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排序方式: 共有625条查询结果,搜索用时 15 毫秒
51.
Antibacterial functionalization of an experimental self-etching primer by inorganic agents: microbiological and biocompatibility evaluations 总被引:1,自引:0,他引:1
Fang M Chai F Chen JH Neut C Jia M Liu Y Zhao SJ Hildebrand HF 《Biomolecular engineering》2007,24(5):483-488
Antibacterial activities have been demonstrated on oral bacteria with inorganic antibacterial agents (ABAs) after their incorporations into an experimental self-etching primer (ESP) before curing. This study was to assess their biocompatibility and antibacterial activity after curing. Six ABAs were incorporated respectively into ESP for treating specimens. After curing, their bactericidal activities on Streptococcus mutans and influences to the early bacterial colonization were assessed by direct contact and viable count. Systemic toxicity in rats after short-term oral exposure and direct contact cytotoxicity with NIH3T3 fibroblasts were tested. Incorporation of ZnOw AT-83, Longbei antibiotic, Antim-AMS2 or IONPURE-H significantly enhanced the antibacterial effect of ESP after curing, even after 1 month aging. Specimens treated by ESP with ZnOw AT-83, Longbei antibiotic or Antim-AMS2 showed slightly less bacterial adhesion than control. Animal experiments revealed neither toxic signs nor significant differences in body weight gain between control and other groups. Cell vitality or proliferation rates were ranged from 76% to 100% with respect to controls. Basic magnesium hypochlorite, ZnOw AT-83 and ZnOw AT-88 were less toxic. Toxicity only observed in areas beneath the specimens and/or in the direct vicinity of the specimen edge. From microbiological and biocompatibility aspects, the tested ABAs can be effectively incorporated in ESP to provide antibacterial activity against S. mutans. ZnOw AT-83 was the most promising one. 相似文献
52.
Nemecek Thomas Antón Assumpció Basset-Mens Claudine Gentil-Sergent Céline Renaud-Gentié Christel Melero Carlos Naviaux Pierre Peña Nancy Roux Philippe Fantke Peter 《The International Journal of Life Cycle Assessment》2022,27(4):527-542
The International Journal of Life Cycle Assessment - Current field emission modelling and toxicity characterisation of pesticides suffer from several shortcomings like mismatches between LCI... 相似文献
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54.
Schuster D Kowalik D Kirchmair J Laggner C Markt P Aebischer-Gumy C Ströhle F Möller G Wolber G Wilckens T Langer T Odermatt A Adamski J 《The Journal of steroid biochemistry and molecular biology》2011,125(1-2):148-161
17β-Hydroxysteroid dehydrogenase type 3 and 5 (17β-HSD3 and 17β-HSD5) catalyze testosterone biosynthesis and thereby constitute therapeutic targets for androgen-related diseases or endocrine-disrupting chemicals. As a fast and efficient tool to identify potential ligands for 17βHSD3/5, ligand- and structure-based pharmacophore models for both enzymes were developed. The models were evaluated first by in silico screening of commercial compound databases and further experimentally validated by enzymatic efficacy tests of selected virtual hits. Among the 35 tested compounds, 11 novel inhibitors with distinct chemical scaffolds, e.g. sulfonamides and triazoles, and with different selectivity properties were discovered. Thereby, we provide several potential starting points for further 17β-HSD3 and 17β-HSD5 inhibitor development. Article from the Special issue on Targeted Inhibitors. 相似文献
55.
Vangestel C Peeters M Mees G Oltenfreiter R Boersma HH Elsinga PH Reutelingsperger C Van Damme N De Spiegeleer B Van de Wiele C 《Molecular imaging》2011,10(5):340-358
In this review, data on noninvasive imaging of apoptosis in oncology are reviewed. Imaging data available are presented in order of occurrence in time of enzymatic and morphologic events occurring during apoptosis. Available studies suggest that various radiopharmaceutical probes bear great potential for apoptosis imaging by means of positron emission tomography and single-photon emission computed tomography (SPECT). However, for several of these probes, thorough toxicologic studies are required before they can be applied in clinical studies. Both preclinical and clinical studies support the notion that 99mTc-hydrazinonicotinamide-annexin A5 and SPECT allow for noninvasive, repetitive, quantitative apoptosis imaging and for assessing tumor response as early as 24 hours following treatment instigation. Bioluminescence imaging and near-infrared fluorescence imaging have shown great potential in small-animal imaging, but their usefulness for in vivo imaging in humans is limited to structures superficially located in the human body. Although preclinical tumor-based data using high-frequency-ultrasonography (US) are promising, whether or not US will become a routinely clinically useful tool in the assessment of therapy response in oncology remains to be proven. The potential of magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) for imaging late apoptotic processes is currently unclear. Neither 31P MRS nor 1H MRS signals seems to be a unique identifier for apoptosis. Although MRI-measured apparent diffusion coefficients are altered in response to therapies that induce apoptosis, they are also altered by nonapoptotic cell death, including necrosis and mitotic catastrophe. In the future, rapid progress in the field of apoptosis imaging in oncology is expected. 相似文献
56.
Upon topical administration, a high penetration rate of antifungal drug into the infected site is desirable to reduce treatment
length and systemic side effects which occur especially after a prolonged peroral administration. Thermogelling formulations
composed of poloxamer 407, medium chain triglycerides, isopropyl alcohol, dimethyl isosorbide, and water for topical application
were developed, and a lipophilic drug terbinafine HCl (TBF) was incorporated. Previously, a remarkable high permeation rate
of a hydrophilic drug 5-aminolevulinic acid from this vehicle was evident compared to different creams from German Pharmacopoeia.
