全文获取类型
收费全文 | 860521篇 |
免费 | 59075篇 |
国内免费 | 1700篇 |
专业分类
耳鼻咽喉 | 11254篇 |
儿科学 | 28317篇 |
妇产科学 | 20916篇 |
基础医学 | 131362篇 |
口腔科学 | 27077篇 |
临床医学 | 75198篇 |
内科学 | 169070篇 |
皮肤病学 | 20161篇 |
神经病学 | 62500篇 |
特种医学 | 30596篇 |
外国民族医学 | 101篇 |
外科学 | 123723篇 |
综合类 | 16061篇 |
现状与发展 | 3篇 |
一般理论 | 217篇 |
预防医学 | 67852篇 |
眼科学 | 19230篇 |
药学 | 63391篇 |
3篇 | |
中国医学 | 2989篇 |
肿瘤学 | 51275篇 |
出版年
2021年 | 8825篇 |
2019年 | 8616篇 |
2018年 | 12331篇 |
2017年 | 9428篇 |
2016年 | 9912篇 |
2015年 | 11214篇 |
2014年 | 15285篇 |
2013年 | 21705篇 |
2012年 | 30416篇 |
2011年 | 31865篇 |
2010年 | 17967篇 |
2009年 | 16596篇 |
2008年 | 27976篇 |
2007年 | 30078篇 |
2006年 | 29744篇 |
2005年 | 28653篇 |
2004年 | 27717篇 |
2003年 | 25999篇 |
2002年 | 23698篇 |
2001年 | 40573篇 |
2000年 | 41189篇 |
1999年 | 34182篇 |
1998年 | 9278篇 |
1997年 | 7828篇 |
1996年 | 8095篇 |
1995年 | 7591篇 |
1994年 | 7058篇 |
1993年 | 6466篇 |
1992年 | 25336篇 |
1991年 | 25199篇 |
1990年 | 24405篇 |
1989年 | 24168篇 |
1988年 | 21927篇 |
1987年 | 21191篇 |
1986年 | 20089篇 |
1985年 | 18873篇 |
1984年 | 13843篇 |
1983年 | 11654篇 |
1982年 | 6442篇 |
1979年 | 12366篇 |
1978年 | 8686篇 |
1977年 | 7271篇 |
1976年 | 6970篇 |
1975年 | 7767篇 |
1974年 | 9006篇 |
1973年 | 8646篇 |
1972年 | 8082篇 |
1971年 | 7495篇 |
1970年 | 7297篇 |
1969年 | 6727篇 |
排序方式: 共有10000条查询结果,搜索用时 296 毫秒
81.
82.
Moises Rodriguez-Gonzalez Antonio Moruno Tirado Reza Hosseinpour Jose Santos de Soto 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(4):350-356
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic. 相似文献
83.
84.
85.
86.
Qianlai Luo Jonathan N. Hofmann Ruth M. Pfeiffer Cari M. Kitahara Minkyo Song Meredith S. Shiels 《International journal of cancer. Journal international du cancer》2023,153(1):64-72
In the United States, renal cell carcinoma (RCC) incidence and the prevalence of obesity, an established risk factor for RCC, have been increasing for several decades. RCC is more common among older individuals. We sought to quantify the contribution of excess adiposity to the rising incidence of RCC among individuals 60 years or older. National Institutes of Health-American Association of Retired Persons Diet and Health Study data (n = 453 859 participants, enrolled in 1995-1996, age at enrollment 50-71 years) were used to estimate multivariable-adjusted hazard ratios (HRs) for RCC across body mass index categories and HRs associated with smoking. Population attributable fractions (PAFs) were calculated using estimated HRs and annual overweight/obesity prevalence from the National Health Interview Survey (1985-2008). PAF estimates were combined with RCC incidence from Surveillance, Epidemiology and End Results-13 to calculate annual percent changes in RCC incidence attributable (and unrelated) to overweight/obesity. We found that between 1995 and 2018, among individuals aged 60 years and older, PAF for overweight/obesity increased from 18% to 29% for all RCCs. In comparison, the PAF for smoking declined from 12% to 9%. RCC incidence increased 1.8% per year (95% confidence interval [CI] 1.5%-2.1%) overall, while RCC incidence attributable to overweight/obesity increased 3.8% per year (95%CI 3.5%-4.2%) and RCC incidence unrelated to overweight/obesity increased 1.2% per year (95% CI 0.9%-1.4%). In conclusion, overweight/obesity appears to have contributed importantly to the rising incidence of RCC in the United States since the mid-1990s. Public health interventions focused on reducing overweight and obesity could help substantially in curbing this trend. 相似文献
87.
Caio Henrique de Carvalho Assuno Júlio Csar Trabanco Raquel Fornaziero Gomes Renata Rodrigues Moreira Alessandra Giannella Samelli 《La Medicina del lavoro》2019,110(4):304
Objective:The present study evaluates a training program for fitting different hearing protection devices (HPDs) based on personal attenuation rating (PAR) before, immediately after, and six months after training.Methods:A total of 67 workers from a public university in the city of São Paulo, Brazil, were invited to participate in the measurement of PARs for foam and silicone protectors through the 3M™ E-A-Rfit Validation System. Two evaluations were performed for each protector at each sampling date: one after reading printed material (the package instructions) and another after being trained by an audiologist. The same procedures were repeated after six months. The final sample consisted of 30 individuals. ANOVA was used for statistical analysis.Results:Larger PAR values were observed after training by the audiologist, and smaller values were observed after six months. Then, after re-training, the values increased again. There were no statistically significant differences in PAR among the HPDs tested. Even after the two training sessions, 23 to 27% of the subjects did not obtain adequate PAR values.Conclusion:These findings emphasize the need for continual worker training in the correct fit of earplug HPDs and the importance of longitudinal PAR monitoring. In addition, some workers, despite the training provided, did not adapt to the HPDs used. Therefore, it is essential that other protection methods and/or other HPD types are made available to these individuals.Key words: Hearing, noise-induced hearing loss, occupational health, personal protective equipment, hearing protection devices 相似文献
88.
89.
90.