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81.
STUDY OBJECTIVES: REM sleep behavior disorder (RBD) is a common manifestation of Parkinson disease (PD) which is characterized by dream-enacting behaviors, unpleasant dreams, and loss of muscle atonia during REM sleep. Dopaminergic mechanisms are thought to play a role in RBD pathogenesis. To further asses such a role, we have evaluated the effect of pramipexole, a dopamine receptor agonist, on RBD features in PD patients. SETTING: University hospital sleep disorder center. PARTICIPANTS: Eleven PD patients with untreated RBD. interventions: Not applicable. MEASUREMENTS AND RESULTS: In a prospective study, 11 consecutive PD patients with untreated RBD on levodopa monotherapy were placed on pramipexole to further ameliorate their parkinsonism. The effects on RBD were evaluated before and 3 months after stable pramipexole therapy through patient and bed partner interviews and blind assessment of video-polysomnographic measures. Pramipexole improved parkinsonism in all patients. Patients and bed partners reported no significant changes in frequency and severity of the abnormal RBD related motor and vocal sleep behaviors or the frequency of unpleasant dreams. Video-polysomnography analyses showed no differences in RBD related sleep measures including tonic submental electromyographic activity, phasic submental electromyographic activity, percentage of REM sleep time spent with abnormal behaviors, and severity of the abnormal behaviors detected on the videotapes. CONCLUSION: In PD, pramipexole improved parkinsonism but did not modify RBD related symptoms and objective video-polysomnographic abnormalities. This observation suggests that in PD, dopamine mechanisms do not play a central role in the pathogenesis of RBD.  相似文献   
82.
Simian HIV (SHIV) infection of macaques with CXCR4 tropic viruses results in early and profound CD4 T-cell depletion in the first few weeks of infection. Analyzing data from a large study of vaccination and SHIV-89.6P challenge, we observe a strong correlation between peak viral load and the extent of CD4 T-cell depletion in acute infection, consistent with a simple kinetic model of viral infection of CD4 T cells. We have modeled the dynamics of the interaction of virus and CD4 T cells over time to investigate the rate of CD4 T-cell infection and death. This analysis indicates that up to 80% of CD4 T cells are infected at peak viremia and that the proportion of CD4 T cells destroyed is correlated with the peak viral load. The simple relation between viral load and CD4 T-cell depletion allows prediction of the level of viral control required to prevent CD4 T-cell depletion in acute SHIV infection. Whether such a simple relation also holds for HIV or simian immunodeficiency virus infections remains to be determined, particularly in the gut and other anatomic sites in which most early T-cell depletion occurs.  相似文献   
83.
To study dream content in patients with severe obstructive sleep apnea syndrome (OSAS) and its modification with Continuous Positive Airway Pressure (CPAP) therapy. We assessed twenty consecutive patients with severe OSAS and 17 healthy controls. Polysomnograms were recorded at baseline in patients and controls and during the CPAP titration night, 3 months after effective treatment and 2 years later in patients. Subjects were awakened 5-10 min after the beginning of the first and last rapid eye movement (REM) sleep periods and we measured percentage of dream recall, emotional content of the dream, word count, thematic units, sleep architecture and REM density. Dream recall in REM sleep was similar in patients at baseline and controls (51.5% versus 44.4% respectively; P = .421), decreased to 20% and 24.3% the first and third month CPAP nights, and increased to 39% 2 years later (P = 0.004). Violent/highly anxious dreams were only seen in patients at baseline. Word count was higher in patients than in controls. REM density was highest the first CPAP night. Severe OSAS patients recall dreams in REM sleep as often as controls, but their dreams have an increased emotional tone and are longer. Despite an increase in REM density, dream recall decreased the first months of CPAP and recovered 2 years later. Violent/highly anxious dreams disappeared with treatment. A dream recall decrease with CPAP is associated with normalization of sleep in OSAS patients.  相似文献   
84.
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CTLA-4 plays a key role in T cells regulation. We analysed the CTLA-4 +49A/G and −318C/T polymorphisms in 178 cases of type 1 diabetes and their parents (534 individuals) from Santiago, Chile. A significant overall association with T1D (p = 0.028) was observed, possibly due to an overtransmission of the G–T haplotype.  相似文献   
86.
Introduction and objectivesThis is a retrospective Study on patients who underwent septoplasty and septorhinoplasty at Dr. Peset Hospital in Valencia. Surgical procedures are described and results evaluated.Material and methods49 septorhinoplasties and 6 rhinoplasties were aesthetic and functionally evaluated after surgery. Variables such as type of deformity, age, gender, previous surgery and surgical results where described and compared. Fisher exact test was used to find statistic significance between variables.ResultsSeptum remained centred after 91% (45) of septoplasties. There was no statistical significance between type of septal deviation and results. Straight nasal pyramid was obtained after 76% (42) of septorhinoplasties and also in this procedure we did not find statistic significances between deformity and final result. Feminine gender and secondary surgery where predictive factors for worse surgical results.ConclusionSeptopyramidal surgery tries to obtain a good nasal function and aesthetic result. Starting with Cottle′s principles, more specific techniques have been developed to resolve the different deformities.  相似文献   
87.
Lung cancer is a frequent cause of cancer-related deaths in the world. There is no valid screening process and this limits its detection to the late stages, with consequently high mortality rates. Volatile organic compounds (VOC) are chemical compounds (mainly the products of cell catabolism) found as gases in the human breath. Different methods have been developed to analyse VOCs and to compare them in healthy subjects and lung cancer patients. In this review, we summarise the different techniques used to analyse VOC. Many reports have been published with promising results similar to those achieved with accepted screening methods such as mammography. These methods show good perspectives on lung cancer screening. Supported by an unrestricted educational grant from Roche Farma S.A.  相似文献   
88.
This study investigated the estimation of short temporal intervals in Alzheimer's disease (AD). Eight patients with dementia of the Alzheimer type, and eight age-matched controls were evaluated in a time-estimation task. The task consisted in the production of three short empty intervals (5, 10, and 25 s). Results indicated that AD patients show deficits both in the accuracy and precision of time judgments: in the three intervals evaluated, the magnitude of absolute error and the variability in time judgments were significantly greater in AD patients than healthy respondents (p < .01). These findings are discussed taking into account the contribution of attentional processes during the performance of temporal tasks. It is concluded that the estimation of short temporal intervals could be useful as an objective indicator of cognitive decline in AD.  相似文献   
89.
90.
Measurement of cochlear blood flow: intravital fluorescence microscopy   总被引:1,自引:0,他引:1  
A technique is described for directly observing in vivo cochlear microvasculature in the gerbil for physiologic and experimentally induced changes in vessel diameter and blood flow velocity. Measurements are made from computer processed video images of surgically exposed microvessels. These images are obtained using intravital fluorescence microscopy (IFM) with epi-illumination. The Mongolian gerbil is an ideal animal model for circulatory studies of the inner ear. It has a stable heart rate and blood pressure under urethane/alpha-chloralose anesthesia and its cochlea is surgically accessible. A window is created over the feeding artery (anterior inferior cerebellar artery) and over the stria vascularis of the second turn of the cochlea, atraumatically exposing radiating arterioles and strial capillaries. Our system of IFM provides images that are videorecorded, digitally analyzed with a computer image processor, and enhanced according to the type of measurement desired. Velocity measurements are obtained by tracking plasma gaps or single fluorescent labeled red blood cells through successive frames of the videorecorded images. This experimental technique allows us to analyze circulatory responsiveness to a variety of vasoactive drugs administered regionally to the cochlea in concentrations not affecting systemic circulation.  相似文献   
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