By varying the composition of vehicle constituents, a broad range of consistencies and appearances was obtained. Up to 4%
TBF could be solubilized in the vehicle. TBF fluxes at steady state across human stratum corneum from these formulations were
higher than those from the German Pharmacopoeia Basiscreme Deutscher Arzneimittel Codex and a marketed product at similar
concentration of 1%. TBF fluxes increased along with a higher content of TBF in the formulation. The amount of TBF retained
in stratum corneum was higher compared to those from both standards of comparison (p < 0.01). The thermodynamic activity of TBF in the thermogelling formulation was lower compared to those in other formulations.
Therefore, the nature of the vehicle and its interaction with TBF are suggested to play a significant role in explaining higher
fluxes along with higher TBF content. Differential scanning calorimetry measurements revealed comparable T2 and T3 endothermic
shifts from all examined formulations suggesting equal influences to the skin lipids. 相似文献
57.
Pfefferle S Schöpf J Kögl M Friedel CC Müller MA Carbajo-Lozoya J Stellberger T von Dall'Armi E Herzog P Kallies S Niemeyer D Ditt V Kuri T Züst R Pumpor K Hilgenfeld R Schwarz F Zimmer R Steffen I Weber F Thiel V Herrler G Thiel HJ Schwegmann-Wessels C Pöhlmann S Haas J Drosten C von Brunn A 《PLoS pathogens》2011,7(10):e1002331
Coronaviruses (CoVs) are important human and animal pathogens that induce fatal respiratory, gastrointestinal and neurological disease. The outbreak of the severe acute respiratory syndrome (SARS) in 2002/2003 has demonstrated human vulnerability to (Coronavirus) CoV epidemics. Neither vaccines nor therapeutics are available against human and animal CoVs. Knowledge of host cell proteins that take part in pivotal virus-host interactions could define broad-spectrum antiviral targets. In this study, we used a systems biology approach employing a genome-wide yeast-two hybrid interaction screen to identify immunopilins (PPIA, PPIB, PPIH, PPIG, FKBP1A, FKBP1B) as interaction partners of the CoV non-structural protein 1 (Nsp1). These molecules modulate the Calcineurin/NFAT pathway that plays an important role in immune cell activation. Overexpression of NSP1 and infection with live SARS-CoV strongly increased signalling through the Calcineurin/NFAT pathway and enhanced the induction of interleukin 2, compatible with late-stage immunopathogenicity and long-term cytokine dysregulation as observed in severe SARS cases. Conversely, inhibition of cyclophilins by cyclosporine A (CspA) blocked the replication of CoVs of all genera, including SARS-CoV, human CoV-229E and -NL-63, feline CoV, as well as avian infectious bronchitis virus. Non-immunosuppressive derivatives of CspA might serve as broad-range CoV inhibitors applicable against emerging CoVs as well as ubiquitous pathogens of humans and livestock. 相似文献
58.
Sainlos M Tigaret C Poujol C Olivier NB Bard L Breillat C Thiolon K Choquet D Imperiali B 《Nature chemical biology》2011,7(2):81-91
The interactions of the AMPA receptor (AMPAR) auxiliary subunit Stargazin with PDZ domain-containing scaffold proteins such as PSD-95 are critical for the synaptic stabilization of AMPARs. To investigate these interactions, we have developed biomimetic competing ligands that are assembled from two Stargazin-derived PSD-95/DLG/ZO-1 (PDZ) domain-binding motifs using 'click' chemistry. Characterization of the ligands in vitro and in a cellular FRET-based model revealed an enhanced affinity for the multiple PDZ domains of PSD-95 compared to monovalent peptides. In cultured neurons, the divalent ligands competed with transmembrane AMPAR regulatory protein (TARP) for the intracellular membrane-associated guanylate kinase resulting in increased lateral diffusion and endocytosis of surface AMPARs, while showing strong inhibition of synaptic AMPAR currents. This provides evidence for a model in which the TARP-containing AMPARs are stabilized at the synapse by engaging in multivalent interactions. In light of the prevalence of PDZ domain clusters, these new biomimetic chemical tools could find broad application for acutely perturbing multivalent complexes. 相似文献
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60.
Crystel Bonnet M’hamed Grati Sandrine Marlin Jacqueline Levilliers Jean-Pierre Hardelin Marine Parodi Magali Niasme-Grare Diana Zelenika Marc Délépine Delphine Feldmann Laurence Jonard Aziz El-Amraoui Dominique Weil Bruno Delobel Christophe Vincent Hélène Dollfus Marie-Madeleine Eliot Albert David Catherine Calais Jacqueline Vigneron Bettina Montaut-Verient Dominique Bonneau Jacques Dubin Christel Thauvin Alain Duvillard Christine Francannet Thierry Mom Didier Lacombe Françoise Duriez Valérie Drouin-Garraud Marie-Françoise Thuillier-Obstoy Sabine Sigaudy Anne-Marie Frances Patrick Collignon Georges Challe Rémy Couderc Mark Lathrop José-Alain Sahel Jean Weissenbach Christine Petit Françoise Denoyelle 《Orphanet journal of rare diseases》2011,6(1):1-19