全文获取类型
收费全文 | 25337篇 |
免费 | 1678篇 |
国内免费 | 850篇 |
专业分类
耳鼻咽喉 | 282篇 |
儿科学 | 171篇 |
妇产科学 | 180篇 |
基础医学 | 5404篇 |
口腔科学 | 2461篇 |
临床医学 | 1599篇 |
内科学 | 3471篇 |
皮肤病学 | 383篇 |
神经病学 | 1126篇 |
特种医学 | 1020篇 |
外科学 | 2331篇 |
综合类 | 3257篇 |
现状与发展 | 4篇 |
一般理论 | 1篇 |
预防医学 | 1010篇 |
眼科学 | 1291篇 |
药学 | 2189篇 |
15篇 | |
中国医学 | 1074篇 |
肿瘤学 | 596篇 |
出版年
2024年 | 77篇 |
2023年 | 418篇 |
2022年 | 1109篇 |
2021年 | 1331篇 |
2020年 | 988篇 |
2019年 | 864篇 |
2018年 | 791篇 |
2017年 | 774篇 |
2016年 | 757篇 |
2015年 | 827篇 |
2014年 | 1402篇 |
2013年 | 1588篇 |
2012年 | 1109篇 |
2011年 | 1336篇 |
2010年 | 1069篇 |
2009年 | 1025篇 |
2008年 | 1042篇 |
2007年 | 1175篇 |
2006年 | 981篇 |
2005年 | 1006篇 |
2004年 | 876篇 |
2003年 | 826篇 |
2002年 | 693篇 |
2001年 | 582篇 |
2000年 | 505篇 |
1999年 | 464篇 |
1998年 | 443篇 |
1997年 | 391篇 |
1996年 | 302篇 |
1995年 | 278篇 |
1994年 | 265篇 |
1993年 | 232篇 |
1992年 | 238篇 |
1991年 | 209篇 |
1990年 | 197篇 |
1989年 | 165篇 |
1988年 | 181篇 |
1987年 | 157篇 |
1986年 | 162篇 |
1985年 | 208篇 |
1984年 | 153篇 |
1983年 | 122篇 |
1982年 | 144篇 |
1981年 | 93篇 |
1980年 | 84篇 |
1979年 | 58篇 |
1978年 | 42篇 |
1977年 | 51篇 |
1976年 | 27篇 |
1975年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
James Guest 《ANZ journal of surgery》1997,67(8):524-527
William Cheselden (1688–1752) as a young man had a considerable reputation as an anatomist. He was one of the first to give a regular series of lecture/demonstrations and he incorporated this material into a basic text The Anatomy of the Humane Body, which was extremely popular and was in print for 100 years. He was even better known as a surgeon, being on the staff of three teaching hospitals and recognized as the most skilful lithotomist of his time. His achievements are on record and he must be regarded as one of the greatest of British surgeons. Perhaps his greatest impact was his strong advocacy for the separation of surgeons from the Barber-Surgeons' Company. He realised how much this long-established relationship was delaying the advancement of surgeons and surgery, and his vigorous action resulted in an Act of Parliament that severed the old ties and established in 1745 the Corporation of Surgeons, forerunner of the Royal College of Surgeons of England. 相似文献
32.
扩大经蝶入路进入海绵窦内侧腔的应用显微解剖 总被引:1,自引:0,他引:1
目的为临床开展扩大经蝶入路进入海绵窦内侧腔手术提供解剖学依据。方法用50例成人头颅标本.在显微镜下对蝶窦外侧壁、蝶鞍、海绵窦及周围结构进行解剖学观察并测量。模拟扩大经蝶入路磨除海绵窦腹侧骨质,切开海绵窦内侧壁,显露海绵窦内侧腔。结果颈内动脉(ICA)明显隆起于蝶窦侧壁的占58%,蝶窦内隆起呈管型占3%。鞍底硬膜分为2层,海绵窦内侧壁的上部南垂体硬膜构成,无骨性结构支撑;下部由骨周硬膜构成,有蝶窦侧壁骨质支撑。两侧海绵窦内侧壁的距离为(14.8±2.7)mm。海绵窦内侧腔位于C4段ICA与垂体之间,腔内为丰富的静脉丛,最宽可达7mm,但常因ICA扭曲而闭塞。无颅神经穿越海绵窦内侧腔,ICA是扩大经蝶入路探查海绵窦遇到的第一个主要结构。结论扩大经蝶入路进入海绵窦内侧腔是安全可行的。 相似文献
33.
用聚乙烯醇(PVA)的二甲基亚砜(DMSO)溶液对水热反应法合成的超细羟基磷灰石(HAP)进行表面改性,用溶液分散复合法分别制备了HAP含量均为0.03g/mE的聚乳酸(PLLA)/HAP和PLIA/HAP-PVA复合物,并经过挤出成型得到φ=5mm的棒材。重点研究了热拉伸取向的拉伸规律及表面改性前后HAP粒子在PLLA基质中的分散情况。结果表明,经PVA改性的HAP粒子在PLLA基质中的分散要明显优于未经改性的HAP粒子。拉伸取向后PLLA/HAP-PVA复合材料的弯曲强度达262MPa。 相似文献
34.
