全文获取类型
收费全文 | 152759篇 |
免费 | 7948篇 |
国内免费 | 226篇 |
专业分类
耳鼻咽喉 | 2665篇 |
儿科学 | 5551篇 |
妇产科学 | 3792篇 |
基础医学 | 21846篇 |
口腔科学 | 5024篇 |
临床医学 | 12577篇 |
内科学 | 28755篇 |
皮肤病学 | 4278篇 |
神经病学 | 15070篇 |
特种医学 | 6503篇 |
外科学 | 24342篇 |
综合类 | 843篇 |
一般理论 | 40篇 |
预防医学 | 8231篇 |
眼科学 | 3561篇 |
药学 | 10014篇 |
中国医学 | 249篇 |
肿瘤学 | 7592篇 |
出版年
2023年 | 921篇 |
2022年 | 699篇 |
2021年 | 1709篇 |
2020年 | 1472篇 |
2019年 | 1795篇 |
2018年 | 3424篇 |
2017年 | 2904篇 |
2016年 | 3849篇 |
2015年 | 3493篇 |
2014年 | 3876篇 |
2013年 | 6436篇 |
2012年 | 8218篇 |
2011年 | 9034篇 |
2010年 | 5145篇 |
2009年 | 3578篇 |
2008年 | 8953篇 |
2007年 | 9555篇 |
2006年 | 9184篇 |
2005年 | 9091篇 |
2004年 | 8510篇 |
2003年 | 8361篇 |
2002年 | 8185篇 |
2001年 | 5502篇 |
2000年 | 6884篇 |
1999年 | 3886篇 |
1998年 | 1570篇 |
1997年 | 1272篇 |
1996年 | 995篇 |
1995年 | 825篇 |
1994年 | 794篇 |
1993年 | 755篇 |
1992年 | 774篇 |
1991年 | 635篇 |
1990年 | 623篇 |
1989年 | 645篇 |
1988年 | 519篇 |
1987年 | 604篇 |
1986年 | 496篇 |
1985年 | 712篇 |
1984年 | 677篇 |
1983年 | 573篇 |
1982年 | 598篇 |
1981年 | 571篇 |
1980年 | 534篇 |
1979年 | 503篇 |
1978年 | 462篇 |
1977年 | 497篇 |
1976年 | 415篇 |
1975年 | 424篇 |
1974年 | 405篇 |
排序方式: 共有10000条查询结果,搜索用时 546 毫秒
1.
Michels Guido Horn Rudolf Helfen Andreas Hagendorff Andreas Jung Christian Hoffmann Beatrice Jaspers Natalie Kinkel Horst Greim Clemens-Alexander Knebel Fabian Bauersachs Johann Busch Hans-Jörg Kiefl Daniel Spiel Alexander O. Marx Gernot Dietrich Christoph F. 《Der Anaesthesist》2022,71(4):307-310
Die Anaesthesiologie - 相似文献
2.
Marike Gabrielson Mattias Hammarström Magnus Bäcklund Jenny Bergqvist Kristina Lång Ann H Rosendahl Signe Borgquist Roxanna Hellgren Kamila Czene Per Hall 《International journal of cancer. Journal international du cancer》2023,152(11):2362-2372
Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen. 相似文献
3.
Troppmair Teresa Egger J. Krösbacher A. Zanvettor A. Schinnerl A. Neumayr A. Baubin M. 《Der Anaesthesist》2022,71(4):272-280
Die Anaesthesiologie - Die Qualität eines Rettungssystems zeichnet sich auch durch den effizienten Einsatz seiner personellen und Fahrzeugressourcen aus. So können im berechtigten Fall... 相似文献
4.
5.
6.
Martin R. Späth Malte P. Bartram Nicolàs Palacio-Escat K. Johanna R. Hoyer Cedric Debes Fatih Demir Christina B. Schroeter Amrei M. Mandel Franziska Grundmann Giuliano Ciarimboli Andreas Beyer Jayachandran N. Kizhakkedathu Susanne Brodesser Heike Göbel Jan U. Becker Thomas Benzing Bernhard Schermer Martin Höhne Markus M. Rinschen 《Kidney international》2019,95(2):333-349
7.
Bela Anand-Apte Jennifer R. Chao Ruchira Singh Heidi Stöhr 《Journal of neuroscience research》2019,97(1):88-97
Sorsby fundus dystrophy (SFD), an autosomal dominant, fully penetrant, degenerative disease of the macula, is manifested by symptoms of night blindness or sudden loss of visual acuity, usually in the third to fourth decades of life due to choroidal neovascularization (CNV). SFD is caused by specific mutations in the Tissue Inhibitor of Metalloproteinase-3, (TIMP3) gene. The predominant histo-pathological feature in the eyes of patients with SFD are confluent 20–30 m thick, amorphous deposits found between the basement membrane of the retinal pigment epithelium (RPE) and the inner collagenous layer of Bruch's membrane. SFD is a rare disease but it has generated significant interest because it closely resembles the exudative or “wet” form of the more common age-related macular degeneration (AMD). In addition, in both SFD and AMD donor eyes, sub-retinal deposits have been shown to accumulate TIMP3 protein. Understanding the molecular functions of wild-type and mutant TIMP3 will provide significant insights into the patho-physiology of SFD and perhaps AMD. This review summarizes the current knowledge on TIMP3 and how mutations in TIMP3 cause SFD to provide insights into how we can study this disease going forward. Findings from these studies could have potential therapeutic implications for both SFD and AMD. 相似文献
8.
9.
Senem Maral Muradiye Acar Ozlem Sahin Balcik Eyyup Uctepe Omer Faruk Hatipoglu Derya Akdeniz Hatice Uludag Altun Ali Kosar Mehmet Gunduz Esra Gunduz 《Medicine》2015,94(16)
Chronic myeloproliferative disorders such as polycythemia vera (PV), essential thrombocytosis (ET), and idiopathic myelofibrosis arise from clonal proliferation of neoplastic stem cells in the bone marrow. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that have potential to degrade all types of extracellular matrix (ECM) and also play a role in remodeling of the ECM. It is known that MMPs play a role in bone marrow remodeling.The primary goal of our study is to explore the relationship between chronic myeloproliferative diseases and some of MMP gene polymorphisms. The demonstration of a relationship will help to understand whether these polymorphisms may be a potential early diagnosis marker of the diseases.Patients were selected from outpatient clinics of Turgut Ozal University Hospital, Ankara, Turkey, between December 2010 and May 2011. Twenty-eight patients that previously diagnosed and followed-up with PV, 17 with secondary polycythemia (SP), and 12 with ET were enrolled in the study, along with a control group of 22 healthy people.DNA was isolated from peripheral blood. Using polymerase chain reaction–restriction fragment length polymorphism method, MMP2 and MMP9 gene polymorphisms were analyzed with agarose gel electrophoresis. There was a statistically significant difference between the study groups and the control group in terms of Gln279Arg polymorphisms rates of MMP9. The highest MMP9 Gln279Arg polymorphism rate was observed in the ET group. But nobody from the control group had polymorphic MMP9. There was no statistically significant difference between the groups in terms of MMP2-735 C > T polymorphism rates.In conclusion, MMP9 gene Gln279Arg polymorphism was associated with ET, SP, and PV diseases. Hence, we believe that these gene polymorphisms may play a role in the mechanism of bone marrow fibrosis and may be a factor that increases the risk of thrombosis. Illumination of the molecular basis of the relationship between MMP-thrombosis and MMP-fibrosis provides a better understanding of the pathophysiology of PV and ET diseases and will allow new approaches to diagnosis and treatment. 相似文献