全文获取类型
收费全文 | 736056篇 |
免费 | 52127篇 |
国内免费 | 3077篇 |
专业分类
耳鼻咽喉 | 9491篇 |
儿科学 | 23716篇 |
妇产科学 | 17724篇 |
基础医学 | 112205篇 |
口腔科学 | 20448篇 |
临床医学 | 67328篇 |
内科学 | 136885篇 |
皮肤病学 | 16490篇 |
神经病学 | 49991篇 |
特种医学 | 27244篇 |
外国民族医学 | 76篇 |
外科学 | 107342篇 |
综合类 | 23054篇 |
现状与发展 | 15篇 |
一般理论 | 160篇 |
预防医学 | 55081篇 |
眼科学 | 16749篇 |
药学 | 57574篇 |
51篇 | |
中国医学 | 5711篇 |
肿瘤学 | 43925篇 |
出版年
2021年 | 6779篇 |
2019年 | 6102篇 |
2018年 | 8504篇 |
2017年 | 7009篇 |
2016年 | 7484篇 |
2015年 | 8795篇 |
2014年 | 11798篇 |
2013年 | 17346篇 |
2012年 | 23435篇 |
2011年 | 24438篇 |
2010年 | 15432篇 |
2009年 | 14341篇 |
2008年 | 22461篇 |
2007年 | 23740篇 |
2006年 | 23899篇 |
2005年 | 22048篇 |
2004年 | 21026篇 |
2003年 | 19852篇 |
2002年 | 19093篇 |
2001年 | 36949篇 |
2000年 | 37361篇 |
1999年 | 30508篇 |
1998年 | 7901篇 |
1997年 | 6687篇 |
1996年 | 6993篇 |
1995年 | 6642篇 |
1994年 | 6109篇 |
1992年 | 22974篇 |
1991年 | 22938篇 |
1990年 | 22318篇 |
1989年 | 22081篇 |
1988年 | 20037篇 |
1987年 | 19420篇 |
1986年 | 18470篇 |
1985年 | 17306篇 |
1984年 | 12702篇 |
1983年 | 10741篇 |
1982年 | 5922篇 |
1979年 | 11518篇 |
1978年 | 8128篇 |
1977年 | 6832篇 |
1976年 | 6594篇 |
1975年 | 7268篇 |
1974年 | 8498篇 |
1973年 | 8141篇 |
1972年 | 7658篇 |
1971年 | 7127篇 |
1970年 | 6877篇 |
1969年 | 6306篇 |
1968年 | 5780篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
中药生产过程质量控制关键技术研究进展 总被引:10,自引:8,他引:2
中医药发展已上升到国家战略层面,在医药行业贯彻实施"中国制造2025"战略的新形势下,中药生产过程质量控制是中药工业需要加快突破的关键领域之一。对中药生产过程质量控制领域在工艺设计、分析检测、过程建模、制造装备等方面的关键共性问题进行解析,综述了中药生产过程质量控制体系中工艺过程理解、生产过程实时分析方法开发、过程控制策略建立3个方面的研究进展;并结合企业研究实践,介绍了质量源于设计(quality by design,Qb D)、过程分析技术(process analytical technology,PAT)、实验设计(design of experiment,DOE)、多变量统计分析等关键技术在上述3个研究方向中的应用进展,分析了实际工业应用的难点问题并对其应用前景进行展望,旨在为中药企业应用和提升生产过程质量控制技术提供参考。 相似文献
2.
3.
动脉导管未闭(PDA)是早产儿常见疾病,目前早产儿PDA的自然发展过程仍未完全明确,PDA发生的有些高危因素仍存在争议,对PDA是否进行药物、手术干预,以及何时进行药物、手术干预仍存在争议。尽管已经有相当多的证据证实动脉导管持续开放可能有害,但目前尚缺乏关闭导管治疗方案的远期益处或害处的相关证据。大多数临床试验旨在评估短期导管开放对患儿的影响。目前尚无评估动脉导管持续开放对早产儿死亡率及并发症影响的临床试验。近年来PDA治疗上最大的变化是减少对PDA的治疗。该文重点总结胎龄28周早产儿PDA的治疗策略。 相似文献
4.
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
5.
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