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1.
P-glycoprotein (P-gp) is an ATP-dependent efflux pump that has a marked impact on the absorption, distribution, and excretion of therapeutic drugs. As P-gp inhibition can result in drug–drug interactions and altered drug bioavailability, identifying molecular properties that are linked to inhibition is of great interest in drug development. In this study, we combined chemical synthesis, in vitro testing, quantitative structure–activity relationship analysis, and docking studies to investigate the role of hydrogen bond (H-bond) donor/acceptor properties in transporter–ligand interaction. In a previous work, it has been shown that propafenone analogs with a 4-hydroxy-4-piperidine moiety exhibit a generally 10-fold higher P-gp inhibitory activity than expected based on their lipophilicity. Here, we specifically expanded the data set by introducing substituents at position 4 of the 4-phenylpiperidine moiety to assess the importance of H-bond donor/acceptor features in this region. The results suggest that indeed an H-bond acceptor, such as hydroxy and methoxy, increases the affinity by forming a H-bond with Tyr310.  相似文献   
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The cochlea of our auditory system is an intricate structure deeply embedded in the temporal bone. Compared with other sensory organs such as the eye, the cochlea has remained poorly accessible for investigation, for example, by imaging. This limitation also concerns the further development of technology for restoring hearing in the case of cochlear dysfunction, which requires quantitative information on spatial dimensions and the sensorineural status of the cochlea. Here, we employed X-ray phase-contrast tomography and light-sheet fluorescence microscopy and their combination for multiscale and multimodal imaging of cochlear morphology in species that serve as established animal models for auditory research. We provide a systematic reference for morphological parameters relevant for cochlear implant development for rodent and nonhuman primate models. We simulate the spread of light from the emitters of the optical implants within the reconstructed nonhuman primate cochlea, which indicates a spatially narrow optogenetic excitation of spiral ganglion neurons.

In the case of profound sensorineural hearing impairment, cochlear implants (CIs) partially restore hearing by providing auditory information to the brain via electrical stimulation of the spiral ganglion neurons (SGNs). CIs enable speech understanding in the majority of the ∼700,000 users worldwide. However, current clinical CIs are limited by their wide current spread (1) resulting in poor coding of spectral information (2). Recently, cochlear optogenetics was proposed for stimulating the auditory nerve by light (310). As light can be better confined in space, the spread of excitation in the cochlea is lower (3, 911) and, hence, future optical CIs (oCIs) promise improved speech comprehension—especially in noisy background—as well as greater music appreciation.For the technical development of oCIs toward a future medical device, major efforts are currently being undertaken to devise multichannel optical stimulators for the cochlea (10, 1217). As is the case for the electrodes of current CIs, future oCIs will place multiple stimulation channels, here microscale emitters, along the tonotopic axis of the cochlea. Further development of the oCIs requires precise estimates of parameters such as scala tympani size, optimal probe stiffness, and bending radius. Moreover, cochlear optogenetics employs gene transfer to the SGNs for which adeno-associated viruses (AAVs) seem promising candidate vectors (35, 8). AAV delivery has used injection of virus suspension via the round window (4, 8) or directly into Rosenthal’s canal (5, 9, 10). Therefore, the volumes of Rosenthal’s canal and the scalae tympani, vestibuli and media needed to be evaluated in order to estimate the required virus load for injection. Finally, the sensorineural status of the cochlea is highly relevant for future gene therapy and CI stimulation, and hence, quantitative imaging of sensory cells and neurons is an important objective.Here, we employed multiscale X-ray phase-contrast tomography (XPCT) and light-sheet fluorescence microscopy (LSFM) and provide an analysis of cochlear morphology for mice, rats, gerbils, guinea pigs, and marmosets. Each of these animal models offers unique advantages for auditory research. The mouse is readily available for genetic manipulation (e.g., ref. 18). Channelrhodopsin-expressing transgenic lines are available also for rats (19, 20) that offer a larger cochlea and can carry heavier implants than mice (2124). Similarly, gerbils and guinea pigs are established rodent models for auditory research with larger-sized cochleae. Moreover, gerbils, which have low-frequency hearing more similar to humans, have already been employed for cochlear optogenetics (5, 9, 10, 24). Finally, we analyzed the cochlea of the common marmoset, as an established nonhuman primate model for auditory research (e.g., refs. 25, 26). Marmosets possess a rich vocalization repertoire and share a pitch perception mechanism with humans (27). Therefore, we compared cochlear insertion of newly designed oCIs with electrical cochlear implants (eCI) and modeled the optical spread of excitation in the marmoset cochlea.  相似文献   
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Ligament disruptions at the craniovertebral junction are typically associated with atlantoaxial rotatory dislocation during upper cervical spine injuries and require external orthoses or surgical stabilization. Only in few patients isolated ruptures of the alar ligament have been reported. Here we present a further case, in which the diagnosis was initially obscured by a misleading clinical symptomatology but finally established six month following the trauma, demonstrating the value of contrast-enhanced high resolution 3 Tesla magnetic resonance imaging in identifying this particular lesion.  相似文献   
5.
BackgroundTreatment decisions in routine clinical practice are based on reports of clinical trials, which represent highly selected populations. Limited studies reported real-world evidences representing routine clinical practices in patients with renal-cell carcinoma (RCC) in Europe. The aim of this retrospective, noninterventional chart review was to collect data on the treatment landscape for patients with advanced/metastatic RCC in routine clinical practice in a broader patient population in Austria.Patients and MethodsPatients with advanced/metastatic RCC receiving systemic treatment between June 2010 and June 2016 across 12 centers in Austria were included. Parameters were entered into an electronic case report form from the participating sites via the application Hermesoft electronic data capture system. Progression-free survival (PFS) and overall survival (OS) were the 2 primary end points.ResultsThe median PFS and OS were 12 months and 44 months, respectively (first-line PFS was 14 months for pazopanib and 13 months for sunitinib; first-line OS was 44 months for pazopanib and 48 months for sunitinib). Factors influencing the OS were sex, with female patients at a significantly higher risk than male patients (hazard ratio = 1.719), Eastern Cooperative Oncology Group performance status > 0 increased the risk twice (hazard ratio = 2.048), and number of metastases > 3 before the first line doubled the risk compared to metastases (hazard ratio = 2.064).ConclusionOS in this retrospective chart review was considerably longer than the previous reports in real-world patients, underlining the benefit of current RCC treatment options in routine clinical practice.  相似文献   
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The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research.  相似文献   
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