首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   7214篇
  免费   625篇
  国内免费   114篇
耳鼻咽喉   106篇
儿科学   1127篇
妇产科学   226篇
基础医学   1653篇
口腔科学   431篇
临床医学   352篇
内科学   1120篇
皮肤病学   113篇
神经病学   470篇
特种医学   327篇
外科学   970篇
综合类   394篇
现状与发展   2篇
预防医学   144篇
眼科学   79篇
药学   121篇
  2篇
中国医学   30篇
肿瘤学   286篇
  2024年   10篇
  2023年   135篇
  2022年   223篇
  2021年   306篇
  2020年   283篇
  2019年   332篇
  2018年   276篇
  2017年   269篇
  2016年   275篇
  2015年   244篇
  2014年   464篇
  2013年   434篇
  2012年   265篇
  2011年   363篇
  2010年   303篇
  2009年   316篇
  2008年   294篇
  2007年   289篇
  2006年   239篇
  2005年   233篇
  2004年   188篇
  2003年   172篇
  2002年   152篇
  2001年   150篇
  2000年   147篇
  1999年   126篇
  1998年   156篇
  1997年   126篇
  1996年   132篇
  1995年   95篇
  1994年   77篇
  1993年   103篇
  1992年   97篇
  1991年   80篇
  1990年   45篇
  1989年   49篇
  1988年   44篇
  1987年   44篇
  1986年   44篇
  1985年   57篇
  1984年   55篇
  1983年   41篇
  1982年   36篇
  1981年   44篇
  1980年   41篇
  1979年   25篇
  1978年   24篇
  1977年   20篇
  1976年   12篇
  1973年   6篇
排序方式: 共有7953条查询结果,搜索用时 328 毫秒
31.
用嗜银染色技术对34例良性胃溃疡、40例胃粘膜异型增生、46例胃腺癌组织石蜡切片中的核仁组成相关蛋白(AgNOR)进行研究,25例正常胃粘膜组织作对照。发现对照组、良性溃疡组,异型增生组和腺癌组的细胞核AgNOR平均计数差异有显著性(P<0.01)。恶性细胞中AgNOR的体积、形状及在细胞核内的位置也不相同。作者认为此法有助于区别胃的良性和恶性病变。  相似文献   
32.
Hip arthroplasty is a common orthopaedic procedure with proven long-term success and reliable results. A wide range of associated conditions may affect the outcome of the arthroplasty and the surgeon has to keep these in mind when planning the surgery. In this article, such situations are discussed and recommendations are drawn from the evidence available in literature.  相似文献   
33.
In acetabular dysplasia of the hip joint accompanied by a giant acetabular bone cyst, rotational acetabular osteotomy may cause serious complications, such as bone necrosis after surgery or fracture of the fragile acetabulum during the operation. In a patient with this condition, we performed a two-stage operation: first, autogenous bone grafting supplemented with hydroxyapatite filling, then rotational acetabular osteotomy (after new bone formation had been assured). Radiographs and CT scans showed favorable fusion of the grafted bone. Some 18 months after the second operation, arthrograms showed no inflow of contrast medium from the articular cavity into the bone cyst region, although this had been observed before treatment. Thus, an effective remodeling of bony congruency was indicated in the mobile acetabulum 5 years after the second operation. This two-stage operation appears to be useful for correcting acetabular dysplasia accompanied by a giant bone cyst and to carry a reduced risk of serious complications, such as deterioration of the articular surface of the acetabulum or necrosis of the translocated acetabulum.  相似文献   
34.
A newborn with rhizomelic bone dysplasia with club-like femora is reported. This is the fourth case Of this easily recognizable, recently reported, congenital bone disease. Maroteaux et al recently reported two patients with rhizomelic bone dysplasia and club-like femora as a distinctive new bone dysplasia. Their observation was confirmed by Gugliantini et al (2) who reported another case. This paper reports a fourth patient with this easily recognisable disorder.  相似文献   
35.
