全文获取类型
收费全文 | 72455篇 |
免费 | 5190篇 |
国内免费 | 265篇 |
专业分类
耳鼻咽喉 | 859篇 |
儿科学 | 1843篇 |
妇产科学 | 1301篇 |
基础医学 | 9055篇 |
口腔科学 | 1110篇 |
临床医学 | 7237篇 |
内科学 | 15104篇 |
皮肤病学 | 916篇 |
神经病学 | 6854篇 |
特种医学 | 2454篇 |
外国民族医学 | 4篇 |
外科学 | 12492篇 |
综合类 | 1002篇 |
现状与发展 | 1篇 |
一般理论 | 87篇 |
预防医学 | 6217篇 |
眼科学 | 1482篇 |
药学 | 4548篇 |
中国医学 | 76篇 |
肿瘤学 | 5268篇 |
出版年
2023年 | 365篇 |
2022年 | 784篇 |
2021年 | 1799篇 |
2020年 | 957篇 |
2019年 | 1555篇 |
2018年 | 1869篇 |
2017年 | 1253篇 |
2016年 | 1384篇 |
2015年 | 1554篇 |
2014年 | 2421篇 |
2013年 | 3271篇 |
2012年 | 4916篇 |
2011年 | 5227篇 |
2010年 | 2868篇 |
2009年 | 2578篇 |
2008年 | 4451篇 |
2007年 | 4579篇 |
2006年 | 4418篇 |
2005年 | 4411篇 |
2004年 | 4255篇 |
2003年 | 3880篇 |
2002年 | 3686篇 |
2001年 | 554篇 |
2000年 | 433篇 |
1999年 | 649篇 |
1998年 | 803篇 |
1997年 | 683篇 |
1996年 | 610篇 |
1995年 | 563篇 |
1994年 | 508篇 |
1993年 | 478篇 |
1992年 | 400篇 |
1991年 | 408篇 |
1990年 | 341篇 |
1989年 | 343篇 |
1988年 | 316篇 |
1987年 | 311篇 |
1986年 | 296篇 |
1985年 | 339篇 |
1984年 | 500篇 |
1983年 | 414篇 |
1982年 | 548篇 |
1981年 | 534篇 |
1980年 | 516篇 |
1979年 | 283篇 |
1978年 | 311篇 |
1977年 | 292篇 |
1976年 | 237篇 |
1975年 | 233篇 |
1974年 | 244篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Qian Zhang Larry D. Mesner Gina M. Calabrese Naomi Dirckx Zhu Li Angela Verardo Qian Yang Robert J. Tower Marie-Claude Faugere Charles R. Farber Thomas L. Clemens 《The Journal of clinical investigation》2021,131(7)
Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass. 相似文献
2.
3.
4.
5.
6.
7.
Anuj Shrestha Zeeshan Jawa Kathryn L. Koch Amy B. Rankin Qun Xiang Anand Padmanabhan Matthew S. Karafin Joshua J. Field 《Journal of clinical apheresis》2015,30(6):353-358
Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
8.
Michelle E. Wilson Charles Kim Jacqueline Carrasco 《Orbit (Amsterdam, Netherlands)》2016,35(5):288-291
A 48-year-old smoker with a history of hyperthyroidism treated 10 years prior to presentation with radioactive iodine ablation of the thyroid gland presented to his ophthalmologist with a 2-week history of transient loss of vision in the right eye occurring for 1 to 2 hours each morning. He denied ocular pain, diplopia or change in the prominence of one or both eyes. Examination revealed 2 mm of relative proptosis on the right, bilateral temporal flare and lower lid retraction. There was minimal upper lid retraction and no evidence of lid lag. Ocular motility was full. Dilated fundoscopic examination revealed bilateral optic nerve edema, right more than left. CT of the orbit demonstrated enlargement of the extraocular muscles bilaterally with marked enlargement of the right medial rectus and left inferior rectus muscles resulting in crowding at the orbital apex bilaterally. Laboratory testing revealed the patient to be hyperthyroid. The patient was treated with high dose oral steroids followed by orbital radiation. Hyperthyroidism was managed by the patient’s primary care physician. Visual symptoms rapidly improved with oral steroids and orbital radiation. Optic nerve edema completely resolved. Repeat CT imaging demonstrated a reduction in the enlargement of the extraocular muscles with relief of bilateral optic nerve compression. 相似文献
9.
Michael E Egger Joanna M Ohlendorf Charles R Scoggins Kelly M McMasters Robert C G Martin II 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2015,17(9):839-845
BackgroundThe aim of this paper is to assess the current state of quality and outcomes measures being reported for hepatic resections in the recent literature.MethodsMedline and PubMed databases were searched for English language articles published between 1 January 2002 and 30 April 2013. Two examiners reviewed each article and relevant citations for appropriateness of inclusion, which excluded papers of liver donor hepatic resections, repeat hepatectomies or meta-analyses. Data were extracted and summarized by two examiners for analysis.ResultsFifty-five studies were identified with suitable reporting to assess peri-operative mortality in hepatic resections. In only 35% (19/55) of the studies was the follow-up time explicitly stated, and in 47% (26/55) of studies peri-operative mortality was limited to in-hospital or 30 days. The time period in which complications were captured was not explicitly stated in 19 out of 28 studies. The remaining studies only captured complications within 30 days of the index operation (8/28). There was a paucity of quality literature addressing truly patient-centred outcomes.ConclusionQuality outcomes after a hepatic resection are inconsistently reported in the literature. Quality outcome studies for a hepatectomy should report mortality and morbidity at a minimum of 90 days after surgery. 相似文献
10.