全文获取类型
收费全文 | 725783篇 |
免费 | 50444篇 |
国内免费 | 1380篇 |
专业分类
耳鼻咽喉 | 9456篇 |
儿科学 | 23824篇 |
妇产科学 | 18034篇 |
基础医学 | 113203篇 |
口腔科学 | 20388篇 |
临床医学 | 65631篇 |
内科学 | 138959篇 |
皮肤病学 | 16372篇 |
神经病学 | 51318篇 |
特种医学 | 26339篇 |
外国民族医学 | 76篇 |
外科学 | 107659篇 |
综合类 | 15107篇 |
现状与发展 | 2篇 |
一般理论 | 173篇 |
预防医学 | 52905篇 |
眼科学 | 16843篇 |
药学 | 55027篇 |
3篇 | |
中国医学 | 2394篇 |
肿瘤学 | 43894篇 |
出版年
2021年 | 6159篇 |
2019年 | 6000篇 |
2018年 | 8542篇 |
2017年 | 6547篇 |
2016年 | 7279篇 |
2015年 | 8114篇 |
2014年 | 10986篇 |
2013年 | 16356篇 |
2012年 | 21892篇 |
2011年 | 22907篇 |
2010年 | 13497篇 |
2009年 | 12589篇 |
2008年 | 21156篇 |
2007年 | 22654篇 |
2006年 | 23030篇 |
2005年 | 21525篇 |
2004年 | 20981篇 |
2003年 | 19821篇 |
2002年 | 19325篇 |
2001年 | 36460篇 |
2000年 | 37015篇 |
1999年 | 30533篇 |
1998年 | 8051篇 |
1997年 | 6818篇 |
1996年 | 7102篇 |
1995年 | 6749篇 |
1994年 | 6209篇 |
1992年 | 23064篇 |
1991年 | 23022篇 |
1990年 | 22416篇 |
1989年 | 22158篇 |
1988年 | 20131篇 |
1987年 | 19519篇 |
1986年 | 18537篇 |
1985年 | 17397篇 |
1984年 | 12788篇 |
1983年 | 10834篇 |
1982年 | 6047篇 |
1979年 | 11589篇 |
1978年 | 8212篇 |
1977年 | 6903篇 |
1976年 | 6674篇 |
1975年 | 7328篇 |
1974年 | 8566篇 |
1973年 | 8197篇 |
1972年 | 7707篇 |
1971年 | 7154篇 |
1970年 | 6911篇 |
1969年 | 6338篇 |
1968年 | 5814篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
Stelter K. Theodoraki M. N. Becker S. Tsekmistrenko V. Olzowy B. Ledderose G. 《European archives of oto-rhino-laryngology》2015,272(3):639-639
European Archives of Oto-Rhino-Laryngology - 相似文献
4.
5.
Alexander Real Chierika Ukogu Divya Krishnamoorthy Nicole Zubizarreta Samuel K. Cho Andrew C. Hecht James C. Iatridis 《The spine journal》2019,19(2):225-231
Background Context
Low back pain (LBP) is a common complaint in clinical practice of multifactorial origin. Although obesity has been thought to contribute to LBP primarily by altering the distribution of mechanical loads on the spine, the additional contribution of obesity-related conditions such as diabetes mellitus (DM) to LBP has not been thoroughly examined.Purpose
To determine if there is a relationship between DM and LBP that is independent of body mass index (BMI) in a large cohort of adult survey participants.Study Design
Retrospective analysis of prospectively collected National Health and Nutrition Examination Survey (NHANES) data to characterize associations between LBP, DM, and BMI in adults subdivided into 6 subpopulations: normal weight (BMI 18.5–25), overweight (BMI 25–30), and obese (BMI >30) diabetics and nondiabetics. Diabetes was defined with glycohemoglobin A1c (HbA1c) ≥6.5%.Patient Sample
11,756 participants from NHANES cohort.Outcome Measures
Percentage of LBP reported.Methods
LBP reported in the 1999-2004 miscellaneous pain NHANES questionnaire was the dependent variable examined. Covariates included HbA1c, BMI, age, and family income ratio to poverty as continuous variables as well as race, gender, and smoking as binary variables. Individuals were further subdivided by weight class and diabetes status. Regression and graphical analyses were performed on the study population as a whole and also on subpopulations.Results
Increasing HbA1c did not increase the odds of reporting LBP in the full cohort. However, multivariate logistic regression of the 6 subpopulations revealed that the odds of LBP significantly increased with increasing HbA1c levels in normal weight diabetics. No other subpopulations reported significant relationships between LBP and HbA1c. LBP was also significantly associated with BMI for normal weight diabetics and also for obese subjects regardless of their DM status.Conclusions
LBP is significantly related to DM status, but this relationship is complex and may interact with BMI. These results support the concept that LBP may be improved in normal weight diabetic subjects with improved glycemic control and weight loss, and that all obese LBP subjects may benefit from improved weight loss alone. 相似文献6.
