全文获取类型
收费全文 | 20678篇 |
免费 | 1874篇 |
国内免费 | 496篇 |
专业分类
耳鼻咽喉 | 212篇 |
儿科学 | 575篇 |
妇产科学 | 209篇 |
基础医学 | 1377篇 |
口腔科学 | 328篇 |
临床医学 | 1448篇 |
内科学 | 4088篇 |
皮肤病学 | 466篇 |
神经病学 | 1642篇 |
特种医学 | 387篇 |
外国民族医学 | 1篇 |
外科学 | 1731篇 |
综合类 | 2631篇 |
预防医学 | 4951篇 |
眼科学 | 360篇 |
药学 | 923篇 |
8篇 | |
中国医学 | 222篇 |
肿瘤学 | 1489篇 |
出版年
2024年 | 48篇 |
2023年 | 331篇 |
2022年 | 765篇 |
2021年 | 1001篇 |
2020年 | 955篇 |
2019年 | 893篇 |
2018年 | 952篇 |
2017年 | 805篇 |
2016年 | 821篇 |
2015年 | 795篇 |
2014年 | 1660篇 |
2013年 | 1548篇 |
2012年 | 1343篇 |
2011年 | 1432篇 |
2010年 | 1134篇 |
2009年 | 1090篇 |
2008年 | 1005篇 |
2007年 | 954篇 |
2006年 | 831篇 |
2005年 | 677篇 |
2004年 | 470篇 |
2003年 | 407篇 |
2002年 | 353篇 |
2001年 | 327篇 |
2000年 | 270篇 |
1999年 | 235篇 |
1998年 | 196篇 |
1997年 | 172篇 |
1996年 | 144篇 |
1995年 | 127篇 |
1994年 | 109篇 |
1993年 | 105篇 |
1992年 | 122篇 |
1991年 | 104篇 |
1990年 | 105篇 |
1989年 | 70篇 |
1988年 | 80篇 |
1987年 | 71篇 |
1986年 | 47篇 |
1985年 | 89篇 |
1984年 | 62篇 |
1983年 | 47篇 |
1982年 | 49篇 |
1981年 | 52篇 |
1980年 | 30篇 |
1979年 | 37篇 |
1978年 | 26篇 |
1977年 | 24篇 |
1976年 | 27篇 |
1975年 | 25篇 |
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
51.
Leonora Q. Schwandt Henri-Jacques Tjong-Ayong Ranny van Weissenbruch Henny C. der Mei Frans W. J. Albers 《European archives of oto-rhino-laryngology》2006,263(6):518-523
Tracheoesophageal voice prostheses need to be replaced due to increased airflow resistance or retrograde leakage of fluid into the trachea as a consequence of biofilm formation. Previous in vitro studies show a change of aerodynamic features of biofilm covered voice prostheses after removal of the prostheses out of the patient. To assess these changes in an in situ situation, aerodynamic characteristics were measured within 45 patients at the beginning and at the end of the wearing process of the Provox 2 voice prosthesis. As a consequence, the influence of biofilm formation on aerodynamic characteristics can be evaluated. In the majority of cases, leakage through the prosthesis was the reason for replacement. No differences were found in the total flow, volume range and intratracheal pressure (ITP) of the voice prostheses measured. The airflow resistance of biofilm covered prostheses was significantly reduced compared to new clean prostheses. However, no correlation was found between the extent of biofilm and the different aerodynamic features measured. Biofilm formation on the Provox 2 is responsible for both reduction in airflow resistance and leakage through the prosthesis by deterioration of the silicone rubber material. 相似文献
52.
We report a rare example of bilateral primary malignant phyllodes tumours. The diagnosis was supported by the identification of a benign epithelial element in each lesion. The case illustrates the typical dimorphic features of malignant phyllodes tumours. A contralateral tumour should not be regarded as metastatic without histological confirmation. 相似文献
53.
Pseudomonas cepacia has recently emerged as an important nosocomial pathogen. We analyzed a national nosocomial infections database, the National Nosocomial Infections Surveillance (NNIS) system, to describe the epidemiology of endemic nosocomial P. cepacia infections. Between 1980 and 1985, the P. cepacia nosocomial infection rate was 2.4 per 100,000 patient discharges. During this period, there was a significant increase in the P. cepacia infection rate. The highest infection rate was reported from large medical school-affiliated hospitals. Over 90% of the infections were reported from medicine and surgery services. The most frequently reported site of infection was the lower respiratory tract (31%), followed by blood (20%) and the urinary tract (20%). Nosocomial P. cepacia infections are often associated with mortality, particularly when they involve the lung. These data confirm the hypothesis that P. cepacia is an emerging nosocomial pathogen and suggest that the epidemiology of endemic infections differs from that reported for epidemic inflections. 相似文献
54.
