全文获取类型
收费全文 | 125877篇 |
免费 | 12178篇 |
国内免费 | 3695篇 |
专业分类
耳鼻咽喉 | 950篇 |
儿科学 | 1879篇 |
妇产科学 | 1571篇 |
基础医学 | 12899篇 |
口腔科学 | 3894篇 |
临床医学 | 13194篇 |
内科学 | 15121篇 |
皮肤病学 | 1516篇 |
神经病学 | 8035篇 |
特种医学 | 3535篇 |
外国民族医学 | 11篇 |
外科学 | 9695篇 |
综合类 | 18468篇 |
现状与发展 | 8篇 |
一般理论 | 3篇 |
预防医学 | 22174篇 |
眼科学 | 1373篇 |
药学 | 15946篇 |
125篇 | |
中国医学 | 5870篇 |
肿瘤学 | 5483篇 |
出版年
2024年 | 298篇 |
2023年 | 2296篇 |
2022年 | 3905篇 |
2021年 | 6326篇 |
2020年 | 6027篇 |
2019年 | 5128篇 |
2018年 | 4816篇 |
2017年 | 5082篇 |
2016年 | 5279篇 |
2015年 | 5098篇 |
2014年 | 9504篇 |
2013年 | 9837篇 |
2012年 | 8706篇 |
2011年 | 9193篇 |
2010年 | 6806篇 |
2009年 | 6264篇 |
2008年 | 5957篇 |
2007年 | 5853篇 |
2006年 | 4941篇 |
2005年 | 4271篇 |
2004年 | 3454篇 |
2003年 | 3099篇 |
2002年 | 2424篇 |
2001年 | 2288篇 |
2000年 | 1804篇 |
1999年 | 1506篇 |
1998年 | 1401篇 |
1997年 | 1303篇 |
1996年 | 970篇 |
1995年 | 990篇 |
1994年 | 947篇 |
1993年 | 738篇 |
1992年 | 698篇 |
1991年 | 593篇 |
1990年 | 506篇 |
1989年 | 504篇 |
1988年 | 442篇 |
1987年 | 377篇 |
1986年 | 291篇 |
1985年 | 385篇 |
1984年 | 299篇 |
1983年 | 179篇 |
1982年 | 205篇 |
1981年 | 157篇 |
1980年 | 155篇 |
1979年 | 116篇 |
1978年 | 76篇 |
1977年 | 54篇 |
1976年 | 73篇 |
1974年 | 41篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
71.
To evaluate the anthropometric indexes in subjects with varicocele compared to controls and the incidence of varicocele in different body mass index (BMI) groups for the purpose of exploring the association between varicocele and anthropometric indexes. A comprehensive literature search was conducted by using PubMed, MEDLINE, EMBASE databases and Cochrane Library up to February 2019. A systematic review and meta‐analysis was conducted by STATA, and Newcastle–Ottawa Scale was utilised for assessing risk of bias. Ultimately, 13 articles containing seven case–control studies and six cross‐sectional studies with 1,385,630 subjects were involved in our study. Pooled results demonstrated that varicocele patients had a lower BMI (WMD = ?0.77, 95% CI = ?1.03 to ?0.51) and a higher height than nonvaricocele participants, especially in grade 3 varicocele patients. Subgroup analyses showed that normal BMI individuals had a higher risk of varicocele than obese or overweight individuals and a lower risk than underweight individuals. In conclusion, this study indicates that varicocele patients have a lower BMI and a higher height than nonvaricocele participants. Moreover, men with excess bodyweight have a lower incidence of varicocele compared to normal weight or underweight people. That is to say, high BMI and adiposity protect against varicocele and high BMI is associated with a decreased risk of varicocele. 相似文献
72.
《Gaceta sanitaria / S.E.S.P.A.S》2022,36(4):376-379
ObjectiveTo estimate the prospective relationships between exposure to psychosocial risks dimensions included in the COPSOQ-Istas21 and the deterioration of general and mental health and sleep problems among workers residing in Spain.MethodCohort whose baseline corresponds to the 2016 Psychosocial Risks Survey with a new measurement after one year.ResultsSocial capital and interpersonal relations and leadership dimensions, as well as work?life conflict, were related to all health variables. Dimensions of work organization and job contents did it especially with the mental health, the quantitative demands with the general health and the emotional ones with the mental health. The dimensions related to job insecurity did not show relationships with health.ConclusionsThe results obtained reinforce the role of the COPSOQ-Istas21 as a useful instrument for the evaluation and prevention of psychosocial risks at work. 相似文献
73.
Factors predicting the development of pressure ulcers in an at‐risk population who receive standardized preventive care: secondary analyses of a multicentre randomised controlled trial 下载免费PDF全文
74.
