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131.
132.
Objective. Spring ligament insufficiency is associated with chronic posterior tibial tendon dysfunction, and may constitute an indication for surgical repair or reconstruction. This study examines the accuracy of MRI for the diagnosis of insufficiency of the spring ligament. Design and patients. Two experienced musculoskeletal radiologists independently scored the MRI findings in 13 cases of surgically proven spring ligament insufficiency and in 18 control subjects, using a standardized scoring system. Results. Insufficiency of the spring ligament was associated with increased signal heterogeneity on short TE spin echo images, and an increase in the thickness of the medial portion of the ligament. The sensitivity of MRI for the diagnosis of spring ligament insufficiency was 54–77%, while the specificity was 100%. MRI assessment of the plantar portion of the spring ligament was unreliable (kappa=0.33), but the assessment of global ligament integrity was substantially reproducible (kappa=0.76). Conclusion. The medial portion of the spring ligament can be reliably assessed on routine MRI. The findings of spring ligament insufficiency on MRI are only moderately sensitive but highly specific. Received: 12 August 1998 Revision requested: 8 October 1998 Revision received: 21 January 1999 Accepted: 26 January 1999  相似文献   
133.
Attention has been drawn to cardiac sympathetic denervation in Parkinson's disease (PD) based on clinical studies using [123I] metaiodobenzylguanidine scintigraphy; however, the histologic correlates and time course of cardiac sympathetic denervation are poorly understood. To address these issues, we used tyrosine hydroxylase (TH) immunohistochemistry to detect cardiac sympathetic nerve fibers in the epicardium of 4 normal controls, 11 cases with incidental Lewy bodies (iLBs), and 14 cases of PD. Cardiac sympathetic innervation was significantly less in PD than in normal controls and cases with iLBs (P < 0.05). There was also a decrease in TH‐immunoreactive fibers in iLB cases compared to normal controls (P < 0.01). TH‐immunoreactive fibers correlated with the PD stage (r = ?0.75, P < 0.001), as well as with Hoehn & Yahr clinical stage (r = ?0.61, P < 0.001), and disease duration (r = ?0.63, P < 0.001). Immunohistochemistry for α‐synuclein showed neurites in epicardium in PD and iLB cases, but not in normal controls. The density of α‐synuclein neurites correlated with Braak PD stage (r = 0.38, P < 0.05), Hoehn & Yahr clinical stage (r = 0.44, P < 0.05), and disease duration (r = 0.42, P < 0.05). This study demonstrates that cardiac sympathetic degeneration and α‐synuclein pathology is present in presymptomatic phase of PD, and that both increase with disease duration and severity. © 2008 Movement Disorder Society.  相似文献   
134.
BACKGROUND: Prehension is an ideationally simple, cued movement requiring proximal (transport) and distal (manipulation) limb control. Patients with this syndrome of progressive apraxia are unable to perform many activities of daily living that require prehension. There is little known about how this syndrome kinematically disrupts such movements or whether concurrent dementia might play a critical role. OBJECTIVES: Using prehension as a paradigm for an ideationally simple, cued functional movement, we sought to (1) characterize the kinematic features of progressive apraxia in general, and (2) contrast the kinematic differences between apraxic patients with and without dementia. METHODS: Eight patients with the syndrome of progressive apraxia (including five without dementia, one of whom had autopsy-confirmed corticobasal ganglionic degeneration, and three with dementia, one of whom had autopsy-confirmed Alzheimer's disease) were compared with eight age-matched normal control subjects on a prehension task using an Optotrak camera system. RESULTS: Compared with control subjects, apraxic subjects had slowed reaction time, slowed transport and manipulation kinematics, greater lateral deviation from the linear prehension trajectory, greater intermanual asymmetry, motor programming disturbances, and mild transport-manipulation uncoupling. There were minor differences between the apraxia subgroups such as greater intermanual differences and impaired grip aperture velocity in the nondemented group, and overall slower movement in the demented group. CONCLUSIONS: There are major kinematic differences between apraxic and control subjects on a prehension task. The differences between clinical-pathologic subgroups are more subtle, and the movement disorder itself rather than concurrent dementia is the greatest determinant of motor disability.  相似文献   
135.
The spectral ultraviolet (UV) transmission through stockings was measured in field and laboratory based trials using a spectroradiometer. From these spectral UV measurements, the ultraviolet protection factor (UPF) was calculated. The UPF of stockings measured in the field was generally higher than that measured in the laboratory when using a quartz tungsten halogen light as the UV source. The UPF of 50 denier stockings decreased 868% when stretched 30% from their original size. Doctors recommending and patients using high denier stockings for patient photoprotection should be aware of the dramatic decrease in UPF when the stocking is in a stretched position, such as over a human leg.  相似文献   
136.
A spectrum evaluator based on a system of four materials has been applied to the evaluation of actinic ultraviolet exposures to humans. The exposures were evaluated between early morning and near noon in summer and the actinic irradiances calculated ranged from 3 muW cm-2 to 5 muW cm-2. Simultaneously, the broad band irradiances which induced the actinic exposures and/or the biologically effective exposures for any other process may be evaluated with the method. The erythemal exposures ranged from 13 to 23 muW cm-2. The method can be useful both for solar UV studies and research with UV lamps which possess radiation wavelengths shorter than 295 nm where the actinic and erythemal action spectra differ significantly.  相似文献   
137.
A fatal case of glioblastoma multiforme, initially appearing as orofacial pain of unknown cause, is reported. The report of case illustrates the multidisciplinary approach that, at times, is required to diagnose elusive orofacial pain.  相似文献   
138.
139.
Piriformis syndrome (PS) is an unusual cause of sciatica that, because of the lack of strict diagnostic criteria, remains a controversial clinical entity. The diagnosis of PS is still primarily clinical because no diagnostic tests have proven to be definitive. We report the case of a 30-year-old woman, affected by a severe scoliosis, who developed a persistent buttock pain resembling that of PS. The clinical suspicion was confirmed by magnetic resonance imaging (MRI) of the pelvis, which showed an enlargement of the left piriformis muscle with an anterior isplacement of the sciatic nerve. The role of MRI in the diagnosis, clinical definition, and therapeutic approach to PS is discussed.  相似文献   
140.
A 55-year-old man presented with fever, malaise, dysarthria, and intermittent twitching of his right hand. He progressed rapidly to aphasia, intractable myoclonic seizures, and unresponsiveness. Magnetic resonance imaging (MRI) of the head demonstrated multiple nonenhancing areas of signal abnormality involving the cortex of both cerebral hemispheres. Extensive evaluation revealed no infectious cause for his symptoms. Muscle acetylcholine receptor binding and modulating antibodies, striational antibodies, and a neuronal autoantibody specific for collapsin response-mediator protein were detected. An invasive thymoma was discovered and resected. Brain biopsy revealed microglial activation, gliosis, and scant perivascular lymphocytic inflammation. His condition worsened despite treatment with anticonvulsants, intravenous corticosteroids, and antimicrobials. Plasma exchange was performed. The myoclonus stopped; he regained consciousness and gradually improved to the point that he could talk and ambulate with assistance. An MRI revealed regression of the lesions with residual cortical atrophy. This case demonstrates that paraneoplastic encephalitis may occur with thymoma and may extend to cortical regions outside the limbic system.  相似文献   
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