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71.
Linkage studies and mutation analysis of the PDEB gene in 23 families with Leber congenital amaurosis. 总被引:1,自引:0,他引:1
The phenotype in the rd mouse is similar to the clinical presentation of Leber congenital amaurosis (LCA) in humans. Recently a nonsense mutation in the beta subunit of the cGMP phosphodiesterase (Pdeb) gene has been defined as the cause for the rd phenotype in the mouse and has raised the question as to whether mutations in the human PDEB gene might cause LCA. We have previously cloned and characterized the human homologue of the mouse Pdeb gene and have mapped it to chromosome 4p16.3. In this study, a total of 23 LCA families of various ethnic backgrounds have been investigated. Linkage analysis using highly polymorphic (CA)n microsatellites has excluded the PDEB gene as a cause for LCA in 6 families. In the remaining 17 families, we have searched for mutations in the 22 exons of the PDEB gene using single-strand gel electrophoresis (SSGE). Multiple exonic polymorphisms have been determined. However, no DNA changes in the PDEB gene have been identified in our study population which could be causative for the LCA phenotype. 相似文献
72.
R. Padovani N. Acciarri M. Giulioni R. Pantieri M. P. Foschini 《European spine journal》1997,6(5):298-303
Cavernous angiomas, also called cavernous malformations or cavernomas, are vascular hamartomas accounting for 3–16% of all angiomatous lesions of the spinal district. Although histologically identical, these vascular anomalies may exhibit different clinical behavior and radiological features, depending on their location, hinting at different managements and therapeutic approaches. The authors report 11 cases of symptomatic spinal cavernous angiomas diagnosed and surgically treated over the past 18 years. Age of patients ranged from 15–75 years; males outnumbered females. Three patients had vertebral cavernous malformations, secondarily invading the epidural space; two had pure epidural lesions; two patients had intradural extramedullary lesions, and four intramedullary lesions. Surgical removal was completely achieved in four patients with intramedullary lesions, in two with subdural extramedullary lesions, and in one with a pure epidural lesion. Subtotal excision of another one epidural and three vertebral cavernous angiomas was followed by radiotherapy. There was no morbidity related to surgery; the mean follow-up was 2 years. The outcome was excellent in two cases, good in six, and unchanged in the other three. The authors discuss the different modalities of treatment of these vascular lesions variously placed along the spine. 相似文献
73.
T.-H. ZHOU X.-H. REN D.-L. YIN Y.-L. WU M. Li C.-Z. Lu D.-C. Wu Y.-Q. Wu Y.-Q. PENG Y.-P. WANG L. MA G. PEI 《Acta anaesthesiologica Scandinavica》1997,41(8):1077-1079
Congenital analgesia is a rare genetic disorder. We report here that a 12-year-old boy was able to recover from congenital insensitivity to pain. Neurological examinations revealed that there was a 'stocking' distribution of pain decrement on the lower extremities under the patient's knee joints. Magnetic Resonance Imaging (MRI) of his brain showed gyrus thinning with sulcus widening at both sides of the parietal lobe. Southern blot hybridization probed with cDNAs of various opioid receptors did not detect any significant abnormality. Our results suggest that this rare case may not be genetically determined. 相似文献
74.
小鼠肝癌细胞H22对淋巴内皮细胞flt-4、c-fos、PCNA表达的影响 总被引:2,自引:1,他引:1
目的:初步探讨有自发淋巴转移特性的肝癌细胞对淋巴内皮细胞增殖的影响。方法:弗氏不完全佐剂诱导Balb/c小鼠腹腔良性淋巴管瘤,分离瘤体消化法体外培养淋巴内皮细胞;H22细胞接种Balb/c小鼠腹腔,收集腹水制成H22条件培养液,观察其对淋巴内皮细胞生长和表达flt-4、c-fos、PCNA的影响。结果:小鼠淋巴管瘤来源的淋巴内皮细胞可成单层贴壁培养,在内皮细胞完全培养液和H22条件培养液作用下可增殖达到或接近铺满状态,并阳性表达flt-4、c-fos、PCNA,普通培养液不能支持细胞生长,flt-4等染色为阴性:结论:淋巴内皮细胞增殖可能是癌细胞淋巴路转移的必要条件。 相似文献
75.
