全文获取类型
收费全文 | 14987篇 |
免费 | 784篇 |
国内免费 | 71篇 |
专业分类
耳鼻咽喉 | 128篇 |
儿科学 | 289篇 |
妇产科学 | 463篇 |
基础医学 | 1799篇 |
口腔科学 | 516篇 |
临床医学 | 1210篇 |
内科学 | 4286篇 |
皮肤病学 | 373篇 |
神经病学 | 1337篇 |
特种医学 | 306篇 |
外科学 | 2174篇 |
综合类 | 95篇 |
一般理论 | 2篇 |
预防医学 | 1087篇 |
眼科学 | 212篇 |
药学 | 789篇 |
中国医学 | 69篇 |
肿瘤学 | 707篇 |
出版年
2024年 | 10篇 |
2023年 | 153篇 |
2022年 | 370篇 |
2021年 | 626篇 |
2020年 | 327篇 |
2019年 | 511篇 |
2018年 | 674篇 |
2017年 | 392篇 |
2016年 | 406篇 |
2015年 | 459篇 |
2014年 | 695篇 |
2013年 | 813篇 |
2012年 | 1277篇 |
2011年 | 1291篇 |
2010年 | 655篇 |
2009年 | 586篇 |
2008年 | 998篇 |
2007年 | 918篇 |
2006年 | 890篇 |
2005年 | 862篇 |
2004年 | 758篇 |
2003年 | 597篇 |
2002年 | 599篇 |
2001年 | 67篇 |
2000年 | 66篇 |
1999年 | 80篇 |
1998年 | 92篇 |
1997年 | 63篇 |
1996年 | 70篇 |
1995年 | 59篇 |
1994年 | 46篇 |
1993年 | 33篇 |
1992年 | 38篇 |
1991年 | 25篇 |
1990年 | 23篇 |
1989年 | 19篇 |
1988年 | 18篇 |
1987年 | 11篇 |
1986年 | 24篇 |
1985年 | 19篇 |
1984年 | 22篇 |
1983年 | 17篇 |
1982年 | 23篇 |
1981年 | 20篇 |
1980年 | 22篇 |
1979年 | 8篇 |
1978年 | 12篇 |
1974年 | 11篇 |
1973年 | 19篇 |
1972年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
Sanchez SE Qiu C Perales MT Lam N Garcia P Williams MA 《European journal of obstetrics, gynecology, and reproductive biology》2008,137(1):50-55
OBJECTIVE: Mounting evidence supports the view that intimate partner violence (IPV) is an important cause of maternal mortality. Some, but not all, prior studies suggest that IPV is associated with increased risks of maternal medical conditions such as hypertensive disorders of pregnancy which are leading causes of maternal mortality worldwide. We assessed the relation between IPV and risk of preeclampsia among Peruvian women. STUDY DESIGN: We conducted a case-control study at two large hospitals in Lima, Peru. Preeclampsia cases were 339 women with pregnancy-induced hypertension and proteinuria (i.e., preeclampsia). Controls were 337 normotensive women. Information concerning women's exposure to physical and emotional violence during pregnancy was collected during in-person interviews conducted after delivery and while patients were in hospital. Odds ratios (OR) and 95% confidence intervals (CI) were estimated from logistic regression models. RESULTS: The prevalence of IPV was 43.1% among cases and 24.3% among controls. Compared with those reporting never exposure to IPV during pregnancy, women reporting any exposure had a 2.4-fold increased risk of preeclampsia (OR=2.4; 95% CI: 1.7-3.3). The association was strengthened slightly after adjusting for maternal age, parity and pre-pregnancy adiposity (OR=2.7; 95% CI: 1.9-3.9). Emotional abuse in the absence of physical violence was associated with a 3.2-fold (95% CI: 2.1-4.9) increased risk of preeclampsia. Emotional and physical abuse during pregnancy was associated with a 1.9-fold increased risk of preeclampsia (95% CI: 1.1-3.5). CONCLUSIONS: IPV among pregnant women is common and is associated with an increased risk of preeclampsia. These data support recent calls for coordinated global health efforts to prevent violence against women. 相似文献
53.
54.
55.
ngel Gimnez-Richarte Mabel Ortiz de Salazar Cristina Arbona María P. Gimnez-Richarte Miriam Collado Pedro L. Fernndez Francisco Quiles Carlos Clavijo Pascual Marco Jose-Manuel Ramos-Rincon 《Trasfusione del sangue》2022,20(4):267
BackgroundBlood transfusion centres should understand the epidemiology of emerging diseases that are transmissible through the transfusion of blood components. The risk of transmission of arboviruses through this route has become apparent in recent years. The aim of our study is to summarise the reported prevalence (viraemic rate, seroprevalence and/or antigen detection) of Chikungunya (CHIKV), Dengue (DENV) and Zika (ZIKV) viruses in blood donors according to screening test used and world region.Materials and methodsWe conducted a systematic literature review and meta-analysis having searched for information in the main bibliographic databases (MEDLINE, Embase, and Scopus). The prevalence for each of the viruses was calculated according to the screening test used and geographic location.ResultsWe included 18 records on CHIKV, 71 on DENV, and 27 on ZIKV. The highest prevalences of RNA for CHIKV were 1.9% in Puerto Rico (2014), 1.0% in Thailand (2009), and 1.0% in French Polynesia (2014–15). The highest prevalences of RNA for DENV were 5.5% in Saudi Arabia (2015–16), 2.3% in Madeira, Portugal (2012–13), and 0.6% in Brazil (2012). The highest prevalences of RNA for ZIKV were 2.8% in French Polynesia (2013–14), 2.7% in Brazil (2015–16), and 1.8% in Martinique (2016). Overall seroprevalence, as assessed by IgG antibodies, was 21.6% for CHIKV, 24.0% for DENV, and 5.1% for ZIKV.DiscussionOur study shows a high proportion of donors who are viraemic and asymptomatic, especially during outbreaks, with prevalences surpassing 5% for DENV, 1% for CHIKV, and 2% for ZIKV. These data confirm a clear threat to blood transfusion safety. The elevated seroprevalence for these three arboviruses is also indicative of their wide circulation in populations, correlating with an increased risk of infected but asymptomatic donors. Health centres and institutions must address this threat, especially in tropical regions where the biggest outbreaks occur. 相似文献
56.