A second pregnancy of young, nonconsanguineous parents of Macedonian ethnic origin was examined by ultrasound. Polyhydramnios and hydrops fetalis were found as well as severe short limb, short stature, and cystic hygroma of the neck. An artificial abortion was performed at the age of 23 weeks. The radiological features included moth‐eaten severely shortened long bones and ectopic calcifications of long bones, vertebral column, ribs, pelvis, larynx, trachea. In addition, the fetus had large head with depressed nasal bridge, severe platyspondyly, and short barrel‐shaped trunk. Light microscopy demonstrated lack of chondrocyte columns and disorganization of the cartilaginous architecture. This is the seventh reported case of this rare form of lethal skeletal dysplasia. © 2002 Wiley‐Liss, Inc.  相似文献   
36.
We describe three cases of Wilms' tumour accompanied by central pericalyceal multicystic lesions closely resembling those seen in cystic nephroma. In continuity with these lesions or elsewhere in the kidney were areas of dysplastic renal tissue of the type sometimes referred to as intralobar nephroblastomatosis. A close homology of tissue differentiation was observed between the dysplastic lesions and the interstitial components of the cystic lesions. These findings support the hypothesis that, in some cases at least, cystic nephroma has more in common with the group of dysplastic lesions referred to as the nephroblastomatosis complex than with the true renal tumours of childhood.  相似文献   
37.
An alteration in cell/matrix interactions is one of the suggested mechanisms leading to cyst formation in polycystic kidney diseases. Most of these interactions are mediated by β1-integrins, a subfamily of integrin receptors, formed by the association of the β1-chain with different α-subunits. To date, no study on α-integrin subunit distribution during the early stages of cyst development has been reported. Using immunofluorescence, we analyzed the distribution of α-integrin subunits (α1, α2, α3, α5, and α6) and basement membrane proteins in kidneys of fetuses with autosomal dominant (ADPKD) or autosomal recessive polycystic kidney disease (ARPKD). The distribution was compared with that observed in normal fetal and post-natal kidneys, and in fetal cystic dysplasia and Meckel syndrome. Marked increase in α1-integrin staining was observed in normal and cystic collecting duct cells of both polycystic diseases (PKD), compared with normal and cystic controls. The distribution of integrin subunits α2, α3, and α6 was irregular in cyst epithelial cells of PKD and cystic controls. The increased expression of the α1-subunit specifically observed in PKD collecting duct cells may be an early consequence of the genetic defect in ARPKD. In ADPKD it parallels the reported expression of polycystin, the protein product of PKD1. The irregular expression of α2, α3, and α6 integrin subunits observed in all types of cysts suggests that cell/matrix interactions are altered early and may participate in the development of cysts, perhaps by contributing to the deregulation of cell survival in cystic diseases. Received May 28, 1996; received in revised form October 2, 1996; accepted October 25, 1996  相似文献   
38.
目的:探讨计算机图像分析技术对乳腺肿瘤核仁组成区相关嗜银蛋白(AgNORs)表达在病理学诊断中的意义。方法:选取乳癌、乳腺结构不良、乳腺纤维腺瘤及正常乳腺组织各20例,应用图像分析系统和嗜银染色技术,对乳腺病变组织的AgNORs进行形态计量学分析,观察每个细胞的胞核面积、核周长以及AgNOR颗粒数目、颗粒面积、AgNOR的大颗粒数、形态因子、面积比值、平均面积等8项参数。结果:正常乳腺及乳腺结构不良、乳腺纤维腺瘤组织的细胞核面积、核周长以及AgNOR颗粒数目、颗粒面积明显小于乳癌组织(P<0.01),AgNOR的大颗粒数、形态因子、面积比值、平均面积在乳癌组织与乳腺纤维腺瘤及正常乳腺组织间差异有统计学意义(P<0.05)。上述8项参数4组间多类判别分析回代符合率为72.5%,癌和非癌的判别回代符合率达100%。结论:图像分析对于乳腺良、恶性病变的鉴别诊断具有重要价值,是一精确、客观的AgNOR定量研究手段。  相似文献   
39.
本文对6例乳腺导管扩张症进行了临床病理报道,6例术前皆被误诊乳腺其他疾病,根据此种情况作了如何正确诊断的阐述.提出了常见误诊病例如何鉴别。  相似文献   
40.
We report herein the cases of two infants who developed right pneumonectomy syndrome, both of whom were born with gross C-type esophageal atresia (EA/TEF), and a hypoplastic right lung arising from the lower esophagus, being a bronchopulmonary foregut malformation (BPFM). Appropriate and well-timed treatments for a variety of sequelae primarily caused by the mediastinal shift must be considered after right pneumonectomy in early childhood.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号