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61.
I. Pascual-Castroviejo J. Viaño S. I. Pascual-Pascual V. Martinez 《Neuroradiology》1995,37(8):692-695
We describe a girl with a facial haemangioma, associated with other vascular anomalies: agenesis of the internal carotid artery, cerebral cortical dysplasia and hypoplasia of the cerebral hemisphere on the same side of the angioma. We studied the patient by conventional arteriography, T1- and T2-weighted MRI and magnetic resonance angiography. 相似文献
62.
B. Barbiroli R. Medori H. -J. Tritschler T. Klopstock P. Seibel H. Reichmann S. Iotti R. Lodi P. Zaniol 《Journal of neurology》1995,242(7):472-477
A woman affected by chronic progressive external ophthalmoplegia and muscle mitochondrial DNA deletion was studied by phosphorus magnetic resonance spectroscopy (31P-MRS) prior to and after 1 and 7 months of treatment with oral lipoic acid. Before treatment a decreased phosphocreatine (PCr) content was found in the occipital lobes, accompanied by normal inorganic phosphate (Pi) level and cytosolic pH. Based on these findings, we found a high cytosolic adenosine diphosphate concentration [ADP] and high relative rate of energy metabolism together with a low phosphorylation potential. Muscle MRS showed an abnormal work-energy cost transfer function and a low rate of PCr recovery during the post-exercise period. All of these findings indicated a deficit of mitochondrial function in both brain and muscle. Treatment with 600 mg lipoic acid daily for 1 month resulted in a 55% increase of brain [PCr], 72% increase of phosphorylation potential, and a decrease of calculated [ADP] and rate of energy metabolism. After 7 months of treatment MRS data and mitochondrial function had improved further. Treatment with lipoate also led to a 64% increase in the initial slope of the work-energy cost transfer function in the working calf muscle and worsened the rate of PCr resynthesis during recovery. The patient reported subjective improvement of general conditions and muscle performance after therapy. Our results indicate that treatment with lipoate caused a relevant increase in levels of energy available in brain and skeletal muscle during exercise. 相似文献
63.
Abstract
The neuroimaging findings in an infant with hypernatremic dehydration are presented. Brain parenchymal haemorrhage and extensive
multiple infarcts were present in the acute stage. Follow-up CT showed bilateral, symmetrical changes presumed to indicate
extrapontine myelinolysis in the thalamus and globus pallidus. MRI confirmed sparing of the pons. Only three previous cases
of neuroimaging abnormalities due to hypernatraemia have been described in the radiological literature.
Received: 30 December 1997 Accepted: 6 May 1998 相似文献
64.
CT and MRI in one case of Cryptococcus neoformans infection showed contrast-enhancing parenchymal lesions resembling granulomata or abscesses. After an initial phase without
contrast enhancement, the full extent of the lesions was visible within 2 weeks of presentation. The enhancing masses were
assumed to represent intracerebral cryptococcomas. Despite evidence of massive meningeal infection on cerebrospinal fluid
(CSF) examination, no radiological signs of meningitis, invasion of the Virchow-Robin spaces or ventriculitis could be demonstrated.
With antimycotic treatment the contrast enhancement disappeared and cystic, partly calcified lesions remained. Recurrence
of meningeal infection without radiological correlates was apparent in this stage. In a second case of proven cryptococcus
meningitis, dilation of Virchow-Robin spaces or cysts in the adjacent parenchyma were the main abnormalities on MRI. Enhancing
masses were not detected. These cases may represent two different reactions of the immunocompromised hosts to infection with
C. neoformans: widening of the perivascular spaces as a correlate of the more typical meningeal infection and enhancing parenchymal lesions
as a sign of further invasion from the CSF spaces. Enhancement of cryptococcomas, indicating an inflammatory response in the
surrounding brain, is not typical in patients with impairment of immune function.
Received: 11 March 1998 Accepted: 19 June 1998 相似文献
65.
Chronic spinal subdural haematoma associated with intracranial subdural haematoma: CT and MRI 总被引:3,自引:0,他引:3
Chronic spinal subdural haematoma is a uncommon. We describe the CT and MRI appearances of chronic spinal and intracranial
subdural haematomas following minor trauma. The aetiology, pathogenesis and differential diagnosis are discussed.
Received: 7 January 1998 Accepted: 15 July 1998 相似文献
66.
In this study, thirty-eight patients with a variety of upper abdominal diseases were examined with three-dimensional time-resolved
MR angiography (7 sec/data set). Visualisation of arterial and venous anatomy was excellent in the majority of patients. Moreover,
subtraction images could be calculated and organ perfusion could be assessed. It is concluded that this technique opens new
perspectives for a comprehensive evaluation of vascular and parenchymal disease.
