全文获取类型
收费全文 | 3789542篇 |
免费 | 273095篇 |
国内免费 | 9864篇 |
专业分类
耳鼻咽喉 | 51854篇 |
儿科学 | 125173篇 |
妇产科学 | 104687篇 |
基础医学 | 538485篇 |
口腔科学 | 106006篇 |
临床医学 | 349010篇 |
内科学 | 734841篇 |
皮肤病学 | 89392篇 |
神经病学 | 306452篇 |
特种医学 | 143461篇 |
外国民族医学 | 1170篇 |
外科学 | 564319篇 |
综合类 | 82848篇 |
现状与发展 | 8篇 |
一般理论 | 1436篇 |
预防医学 | 295635篇 |
眼科学 | 87234篇 |
药学 | 276639篇 |
9篇 | |
中国医学 | 8630篇 |
肿瘤学 | 205212篇 |
出版年
2019年 | 30028篇 |
2018年 | 42072篇 |
2017年 | 32236篇 |
2016年 | 37052篇 |
2015年 | 41661篇 |
2014年 | 57949篇 |
2013年 | 87340篇 |
2012年 | 116239篇 |
2011年 | 123526篇 |
2010年 | 73945篇 |
2009年 | 70340篇 |
2008年 | 114767篇 |
2007年 | 122041篇 |
2006年 | 123878篇 |
2005年 | 119116篇 |
2004年 | 114555篇 |
2003年 | 110270篇 |
2002年 | 106694篇 |
2001年 | 179698篇 |
2000年 | 184241篇 |
1999年 | 154993篇 |
1998年 | 45070篇 |
1997年 | 39813篇 |
1996年 | 39770篇 |
1995年 | 38388篇 |
1994年 | 35141篇 |
1993年 | 32912篇 |
1992年 | 120542篇 |
1991年 | 116563篇 |
1990年 | 113264篇 |
1989年 | 109473篇 |
1988年 | 100422篇 |
1987年 | 98427篇 |
1986年 | 92453篇 |
1985年 | 88483篇 |
1984年 | 66321篇 |
1983年 | 56380篇 |
1982年 | 33450篇 |
1981年 | 29868篇 |
1979年 | 59329篇 |
1978年 | 42013篇 |
1977年 | 35573篇 |
1976年 | 33306篇 |
1975年 | 35376篇 |
1974年 | 42109篇 |
1973年 | 40304篇 |
1972年 | 37906篇 |
1971年 | 35118篇 |
1970年 | 32884篇 |
1969年 | 31069篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
61.
Chronic transplant dysfunction is a complex dynamic pathogenic process. Clinically, a decrease in glomerular filtration rate (GFR) becomes apparent leading to chronic renal insufficiency and dialysis or death from cardiovascular events. Chronic transplant dysfunction can develop into a chronic alIograft nephropathy (CAN) as a specific entity with dynamic progression. CAN includes a collection of immunologic and non-immunologic factors, rejection, ischemia time, donor and recipient characteristics and toxicity of calcineurin inhibitors. Despite improvements in immunosuppression, the long-range prognosis of renal allografts has not improved. Whether modern immunosuppressive concepts with reduction or avoidance of calcineurin inhibitors and a therapy based on antimetabolites, such as mycophenolate or mTOR-inhibitors could lead to a prolongation of transplant survival, remains to be seen. 相似文献
62.
