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121.
Dominic Bresser Elie Paillard Richard Kloepsch Steffen Krueger Martin Fiedler René Schmitz Dietmar Baither Martin Winter Stefano Passerini 《Liver Transplantation》2013,3(4):513-523
The preparation and electrochemical characterization of a new material consisting of carbon coated ZnFe2O4 nanoparticles is presented. This material, which offers an interesting combination of alloying and conversion mechanisms, is capable of hosting up to nine equivalents of lithium per unit formula, corresponding to an exceptional specific capacity, higher than 1000 mAh g?1. Composite electrodes of such a material, prepared using environmentally friendly sodium carboxymethyl cellulose as binder, showed the highest, ever reported, specific capacity and high rate performance upon long‐term testing. Furthermore, in situ X‐ray diffraction analysis allowed identifying the reduction process occurring upon initial lithiation. 相似文献
122.
Marian Cristian Stan Richard Klöpsch Aiswarya Bhaskar Jie Li Stefano Passerini Martin Winter 《Liver Transplantation》2013,3(2):231-238
Mechanochemical synthesis of Cu3P in the presence of n‐dodecane results in a material with a secondary particle size distribution of 10 μm, secondary particles which consist of homogeneously agglomerated 20 nm primary particles. The electrochemical performance of Cu3P with lithium is influenced by the reaction depth, in other words by the lower potential cut‐off. During the electrochemical reaction, the displacement of copper by lithium from the Cu3P structure until the formation of Li3P and Cu deteriorates the capacity retention. Improved performance was obtained when the charge potential was limited to 0.50 V (vs. Li/Li+) and the formation of the LixCu3‐xP phase (0 ≤ × ≤ 2). In this case, when the potential is limited to 0.5 V, the capacity is stable for more than 50 cycles. Acceptable electrochemical performances in Li‐ion cells within the voltage range 0.50–2.0 V (vs. Li/Li+) were shown when Cu3P was used as an anode and Li1.2(Ni0.13Mn0.54Co0.13)O2 and LiNi0.5Mn1.5O4 as positive electrode materials. 相似文献
123.
Elena Cutrì Paolo Zunino Stefano Morlacchi Claudio Chiastra Francesco Migliavacca 《Biomechanics and modeling in mechanobiology》2013,12(4):657-669
The treatment of coronary bifurcation lesions represents a challenge for the interventional cardiologists due to the lower rate of procedural success and the higher risk of restenosis. The advent of drug-eluting stents (DES) has dramatically reduced restenosis and consequently the request for re-intervention. The aim of the present work is to provide further insight about the effectiveness of DES by means of a computational study that combines virtual stent implantation, fluid dynamics and drug release for different stenting protocols currently used in the treatment of a coronary artery bifurcation. An explicit dynamic finite element model is developed in order to obtain realistic configurations of the implanted devices used to perform fluid dynamics analysis by means of a previously developed finite element method coupling the blood flow and the intramural plasma filtration in rigid arteries. To efficiently model the drug release, a multiscale strategy is adopted, ranging from lumped parameter model accounting for drug release to fully 3-D models for drug transport to the artery. Differences in drug delivery to the artery are evaluated with respect to local drug dosage. This model allowed to compare alternative stenting configurations (namely the Provisional Side Branch, the Culotte and the Inverted Culotte techniques), thus suggesting guidelines in the treatment of coronary bifurcation lesions and addressing clinical issues such as the effectiveness of drug delivery to lesions in the side branch, as well as the influence of incomplete strut apposition and overlapping stents. 相似文献
124.
125.
Qiang Wei Stefano Costanzi Ramachandran Balasubramanian Zhan-Guo Gao Kenneth A. Jacobson 《Purinergic signalling》2013,9(2):271-280
The role of the A2B adenosine receptor (AR) in prostate cell death and growth was studied. The A2B AR gene expression quantified by real-time quantitative RT-PCR and Western blot analysis was the highest among four AR subtypes (A1, A2A, A2B, and A3) in all three commonly used prostate cancer cell lines, PC-3, DU145, and LNCaP. We explored the function of the A2B AR using PC-3 cells as a model. The A2B AR was visualized in PC-3 cells by laser confocal microscopy. The nonselective A2B AR agonist NECA and the selective A2B AR agonist BAY60-6583, but not the A2A AR agonist CGS21680, concentration-dependently induced adenosine 3′,5′-cyclic monophosphate (cyclic AMP) accumulation. NECA diminished lactate dehydrogenase (LDH) release, TNF-α-induced increase of caspase-3 activity, and cycloheximide (CHX)-induced morphological changes typical of apoptosis in PC-3 cells, which were blocked by a selective A2B AR antagonist PSB603. NECA-induced proliferation of PC-3 cells was diminished by siRNA specific for the A2B AR. The selective A2B AR antagonist PSB603 was shown to inhibit cell growth in all three cell lines. Thus, A2B AR blockade inhibits growth of prostate cancer cells, suggesting selective A2B AR antagonists as potential novel therapeutics. 相似文献
126.