Precise data on food chemical composition is crucial for any quantitative nutrition research and indispensable for evaluation and planning of computer-based menus. Moreover, exact food chemical composition is of the utmost importance in composing specific diets that may be low in certain essential nutrients. Therefore, this research evaluated a weekly vegan menu using three different food composition databases (FCDB): the Croatian, the official Danish Food Composition Database and the United States Department of Agriculture (USDA) – National Nutrient Database for Standard Reference. Significant differences (p < 0.05) were determined in evaluated and optimised offers for the same menu when using different FCDBs. Furthermore, in these menus quantities of some nutrients have not reached official daily recommendations needed for prevention of non-communicable diseases. In this research, new vegan menus that can provide adequate quantity of essential nutrients, regardless of FCDB utilized, were created with linear optimisation (LO). This resulted in high quality daily menu offers. However, depending on the FCDB that was used, optimal menus differed in daily meal combinations, and the effectiveness of the optimisation in the minimisation of differences caused by differences of data in FCDBs was tested. Linear optimisation has been proved to be an effective tool in planning of specific diets, such as vegan diets. Nonetheless, the quality of computer-planned menus depends heavily on the quality of FCDB used. 相似文献
75.
76.
Very preterm children are at increased risk of reduced processing speed at 5 years of age,predicted by typical complications of prematurity and prenatal smoking 下载免费PDF全文
77.
探讨高龄直肠癌患者腹会阴联合切除术(APR)后会阴切口并发症发生的相关危险因素。方法采用回顾性病例对照研究的方法,分析中国医学科学院肿瘤医院结直肠外科2007年1月至2018年9月行APR的72例高龄(≥80岁)直肠癌患者的临床病理资料。采用单因素和多因素分析确定影响高龄直肠癌患者APR后会阴切口并发症发生的危险因素。结果72例患者中,男47例,女25例,年龄为(81.8±1.8)岁。术后会阴切口并发症发生率为23.6%(17/72),其中切口感染5例,切口脂肪液化4例,切口延迟愈合8例。所有患者均顺利出院,无围手术期死亡病例。单因素分析显示,术前血清白蛋白<35 g/L、术中置入氟尿嘧啶缓释剂/洛铂冲洗液、盆底修复、糖尿病和冠心病与高龄患者APR术后会阴切口并发症的发生均有关(均P<0.05)。多因素分析显示,未行盆底修复(OR=0.17,95%CI为0.04~0.82;P=0.027)和糖尿病(OR=4.32,95%CI为1.05~17.81;P=0.043)为高龄直肠癌患者APR后会阴切口发生的独立危险因素。结论行APR的高龄直肠癌患者应尽可能保留盆底腹膜,并予以关闭。围手术期血糖监测也是预防会阴切口并发症发生的有力保障。 相似文献
78.
《Gaceta sanitaria / S.E.S.P.A.S》2016,30(3):208-214
ObjectiveTo measure incidence and main risk factors related to sexually transmitted infections (STIs) in Daroca Prison (Zaragoza, Spain).MethodA retrospective cohort study (2005-2013) to measure the incidence of STI and a cross-sectional study to measure risk factors.ResultsOf the 203 inmates, 79 developed an STI, 37 had a previous STI, 55.2% lacked knowledge on STI prevention, and 28.9% showed behaviours unfavourable for STI prevention. The incidence rate was 6.5 STIs per 1,000 inmates-year. The most frequent STIs were hepatitis B (39.7%), Ureaplasma urealyticum (19.1%), herpes simplex (16.2%) and HIV (8.8%). The risk (hazard ratio, HR) of acquiring a new STI was significantly higher in inmates with a history of previous STI (HR = 2.61; 95%CI: 1.01 to 6.69), and was at the limit of significance for non-preventive behaviour (HR = 2.10; 95%CI: 0.98 to 4.53), but not in knowledge related to STIs (HR = 1.33; 95%CI: 0.58 to 3.07).ConclusionThe most important risk factors in prison are behaviours related to STIs and previous history of STIs. Other factors are being a repeat offender, injecting drug use, or being in a methadone programme. Health personnel and peer education can facilitate prevention and control. 相似文献
79.
80.
《Vaccine》2022,40(28):3851-3860
We propose a probabilistic model to quantify the cost-benefit of mass Vaccination Scenarios (VSs) against COVID-19. Through this approach, we conduct a six-month simulation, from August 31st, 2021 to March 3rd, 2022, of nine VSs, i.e., the three primary vaccine brands in Brazil (CoronaVac, AstraZeneca and Pfizer), each with three different vaccination rates (2nd doses per week). Since each vaccine has different individual-level effectiveness, we measure the population-level benefit as the probability of reaching herd immunity (HI). We quantify and categorize the cost-benefit of VSs through risk graphs that show: (i) monetary cost vs. probability of reaching HI; and (ii) number of new deaths vs. probability of reaching HI. Results show that AstraZeneca has the best cost-benefit when prioritizing acquisition costs, while Pfizer is the most cost-beneficial when prioritizing the number of deaths. This work provides helpful information that can aid public health authorities in Brazil to better plan VSs. Furthermore, our approach is not restricted to Brazil, the COVID-19 pandemic, or the mentioned vaccine brands. Indeed, the method is flexible so that this study can be a valuable reference for future cost-benefit analyses in other countries and pandemics, especially in the early stages of vaccination, when data is scarce and uncertainty is high. 相似文献