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81.
Imaging evaluation of posttraumatic renal injuries   总被引:5,自引:0,他引:5  
Computed tomography plays an important role for the evaluation of most patients with suspected renal injury after trauma. Intravenous urography is used for gross assessment of renal function in hemodynamically unstable patients. Renal injuries can be classified into four large groups: (1) minor renal contusion, lacerations, subcapsular hematoma, and small cortical infarcts; (2) major renal lacerations extending to the medulla with or without involvement of the collecting system; (3) catastrophic renal injuries including fragmentation of the kidney and renal pedicle vascular injuries; and (4) ureteropelvic junction injuries. Integration of the imaging findings of renal injury with clinical information is important to developing a treatment plan.  相似文献   
82.
The effects of a hundred-fold difference in virus/cell multiplicity on the interaction of Newcastle disease virus (NDV) with HeLa cells were studied, and various phases of the virus reproductive cycle were related to cellular consequences of infection. At both multiplicities used all cells were infected. The following events occurred 1 to 2 hours earlier in cells which were inoculated with the higher multiplicity: (a) first appearance of newly made virus antigen, and the amount present at any time during the period of rapid increase; (b) onset and time course of production of infective virus; (c) development by infected cells of hemadsorbing ability; (d) onset and time course of inhibition of mitosis; and (e) onset and time course of marked cell damage. Double infection of HeLa cells with NDV and NWS was demonstrated by the fluorescent antibody technique, and was used to show that the establishment of interference against NWS was also dependent upon the multiplicity of NDV. In cells inoculated at each multiplicity, newly made virus antigen appeared at the same time as the first infective virus particles. Infective virus rapidly reached a peak, and then declined. Viral antigen continued to increase for several hours after the decline in infective virus had begun. Thus, only a small fraction of the virus antigen produced was incorporated into new infective particles. The maximal yield of such particles was only 6 to 11 per HeLa cell. Over 95 per cent of new virus was cell-associated, but could be neutralized by treatment with antiserum before disruption of cells. Mitosis occurred in cells which had produced and released infective NDV. Progressive inhibition of mitotic activity in infected cells was correlated with continued production of viral antigen. Marked cytopathic changes developed after mitotic activity had decreased to low levels. The mechanism by which NDV inhibits mitosis in HeLa cells is discussed.  相似文献   
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Children diagnosed with attention-deficit/hyperactivity disorder (ADHD) are at increased risk for substance abuse. Response inhibition is a hallmark of ADHD, yet the combined effects of ADHD and regular substance use on neural networks associated with response inhibition are unknown. Task-based functional Magnetic Resonance Imaging (fMRI) data from young adults with childhood ADHD with (n?=?25) and without (n?=?25) cannabis use ≥ monthly in the past year were compared with a local normative comparison group (LNCG) with (n?=?11) and without (n?=?12) cannabis use. Go/NoGo behavioral and fMRI data were evaluated for main and interaction effects of ADHD diagnosis and cannabis use. ADHD participants made significantly more commission errors on NoGo trials than controls. ADHD participants also had less frontoparietal and frontostriatal activity, independent of cannabis use. No main effects of cannabis use on response inhibition or functional brain activation were observed. An interaction of ADHD diagnosis and cannabis use was found in the right hippocampus and cerebellar vermis, with increased recruitment of these regions in cannabis-using controls during correct response inhibition. ADHD participants had impaired response inhibition combined with less fronto-parietal/striatal activity, regardless of cannabis use history. Cannabis use did not impact behavioral response inhibition. Cannabis use was associated with hippocampal and cerebellar activation, areas rich in cannabinoid receptors, in LNCG but not ADHD participants. This may reflect recruitment of compensatory circuitry in cannabis using controls but not ADHD participants. Future studies targeting hippocampal and cerebellar-dependent function in these groups may provide further insight into how this circuitry is altered by ADHD and cannabis use.  相似文献   
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BACKGROUND: Sarcoidosis is characterised by a T-lymphocytic alveolitis with a typically increased T4/T8 ratio. The diagnostic value of this ratio is under debate. AIM OF THE WORK: We prospectively evaluated the influence of BAL pre-lavage and the impact of bronchial contamination on BAL differential cell count in 108 BAL specimens obtained from patients with histologically confirmed sarcoidosis. METHODS: BAL was performed by instilling 150-300 ml normal saline either in the middle lobe or the lingula. Fifty-one patients (47%) underwent additional pre-lavage with 50 ml normal saline. Bronchial contamination was assessed by semi-quantitative analysis of mucus, ciliated and squamous cells in the untreated BAL recovery. RESULTS: Pre-lavage did neither influence the lavage cellularity nor extend of contamination of the BAL. Content of mucus and ciliated cells, indicating bronchial contamination, showed a high correlation (Kendal's tau=0.61). Presence of either mucus or ciliated cells in the BAL recovery was associated with a significant lower T4/T8 ratio (mucus: 4.9 vs. 8.0, p=0.009; ciliated cells: 4.1 vs. 7.4, p=0.001). Squamous cells in the BAL recovery representing oropharyngeal contamination did not significantly influence the T4/T8 ratio (7.7 vs. 5.6, p=0.10). CONCLUSION: Bronchial contamination of BAL as determined by the presence of mucus and ciliated cells in the recovery decreases the T4/T8 ratio of BAL in sarcoidosis.  相似文献   
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88.

Background  

Health impact assessments (HIA) use information on exposure, baseline mortality/morbidity and exposure-response functions from epidemiological studies in order to quantify the health impacts of existing situations and/or alternative scenarios. The aim of this study was to improve HIA methods for air pollution studies in situations where exposures can be estimated using GIS with high spatial resolution and dispersion modeling approaches.  相似文献   
89.
The current study investigated the role played by conflict monitoring in a lexical-decision task involving competing word representations, using event-related potentials. We extended the multiple read-out model (Grainger and Jacobs, 1996), a connectionist model of word recognition, to quantify conflict by means of Hopfield Energy, which is defined as the sum of the products of all orthographic word node pair activations within the artificial mental lexicon of this model. With increasing conflict levels in nonwords, a late negativity increased in amplitude (400-600 ms) accompanied by activation of the anterior cingulate cortex and the medial frontal gyrus. The simulated conflict predicted the amplitudes associated with this mediofrontal conflict-monitoring network on an item level, and is consistent with the conflict-monitoring theory.  相似文献   
90.
The era of geriatric surgery has arrived with increased global life expectancy. The need to optimize outcomes in this group of patients goes beyond traditional outcomes such as postoperative morbidity and mortality indicators. Recognizing risk factors that impact adverse surgical outcomes such as frailty and sarcopenia, individualizing optimization strategies such as prehabilitation and a multidisciplinary geriatric surgical service have been shown to improve postoperative outcomes and help the older surgical patient regain premorbid function and maintain quality of life. There needs to be a concerted effort to increase awareness of this increasingly important topic in practicing surgeons around the world to meet the challenges of the aging population.  相似文献   
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