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991.
Central cholinergic dysfunction has been reported in patients with Parkinson?s disease (PD) and hallucinations by evaluating short latency afferent inhibition (SAI), a transcranial magnetic stimulation protocol which gives the possibility to test an inhibitory cholinergic circuit in the human brain. REM sleep behavior disorder (RBD) was also found to be associated with cognitive impairment in PD patients. The objective of the study was to assess the cholinergic function, as measured by SAI, in PD patients with RBD (PD-RBD) and PD patients without RBD (PD-nRBD). We applied the SAI technique in 10 PD-RBD patients, in 13 PD-nRBD patients and in 15 age-matched normal controls. All PD patients and control subjects also underwent a comprehensive battery of neuropsychological tests. Mean SAI was significantly reduced in PD-RBD patients when compared with PD-nRBD patients and controls. Neuropsychological examination showed mild cognitive impairment in 9 out of the 10 PD-RBD patients, and in 5 out of the 13 PD-nRBD. SAI values correlated positively with neuropsychological tests measuring episodic verbal memory, executive functions, visuoconstructional and visuoperceptual abilities. Similar to that previously reported in the idiopathic form of RBD, SAI abnormalities suggest a cholinergic dysfunction in PD patients who develop cognitive impairment, and present findings indicate that RBD is an important determinant of MCI in PD.  相似文献   
992.

Background

Intracranial atherosclerosis may be the underlying pathology in up to 15% of ischemic strokes, but may account for about 40% of strokes in some populations. After an ischemic event determined by intracranial atherosclerosis, patients have a 12% annual risk of stroke recurrence, mostly during the first year.

Objective

To evaluate procedural safety, clinical outcome and restenosis rate of Wingspan stent placement.

Methods

Twenty-one caucasoid patients were enrolled. Target patients were affected by high-grade, symptomatic, intracranial atherosclerotic lesions, were on antithrombotic therapy and at high stroke risk. All patients were treated with the Wingspan stent system.

Results

Technical success resulted 100%, with all target lesions being reduced to < 50%. No stroke or death were observed at 30.The mean percent of stenosis was reduced from a middle value of 84% to a middle value of 17% after stent placement. Medium follow-up was 19.5 months (range 6–36 months). No stroke or death occurred in any patient. None of the patients presented a <50% stent patency rate at follow-up.

