transformation frequencies range
from 2 to 20%. In crossing experiments, it was shown that the foreign gene is transmitted to the next generation in a Mendelian
fashion. 相似文献
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Gunther Ott Lubos Arnold Jiri Smrt Michal Sobkowski Stefan Limmer Hans-Peter Hofmann 《Nucleosides, nucleotides & nucleic acids》2013,32(5):1069-1085
Abstract Dimethylaminomethylene was applied as the protecting group for the exocyclic amino groups of adenosine and guanosine in the automated chemical synthesis of oligoribonucleotides on a polymer bound support. The dimethyl-aminomethylene protecting group can be removed at room temperature under conditions where the concomitant loss of the 2′-protection group can be excluded. The transformation of 2′-O-(t-butyldimethylsilyl)-5′-O-(4,4′-dimethoxytrityl) protected nucleosides to 3′-H-phosphonates yields synthons, well suited for the automated chemical synthesis of oligoribonucleotides. Using these H-phosphonate monomers, a coupling time of two minute: is sufficient to obtain average coupling yields of more than 98 %. Synthesized RNA is recognized as a substrate in an enzymatic reaction, forms the expected secondary structures and is suitable for NMR structural investigations. 相似文献
19.
Ivana Sreckovic Ruth Birner-Gruenberger Britta Obrist Tatjana Stojakovic Hubert Scharnagl Michael Holzer Monika Scholler Sonia Philipose Gunther Marsche Uwe Lang Gernot Desoye Christian Wadsack 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2013,1831(4):737-746
In human high-density lipoprotein (HDL) represents the major cholesterol carrying lipoprotein class in cord blood, while cholesterol is mainly carried by low-density lipoprotein in maternal serum. Additionally, to carrying cholesterol, HDL also associates with a range of proteins as cargo. We tested the hypothesis that fetal HDL carries proteins qualitatively and quantitatively different from maternal HDL. These differences then contribute to distinct HDL functionality in both circulations. Shotgun proteomics and biochemical analyses were used to assess composition/function of fetal and maternal HDL isolated from uncomplicated human pregnancies at term of gestation. The pattern of analyzed proteins that were statistically elevated in fetal HDL (apoE, proteins involved in coagulation, transport processes) suggests a particle characteristic for the light HDL2 sub-fraction. In contrast, proteins that were enriched in maternal HDL (apoL, apoF, PON1, apoD, apoCs) have been described almost exclusively in the dense HDL3 fraction and relevant to its anti-oxidative function and role in innate immunity. Strikingly, PON1 mass and activity were 5-fold lower (p < 0.01) in the fetus, which was accompanied by attenuation of anti-oxidant capacity of fetal HDL. Despite almost equal quantity of CETP in maternal and fetal HDL, its enzymatic activity was 55% lower (p < 0.001) in the fetal circulation, whereas LCAT activity was not altered. These findings indicate that maternally derived HDL differs from fetal HDL with respect to its proteome, size and function. Absence of apoA-1, apoL and PON1 on fetal HDL is associated with decreased anti-oxidative properties together with deficiency in innate immunity collectively indicating distinct HDLs in fetuses. 相似文献
20.
Christoph Coch Christian Lück Anna Schwickart Bastian Putschli Marcel Renn Tobias H?ller Winfried Barchet Gunther Hartmann Martin Schlee 《PloS one》2013,8(8)
Therapeutic oligonucleotides including siRNA and immunostimulatory ligands of Toll-like receptors (TLR) or RIG-I like helicases (RLH) are a promising novel class of drugs. They are in clinical development for a broad spectrum of applications, e.g. as adjuvants in vaccines and for the immunotherapy of cancer. Species-specific immune activation leading to cytokine release is characteristic for therapeutic oligonucleotides either as an unwanted side effect or intended pharmacology. Reliable in vitro tests designed for therapeutic oligonucleotides are therefore urgently needed in order to predict clinical efficacy and to prevent unexpected harmful effects in clinical development. To serve this purpose, we here established a human whole blood assay (WBA) that is fast and easy to perform. Its response to synthetic TLR ligands (R848: TLR7/8, LPS: TLR4) was on a comparable threshold to the more time consuming peripheral blood mononuclear cell (PBMC) based assay. By contrast, the type I IFN profile provoked by intravenous CpG-DNA (TLR9 ligand) in humans in vivo was more precisely replicated in the WBA than in stimulated PBMC. Since Heparin and EDTA, but not Hirudin, displaced oligonucleotides from their delivery agent, only Hirudin qualified as the anticoagulant to be used in the WBA. The Hirudin WBA exhibited a similar capacity as the PBMC assay to distinguish between TLR7-activating and modified non-stimulatory siRNA sequences. RNA-based immunoactivating TLR7/8- and RIG-I-ligands induced substantial amounts of IFN-α in the Hirudin-WBA dependent on delivery agent used. In conclusion, we present a human Hirudin WBA to determine therapeutic oligonucleotide-induced cytokine release during preclinical development that can readily be performed and offers a close reflection of human cytokine response in vivo. 相似文献