Heather M Arthur Christine Patterson James A Stone 《European journal of cardiovascular prevention and rehabilitation》2006,13(1):3-9
BACKGROUND: Presently, complementary and alternative medicine, including both therapies and herbal/oral supplements, is used globally. Few studies have examined the use of specific therapies, separate from herbal/oral supplements, in cardiac rehabilitation. This paper presents a systematic evaluation of current research evidence related to use of specific complementary and alternative medicine therapies in secondary prevention of cardiovascular disease, with a view to making recommendations for cardiac rehabilitation. DESIGN AND METHODS: A literature search was conducted using complementary and alternative medicine websites, Medline, Allied and Complementary Medicine, CINAHL, Cochrane databases, EMBASE, SportDiscus, Clinical Evidence, and Evidence-Based Practice to locate research-based scientific evidence related to the use of complementary and alternative medicine in cardiac rehabilitation. Search keywords included heart, cardiac, cardiovascular, coronary, myocardial and rehabilitation, combined with particular therapies. Herbal/oral supplements were not included in this evaluation. RESULTS: Some complementary and alternative medicine therapies may be useful to patients by themselves or coupled with traditional cardiac rehabilitation. Tai chi, as a complement to existing exercise interventions, can be utilized for low and intermediate risk patients. transcendental meditation may be used as a stress reduction technique. There was insufficient evidence found for the use of acupuncture or chelation therapy in cardiac rehabilitation or secondary prevention. CONCLUSIONS: Some complementary and alternative medicine therapies hold promise for patients in cardiac rehabilitation. Further research is essential, however, in all areas of complementary and alternative medicine to confirm its usefulness as an adjunct to cardiac rehabilitation. 相似文献
63.
Laparoscopic surgery has several advantages over traditional surgery because it has been shown to be less invasive. The next logical step in the evolution of minimally invasive surgery may be to eliminate all abdominal incisions. The natural orifices provide a port of entry via the gastrointestinal tract to the peritoneal cavity. This approach would require the creation of a perforation, which is considered to be a major complication of endoscopy with significant morbidity and mortality. However, there are several recent studies that have described the technical feasibility and safety of a per‐oral transgastric approach to the peritoneal cavity using conventional endoscopes. Theoretically, this approach could reduce postoperative abdominal wall pain, wound infection, hernia formation, and adhesions. This article aims to summarize the current status of transgastric surgery, currently referred to as natural orifice transluminal endoscopic surgery (NOTES), and to address some of its future challenges. 相似文献
64.
N. SUVAJD
I V. EMERIKI‐MARTINOVI . ARANOVI M. PETROVI M. POPOVI V. ARTIKO M. UPI I. ELEZOVI 《International journal of laboratory hematology》2006,28(5):317-320
We report the case of a littoral‐cell angioma of the spleen, a recently described benign vascular tumour, whose imaging and pathological characteristics have been discussed only by a few authors. The diagnosis was made after elective splenectomy. The CT images, scintigraphy and histological specimens are presented, and differential diagnoses discussed. 相似文献
65.
66.
67.
68.
G Steinitz M C Martín N Gazit-Yaari M L Quesada J de la Nuez R Casillas U Malik Z B Begin 《Applied radiation and isotopes》2006,64(4):520-524
Multi-day signals, generally with duration of 2-10 days, are a prominent temporal variation type of radon (Rn) in geogas in the unsaturated zone. Rare multi-day Rn signals have been found which are characterized by: (a) a declining limb lasting up to 10 days which conforms to the radioactive decay of Rn, (b) recurs at the same location and (c) is recorded in diverse situations-volcanic and seismogenic. It suggested that a Rn blob is injected at a lower level on a steady upward flow of geogas whereby the rise and final fall of the signal are attributed to the edges of the blob while the central Rn-decay segment records the passing of the decaying blob itself. Rn-decay signals are a small subset of multi-day Rn signals which are considered as highly irregular and unusable for the understanding of geophysical processes. In difference, it is concluded that multi-day Rn signals are probably proxies of subtle geodynamic processes at upper crustal levels and are therefore significant for studying such processes. 相似文献
69.
70.
Glauber T Silva Alejandro C Frery Mostafa Fatemi 《Computerized medical imaging and graphics》2006,30(5):321-327
We study the image formation of vibro-acoustography systems based on a concave sector array transducer taking into account depth-of-field effects. The system point-spread function (PSF) is defined in terms of the acoustic emission of a point-target in response to the dynamic radiation stress of ultrasound. The PSF on the focal plane and the axis of the transducer are presented. To extend the obtained PSF to the 3D-space, we assume it is a separable function in the axial direction and the focal plane of the transducer. In this model, an image is formed through the 3D convolution of the PSF with an object function. Experimental vibro-acoustography images of a breast phantom with lesion-like inclusions were compared with simulated images. Results show that the experimental images are in good agreement with the proposed model. 相似文献