Conclusions

The short-term results and follow up analysis provide evidence demonstrating the safety of the Wingspan system when used in high-risk patient population. Due to concerns regarding long-term stent patency and ischemic events occurrence emerged from clinical trials such as the SAMMPRIS, intracranial angioplasty and stent with the Wingspan system should be considered only for high risk patients in which it may be considered the only viable therapeutic option.  相似文献   
993.
The “applause sign” is a motor perseveration described in focal and neurodegenerative disorders and characterized by fronto-subcortical dysfunction. Most previous formal investigations focused on Parkinson’s disease or progressive supranuclear palsy. We assessed the prevalence of the applause sign in patients affected by Alzheimer’s disease (AD), Lewy body dementia (LBD), corticobasal syndrome (CBS), and posterior cortical atrophy (PCA), with the aim to verify its contribution to the differential diagnosis. We enrolled 20 patients with AD, 20 with LBD, 16 with CBS, and ten with PCA, and 30 healthy controls. The three clap test (TCT) was used to elicit the applause sign, and was scored by raters blinded to the diagnosis. Correlation with motor (extrapyramidal) and cognitive measures was also performed. A maximum 40 % prevalence of a positive applause sign was found in the two parkinsonian syndromes, which could be discriminated from the two cortical groups with a positive predictive value of 82 % and a negative predictive value of 55 %. According to our findings, a diagnosis of LBD or CBS, rather than of AD or PCA, is highly probable in the presence of an abnormal TCP, but cannot be ruled out based on a negative result. No relevant correlates emerged that could clarify the origin and nature of the applause sign.  相似文献   
994.
995.
996.
Tourette syndrome is a neurodevelopmental disorder characterized by multiple tics and is often associated with comorbid behavioral problems. Research with generic instruments in child populations showed that comorbid disorders can have a greater impact on health-related quality of life than tic severity. This study investigated the usefulness of a newly developed disease-specific instrument, the Gilles de la Tourette Syndrome–Quality of Life Scale for Children and Adolescents (GTS-QOL-C&A), in assessing health-related quality of life in young patients with Tourette syndrome with and without behavioral comorbidity. We recruited 75 patients with Tourette syndrome (60 males; age 12.4 ± 3.2 years). All participants were evaluated by a neuropsychiatrist and completed a standardized psychometric battery, including the GTS-QOL-C&A, Child Depression Inventory, and Multidimensional Anxiety Scale for Children. Forty-two patients (56%) fulfilled diagnostic criteria for at least one comorbidity: obsessive-compulsive disorder (n = 25 patients [33.3%]); attention deficit/hyperactivity disorder (n = 6 patients [8%]); both (n = 11 patients [14.7%]). The GTS-QOL-C&A demonstrated usefulness in differentiating “pure” Tourette syndrome from Tourette syndrome “plus” behavioral problems with regard to health-related quality of life scores for the obsessive-compulsive subscale. In addition to focusing on core tic symptoms, the GTS-QOL-C&A showed sensitivity to the impact of behavioral comorbidities on health-related quality of life and can usefully complement existing nonspecific instruments.  相似文献   
997.
Individuals with Down syndrome (DS) exhibit various math difficulties which can be ascribed both to global intelligence level and/or to their atypical cognitive profile. In this light, it is crucial to investigate whether DS display deficits in basic numerical skills. In the present study, individuals with DS and two groups of typically developing (TD) children matched for mental and chronological age completed two delayed match-to-sample tasks in order to evaluate the functioning of visual enumeration skills. Children with DS showed a specific deficit in the discrimination of small numerosities (within the subitizing range) with respect to both mental and chronological age matched TD children. In contrast, the discrimination of larger numerosities, though lower than that of chronological age matched controls, was comparable to that of mental age matched controls. Finally, counting was less fluent but the understanding of cardinality seemed to be preserved in DS. These results suggest a deficit of the object tracking system underlying the parallel individuation of small numerosities and a typical – but developmentally delayed – acuity of the approximate number system for discrimination of larger numerosities.  相似文献   
998.
999.
This article presents a clinical case of bilateral partial edentulism in the posterior mandible with severe horizontal and moderate vertical bone atrophy. A new technique using rapid orthodontics after ridge splitting is presented. The split-crest technique was carried out using piezosurgical instruments in the first molar and second premolar areas to widen the bone crest and open a channel for tooth movement. Immediately after, orthodontic appliances were used to move the first premolars distally and the second molars mesially into the surgical site. The rationale was to facilitate and accelerate orthodontic movement of the teeth, which is otherwise difficult in a cortical knife-edged ridge. The bone defect was filled with the alveolar bone of the adjacent teeth that were moved into the surgically opened path. Adequate bone volume for implant placement was generated in the first premolar area. Implants were then inserted, and the patient was rehabilitated.  相似文献   
1000.
Visible-light-driven CO2 reduction to formate with a system consisting of water-soluble zinc tetraphenylporphyrin tetrasulfonate (ZnTPPS), formate dehydrogenase from Candida boidinii (CbFDH) and methylviologen (MV) in the presence of triethanolamine (TEOA) as an electron donor in an ionic liquid, 1-ethyl-3-methylimidazolium dimethyl phosphate ([EMlm][Me2PO4])/aqueous media was investigated. The catalytic activity of CbFDH for formate oxidation to CO2 and CO2 reduction to formate did not decrease significantly even in [EMlm][Me2PO4]/aqueous media, compared with that in aqueous media. The visible-light-driven MV reduction by the photosensitization of ZnTPPS in [EMlm][Me2PO4]/aqueous media proceeds more efficiently than in the aqueous media system. In the visible-light-driven CO2 reduction to formate system of ZnTPPS, MV and CbFDH with [EMlm][Me2PO4]/aqueous media, moreover, the formate production concentration after 180 min decreased by only 20% as compared with the system in aqueous media.

Visible-light-driven CO2 reduction to formate with water-soluble zinc tetraphenylporphyrin tetrasulfonate, formate dehydrogenase from Candida boidinii and methylviologen in the presence of triethanolamine as an electron donor in an ionic liquid.  相似文献   
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