咽旁间隙原发性肿块流行病学分析 总被引:1,自引:0,他引:1
目的:对咽旁间隙原发性肿块进行流行病学分析。方法:对咽旁间隙原发性239例肿块进行统计分析。结果:原发良性肿瘤患病比为61.09%,其中上皮源性肿瘤患病比最高,占19.25%;神经源性肿瘤第二位,占17.57%。原发性恶性肿瘤的患病比为35.15%,其中上皮源性恶性肿瘤的患病比最高,占21.76%;恶性淋巴瘤第2位,占7.95%。炎症的患病比为3.77%,其中淋巴结反应性增生最高。结论:咽旁间隙原发性肿块良性肿瘤的患病比最高,恶性肿瘤次之,炎症居第3位,比例约为17:9:1。 相似文献
55.
目的 了解社区老年人支气管哮喘的患病情况 ,为哮喘防治奠定基础。 方法 采用整群抽样 ,对南海市桂城社区 2 481名 60岁以上老年人进行哮喘的流行病学调查。 结果 确诊老年人哮喘 98例 ,患病率为 3 .95 % (男4.91%、女 2 .92 % ) ,男性高于女性 (P <0 .0 5 ) ;工业区老年人哮喘的患病率高于文化区 (患病率分别为 5 .12 %、3 .2 6% ,P<0 .0 5 ) ;有遗传家族史者 45例 ,占 45 .92 % ;78%的患者发病年龄 >14岁 ;诱发因素前 3位分别是上呼吸道感染、气候变化和刺激性气体 ;合并COPD2 5例 ,占 2 5 .5 1%。 结论 老年人哮喘是不容忽视的疾病 ,需加强对社区哮喘的管理和教育。 相似文献
56.
重型病毒性肝炎合并急性胰腺炎的临床分析 总被引:2,自引:0,他引:2
目的通过对重型病毒性肝炎合并急性胰腺炎的病例进行分析,以找出其临床特点.方法对上述病例的临床症状、实验室检查、治疗情况、病情的发生发展及预后进行分析.结果少数患者表现不典型或胰腺炎的症状被重型肝炎的严重症状所掩盖,容易发生漏诊及误诊;且病情发展快、预后差.结论只有对相应患者尽早做血、尿淀粉酶的测定并反复复查,才能做到及时诊断和治疗. 相似文献
57.
不同性别首次发作抑郁症的临床特征对比 总被引:3,自引:1,他引:2
目的:探讨不同性别首次发作抑郁症临床特征的异同。方法:采用一般情况问卷、抑郁白评量表(SDS)和汉密顿抑郁量表(HAMD)对不同性别首发抑郁症患者进行测查。结果:女性首发抑郁症患者发病年龄显著低于男性,HAMD的躯体化/焦虑、睡眠因子显著高于男性,而认识障碍、迟缓和绝望因子评分显著较男性为低。另外,女性抑郁症患者的共病显著高于男性。结论:不同性别首次发作抑郁症的临床特征存在一定的差异。 相似文献
58.
为了解医院腹泻病门诊病人分布、诊断和治疗情况,对广西5个腹泻病控制规划县(市)级医院1995年6月1日 ̄15日腹泻病门诊登记的资料进行分析。5个医院腹泻病人共1051人,其中男性占52.0%,女性占47.9%;以肠炎最高占79.7%,其次痢疾占20.2%;轻度脱水病人占46.7%,无脱水病人占37.9%;以〈5岁儿童发病数最高,占28.8%,静脉输液使用率为18.85%,口服补液盐(ORS)使用率 相似文献
59.
Martin Døssing Steffen Groth Jørgen Vestbo Ole Lyngenbo 《International archives of occupational and environmental health》1990,62(3):209-212
Summary Among 701 Copenhagen plumbers we examined the lung function of 23 never smokers, who had removed asbestos insulation and intermittently been exposed to high levels of asbestos for about 25 years without being exposed to welding fume. The plumbers had significantly lower TLC, MEF25, MEF50, closing volume and closing capacity in comparison to 23 never smoking electricians without asbestos exposure. There was no reduction in TLCO. Pulmonary clearance of aerosolized 99mTc-DTPA was normal indicating that the asbestos had not induced increases in pulmonary epithelial permeability. However, in 11 of the 23 plumbers the 99m-Tc-DTPA ventilation scintigrams had a slightly irregular and spotty appearance, which together with the results of the lung function tests are suggestive of small airways' dysfunction. None of the subjects had symptoms or clinical signs of lung disease. 相似文献
60.
John N. K. Hsiang Keith Y. C. Goh Xian-Lun Zhu Wai S. Poon 《Child's nervous system》1996,12(10):611-614
Head injury in children causes special concern in most communities. From 1989 to 1994, 2,785 children younger than 16 years old were admitted to our neurosurgical service because of head injury. Fall from a height was the major cause of head injury leading to admission in infants and children in preschool age groups, whereas traffic-related or bicycle-related accidents were more likely to be the cause of head injury for those aged 11–15 years. In all age groups there was a male preponderance. The overall mortality was 0.6%. Traffic-ralated accidents caused more severe injury and accounted for 67% of all fatalities. For patients under 6 years old, about 40% of head injuries occurred at home. Preventive measures for pediatric head injury in Hong Kong are suggested. 相似文献