全文获取类型
收费全文 | 31318篇 |
免费 | 3975篇 |
国内免费 | 340篇 |
专业分类
耳鼻咽喉 | 749篇 |
儿科学 | 508篇 |
妇产科学 | 547篇 |
基础医学 | 4005篇 |
口腔科学 | 542篇 |
临床医学 | 4742篇 |
内科学 | 6054篇 |
皮肤病学 | 1046篇 |
神经病学 | 2620篇 |
特种医学 | 1509篇 |
外科学 | 4325篇 |
综合类 | 444篇 |
现状与发展 | 2篇 |
一般理论 | 4篇 |
预防医学 | 2535篇 |
眼科学 | 587篇 |
药学 | 2293篇 |
1篇 | |
中国医学 | 396篇 |
肿瘤学 | 2724篇 |
出版年
2024年 | 74篇 |
2023年 | 550篇 |
2022年 | 502篇 |
2021年 | 1077篇 |
2020年 | 909篇 |
2019年 | 754篇 |
2018年 | 1242篇 |
2017年 | 1120篇 |
2016年 | 1403篇 |
2015年 | 1713篇 |
2014年 | 1856篇 |
2013年 | 2398篇 |
2012年 | 2403篇 |
2011年 | 2269篇 |
2010年 | 1625篇 |
2009年 | 1534篇 |
2008年 | 1701篇 |
2007年 | 1527篇 |
2006年 | 1480篇 |
2005年 | 1279篇 |
2004年 | 1093篇 |
2003年 | 933篇 |
2002年 | 813篇 |
2001年 | 602篇 |
2000年 | 509篇 |
1999年 | 483篇 |
1998年 | 424篇 |
1997年 | 404篇 |
1996年 | 418篇 |
1995年 | 340篇 |
1994年 | 250篇 |
1993年 | 182篇 |
1992年 | 183篇 |
1991年 | 180篇 |
1990年 | 149篇 |
1989年 | 161篇 |
1988年 | 143篇 |
1987年 | 120篇 |
1986年 | 98篇 |
1985年 | 103篇 |
1984年 | 81篇 |
1983年 | 83篇 |
1982年 | 56篇 |
1981年 | 63篇 |
1980年 | 43篇 |
1979年 | 48篇 |
1978年 | 31篇 |
1977年 | 30篇 |
1976年 | 29篇 |
1975年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Kara S. Tanaka MD Veronica R. Andaya BA Steven W. Thorpe MD Kenneth R. Gundle MD James B. Hayden MD Yee-Cheen Duong MD Raffi S. Avedian MD David G. Mohler MD Lee J. Morse MD Melissa N. Zimel MD Richard J. O'Donnell MD Andrew Fang MD Robert Lor Randall MD Tina H. Tran BS Christin New BA Rosanna L. Wustrack MD other members of Study Group FORCE 《Journal of surgical oncology》2023,127(1):148-158
2.
3.
Maxime Lafond Shin Yoshizawa Shin‐ichiro Umemura 《Journal of ultrasound in medicine》2019,38(3):567-580
Sonodynamic therapy (SDT) consists of the synergetic interaction between ultrasound and a chemical agent. In SDT, the cytotoxicity is triggered by ultrasonic stimuli, notably through cavitation. The unique features of SDT are relevant in the clinical context more than ever: the need for efficacy, accuracy, and safety while being noninvasive and preserving the patient's quality of life. However, despite the promising results of this technique, only a few clinical reports describe the use of SDT. The objective of this article is to provide an extensive overview of the clinical and preclinical research conducted in vivo on SDT, to identify the limitations, and to detail the developed strategies to overcome them. 相似文献
4.
5.
