全文获取类型
收费全文 | 373546篇 |
免费 | 19311篇 |
国内免费 | 1002篇 |
专业分类
耳鼻咽喉 | 4844篇 |
儿科学 | 11617篇 |
妇产科学 | 8733篇 |
基础医学 | 52794篇 |
口腔科学 | 13448篇 |
临床医学 | 25511篇 |
内科学 | 82891篇 |
皮肤病学 | 10598篇 |
神经病学 | 31045篇 |
特种医学 | 10916篇 |
外国民族医学 | 56篇 |
外科学 | 45397篇 |
综合类 | 2444篇 |
现状与发展 | 1篇 |
一般理论 | 94篇 |
预防医学 | 39812篇 |
眼科学 | 8114篇 |
药学 | 25847篇 |
2篇 | |
中国医学 | 1412篇 |
肿瘤学 | 18283篇 |
出版年
2023年 | 1872篇 |
2022年 | 3402篇 |
2021年 | 7304篇 |
2020年 | 4442篇 |
2019年 | 7171篇 |
2018年 | 10274篇 |
2017年 | 7068篇 |
2016年 | 6988篇 |
2015年 | 7867篇 |
2014年 | 10373篇 |
2013年 | 14235篇 |
2012年 | 22245篇 |
2011年 | 23133篇 |
2010年 | 12112篇 |
2009年 | 10515篇 |
2008年 | 18656篇 |
2007年 | 19846篇 |
2006年 | 18907篇 |
2005年 | 19033篇 |
2004年 | 17819篇 |
2003年 | 16431篇 |
2002年 | 14304篇 |
2001年 | 11304篇 |
2000年 | 11708篇 |
1999年 | 9792篇 |
1998年 | 3036篇 |
1997年 | 2427篇 |
1996年 | 2315篇 |
1995年 | 1974篇 |
1994年 | 1854篇 |
1993年 | 1685篇 |
1992年 | 5622篇 |
1991年 | 5314篇 |
1990年 | 5050篇 |
1989年 | 4705篇 |
1988年 | 4325篇 |
1987年 | 4022篇 |
1986年 | 3915篇 |
1985年 | 3689篇 |
1984年 | 2689篇 |
1983年 | 2259篇 |
1979年 | 2469篇 |
1975年 | 1684篇 |
1974年 | 1940篇 |
1973年 | 1987篇 |
1972年 | 1800篇 |
1971年 | 1715篇 |
1970年 | 1699篇 |
1969年 | 1761篇 |
1968年 | 1736篇 |
排序方式: 共有10000条查询结果,搜索用时 18 毫秒
61.
目的 收集藿香正气汤的主要活性成分,通过分子对接及网络药理学探讨其防控新型冠状病毒肺炎(COVID-19)的有效成分及治疗机制。方法 通过基于配体-蛋白质相互作用的计算方法,以瑞德西韦为对照,探索藿香正气汤潜在治疗COVID-19的成分,并选出对接较好成分进行药理学机制预测,初探其药理学机制。结果 本研究筛选出5种与新冠病毒3CLpro结合能力强于瑞德西韦的小分子成分。网络药理学初步预测抗病毒途径可能是通过PI3K-Akt 信号通路影响病毒复制。结论 成分C1-C5与3CLpro结合良好,推测其可能是潜在的3CLpro的抑制剂,为抗病毒天然药物的开发提供了理论依据。 相似文献
62.
63.
64.
65.
66.
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
67.
68.
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
69.
José Antonio Pereira Miguel Pera Manuel López-Cano Marta Pascual Sandra Alonso Silvia Salvans Marta Jiménez-Toscano Alba González-Martín Luis Grande-Posa 《Cirugía espa?ola》2019,97(1):20-26
Objectives
To determine the incidence of incisional hernia (IH) in the extraction incision (EI) in colorectal resection for cancer. To analyze whether the location of the incision has any relationship with the incidence of hernias and whether mesh could be useful for prevention in high-risk patients.Methods
Retrospective review of the colon and rectal surgery database from January 2015 to December 2016. Data were classified into 2 groups, transverse (TI) and midline incision (MI), and the latter was divided into 2 subgroups (mesh [MIM] and suture [MIS]). Patients were classified using the HERNIAscore. Hernias were diagnosed by clinical and/or CT examination.Results
A total of 182 out of 210 surgical patients were included. After a median follow-up of 13.0 months, 39 IH (21.9%) were detected, 23 of which (13.4%) were in the EI; their frequency was lower in the TI group (3.4%) and in the MIM group (5.9%) than in the MIS group (29.5%; p = 0.007). The probability of developing IH in the MIS group showed an OR = 11.7 (95%CI: 3.3-42.0) compared to the TI group and 4.3 (IC 95%: 1.1-16.3) versus the MIM group.Conclusions
The location of the incision is relevant to avoid incisional hernias. Transverse incisions should be used as the first option. When a midline incision is needed, a prophylactic mesh could be considered in high risk patients because it is safe and associated with low morbidity. 相似文献70.