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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
赵树芳 《中国继续医学教育》2016,(5):41-43
目的探讨动脉导管未闭(PDA)合并重度肺动脉高压(PH)的超声心动图特点及诊断技巧。方法回顾性分析42例PDA合并重度PH患者的心脏二维超声改变、多普勒血流特点以及显示PDA切面。结果超声心动图诊断PDA合并重度PH符合率61.5%,误诊16例;二维超声的主要改变是肺动脉扩张、右心增大;彩色多普勒分流束及分流频谱是诊断的主要依据;左高位切面是诊断PDA合并重度PH的最易显示切面。结论 PDA合并重度PH的临床及超声特点与单纯PDA不一致,注重超声心动图检查思维与技巧有助于诊断及鉴别诊断。 相似文献
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Ya Zumeng Gao Zhi Zhang Gang Wang Jianhua Tan Yinghui 《Otolaryngology--head and neck surgery》2006,135(3):458-462
OBJECTIVE: To reduce the incidence of sensory deficits and Frey's syndrome by modifying the traditional superficial parotidectomy. STUDY DESIGN: After raising the skin flap, the parotid gland fascia (PGF) was elevated to form a posterior pedicle fascial flap and then was replaced after the gland removal. The great auricular nerve (GAN) that runs within the PGF was not separated, so both the GAN and the PGF were preserved. Before this modification, the GAN and PGF were examined anatomically. The complication rates in the modified and control groups were compared. RESULTS: 1) The GAN, which runs within the thick and pycnotic PGF, trifurcates into postauricular, preauricular and lobule branches. The modification could be carried out practically based on the anatomy study. 2) Long-term sensory deficit was encountered in 13.3% of the control group, but 0% in the modified one. Frey's syndrome was suffered by 66.7% and 16.7% cases in the control and modified group respectively. The incidence of other complications was not significantly different. CONCLUSION: Our modification is practical. It decreases the complications significantly. EBM rating: B-3b. 相似文献
34.
PINK1 mutations in sporadic early-onset Parkinson's disease. 总被引:5,自引:0,他引:5
Eng-King Tan Kenneth Yew Eva Chua K Puvan Hui Shen Esther Lee Kim-Yoong Puong Yi Zhao Ratnagopal Pavanni Meng-Cheong Wong Dominic Jamora Deidre de Silva Kyaw-Thu Moe Fung-Peng Woon Yih Yuen Louis Tan 《Movement disorders》2006,21(6):789-793
Pathogenic PINK1 mutations have been described in PARK6-linked Parkinson's disease (PD) patients of Asian origin. However, data on the frequency of PINK1 mutations in sporadic early-onset Parkinson's disease (EOPD) Asian patients are lacking. The objectives of this study were to report the frequency of PINK1 mutations of sporadic EOPD in an Asian cohort comprising of ethnic Chinese, Malays, and Indians, and to highlight a PINK1-positive patient who presented with restless legs symptoms. Eighty consecutive sporadic EOPD patients from the movement disorder clinics of two major tertiary institutions in the country were included. We performed sequence analysis of all the coding and exon-intron junctions of the PINK1 using specific primer sets. In addition, we genotyped polymorphisms detected from the analysis in a group of sporadic PD patients and controls. Three different mutations (two homozygous nonsense and one heterozygous missense) in the putative kinase domain were found in three patients, giving a 3.7% frequency of PINK1 mutations in our EOPD cohort. All the mutations were absent in 200 healthy controls. One patient with a novel homozygous nonsense PINK1 mutation presented unusually with restless legs symptoms. Separately, analysis of the frequency of four PINK1 polymorphisms in a group of sporadic PD and controls did not reveal any significant differences. We highlight a 3.7% frequency of PINK1 mutations in an Asian cohort (ethnic Chinese, Malay, and Indian) of EOPD. The phenotypic spectrum associated with PINK1-positive patients may be wider than previously reported. Polymorphisms of PINK1 do not appear to modulate risk of PD in our population. 相似文献
35.