Cheong-Il Shin Sang Joon Park Ji-Hyun Kim Yeonyee Elizabeth Yoon Eun-Ah Park Bon-Kwon Koo Whal Lee 《Korean journal of radiology》2021,22(5):688
ObjectiveTo compare the lumen parameters measured by the location-adaptive threshold method (LATM), in which the inter- and intra-scan attenuation variabilities of coronary computed tomographic angiography (CCTA) were corrected, and the scan-adaptive threshold method (SATM), in which only the inter-scan variability was corrected, with the reference standard measurement by intravascular ultrasonography (IVUS).Materials and MethodsThe Hounsfield unit (HU) values of whole voxels and the centerline in each of the cross-sections of the 22 target coronary artery segments were obtained from 15 patients between March 2009 and June 2010, in addition to the corresponding voxel size. Lumen volume was calculated mathematically as the voxel volume multiplied by the number of voxels with HU within a given range, defined as the lumen for each method, and compared with the IVUS-derived reference standard. Subgroup analysis of the lumen area was performed to investigate the effect of lumen size on the studied methods. Bland-Altman plots were used to evaluate the agreement between the measurements.ResultsLumen volumes measured by SATM was significantly smaller than that measured by IVUS (mean difference, 14.6 mm3; 95% confidence interval [CI], 4.9–24.3 mm3); the lumen volumes measured by LATM and IVUS were not significantly different (mean difference, −0.7 mm3; 95% CI, −9.1–7.7 mm3). The lumen area measured by SATM was significantly smaller than that measured by LATM in the smaller lumen area group (mean of difference, 1.07 mm2; 95% CI, 0.89–1.25 mm2) but not in the larger lumen area group (mean of difference, −0.07 mm2; 95% CI, −0.22–0.08 mm2). In the smaller lumen group, the mean difference was lower in the Bland-Altman plot of IVUS and LATM (0.46 mm2; 95% CI, 0.27–0.65 mm2) than in that of IVUS and SATM (1.53 mm2; 95% CI, 1.27–1.79 mm2).ConclusionSATM underestimated the lumen parameters for computed lumen segmentation in CCTA, and this may be overcome by using LATM. 相似文献
6.
7.
目的 探讨在苯妥英钠(Phenytoin,PHT)促进大鼠牙周膜干细胞(Rat periodontal ligament stem cells,rPDLSCs)、大鼠骨髓间充质干细胞(Rat Bone Marrow Mesenchymal Stem Cells,rBMMSCs)黏附于牙骨质过程中,整合素α5β1(Integrin α5β1)起到的作用。方法 提取大鼠BMMSCs和PDLSCs,培养并纯化。通过细胞鉴定后,将获得的两种细胞各分为4组:40 mg/L PHT处理组、40 mg/L PHT+整合素α5抗体处理组、40 mg/L PHT+整合素β1抗体处理组、PBS处理组,每组细胞放入置有牙骨质片的96孔板处理4 h后,检测黏附于牙骨质片上的细胞量并做以比较。最后,利用qRT-PCR和Western blot检测40 mg/L PHT组与对照组细胞的整合素α5、β1亚基的mRNA与蛋白表达量。结果 40 mg/L PHT可促进rBMMSCs及rPDLSCs黏附于牙骨质片,加入整合素α5、β1抗体后,均明显抑制了40 mg/L PHT对rBMMSCs、rPDLSCs黏附于牙骨质的促进作用(P<0.01)。qRT-PCR、Western-blot结果显示PHT处理组的整合素α5、β1亚基表达量高于空白对照组(P<0.05)。结论 40 mg/L PHT能促进rBMMSCs、rPDLSCs黏附于牙骨质,该作用与整合素α5β1的表达上调密切相关。 相似文献
8.
9.
10.
Kota Sahara Rin Yamada Takashi Fujiwara Koichi Koizumi Shin‐ichiro Horiguchi Tsunekazu Hishima Tatsuro Yamaguchi 《Digestive endoscopy》2015,27(7):768-771
Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood ischemic colitis that occurs in the rectosigmoid colon of predominantly young, previously healthy, male patients. A 76‐year‐old Japanese man presented to our hospital with a 1‐year history of worsening diarrhea, lower abdominal pain, and weight loss (−6 kg). Laboratory evaluation revealed white blood cell count of 13 200/μL, C‐reactive protein level of 2.0 mg/dL (normal range, 0.0–0.3), and negative results for stool culture (including Clostridium difficile). Colonoscopy showed circumferential and edematous narrowing of the sigmoid colon with deep longitude ulceration. Biopsy was done and examination of the specimen demonstrated no specific ischemia. The patient was treated with bowel rest, antibiotics, and i.v. fluids; however, his symptoms worsened. Finally, sigmoidectomy was carried out. Histological examination demonstrated significant myointimal hyperplasia of mesenteric veins leading to thickening and stenosis of the venous lumen. Therefore, the final diagnosis was IMHMV. Three months following sigmoidectomy, he was asymptomatic. 相似文献