Received: 14 April 1998; Revision received: 23 October 1998; Accepted: 9 November 1998 相似文献
67.
van den Bent MJ de Bruin HG Bos GM Brutel de la Rivière G Sillevis Smitt PA 《Journal of neurology》1999,246(12):1159-1163
Patients with non-Hodgkin’s lymphoma occasionally develop widespread invasion of peripheral nerves by tumor cells or neurolymphomatosis
(NL). Clinically this usually results in asymmetrical, progressive, and painful polyneuropathy. Diagnosis rests on the identification
of tumor cells in peripheral nerves. To avoid false-negative biopsy findings in patients with malignant lymphomatous infiltration
of peripheral nerves it has been recommended to biopsy clinically involved nerves. We present two patients with histologically
confirmed NL in whom sural the nerve biopsy finding was negative despite clinical and neurophysiological evidence of involvement
of the sural nerve a. The clinical features of NL are reviewed. Some patients with neurolyphomatosis have only focal or proximal
involvement of nerves, requiring the biopsy of an affected part of these nerves. Magnetic resonance imaging may be useful
in identifying affected nerves.
Received: 28 January 1999 Received in revised form: 7 July 1999 Accepted: 17 July 1999 相似文献
68.
We report a case of central European tick-borne encephalitis with cervical myelitis presenting clinically as a lower motor
neuron syndrome of the upper limbs with proximal asymmetrical pareses and atrophies. There were no sensory deficits nor signs
of lesions of the spinal pathways or signs of encephalitis or meningitis. The affected motor fibers of the upper limbs were
electrically inexcitable, but sensory findings were normal. Electromyography of the paralyzed muscles revealed pathological
denervation activity without voluntary activation. The initial magnetic resonance imaging (MRI) showed a large hyperdense
lesion in the anterior part of the cervical cord from C3 to T1. Despite the fact that MRI changes disappeared completely within
6 weeks the patient showed only little improvement in the paralyzed muscles after 6 months. To our knowledge, these MRI changes
in patients with tick-borne encephalitis, consistent with an isolated anterior horn lesion, have never been reported previously.
The course may have been aggravated by an initial antibiotic treatment with cephalosporins.
Received: 4 May 1999 Received in revised form: 22 July 1999 Accepted: 26 July 1999 相似文献
69.
Ornithine decarboxylase (ODC) transgenic and alpha-difluoromethyl ornithine (DFMO)-treated rats were exposed to transient middle cerebral occlusion (MCAO) to examine the role of intraischaemic ODC-activity on the evolution of ischaemia-reperfusion damage. Magnetic resonance imaging (MRI) data show that the damage develops slower in ODC transgenic than in DFMO-treated rats, which is not caused by a difference in perfusion. Furthermore, infarct volumes are smaller in the former animals one day later. These data support the idea of endogenous neuroprotective action of ODC. 相似文献
70.
Alan Gevins 《Brain topography》1996,8(3):189-199
Summary The precision of four methods of quantifying neuroelectric signals has been improved by increasing EEG spatial sampling, using up to 124 electrodes, and by accurate anatomical registration of the EEG with Magnetic Resonance Images (MRIs). One such method, equivalent dipole modeling, is a well-known form of source localization which is useful when the generator of the scalp recorded signal approximates a simple dipolar source, as is usually the case with early and mid-latency Evoked Potentials (EPs). Two methods of enhancing spatial detail which benefit from increased spatial sampling include the Laplacian Derivation and the Finite Element Deblurring method. The latter is a new technique which estimates the EP distribution at the superficial cortical surface. The fourth method, Evoked Potential Covariance, characterizes the spatiotemporal relationships among EP segments at different recording sites. This is useful when studying functional neural networks underlying higher cognitive functions. These methods are reviewed and examples of results of their application in recent experiments are presented.Supported by competitive grants from The National Institute of Mental Health, The National Institute of Neurological Diseases and Stroke, The Air Force Office of Scientific Research, The Office of Naval Research, The National Science Foundation NASA and The National Institute on Alcohol Abuse and Alcoholism of the United States Federal Government. Thanks to all members of the EEG Systems Laboratory and SAM Technology, past and present, for their vital contributions to the work presented here.This paper is based on an invited lecture given at the Tenth Anniversary Meeting of The Japanese Society for Brain Electromagnetic Topography held in Fukuoka, Japan in September, 1992. 相似文献