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81.
How do we come to sense that a hand in view belongs to our own body or not? Previous studies have suggested that the integration of vision and somatosensation in the frontoparietal areas plays a critical role in the sense of body ownership (i.e., the multisensory perception of limbs and body parts as our own). However, little is known about how these areas implement the multisensory integration process at the computational level and whether activity predicts illusion elicitation in individual participants on a trial-by-trial basis. To address these questions, we used functional magnetic resonance imaging and a rubber hand illusion-detection task and fitted the registered neural responses to a Bayesian causal inference model of body ownership. Thirty healthy human participants (male and female) performed 12 s trials with varying degrees of asynchronously delivered visual and tactile stimuli of a rubber hand (in view) and a (hidden) real hand. After the 12 s period, participants had to judge whether the rubber hand felt like their own. As hypothesized, activity in the premotor and posterior parietal cortices was related to illusion elicitation at the level of individual participants and trials. Importantly, activity in the posterior parietal cortex fit the predicted probability of illusion emergence of the Bayesian causal inference model based on each participant''s behavioral response profile. Our findings suggest an important role for the posterior parietal cortex in implementing Bayesian causal inference of body ownership and reveal how trial-by-trial variations in neural signatures of multisensory integration relate to the elicitation of the rubber hand illusion.SIGNIFICANCE STATEMENT How does the brain create a coherent perceptual experience of one''s own body based on information from the different senses? We examined how the likelihood of eliciting a classical bodily illusion that depends on vision and touch—the rubber hand illusion—is related to neural activity measured by functional magnetic resonance imaging. We found that trial-by-trial variations in the neural signal in the posterior parietal cortex, a well known center for sensory integration, fitted a statistical function that describes how likely it is that the brain infers that a rubber hand is one''s own given the available visual and tactile evidence. Thus, probabilistic analysis of sensory information in the parietal lobe underlies our unitary sense of bodily self.  相似文献   
82.
Background and aimsAllergic rhinitis (AR) is an inflammatory disorder triggered by an allergic immune response to inhaled allergens. Birch pollen is the major allergenic tree pollen in parts of Europe. ITULAZAX® is a sublingual immunotherapy tablet for the treatment of adults with moderate‐to‐severe AR and/or conjunctivitis induced by pollen from the birch homologous group. The aim was to compare the costs of treating AR with ITULAZAX® versus subcutaneous ALUTARD SQ® Betula verrucosa (ALUTARD SQ®) from a Danish societal perspective.MethodsA cost‐minimization model was developed to capture costs of allergy immunotherapy (AIT), interactions with healthcare professionals (HCPs) in three different care settings (general practice, allergy specialist, and hospital), and indirect costs arising from absenteeism and presenteeism. The cost‐minimization analysis was conducted over a 3‐year time horizon with costs reported in 2021 Danish Kroner (DKK) and Euros (EUR) based on the European Central Bank 365‐day average exchange rate. One‐way sensitivity analyses were performed.ResultsThe base case analysis showed that the total cost of treatment over 3 years was estimated to be DKK 49,117 (EUR 6598) per patient with ALUTARD SQ®, compared with DKK 30,996 (EUR 4164) with ITULAZAX®, reflecting a cost saving of DKK 18,121 (EUR 2434) per patient with ITULAZAX® over 3 years. Over the 3‐year time horizon, costs of AIT were predicted to increase by DKK 17,928 (EUR 2408) with ITULAZAX®, while costs of interactions with HCPs were predicted to decrease by DKK 22,528 (EUR 3027) versus ALUTARD SQ®, more than offsetting the increased cost of ITULAZAX®.ConclusionsGiven the equivalent effectiveness of the two AIT products, and the cost savings with ITULAZAX® versus ALUTARD SQ® from a Danish societal perspective, ITULAZAX® should be considered as a cost‐saving alternative to ALUTARD SQ® for the treatment of birch pollen‐induced moderate‐to‐severe AR in adults.  相似文献   
83.