Valeria Rimoldi Giulia Soldà Rosanna Asselta Silvia Spena Cristiana Stuani Emanuele Buratti Stefano Duga 《PloS one》2013,8(3)
Most pathological pseudoexon inclusion events originate from single activating mutations, suggesting that many intronic sequences are on the verge of becoming exons. However, the precise mechanisms controlling pseudoexon definition are still largely unexplored. Here, we investigated the cis-acting elements and trans-acting regulatory factors contributing to the regulation of a previously described fibrinogen gamma-chain (FGG) pseudoexon, which is activated by a deep-intronic mutation (IVS6-320A>T). This pseudoexon contains several G-run elements, which may be bound by heterogeneous nuclear ribonucleoproteins (hnRNPs) F and H. To explore the effect of these proteins on FGG pseudoexon inclusion, both silencing and overexpression experiments were performed in eukaryotic cells. While hnRNP H did not significantly affect pseudoexon splicing, hnRNP F promoted pseudoexon inclusion, indicating that these two proteins have only partially redundant functions. To verify the binding of hnRNP F and the possible involvement of other trans-acting splicing modulators, pulldown experiments were performed on the region of the pseudoexon characterized by both a G-run and enrichment for exonic splicing enhancers. This 25-bp-long region strongly binds hnRNP F/H and weakly interacts with Serine/Arginine-rich protein 40, which however was demonstrated to be dispensable for FGG pseudoexon inclusion in overexpression experiments. Deletion analysis, besides confirming the splicing-promoting role of the G-run within this 25-bp region, demonstrated that two additional hnRNP F binding sites might instead function as silencer elements. Taken together, our results indicate a major role of hnRNP F in regulating FGG pseudoexon inclusion, and strengthen the notion that G-runs may function either as splicing enhancers or silencers of the same exon. 相似文献
127.
128.
Stefano Toldo Rachel W. Goehe Marzia Lotrionte Eleonora Mezzaroma Evan T. Sumner Giuseppe G. L. Biondi-Zoccai Ignacio M. Seropian Benjamin W. Van Tassell Francesco Loperfido Giovanni Palazzoni Norbert F. Voelkel Antonio Abbate David A. Gewirtz 《PloS one》2013,8(3)
Purpose
The antineoplastic efficacy of anthracyclines is limited by their cardiac toxicity. In this study, we evaluated the toxicity of doxorubicin, non-pegylated liposomal-delivered doxorubicin, and epirubicin in HL-1 adult cardiomyocytes in culture as well as in the mouse in vivo.Methods
The cardiomyocytes were incubated with the three anthracyclines (1 µM) to assess reactive oxygen generation, DNA damage and apoptotic cell death. CF-1 mice (10/group) received doxorubicin, epirubicin or non-pegylated liposomal-doxorubicin (10 mg/kg) and cardiac function was monitored by Doppler echocardiography to measure left ventricular ejection fraction (LVEF), heart rate (HR) and cardiac output (CO) both prior to and 10 days after drug treatment.Results
In HL-1 cells, non-pegylated liposomal-doxorubicin generated significantly less reactive oxygen species (ROS), as well as less DNA damage and apoptosis activation when compared with doxorubicin and epirubicin. Cultured breast tumor cells showed similar sensitivity to the three anthracyclines. In the healthy mouse, non-pegylated liposomal doxorubicin showed a minimal and non-significant decrease in LVEF with no change in HR or CO, compared to doxorubicin and epirubicin.Conclusion
This study provides evidence for reduced cardiac toxicity of non-pegylated-liposomal doxorubicin characterized by attenuation of ROS generation, DNA damage and apoptosis in comparison to epirubicin and doxorubicin. 相似文献129.
Giovanni Bertolini Alexander A. Tarnutzer Itsaso Olasagasti Elham Khojasteh Konrad P. Weber Christopher J. Bockisch Dominik Straumann Sarah Marti 《PloS one》2013,8(4)
Eccentric gaze in darkness evokes minor centripetal eye drifts in healthy subjects, as cerebellar control sufficiently compensates for the inherent deficiencies of the brainstem gaze-holding network. This behavior is commonly described using a leaky integrator model, which assumes that eye velocity grows linearly with gaze eccentricity. Results from previous studies in patients and healthy subjects suggest caution when this assumption is applied to eye eccentricities larger than 20 degrees. To obtain a detailed characterization of the centripetal gaze-evoked drift, we recorded horizontal eye position in 20 healthy subjects. With their head fixed, they were asked to fixate a flashing dot (50 ms every 2 s)that was quasi-stationary displacing(0.5 deg/s) between ±40 deg horizontally in otherwise complete darkness. Drift velocity was weak at all angles tested. Linearity was assessed by dividing the range of gaze eccentricity in four bins of 20 deg each, and comparing the slopes of a linear function fitted to the horizontal velocity in each bin. The slopes of single subjects for gaze eccentricities of ±0−20 deg were, in median,0.41 times the slopes obtained for gaze eccentricities of ±20−40 deg. By smoothing the individual subjects'' eye velocity as a function of gaze eccentricity, we derived a population of position-velocity curves. We show that a tangent function provides a better fit to the mean of these curves when large eccentricities are considered. This implies that the quasi-linear behavior within the typical ocular motor range is the result of a tuning procedure, which is optimized in the most commonly used range of gaze. We hypothesize that the observed non-linearity at eccentric gaze results from a saturation of the input that each neuron in the integrating network receives from the others. As a consequence, gaze-holding performance declines more rapidly at large eccentricities. 相似文献
130.
Maria Antonella Burza Stefano Romeo Anna Kotronen Per-Arne Svensson Kajsa Sj?holm Jarl S. Torgerson Anna-Karin Lindroos Lars Sj?str?m Lena M. S. Carlsson Markku Peltonen 《PloS one》2013,8(3)