全文获取类型
收费全文 | 1363680篇 |
免费 | 96651篇 |
国内免费 | 5020篇 |
专业分类
耳鼻咽喉 | 19911篇 |
儿科学 | 40620篇 |
妇产科学 | 38977篇 |
基础医学 | 190350篇 |
口腔科学 | 40317篇 |
临床医学 | 116390篇 |
内科学 | 266559篇 |
皮肤病学 | 30441篇 |
神经病学 | 107680篇 |
特种医学 | 54652篇 |
外国民族医学 | 447篇 |
外科学 | 211191篇 |
综合类 | 35750篇 |
现状与发展 | 12篇 |
一般理论 | 439篇 |
预防医学 | 93883篇 |
眼科学 | 32002篇 |
药学 | 103082篇 |
31篇 | |
中国医学 | 4553篇 |
肿瘤学 | 78064篇 |
出版年
2018年 | 12647篇 |
2016年 | 11465篇 |
2015年 | 13133篇 |
2014年 | 18212篇 |
2013年 | 26625篇 |
2012年 | 34826篇 |
2011年 | 37049篇 |
2010年 | 22133篇 |
2009年 | 21327篇 |
2008年 | 34994篇 |
2007年 | 38163篇 |
2006年 | 38689篇 |
2005年 | 37407篇 |
2004年 | 36146篇 |
2003年 | 35144篇 |
2002年 | 34559篇 |
2001年 | 64371篇 |
2000年 | 66010篇 |
1999年 | 56037篇 |
1998年 | 15052篇 |
1997年 | 13932篇 |
1996年 | 13250篇 |
1995年 | 12501篇 |
1994年 | 11685篇 |
1992年 | 42944篇 |
1991年 | 41465篇 |
1990年 | 40701篇 |
1989年 | 39673篇 |
1988年 | 37069篇 |
1987年 | 36516篇 |
1986年 | 34998篇 |
1985年 | 33160篇 |
1984年 | 24865篇 |
1983年 | 21074篇 |
1982年 | 12676篇 |
1981年 | 11576篇 |
1979年 | 23953篇 |
1978年 | 17083篇 |
1977年 | 14840篇 |
1976年 | 13394篇 |
1975年 | 15281篇 |
1974年 | 18088篇 |
1973年 | 17568篇 |
1972年 | 16817篇 |
1971年 | 15721篇 |
1970年 | 14915篇 |
1969年 | 14350篇 |
1968年 | 13462篇 |
1967年 | 12016篇 |
1966年 | 11262篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
Monatsschrift Kinderheilkunde - Fusionen und Übernahmen in der Pharmaindustrie haben zu einer Konzentration geführt, von der auch die Impfstoffproduktion mit nur noch wenigen global... 相似文献
93.
AbstractThe leading cause of death of adolescents in developed countries is injury. Alcohol is a major contributor to adolescent injury. Most of the injury deaths in youth are caused by traffic crashes. Driving under the influence (DUI) and riding with a driver who is under the influence (RUI) of alcohol increase the risk of road crash. The focus of this study is how adolescents’ risk of DUI and RUI differ in relation to their experience of parental control and peer pressure to substance use, other risky behaviours and leisure time activities. The analyses are based on data from the European School Survey Project on Alcohol and Other Drugs collected from 15- to 16-year-old Finnish adolescents in 2015 (n?=?4049, response rate 88.7%). The study shows that problems tend to entangle in some adolescent groups in which DUI and RUI are also more common. Adolescents with higher probability of using various substances, of starting alcohol use at young age, of experiencing weak parental control, and high peer pressure are at higher risk of DUI and RUI. The results indicate that professionals and authorities handling underage DUI and RUI ought to consider adolescents’ situation as a whole. 相似文献
94.
95.
