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51.

Background  

delayed gastric emptying is detectable in 20–40% of patients with type 1 and type 2 diabetes. The prevalence of symptoms suggestive for diabetic gastroparesis is much lower. The aim of the study was to evaluate the gastric emptying and to correlate the results with dyspeptic symptoms.  相似文献   
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How do visual luminance, shape, motion, and depth bind together in the brain to represent the coherent percept of a 3-D object within hundreds of milliseconds (msec)? We provide evidence from simultaneous magnetoencephalographic (MEG) and electroencephalographic (EEG) data that perception of 3-D objects defined by luminance or motion elicits sequential activity in human visual cortices within 500 msec. Following activation of the primary visual cortex around 100 msec, 3-D objects elicited sequential activity with only little overlap (dynamic 3-D shapes: MT-LO-Temp; stationary 3-D shapes: LO-Temp). A delay of 80 msec, both in MEG/EEG responses and in reaction times (RTs), was found when additional motion information was processed. We also found significant positive correlations between RT, and MEG and EEG responses in the right temporal location. After about 400 msec, long-lasting activity was observed in the parietal cortex and concurrently in previously activated regions. Novel time-frequency analyses indicate that the activity in the lateral occipital (LO) complex is associated with an increase of induced power in the gamma band, a hallmark of binding. The close correspondence of an induced gamma response with concurrent sources located in the LO in both experimental conditions at different points in time ( approximately 200 msec for luminance and approximately 300 msec for dynamic cues) strongly suggests that the LO is the key region for the assembly of object features. The assembly is fed forward to achieve coherent perception of a 3-D object within 500 msec.  相似文献   
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OBJECTIVE: To quantify periarticular subchondral bone changes in a rabbit model of experimental osteoarthritis (OA), and to determine the effects of continuous administration of a clinically relevant dose of glucosamine HCl on subchondral bone changes in this model. METHODS: Anterior cruciate ligament transection (ACLT) was performed on the left femorotibial joints of 16 rabbits to induce OA. Ten rabbits that did not undergo ACLT served as unoperated controls. Eight rabbits that underwent ACLT and 6 control rabbits were treated with 100 mg of glucosamine daily, and the others were given a placebo. The articular cartilage was evaluated macroscopically and graded at the time of necropsy, 8 weeks after ACLT. Bone mineral density (BMD) was measured using dual-energy x-ray absorptiometry on the dissected distal femur and proximal tibia. Subchondral trabecular bone turnover, architecture, and connectivity, as well as subchondral plate thickness and mineralization were studied on the undecalcified tibia sections from each animal. RESULTS: Eight weeks after ACLT, most of the operated joints had various degrees of cartilage damage and fibrillation. Compared with the control group, the ACLT group had significantly increased subchondral bone turnover and lower BMD, bone volume, connectivity, and bone mineralization. The high bone turnover was significantly reduced in glucosamine-treated animals that underwent ACLT. In fact, there were no significant differences between the ACLT/glucosamine group and the control/glucosamine group in most of the bone parameters studied. CONCLUSION: This study shows that subchondral bone turnover, structure, and mineralization are significantly altered in the early stages of experimental OA, and that these changes are attenuated by glucosamine treatment.  相似文献   
55.
Neelapu SS  Gause BL  Harvey L  Lee ST  Frye AR  Horton J  Robb RJ  Popescu MC  Kwak LW 《Blood》2007,109(12):5160-5163
Clinical studies suggest that treatment with vaccines comprised of idiotype protein may be associated with improved clinical outcome in follicular lymphoma patients. The time-consuming process required to generate patient-specific vaccines is a major limitation, however. Here we report results of a pilot clinical trial with a novel autologous, tumor-derived proteoliposome vaccine formulation that could be rapidly produced within a single day. Vaccination was safe, induced autologous tumor-specific type 1 cytokine responses in 5 out of 10 follicular lymphoma patients, and was associated with induction of a sustained complete response in one patient. Other patients had large tumor burdens and progressed after a median duration of 8 months. These results suggest that further testing of this vaccine formulation, particularly in the setting of minimal disease, is warranted. Furthermore, the proteoliposome formulation may provide a model for vaccine development for other human cancers, for which tumor-associated antigens need not be defined.  相似文献   
56.
5-HT6 receptor-like immunoreactivity has been previously found in association with both neuronal dendrites and cilia in the striatum, nucleus accumbens, olfactory tubercle and islands of Calleja of the rat brain. Using immunogold pre-embedding immunocytochemical techniques to investigate the subcellular localization of 5-HT6 receptor-like immunoreactivity in cilia, we showed that immunogold particles were associated with their plasma membrane, and not with microtubules. This membrane localization is consistent with a possible physiological role, which is still unknown, of these receptors.  相似文献   
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The effects of hydroxyzine (8, 16, and 32 mg/kg i.p.), administered either 30 min before exposing rats to a series of inescapable shocks (preventive treatment) or during the subsequent acquisition of a shuttle box avoidance response (curative treatment), wereinvestigated. In these conditions untreated rats, previously exposed to inescapable shocks (“stress” ), show a marked increase in escape failures in the shuttle box when compared with nonshocked control animals (“ learned helplessness” ). Control experiments examined the effects of hydroxyzine on memory (passive avoidance test) and on electric shock sensitivity. Diazepam (2 mg/kg i.p.) was used as a reference compound. Hydroxyzine, when administered before “ stress,” clearly decreased at 8 and 32 mg/kg the number of escape failures observed but was without effect when administered after “stress” during the subsequent shuttle box avoidance learning. Similar results were observed with diazepam. Unlike diazepam, hydroxyzine at 32 mg/kg?1 induced no amnesia in the passive avoidance test, whereas clear amnesia was observed with diazepam. Neither compound altered the rats' sensitivity to shock. These results suggest that hydroxyzine decreases the effects of “ stress” and that these effects cannot be attributed either to impaired memory for the aversive stimulation or to diminished shock sensitivity.  相似文献   
59.
We investigated the regulation of T-type channels by Rho-associated kinase (ROCK). Activation of ROCK via the endogenous ligand lysophosphatidic acid (LPA) reversibly inhibited the peak current amplitudes of rat Ca(v)3.1 and Ca(v)3.3 channels without affecting the voltage dependence of activation or inactivation, whereas Ca(v)3.2 currents showed depolarizing shifts in these parameters. LPA-induced inhibition of Ca(v)3.1 was dependent on intracellular GTP, and was antagonized by treatment with ROCK and RhoA inhibitors, LPA receptor antagonists or GDPssS. Site-directed mutagenesis of the Ca(v)3.1 alpha1 subunit revealed that the ROCK-mediated effects involve two distinct phosphorylation consensus sites in the domain II-III linker. ROCK activation by LPA reduced native T-type currents in Y79 retinoblastoma and in lateral habenular neurons, and upregulated native Ca(v)3.2 current in dorsal root ganglion neurons. Our data suggest that ROCK is an important regulator of T-type calcium channels, with potentially far-reaching implications for multiple cell functions modulated by LPA.  相似文献   
60.
The paper is concerned with the determination of blood permittivity and conductivity in Poiseuille and Couette simple shear flows. The experimental procedure, based on dielectric spectroscopy, evidences the sensitivity of blood electric properties to the applied frequency and local shear rate magnitude. The method evidences the possibility to correlate (for well-defined flow geometry) magnitude of shear rate, and consequently the shear stress level, with spectra permittivity of blood.  相似文献   
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