André São Pedro Renan Fernandes Cristiane Flora Villarreal Rosana Fialho Elaine Cabral Albuquerque 《Journal of microencapsulation》2016,33(1):18-29
Context Opioids have been used as the reference treatment on chronic pain. However, they are related to serious adverse effects which affect the patient compliance to treatment, as well as, his quality of life. Particulate formulations have been investigated as an alternative to improve opioid efficacy and safety. Objective Summarise the available studies concerning micro and nanoencapsulated opioid formulations discussing their biopharmaceutical characteristics, such as composition, size, in vitro release, pharmacokinetic and antinociceptive profile. Methods Papers available in 1995–2015 at Medline, Science Direct and Web of Science databases were collected and assessed. Searches were performed using varied combinations of the keywords of this work. Results Opioid-loaded particles showed prolonged drug release with maintenance of serum therapeutic concentrations and extended analgesia when compared with the free drugs. The side effects incidences were reduced or maintained the same. Conclusion Particulate formulations can significantly increase both potency and safety profiles of opioids. 相似文献
57.
Antonio Lpez-Uceda David Cantador-Fernndez Pedro Raposeiro Da Silva Jorge de Brito Jos María Fernndez-Rodríguez Jos Ramn Jimnez 《Materials》2022,15(15)
This study is framed within the circular economy model through the valorisation of industrial by-products. This research shows the results of producing self-compacting mortars (SCMs) with electric arc furnace dust (EAFD) and other industrial by-products such as fly ash, conforming (FA) or not conforming (NcFA), from coal-fired power plants, or recovery filler (RF) from hot-mix asphalt plants. Three batches of SCMs, each with one industrial-by product (FA, NcFA, or RF), and three levels of EAFD ratio incorporation (0%, 10%, 20%), were tested. An extra batch with a greater amount of FA was manufactured. When the incorporation ratio of EAFD rose, the mechanical strength decreased, due to the presence of a calcium zinc hydroxide dihydrate phase; nevertheless, this decrease diminished over time. All SCM mixes, except the 40C 40FA 20 EAFD mix, were above 20 MPa at 28 days. All mixes named 70C and 40C reached 40 and 30 MPa, respectively, at 90 days. Mixes with EAFD showed less capillarity and no difference in water absorption by immersion with respect to mixes without EAFD after 91 days. The SCMs designed proved to be stable in terms of leaching of the heavy metals contained in EAFD, where all the hardened SCMs were classified as inert. 相似文献
58.
Background: The association between vitamin D and weight gain remains controversial due to important limitations in the studies. We investigated the relationship between vitamin D levels and 5 and 10 years of weight and waist circumference change in a population-based prospective cohort study. Methods: Prospective study including participants aged between 35 and 75 years living in the city of Lausanne, Switzerland. Weight and waist change at 5- and 10-year follow-up were assessed according to baseline vitamin D status (normal, insufficiency and deficiency). Results: A total of 3638 participants (47.9 % women, mean age 51.6 ± 10.4 years) were included for the 5-year follow-up. No association was found between vitamin D categories and weight change, multivariate-adjusted average ± standard error: 1.6 ± 0.3, 1.5 ± 0.2 and 1.2 ± 0.1 kg for normal, insufficiency and deficiency, respectively, p = 0.159. For waist change, the corresponding values were 3.3 ± 0.4, 3.3 ± 0.2 and 3.4 ± 0.2 cm, p = 0.792. For the 10-year follow-up, data from 2999 participants (45.8% women, mean age 50.8 ± 10.3 years) were used. No association was found for weight 2.3 ± 0.4, 2.3 ± 0.2 and 2.0 ± 0.2 kg, p = 0.588, or for waist 3.7 ± 0.4, 3.6 ± 0.3 and 4.2 ± 0.2 cm for normal, insufficiency and deficiency, respectively, p = 0.259. Conclusion: No association between vitamin D status and weight or waist gain at 5- and 10-year follow-up was found. 相似文献
59.
60.
Robotic surgery is being used with increasing frequency in gynecologic oncology. To date, 44 cases were reported in the literature of radical hysterectomy performed with robotic surgery. When comparing robotic surgery with laparoscopy or laparotomy in performing a radical hysterectomy, the literature shows that robotic surgery offers an advantage over the other 2 surgical approaches with regard to operative time, blood loss, and length of hospitalization. Future studies are needed to further elucidate the equivalence or superiority of robotic surgery to laparoscopy or laparotomy in performing a radical hysterectomy. 相似文献