A R Molina H Brasch S T Tan 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(12):1458-1462
One serious complication of neurofibromatosis type 1 (NF1) is the development of malignant peripheral nerve sheath tumours (MPNSTs). These malignancies often develop within pre-existing plexiform neurofibromas and their development is now thought to be associated with both tumour suppressor gene mutations and dysregulated growth factor signalling. Recent work demonstrates that the lifetime risk of malignant transformation is significantly greater than previously thought. Ionising radiation, a long-standing disease, particularly the presence of a large number of plexiform neurofibromas from an early age, are suggested risk factors. We present an NF1 patient who developed an MPNST of the cervical vagus nerve which was successfully treated with surgery. Close monitoring of patients with NF and a high level of suspicion towards rapidly enlarging and painful swellings is merited as these features may signify malignant transformation. Whether a positive history of MPNST in other affected family members predisposes the individual to a higher risk of malignant transformation is unclear. 相似文献
36.
慢性阻塞性肺疾病及肺心病中医证型与左心功能及血气分析的关系 总被引:1,自引:0,他引:1
目的探讨慢性阻塞性肺疾病(COPD)及肺心病不同中医证型左心功能指标的变化及血气分析的关系。方法研究组60例,其中COPD患者33例,合并肺心病患者27例,所有患者根据中医辨证分型分为痰热壅肺证(20例)、痰湿蕴肺证(13例)、气阴两虚证(15例)和阳虚水泛证(12例);正常组15例来自本院体检正常者。研究组于入选当时按观察表详细记录患者症状、体征及舌脉情况,研究组和正常组均于48h内完成心功能检测和血气分析。比较研究组与正常组之间、研究组各证型之间心功能指标和血气分析的变化。结果(1)与正常组比较,研究组CI、ACI明显降低,STP、SVRI及TFC明显升高。(2)研究组各证型之间比较:气阴两虚与实证比较,CI明显降低,SVRI、TFC明显升高;阳虚水泛与实证比较,CI、LCWI明显降低,STR明显升高,SVRI、TFC明显升高;阳虚水泛与气阴两虚比较,只STR有明显差异。(3)各证型之间血气分析:阳虚水泛PaO2最低,其次为气阴两虚,阳虚水泛与实证比较差异明显。结论COPD及肺心病患者存在一定程度左心功能障碍,心功能指标可以作为评定COPD病情变化及证型演变的参考指标;显著的低氧血症是阳虚水泛证患者左心功能指标改变的重要原因。 相似文献
37.
Jonathan Larkin Anne Bost John I Glass Seng-Lai Tan 《Journal of interferon & cytokine research》2006,26(12):854-865
Hepatitis C virus (HCV)-specific impairments in host immunity have been described at multiple levels of the innate and adaptive response, which may lead to viral persistence in the majority of infections. Understanding of HCV-associated immune defects could lead to novel therapeutic advances. Natural killer (NK) cells, the major effector cells of the innate immune system, are functionally impaired in chronic HCV infection. It has been suggested that this phenotype is a result of virus-specific defects in antigen-presenting cells (APCs) that regulate NK cell activity, as normal NK function is restored when they are stimulated ex vivo. In this study, we used human NK cell cytotoxicity assays to evaluate the activation-induced effects of NK cells on the HCV replicon-containing hepatic cells. We found that cytokine-activated NK cells were capable of inducing an HCV-associated, perforin/granzyme-dependent lysis of human hepatoma cells and that this required direct cellular contact and was independent of MHC class I expression levels. In contrast, on removal of cytokine stimulation, NK cells failed to exert any direct cytolytic effect on replicon targets. These findings suggest an important underlying mechanism by which NK cells control HCV infection and, with appropriate understanding of HCV-associated immune defects, could lead to novel therapeutic advances. 相似文献
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