全文获取类型
收费全文 | 67053篇 |
免费 | 5396篇 |
国内免费 | 209篇 |
专业分类
耳鼻咽喉 | 661篇 |
儿科学 | 2622篇 |
妇产科学 | 1823篇 |
基础医学 | 9349篇 |
口腔科学 | 1341篇 |
临床医学 | 8516篇 |
内科学 | 13614篇 |
皮肤病学 | 1475篇 |
神经病学 | 6668篇 |
特种医学 | 1719篇 |
外科学 | 7051篇 |
综合类 | 612篇 |
一般理论 | 82篇 |
预防医学 | 7177篇 |
眼科学 | 1079篇 |
药学 | 3950篇 |
2篇 | |
中国医学 | 92篇 |
肿瘤学 | 4825篇 |
出版年
2024年 | 90篇 |
2023年 | 618篇 |
2022年 | 933篇 |
2021年 | 2080篇 |
2020年 | 1433篇 |
2019年 | 2018篇 |
2018年 | 2267篇 |
2017年 | 1715篇 |
2016年 | 1910篇 |
2015年 | 2010篇 |
2014年 | 2574篇 |
2013年 | 3664篇 |
2012年 | 5154篇 |
2011年 | 5267篇 |
2010年 | 2885篇 |
2009年 | 2556篇 |
2008年 | 4158篇 |
2007年 | 4370篇 |
2006年 | 4154篇 |
2005年 | 3906篇 |
2004年 | 3749篇 |
2003年 | 3343篇 |
2002年 | 2985篇 |
2001年 | 600篇 |
2000年 | 468篇 |
1999年 | 538篇 |
1998年 | 676篇 |
1997年 | 500篇 |
1996年 | 436篇 |
1995年 | 411篇 |
1994年 | 353篇 |
1993年 | 345篇 |
1992年 | 306篇 |
1991年 | 290篇 |
1990年 | 256篇 |
1989年 | 234篇 |
1988年 | 229篇 |
1987年 | 193篇 |
1986年 | 210篇 |
1985年 | 209篇 |
1984年 | 201篇 |
1983年 | 185篇 |
1982年 | 210篇 |
1981年 | 225篇 |
1980年 | 173篇 |
1979年 | 147篇 |
1978年 | 140篇 |
1977年 | 114篇 |
1976年 | 90篇 |
1974年 | 85篇 |
排序方式: 共有10000条查询结果,搜索用时 34 毫秒
21.
Sabrina Ronco 《Nursing for Women's Health》2021,25(3):207-211
A review of the literature was performed to explore the association between prenatal education and rates of primary cesarean birth for women at low risk for cesarean birth. Most women who are nulliparous with a singleton fetus of term gestational age and in the vertex position are considered to be at low risk and favorable for a vaginal birth, yet the cesarean birth rate for women at low risk was 25.6% in 2019. It has been suggested that the rise in the cesarean birth rate among low-risk women may not be due to medical indications but, rather, to nonmedical factors, such as a provider’s or woman’s preference or lack of prenatal education. Evidence from this literature review supports the premise that prenatal education classes should be routinely incorporated into maternity care in an effort to reduce cesarean birth rates for the low-risk population. 相似文献
22.
23.