C. Lukannek S. Shaefi K. Platzbecker D. Raub P. Santer S. Nabel H.S. Lecamwasam T.T. Houle M. Eikermann 《Anaesthesia》2019,74(9):1165-1174
Postoperative pulmonary complications are associated with an increase in mortality, morbidity and healthcare utilisation. The Agency for Healthcare Research and Quality recommends risk assessment for postoperative respiratory complications in patients undergoing surgery. In this hospital registry study of adult patients undergoing non-cardiac surgery between 2005 and 2017 at two independent healthcare networks, a prediction instrument for early postoperative tracheal re-intubation was developed and externally validated. This was based on the development of the Score for Prediction Of Postoperative Respiratory Complications. For predictor selection, stepwise backward logistic regression and bootstrap resampling were applied. Development and validation cohorts were represented by 90,893 patients at Partners Healthcare and 67,046 patients at Beth Israel Deaconess Medical Center, of whom 699 (0.8%) and 587 (0.9%) patients, respectively, had their tracheas re-intubated. In addition to five pre-operative predictors identified in the Score for Prediction Of Postoperative Respiratory Complications, the final model included seven additional intra-operative predictors: early post-tracheal intubation desaturation; prolonged duration of surgery; high fraction of inspired oxygen; high vasopressor dose; blood transfusion; the absence of volatile anaesthetic use; and the absence of lung-protective ventilation. The area under the receiver operating characteristic curve for the new score was significantly greater than that of the original Score for Prediction Of Postoperative Respiratory Complications (0.84 [95%CI 0.82–0.85] vs. 0.76 [95%CI 0.75–0.78], respectively; p < 0.001). This may allow clinicians to develop and implement strategies to decrease the risk of early postoperative tracheal re-intubation. 相似文献
96.
97.
目的 观察互动式歌唱表演对轻中度阿尔茨海默病(AD)患者抑郁、精神行为症状及运动训练参与率的影响。方法 选取符合入组条件≥60周岁AD患者63例,随机分为研究组(31例)和对照组(32例)。所有受试患者常规药物治疗及常规运动训练,对照组接受被动性音乐治疗,研究组接受以互动歌唱为主的主动性音乐治疗,1次/d,每次1小时,每周训练5天,持续干预6个月。于治疗前、治疗1个月后、治疗3个月后、治疗6个月后分别采用康奈尔痴呆抑郁量表(CSDD)评分、阿尔茨海默病病理行为(BEHAVE AD)评分、参与率进行评估。结果 治疗1个月、3个月后,研究组CSDD评分较治疗前均降低(P<0.05);治疗6个月后,研究组患者CSDD评分较治疗前、治疗1个月、3个月后均显著降低(P<0.05),且与对照组比较差异有统计学意义(P<0.05)。治疗1个月、3个月后,研究组BEHAVE AD评分较治疗前均降低(P<0.05);治疗6个月后,研究组患者BEHAVE AD评分较治疗前、治疗1个月、3个月后均显著降低(P<0.05),且与对照组比较差异有统计学意义(P<0.05)。治疗6个月后,两组运动训练参与率组间比较差异有统计学意义(P<0.05)。结论 互动式歌唱表演可能对改善轻中度AD患者的抑郁和精神行为症状有着积极的疗效,同时对提高受试者运动训练的参与率可能有着更积极的疗效。 相似文献
98.
Arjenne H.M. Gussenhoven Amika S. Singh S. Theo Goverts Marten van Til Johannes R. Anema Sophia E. Kramer 《International journal of audiology》2015,54(8):507-517
Objective: A multidisciplinary vocational rehabilitation programme, the Vocational Enablement Protocol (VEP) was developed to address the specific needs of employees with hearing difficulties. In the current study we evaluated the process of implementing the VEP in audiologic care among employees with hearing impairment. Design: In conjunction with a randomized controlled trial, we collected and analysed data on seven process parameters: recruitment, reach, fidelity, dose delivered, dose received and implemented, satisfaction, and perceived benefit. Study sample: Sixty-six employees with hearing impairment participated in the VEP. The multidisciplinary team providing the VEP comprised six professionals. Results: The professionals performed the VEP according to the protocol. Of the recommendations delivered by the professionals, 31% were perceived as implemented by the employees. Compliance rate was highest for hearing-aid uptake (51%). Both employees and professionals were highly satisfied with the VEP. Participants rated good perceived benefit from it. Conclusions: Our results indicate that the VEP could be a useful treatment for employees with hearing difficulties from a process evaluation perspective. Implementation research in the audiological setting should be encouraged in order to further provide insight into parameters facilitating or hindering successful implementation of an intervention and to improve its quality and efficacy. 相似文献
99.
Maria C. Chammas Andre C. Oliveira Mario J. D´Ávilla Pedro H. Moraes Marcelo Straus Takahashi 《Ultrasound in medicine & biology》2019,45(1):50-55
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease. 相似文献
100.
K.-C. Sung D.-C. Seo S.-J. Lee M.-Y. Lee S.H. Wild C.D. Byrne 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2019,29(5):489-495