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121.
We present a rare case of a 27-year-old man sustaining a bilateral fracture dislocation of the sacroiliac joints without
disruption of the anterior pelvis, following a fall from a height. Reconstructed images in the coronal plane and three-dimensional
CT images were invaluable in the diagnosis and assessment of this injury. 相似文献
122.
Neuroradiological features of intracranial and intraorbital meningeal haemangiopericytomas 总被引:9,自引:1,他引:8
J. Ruscalleda M. Feliciani A. Avila E. Castañer E. Guardia M. de Juan 《Neuroradiology》1994,36(6):440-445
The neuroradiological features of six intracranial and one intraorbital haemangiopericytomas (HP) are reviewed. CT was performed before and after IV contrast medium in 5 patients. In 2 patients MRI was performed before and after contrast medium; in another, only unenhanced images were obtained. Five patients were studied by selective external and internal carotid artery angiography. Women constituted 5 of the 7 patients, and the mean age was 50.5 years, thus the sex and age distribution did not differ from that of typical meningiomas. Contrary to previous reports, calcification was present in two of the intracranial HP, and bone erosion was clearly seen in one intracranial HP and the orbital lesion. On MRI the tumours showed no differences from angioblastic meningiomas. All 6 intracranial HP were aggressive; all recurred following treatment and extracerebral metastasis occurred in one case. 相似文献
123.
Richard C. Semelka Suvipapun Worawattanakul Nikolaos L. Kelekis Gesine John John T. Woosley Mark Graham William G. Cance 《Journal of magnetic resonance imaging : JMRI》1997,7(6):1040-1047
This study compares liver lesion detection, characterization, and effect on patient management between single-phase spiral CT and MRI using spoiled gradient echo (SGE), T2-weighted fat-suppressed spin echo, and serial post gadolinium SGE. All patients with suspected liver lesions who underwent spiral CT and MRI within a 1-month period between January 1993 and September 1996 were included in the study. Spiral CT and MRI were interpreted prospectively in a blinded fashion by separate individual experienced investigators, and lesion detection and characterization were determined. Confirmation was obtained by surgery (6 patients), biopsy (18 patients), imaging follow-up (36 patients), or combined reading of all imaging studies and clinical follow-up (29 patients). Effect on patient management was determined by combined chart review and interview of the patients' physicians and by retrospective clinical assessment performed by a surgical oncologist and medical oncologist separately. Eighty-nine patients were included in the study. Regarding true positive lesion detection, 295 and 519 lesions were detected on spiral CT and MR images, respectively, which was significantly different on a patient-by-patient basis (P < .001). More lesions were detected on MR than on spiral CT in 44 of 89 patients (49.4%), and 11 of these 44 patients had lesions shown on MRI in whom no lesions were apparent on CT images. No patients had true positive lesions shown on spiral CT that were not shown on MRI. Regarding lesion characterization, 129 and 466 lesions were characterized on spiral CT and MRI images, respectively, which was significantly different on a patient-by-patient basis (P < .001). More lesions were characterized on MR than CT images in 67 patients (75.3%). Regarding effect on patient management, chart review with physician interview demonstrated that findings on MRI provided information that altered patient management as compared with findings on spiral CT in 57 patients. Retrospective clinical evaluation by the surgical and medical oncologist showed that MRI was considered to have a greater effect on patient management than spiral CT in 58 and 55 patients, respectively. Comparing current MRI technique to single-phase spiral CT, MRI detected more lesions in 49.4% and characterized more lesions in 75.3% of patients investigated for focal liver disease. MRI had a greater effect on patient management in each of the three methods than singlephase spiral CT in more than 61% of patients. 相似文献
124.
125.
Rounded atelectasis, a rare, benign mass lesion, is most often seen in association with asbestos-related pleural changes. Often a presumptive diagnosis can be made on the basis of characteristic CT and chest radiographic findings. However, not infrequently radiographic imaging fails to differentiate rounded atelectasis from primary bronchogenic carcinoma, a disease which is seen with increased frequency in patients with asbestos exposure. We describe two cases where the diagnosis of rounded atelectasis was made by fine-needle aspiration (FNA) cytology. The cytologic features included abundant pulmonary parenchymal material with thickened alveolar walls containing pulmonary macrophages and connective tissue. It is important to realize that this is a useful positive finding indicating rounded atelectasis, rather than a negative finding suggesting the absence of neoplasm. Needles with a cutting action may be necessary to obtain sufficient material to make the diagnosis of rounded atelectasis. 相似文献
126.
许东宝 《安徽卫生职业技术学院学报》2005,4(5):23-24
目的:探讨头颅CT对脑型脚气病的诊断价值,分析脑型脚气病的临床特点.方法:回顾性分析26例婴幼儿脑型脚气病的头颅CT及临床表现.结果:26例患儿主要临床表现为:惊厥、精神反应差、声嘶、呛奶、呆视、双眼睑下垂、四肢柔软、膝反射减弱或消失.头颅CT表现为双侧基底节时称性(25例)或单侧基底节(1例)低密度影,外部性脑积水2例.结论:脑型脚气病头颅CT具有一定特征性,可作为诊断脑型脚气病的依据之一. 相似文献
127.
目的了解我区部分医院X—CT检查占所有放射检查的比例,并分析2002至2004年X-CT各部位阳性检出率。方法分析X-CT诊断医疗照射频率的调查资料。结果CT检查占所有放射检查的比例为23.04%;除个别部位外,大部分阳性检出率均有所提高。结论X—CT检查的频率应予以控制,通过质控提高阳性检出率。 相似文献
128.
A. C. Iplikçioğlu M. A. Bayar F. Kökeş B. Yildiz C. Gökçek Z. Buharali 《Neuroradiology》1994,36(1):31-32
We report a fluid level in an acute extradural haematoma developing after placement of a ventriculoperitoneal shunt for hydrocephalus. This fluid level was thought to be due to a mixture of blood and cerebrospinal fluid. 相似文献
129.
Suzanne D. LeBlang M.D. Diego B. Nuñez M.D. Luis A. Rivas M.D. Steven Falcone M.D. Susan E. Pogson R.T. 《Emergency radiology》1997,4(4):200-206
The purpose of this study was to evaluate the ability of helical computed tomographic angiography (HCTA) to detect vascular injury in penetrating neck trauma. Thirty-five patients (30 gunshot wounds and 5 stab wounds) were studied prospectively with HCTA. Scans were performed with a 5-mm slice thickness at a 1:1 pitch after injection of 90 ml of nonionic contrast medium (30-second delay) at 3 ml/sec. Results were compared with those for angiography (29), surgery (3), ultrasound (2), and local inspection (1). HCTA correctly revealed 19 normal and 10 abnormal studies. In 8 cases, HCTA revealed irregular vessel margins (3), contrast extravasation (2), lack of vascular enhancement (1), and caliber changes (2). In 2 patients, HCTA revealed indirect signs of injury only. In 6 cases, HCTA findings did not correlate with angiography. HCTA detects both direct and indirect signs of vascular injury. Although indirect findings are more sensitive, the direct evaluation of vessels increases the specificity and has a high negative predictive value. 相似文献
130.
MRA与CTA头部血管成像技术探讨 总被引:2,自引:0,他引:2
目的 :探讨MRA与CTA成像技术的临床应用 ,选择合适的影像后处理方法。方法 :抽取MRA与CTA各 2 0份影像进行分析。结果 :两组病例MRA与CTA扫描后及处理均获得较好的影像信息。结论 :MRA与CTA的影像检查技术对临床诊断与治疗均各具有其优势并有其重要价值。 相似文献