Behavioral studies found evidence for superior cognitive empathy (CE) in pedophilic men without a history of child sexual offending (P − CSO) compared to pedophilic men with a history of child sexual offending (P + CSO). Functional magnetic resonance imaging (fMRI) studies also point to differences between P − CSO and P + CSO. Neural processing associated with CE has not yet been investigated. Therefore, the present study aimed to explore the neural correlates of CE in subjects with pedophilia with (P + CSO) and without (P − CSO) child sexual offending. 15 P + CSO, 15 P − CSO and 24 teleiophilic male controls (TC) performed a CE task during fMRI. We observed reduced activation in the left precuneus (Pcu) and increased activation in the left anterior cingulate cortex (ACC) in P − CSO compared to P + CSO. P − CSO also showed stronger connectivity between these regions, which might reflect a top-down modulation of the Pcu by the ACC toward an increased self-focused emotional reaction in social situations. There was also evidence for increased right superior temporal gyrus activation in P − CSO that might constitute a potentially compensatory recruitment due to the dampened Pcu activation. These findings provide first evidence for altered neural processing of CE in P − CSO and underline the importance of addressing CE in pedophilia and CSO in order to uncover processes relevant to effective prevention of child sexual abuse.  相似文献   
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Selenium (Se) nanoparticles have been proposed as food supplements. However, the particle formulation may exert unexpected toxicity. The aim was therefore to compare toxicity of low doses of Se nanoparticles and the dissolved, ionized Se species selenite. Female rats were dosed orally for 28?d with either: 0.05, 0.5, or 4?mg Se/kg body weight (bw)/day as 20?nm Se nanoparticles or 0.05 or 0.5?mg Se/kg bw/day as sodium selenite. Male rats were dosed 4?mg Se/kg bw/day as Se nanoparticles. Body weight and clinical appearance were recorded throughout the experiment. At necropsy, blood samples were taken for hematological and clinical chemistry analyses; organ weights were recorded. At the high-dose of Se nanoparticles, overt toxicity occurred and the female animals had to be euthanized prematurely, whereas the male animals were reduced in dose. At all doses of Se nanoparticles and at 0.5?mg Se/kg bw/day as selenite, a lower body weight gain as compared to vehicle occurred. Relative liver weight was increased for both Se formulations at 0.5?mg Se/kg bw/day. Creatinine clearance and urinary pH were affected in some Se dosed groups. There were no effects among dosed groups on brain neurotransmitters or on hematological parameters compared with controls. There were no histological changes in the livers of animals exposed to Se nanoparticles or to selenite. Based on effects on body weight and liver weight, selenium nanoparticles and ionic Se exerted similar toxicity. This suggests that a nanoparticle-specific toxicity of Se did not occur.  相似文献   
89.
Although sexual victimization has been associated with suicidal behaviors, its association with completed suicide has not been examined. We investigated this association among Danish women using longitudinal data and a conservative definition of victimization. This population-based case-control study included 476 suicide cases and 12,010 matched controls. Seven cases (1.5%) and 5 controls (0.04%) experienced sexual victimization that was reported to the police and resulted in a conviction. Sexual victimization was associated with a 14-fold increased rate of suicide, controlling for confounders and matching (95% CI: [3.4, 59]). Completed suicide is an important potential outcome of sexual victimization, warranting further examination.  相似文献   
90.
The physical meaning of Basset force is first studied via polynomial approximation and the Fourier series representation method. After compiling the Basset force into the coupling interface with Visual C, a dynamic mathematical model is set up to describe the upward motion behavior of a single bubble by adopting the CFD-DEM method. Afterwards, the coupling interface with Basset force proposed in this study is verified experimentally and shows very good agreements. The initial velocity, releasing depth, bubble size, density ratio and viscosity ratio are studied qualitatively due to their great importance to Basset force. The ratio of Basset force to the sum of Basset force and drag force and to buoyancy, FBa/(FD+FBa) and |FBa/FB|, are employed to quantify the contribution of Basset force quantitatively. In addition, some instructive outlooks and recommendations on a further development of appropriate and justifiable use of Basset force are highlighted at last.  相似文献   
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