Paul P. Dillon Stephen J. Daly John G. Browne Bernadette M. Manning Elma Loomans Aart Van Amerongen Richard O'Kennedy 《Food and Agricultural Immunology》2003,15(3):225-234
Public concern surrounding antibiotic contamination in food and food products has made it imperative to develop analytical methods for their detection. Polyclonal antibodies were used in the development of a surface plasmon resonance (SPR)-based inhibition immunoassay for cephalexin. A conjugate consisting of cephalexin-bovine serum albumin (BSA) was immobilized on the dextran gel surface of the sensor chip. Binding/regeneration studies of antibody to immobilized cephalexin were studied and dissociation of the antibody from the immobilized cephalexin was easily achieved with 10 mmol l-1 NaOH. Forty surface regeneration cycles were carried out and found to be reproducible with only a 7.4% decrease in binding over this number of regenerations. Model inhibition immunoassays for cephalexin were developed in PBS and spiked milk samples with detection ranges of 4.88 to 2,500 ng ml-1 and 244 to 3,906 pg ml-1, respectively. 相似文献
35.
颅面部的 CT扫描检查主要包括颅脑面部上、下颌骨、中耳、内耳、鼻窦、眼眍、眼球及颞骨茎突等部位的扫描检查 ,上述部位的扫描检查的位置的摆法 ,层面的厚度、间距 ,扫描时间及螺距等参数的选择及扫描后图像的后处理工作对检查结果的诊断至关重要。上述参数任意一个选择不当及 相似文献
36.
Functional anatomy and biomechanics of the meniscus 总被引:2,自引:0,他引:2
George L. Caldwell Jr. MD Answorth A. Allen MD Freddie H. Fu MD 《Operative Techniques in Sports Medicine》1994,2(3):152-163
The meniscus is no longer considered the evolutionary remnant in the knee joint.Rather, it is now well established as an important structure that is integral to the complex biomechanics and proper functioning of the knee. The medial and lateral menisci form two crescent-shaped wedges of fibrocartilage between the femoral condyles and tibial plateaus.The knee joint biomechanics are based on a complex interaction of these intra-articular structures. The functions ascribed to the menisci include load transmission, shock absorption, stability, proprioception, joint lubrication, and joint nutrition. Load transmission generally is accepted as one of its primary functions. The menisci transmit a portion of the axial forces across the knee joint by converting this load into “hoop stresses.” This is accomplished by their unique shape, composition, and anatomic attachments. The menisci are relatively mobile structures and their motion during knee flexion also is determined by their shape and soft tissue attachments/constraints. Preservation of the meniscal functions is essential, and the authors review the basic anatomic and biomechanical concepts necessary to understand techniques for repair and restoration of these functions. 相似文献
37.
人抗HBsAg噬菌体抗体Fab段基因的序列分析及表达 总被引:3,自引:0,他引:3
对已建的噬菌体抗体库分离出来的人抗-HBs克隆进行了序列分析和表达研究,发现4个克隆中3个克隆的重链和轻链完全相同,DNA序列分析表明VH分别属于VH1亚群和Ⅱ亚群,其轻链VL分别属于VλⅡ亚群和VλⅠ亚群。构建了可溶性Fab段表达载体,显示出在细菌中表达的Fab段抗体与HBsAg特异性结合,这说明所筛选出来的噬菌体抗体具有HBdisplay status 相似文献
38.
Based upon detailed dissections of the lymphatic system in adult cadavers, the lymphatic drainage of the gallbladder was divided
into three pathways: (1) The cholecystoretropancreatic pathway, which had two routes, one running spirally from the anterior
surface of the common bile duct to the right rear, and the other running almost straight down from the posterior surface of
the common bile duct. These routes converged at the principal retroportal node at the posterior surface of the head of the
pancreas. (2) The cholecysto-celiac pathway; this was the route running to the left through the hepatoduodenal ligament to
reach the celiac nodes. (3) The cholecysto-mesenteric pathway; this was the route running to the left in front of the portal
vein to connect with the nodes at the superior mesenteric root. The cholecysto-retropancreatic pathway can be regarded as
the main pathway, and the principal retroportal node appeared to be critical as the main terminal node in the visceral lymphatic
system of the gallbladder. These three pathways converged with the abdomino-aortic lymph nodes near the left renal vein, and
the nodes in the interaortico-caval space were considered to be of particular importance.
Offprint requests to: M. Ito 相似文献
39.
40.
垂体高度的断层解剖及MRI测量 总被引:3,自引:0,他引:3
目的:通过尸体断层标本和MRI对照测量垂体的高度,为垂体的影像学诊断提供诊断标准、材料和方法:利用35例成人尸体断层标本,在各个断面上测量垂体的高度;在103例成人冠状头颅MRI上测量垂体的高度,并按年龄和性别分为十二组。将断层标本和MRI的测量数据进行比较。结果:在断层标本上测量垂体的平均高度为5.3±0.6(4.0-7.6)mm;MRI上的平均高度为5.4±1.3(4.0-8.3)mm。两组数据比较,无显著性差异(P>0.05)。男性垂体的平均高度为5.3±1.2(4.0-7.2)mm,女性垂体的平均高度为5.5±1.4(4.0-8.3)mm。女性垂体的平均高度大于男性。各年龄组比较显示,20岁以后,随年龄增长,垂体高度逐渐下降。结论:在MRI诊断中,垂体高度女性≥9mm,男性≥8mm可考虑垂体异常。垂体高度女性大于男性;20岁以后,随年龄增长,垂体高度有逐渐下降的趋势。 相似文献