头面部复杂动静脉畸形的栓塞治疗 总被引:2,自引:0,他引:2
目的 研究经导管栓塞技术在头面部动静脉畸形治疗中的应用。方法 3 0例头面部动静脉畸形患者共接受 40次栓塞治疗。其中使用国产TH胶栓塞者为 18例 2 0次 ,使用进口PVA微粒栓塞者为 12例 2 0次。结果 3 0例患者均成功实行瘤灶供血动脉栓塞术。所有患者栓塞术后临床症状明显改善 ,如瘤体缩小甚至消失 ,皮温降低 ,搏动感和血管杂音减弱或消失等。术后随访3~ 6个月 ,12例复发。全部病例均无严重并发症。结论 对于头面部动静脉畸形的患者来说 ,经导管栓塞术是一种较好的非手术治疗方法 ,在栓塞剂的选择方面 ,则以PVA微粒栓塞更为理想。 相似文献
76.
77.
78.
彩色多普勒超声和二维超声心动图并用,不仅可观察和了解心脏解剖、形态及腔室大小,又能观察血流动力学改变。我们从1991年11月至1992年11月间应用上述方法诊断先天性心脏病共18例,均经我院和外院手术证实:室间隔缺损7例;房间隔缺损6例;动脉导管未闭5例,其中1例误诊为肺动脉瓣狭窄,诊断准确率达94.4%。我们认为彩色多普勒诊断先天性心脏病方法安全,准确无损伤,为临床及术前提供了较可靠的诊断依据,但检查者必须了解心脏及大血管的解剖关系,结合临床才能提高诊断准确率,减少漏、误诊的发生。 相似文献
79.
Congenital pseudarthrosis of the clavicle is very rare. We report the results of two cases, one managed conservatively and
the second surgically. Neither patient had functional deficit, but the one treated surgically ended up with a scar, persisting
non-union and a short clavicle. Surgical treatment should be discouraged for this condition.
Received: 17 June 2002, Accepted: 17 July 2002 相似文献
80.
Tomoyuki TAKANO Masaki OHNO Tsunekazu YAMANO Morimi SHIMADA 《Congenital anomalies》1991,31(3):129-139
Abstract This study was undertaken to elucidate the pathogenesis of the hydrocephalus and aqueductal stenosis induced by intracerebral mumps virus inoculation in suckling hamsters.
Mild ventricular dilatation became apparent after 5 days of inoculation. Focal denuding of the ependymal layer and subsequent aqueductal stenosis were observed by 14 days after inoculation. The virus antigen was detected not only in the ependymal cells and choroid plexus, but also in some neurons in the cerebral cortex, hippocampus, midbrain and cerebellum. In the cerebral aqueduct, the orderly arrangement of the cilialy clusters was destroyed on the 5th day after inoculation. After 10 days, proliferation of GFAP positive cells was noticed around the cerebral aqueduct and subsequently caused aqueductal stenosis. In the advanced state of hydrocephalus, the cerebellum was displaced downward and showed an elongated, atrophic and sleevelike structure similar to the Arnold-Chiari malformation. It was suggested that the extensive damage of the ependymal cilia may account for early ventricular dilatation, and subsequent aqueductal stenosis with glial proliferation is the main cause of the advanced hydrocephalus. It has not yet been determined whether the mumps virus can pass through the human placenta or not. If it can, however, our results strongly suggest that mumps virus infection in the human fetus will cause congenital hydrocephalus. 相似文献
Mild ventricular dilatation became apparent after 5 days of inoculation. Focal denuding of the ependymal layer and subsequent aqueductal stenosis were observed by 14 days after inoculation. The virus antigen was detected not only in the ependymal cells and choroid plexus, but also in some neurons in the cerebral cortex, hippocampus, midbrain and cerebellum. In the cerebral aqueduct, the orderly arrangement of the cilialy clusters was destroyed on the 5th day after inoculation. After 10 days, proliferation of GFAP positive cells was noticed around the cerebral aqueduct and subsequently caused aqueductal stenosis. In the advanced state of hydrocephalus, the cerebellum was displaced downward and showed an elongated, atrophic and sleevelike structure similar to the Arnold-Chiari malformation. It was suggested that the extensive damage of the ependymal cilia may account for early ventricular dilatation, and subsequent aqueductal stenosis with glial proliferation is the main cause of the advanced hydrocephalus. It has not yet been determined whether the mumps virus can pass through the human placenta or not. If it can, however, our results strongly suggest that mumps virus infection in the human fetus will cause congenital hydrocephalus. 相似文献