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   1067篇
  免费   75篇
  国内免费   8篇
耳鼻咽喉   4篇
儿科学   87篇
妇产科学   8篇
基础医学   114篇
口腔科学   29篇
临床医学   169篇
内科学   208篇
皮肤病学   14篇
神经病学   33篇
特种医学   284篇
外科学   56篇
综合类   24篇
预防医学   42篇
眼科学   7篇
药学   35篇
中国医学   5篇
肿瘤学   31篇
  2024年   3篇
  2023年   8篇
  2022年   4篇
  2021年   13篇
  2020年   9篇
  2019年   8篇
  2018年   22篇
  2017年   11篇
  2016年   19篇
  2015年   21篇
  2014年   28篇
  2013年   26篇
  2012年   20篇
  2011年   21篇
  2010年   36篇
  2009年   57篇
  2008年   34篇
  2007年   10篇
  2006年   17篇
  2005年   6篇
  2004年   10篇
  2003年   17篇
  2002年   12篇
  2001年   18篇
  2000年   13篇
  1999年   18篇
  1998年   51篇
  1997年   59篇
  1996年   66篇
  1995年   52篇
  1994年   50篇
  1993年   53篇
  1992年   25篇
  1991年   14篇
  1990年   16篇
  1989年   42篇
  1988年   33篇
  1987年   34篇
  1986年   38篇
  1985年   30篇
  1984年   21篇
  1983年   12篇
  1982年   22篇
  1981年   14篇
  1980年   9篇
  1979年   4篇
  1978年   4篇
  1977年   12篇
  1976年   11篇
  1975年   13篇
排序方式: 共有1150条查询结果,搜索用时 0 毫秒
31.
HotSpots     
  相似文献   
32.
We have recently shown using dansyl-L-lysine exclusion studies that the release of human chorionic gonadotrophin (HCG) in conjunction with L- lactate dehydrogenase (LDH) from first trimester villi during organ culture is symptomatic of syncytiotrophoblast degeneration. The purpose of this study was to examine chorionic villi at the ultrastructural level in order to determine events occurring during organ culture. The tissue was sampled after 0, 24, 48 and 120 h in culture and processed for electron microscopy. In addition to confirming the previously recorded syncytial degeneration, the electron micrographs showed clearly the generation of a new syncytiotrophoblast layer. The new layer, derived from differentiating cytotrophoblast cells, was largely formed by 48 h and was maintained for at least 120 h in culture. This study demonstrates a model which provides an opportunity to study the differentiation of cytotrophoblast cells whilst they retain their anatomical relationships within the villous structure.   相似文献   
33.
Primary congenital glaucoma (gene symbol: GLC3) is an ocular disorder that occurs for 0.01-0.04% of blind people. In the majority of familial cases reported so far, this condition is inherited as an autosomal recessive trait. We have recently used a group of 17 GLC3 families with a minimum of two affected offspring and consanguinity in most of the parental generation and mapped the first GLC3 locus (GLC3A) to the 2p21 region. Six families did not show any linkage to the GLC3A locus and thus provided evidence for genetic heterogeneity of this disorder. A total of eight families unlinked to the 2p21 region were used to search for the chromosomal location of the second GLC3 locus. Herein, we describe mapping of a new locus (designated GLC3B) for primary congenital glaucoma to the short arm of chromosome 1 (1p36.2-36.1) that is situated centromeric to the neuroblastoma and Charcot-Marie-Tooth type 2A (CMT2A) loci. A total of 17 DNA markers were genotyped from this region of chromosome 1. Four families showed no recombination with the two markers D1S2834 and D1S402 with a maximum lod score of 4.510 and 4.157 respectively. Pairwise and multipoint linkage analysis and inspection of the haplotypes revealed that the remaining four families are not linked to this part of chromosome 1, thus providing further evidence that at least one more locus for the autosomal recessive form of GLC3 must exist in the genome. Based on the recombination events, the overall linkage map of this region is: tel-D1S1192-D1S1635-D1S1193 - (D1S1597/-D1S489/D1S228)- [GLC3B/D1S2834/D1S402] - (D1S1176/D1S507/D1S407) - D1S2728-(MFAP2/D1S170) - D1S1368 - D1S436- D1S1592-cen.   相似文献   
34.
Stoppa‐Vaucher S, Ayabe T, Paquette J, Patey N, Francoeur D, Vuissoz J‐M, Deladoëy J, Samuels ME, Ogata T, Deal CL. 46, XY gonadal dysgenesis: new SRY point mutation in two siblings with paternal germ line mosaicism. Familial recurrence risks are poorly understood in cases of de novo mutations. In the event of parental germ line mosaicism, recurrence risks can be higher than generally appreciated, with implications for genetic counseling and clinical practice. In the course of treating a female with pubertal delay and hypergonadotropic hypogonadism, we identified a new missense mutation in the SRY gene, leading to somatic feminization of this karyotypically normal XY individual. We tested a younger sister despite a normal onset of puberty, who also possessed an XY karyotype and the same SRY mutation. Imaging studies in the sister revealed an ovarian tumor, which was removed. DNA from the father's blood possessed the wild type SRY sequence, and paternity testing was consistent with the given family structure. A brother was 46, XY with a wild type SRY sequence strongly suggesting paternal Y‐chromosome germline mosaicism for the mutation. In disorders of sexual development (DSDs), early diagnosis is critical for optimal psychological development of the affected patients. In this case, preventive karyotypic screening allowed early diagnosis of a gonadal tumor in the sibling prior to the age of normal puberty. Our results suggest that cytological or molecular diagnosis should be applied for siblings of an affected DSD individual.  相似文献   
35.
36.
37.
38.
Osteochondrodysplasias are a heterogeneous group of genetic skeletal dysplasias. Patients with these diseases commonly develop an early degenerative arthritis or osteoarthritis. Occasional observations of inflammatory arthritis have been made in this population but such observations are based on clinical grounds alone without confirmatory imaging studies. Four patients followed up in a paediatric rheumatology clinic with three different skeletal dysplasias, who had both clinical and radiological evidence of an inflammatory arthritis and coexistent degenerative arthritis, are described.  相似文献   
39.
Antro-choanal polyp is generally recognized to represent approximately 4-6% of all nasal polyps; however, it is much more prevalent in the pediatric population. It warrants special consideration in children because its clinical manifestations may be mimicked by other less benign conditions, such as juvenile angiofibroma, meningoencephalocele, and nasopharyngeal malignancies. Fifty patients with surgically treated nasal polyps were reviewed at the Montreal Children's Hospital, between 1976 and 1986. Fourteen (28%) were antro-choanal polyps. Our results are compared with the literature, and special emphasis was given to radiographic manifestations and the differential diagnoses.  相似文献   
40.
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