Harinakshi Sanikini David C. Muller Marisa Sophiea Sabina Rinaldi Antonio Agudo Eric J. Duell Elisabete Weiderpass Kim Overvad Anne Tjønneland Jytte Halkjær Marie-Christine Boutron-Ruault Franck Carbonnel Iris Cervenka Heiner Boeing Rudolf Kaaks Tilman Kühn Antonia Trichopoulou Georgia Martimianaki Anna Karakatsani Valeria Pala Domenico Palli Amalia Mattiello Rosario Tumino Carlotta Sacerdote Guri Skeie Charlotta Rylander María-Dolores Chirlaque López Maria-Jose Sánchez Eva Ardanaz Sara Regnér Tanja Stocks Bas Bueno-de-Mesquita Roel C.H. Vermeulen Dagfinn Aune Tammy Y.N. Tong Nathalie Kliemann Neil Murphy Marc Chadeau-Hyam Marc J. Gunter Amanda J. Cross 《International journal of cancer. Journal international du cancer》2020,146(4):929-942
Obesity has been associated with upper gastrointestinal cancers; however, there are limited prospective data on associations by subtype/subsite. Obesity can impact hormonal factors, which have been hypothesized to play a role in these cancers. We investigated anthropometric and reproductive factors in relation to esophageal and gastric cancer by subtype and subsite for 476,160 participants from the European Prospective Investigation into Cancer and Nutrition cohort. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox models. During a mean follow-up of 14 years, 220 esophageal adenocarcinomas (EA), 195 esophageal squamous cell carcinomas, 243 gastric cardia (GC) and 373 gastric noncardia (GNC) cancers were diagnosed. Body mass index (BMI) was associated with EA in men (BMI ≥30 vs. 18.5–25 kg/m2: HR = 1.94, 95% CI: 1.25–3.03) and women (HR = 2.66, 95% CI: 1.15–6.19); however, adjustment for waist-to-hip ratio (WHR) attenuated these associations. After mutual adjustment for BMI and HC, respectively, WHR and waist circumference (WC) were associated with EA in men (HR = 3.47, 95% CI: 1.99–6.06 for WHR >0.96 vs. <0.91; HR = 2.67, 95% CI: 1.52–4.72 for WC >98 vs. <90 cm) and women (HR = 4.40, 95% CI: 1.35–14.33 for WHR >0.82 vs. <0.76; HR = 5.67, 95% CI: 1.76–18.26 for WC >84 vs. <74 cm). WHR was also positively associated with GC in women, and WC was positively associated with GC in men. Inverse associations were observed between parity and EA (HR = 0.38, 95% CI: 0.14–0.99; >2 vs. 0) and age at first pregnancy and GNC (HR = 0.54, 95% CI: 0.32–0.91; >26 vs. <22 years); whereas bilateral ovariectomy was positively associated with GNC (HR = 1.87, 95% CI: 1.04–3.36). These findings support a role for hormonal pathways in upper gastrointestinal cancers. 相似文献
24.
25.
26.
27.
Nickel Allergy and Our Children's Health: A Review of Indexed Cases and a View of Future Prevention
下载免费PDF全文
![点击此处可从《Pediatric dermatology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sharon E. Jacob M.D. Alina Goldenberg M.D. M.A.S. Janice L. Pelletier M.D. Luz S. Fonacier M.D. Richard Usatine M.D. Nanette Silverberg M.D. 《Pediatric dermatology》2015,32(6):779-785
Nickel is the leading cause of allergic contact dermatitis (ACD) from early childhood through adolescence. Studies have shown that skin piercings and other nickel‐laden exposures can trigger the onset of nickel ACD in those who are susceptible. Nickel ACD causes a vast amount of cutaneous disease in children. Cases of nickel ACD in children have been reported in peer‐reviewed literature from 28 states. Common items that contain inciting nickel include jewelry, coins, zippers, belts, tools, toys, chair studs, cases for cell phones and tablets, and dental appliances. The diagnosis of nickel ACD has been routinely confirmed by patch testing in children older than 6 months suspected of ACD from nickel. Unlike in Europe, there are no mandatory restrictions legislated for nickel exposure in the United States. Denmark has demonstrated that regulation of the nickel content in metals can lower the risk of ACD and the associated health care–related costs that arise from excess nickel exposure. To further awareness, this article reviews the prominent role of nickel in pediatric skin disease in the United States. It discusses the need for a campaign by caretakers to reduce nickel‐related morbidity. Lastly, it promotes the model of European legislation as a successful intervention in the prevention of nickel ACD. 相似文献
28.
The association between family affluence and smoking among 15‐year‐old adolescents in 33 European countries,Israel and Canada: the role of national wealth
下载免费PDF全文
![点击此处可从《Addiction (Abingdon, England)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
29.
30.
Gregers Mads Christian Tofte Mikkelsen Søren Lindvig Katrine Prier Brøchner Anne Craveiro 《Neurocritical care》2020,33(1):273-282
Neurocritical Care - For years, the use of ketamine as an anesthetic to patients suffering from acute brain injury has been debated because of its possible deleterious effects on the cerebral... 相似文献