M. Iachina P.M. Ljungdalh R.G. Sørensen L. Kaerlev J. Blaakær O. Trosko N. Qvist B.M. Nørgård 《Clinical oncology (Royal College of Radiologists (Great Britain))》2019,31(2):115-123
Aims
To examine the influence of pre-existing psychiatric disorder on the choice of treatment in patients with gynaecological cancer.Materials and methods
The analyses were based on all patients who underwent surgical treatment for endometrial, ovarian or cervical cancer who were registered in the Danish Gynecological Cancer Database in the years 2007–2014 (3059 patients with ovarian cancer, 5100 patients with endometrial cancer and 1150 with cervical cancer). Logistic regression model and Cox regression model, adjusted for relevant confounders, were used to estimate the effect of pre-existing psychiatric disorder on the course of cancer treatment. Our outcomes were (i) presurgical oncological treatment, (ii) macroradical surgery for patients with ovarian cancer, (iii) radiation/chemotherapy within 30 days and 100 days after surgery and (iv) time from surgery to first oncological treatment.Results
In the group of patients with ovarian cancer, more patients with a psychiatric disorder received macroradical surgery versus patients without a psychiatric disorder, corresponding to an adjusted odds ratio of 1.24 (95% confidence interval 0.62–2.41) and the chance for having oncological treatment within 100 days was odds ratio = 1.26 (95% confidence interval 0.77–2.10). As for patients with endometrial cancer, all outcome estimates were close to unity. The adjusted odds ratio for oncological treatment within 30 days after surgery in patients with cervical cancer with a history of psychiatric disorder was 0.20 (95% confidence interval 0.03–1.54).Conclusions
We did not find any significant differences in the treatment of ovarian and endometrial cancer in patients with pre-existing psychiatric diagnoses. When it comes to oncological treatment, we suggest that increased attention should be paid to patients with cervical cancer having a pre-existing psychiatric diagnosis. 相似文献7.
8.
I. Fouzas C. Papanikolaou G. Katsanos N. Antoniadis N. Salveridis K. Karakasi S. Vasileiadou A. Fouza E. Mouloudi G. Imvrios V. Papanikolaou 《Transplantation proceedings》2019,51(2):416-420
Aims
Variations of the anatomy of donor hepatic arteries increase the number of arterial anastomoses during liver transplantation and, possibly, the incidence of hepatic artery thrombosis (HAT). In this study, we describe the arterial anatomic variations in liver grafts procured and transplanted by a single center in Greece, the techniques of arterial anastomosis, and their effect on the incidence of early HAT.Materials and Methods
From January 2013 to December 2017, the arterial anatomy of 116 grafts procured for liver transplantation were recorded, as well as the technique of arterial anastomosis and the incidence of early hepatic artery thrombosis (HAT <30 days).Results
A single hepatic artery was recorded in 72.41% of the procured grafts, an aberrant left hepatic artery (accessory or replaced) in 18 grafts (15.52%), and an aberrant right hepatic artery (accessory or replaced) in 17 grafts (14.66%), while other variations were observed in less than 1% of the procured livers. Of the 116 primary liver transplantations, 6 patients (5.17%) developed early HAT <30 days. Two of these patients (1.72%) had 1 anastomosis of the hepatic artery and 4 (3.45%) had 2 anastomoses due to anatomic variations.Conclusions
Anatomic variations of the hepatic artery in liver grafts is a common finding and increase the incidence of early HAT but not to a degree to make these grafts unusable. 相似文献9.
10.
N. V. Bashmakova G. N. Chistiakova I. A. Gazieva Y. M. Trapeznikova D. O. Mazurov 《Gynecological endocrinology》2015,31(10):31-33
AbstractThis study was undertaken to compare the concentrations of pro- and anti-angiogenic growth factors, nitric oxide (NO) stable metabolites in maternal serum and embryonic left ventricular (LV) isovolumic relaxation time (IRT, ms) during the first trimester in two groups of women: with pregnancy conceived by assisted reproductive technologies (ART, n?=?39) and normally conceived (control group, n?=?68) pregnancy. The concentration of vasoconstrictor endothelin 1 was 45.5 times more in ART than in control group. On the contrary, the concentrations of NO stable metabolites in ART were 1.9 times less than in control women. The assessment of angiogenic suppressors in ART women demonstrates the decrease in s-endoglin concentration was 1.6 times and in soluble receptor to vascular endothelial growth factor concentration was 2.0 times in comparison with control group. There was a significant increase in LV IRT in ART embryos in comparison to control ones. These data suggest significant changes in pro- anti-angiogenic factors balance and increase in vascular impedance in ART-conceived embryos. 相似文献