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   876篇
  免费   36篇
  国内免费   2篇
耳鼻咽喉   2篇
儿科学   24篇
妇产科学   3篇
基础医学   53篇
口腔科学   140篇
临床医学   47篇
内科学   110篇
皮肤病学   49篇
神经病学   63篇
特种医学   52篇
外科学   200篇
综合类   24篇
预防医学   30篇
眼科学   11篇
药学   68篇
中国医学   3篇
肿瘤学   35篇
  2023年   5篇
  2021年   14篇
  2020年   10篇
  2019年   16篇
  2018年   30篇
  2017年   12篇
  2016年   23篇
  2015年   16篇
  2014年   28篇
  2013年   45篇
  2012年   65篇
  2011年   51篇
  2010年   20篇
  2009年   17篇
  2008年   30篇
  2007年   27篇
  2006年   32篇
  2005年   35篇
  2004年   30篇
  2003年   26篇
  2002年   38篇
  2001年   29篇
  2000年   35篇
  1999年   23篇
  1998年   9篇
  1997年   8篇
  1995年   11篇
  1994年   3篇
  1993年   4篇
  1992年   15篇
  1991年   19篇
  1990年   7篇
  1989年   11篇
  1988年   17篇
  1987年   15篇
  1986年   10篇
  1985年   8篇
  1984年   13篇
  1983年   9篇
  1979年   8篇
  1978年   6篇
  1977年   13篇
  1976年   3篇
  1975年   10篇
  1974年   9篇
  1973年   4篇
  1972年   15篇
  1971年   5篇
  1970年   3篇
  1969年   8篇
排序方式: 共有914条查询结果,搜索用时 15 毫秒
1.
2.
3.
G S Bedi  N Back 《Hybridoma》1987,6(5):521-526
Five hybridoma cell lines were established that secrete monoclonal antibodies (MAbs) directed against rat plasma low molecular weight plasma kininogen. Two of the secreted antibodies were of the IgG1k isotype. The remaining three were of the IgG1 lambda, IgG2ak and IgMk isotypes, respectively. The dissociation constants (Kd) of these MAbs ranged from 0.58 X 10(-9) M to 5.4 X 10(-9) M. At least two distinct epitopes on the rat plasma kininogen were recognized by these MAbs. Further characterization of the MAbs showed that four MAbs cross-reacted strongly with kininogen from the Murphy-Sturm lymphosarcoma (MSLS) tumor while one of the MAbs cross-reacted weakly with MSLS tumor kininogen.  相似文献   
4.
5.
A case of placenta membranacea, previa and accreta was managed conservatively and resulted in delivery of a mature fetus. The diagnosis of placenta membranacea and previa was obtained with ultrasound. The placenta previa and accreta necessitated a cesarean delivery and hysterectomy.  相似文献   
6.
The aim of this study was to determine the self-reported preventive oral health related behaviours of dentally anxious schoolchildren. 1103 children participated in the study, mean age 14 years (SD 0.35 years), and the prevalence of high dental anxiety was 7.1 per cent (95 per cent confidence interval = 5.6 per cent, 8.6 per cent). Children with high self reported dental anxiety were more likely to defer, cancel and or not attend dental appointments. In addition, for this group the last dental visit was more likely to be as a result of pain and less likely to have been for a dental examination only. Overall dentally anxious children did not help themselves by keeping their teeth clean. Fluorides were infrequently used by all the children, and only 12 per cent of all who participated in the study used fluoride supplements regularly. In this context it is not surprising that no differences in present or past use of fluoride supplements could be determined between high and low/moderate dental anxiety groups. The high dental anxiety group spend significantly more (median = 50p) on sweets per day and drank more cans of fizzy drinks (median = 2) compared with the low/moderate anxiety groups. These effects were significant after taking into account social class and gender differences. It was clear from the study that even when social class and gender are taken into account the children with high dental anxiety were not helped by their relatively poor attitudes towards preventing disease in their own mouths.  相似文献   
7.
Use of seclusion and restraint on three inpatient adolescent psychiatric units was examined during two five-month periods before and after implementation of a "therapeutic management" protocol. Under the protocol, staff classified disruptive behaviors into four stages and provided verbal and behavioral interventions to control behavior at each stage. Patients who required seclusion and restraint had significant latitude to determine the timing of their release from the interventions and met with staff one hour and 24 hours after their release to explore alternatives to aggression. The number of episodes of seclusion and restraint fell by 64 percent after the protocol was adopted, and the number of patients who required those interventions dropped by 39 percent. The mean duration of episodes of seclusion and restraint was reduced by 59 percent. Therapeutic management provides a corrective experience by addressing the developmental needs, deficient cognitive skills, and poor internalized controls of disruptive adolescents.  相似文献   
8.
Recent research has shown that a lengthy period of undernutrition during early postnatal life can cause alterations in the morphological structure of the dentate gyrus. As this region is involved in the control of spatial memory, we decided to investigate whether undernourished rats also showed any deficits in this aspect of behaviour. Rats were undernourished from about birth until either 30 or 60 days of age and then nutritionally rehabilitated for a lengthy period before testing. There were significant differences in the body weight of control and undernourished rats in each experiment. The testing procedure involved rats being placed in a large pool of opaque water. They were required to swim to find a hidden platform located just below the water surface onto which they could escape. Each rat had to perform this test 20 times over a period of 3 days. The time taken and the total distance swum by each rat during each trial was measured. In Experiment 1, rats were familiarised with the water before testing took place, whereas in Experiment 2 they were not. There were no significant differences in the latency to find the platform or the distance swum between well-fed control and previously undernourished rats in either experiment. In conclusion, in our experiments we could not demonstrate that undernutrition during early life caused any deficits in spatial memory performance.  相似文献   
9.
10.
Sixty-three (5%) of 1239 women studied by sonography during the second trimester of their pregnancies had a diagnosis of placenta previa. Follow-up was available for 51 of the 63 patients; in three of these, the original diagnosis was complete placenta previa, and in the other 48, the first diagnosis was partial or marginal placenta previa. At term, placenta previa was seen in only four patients for an overall frequency of 0.3% (4/1227). In all three of the patients with complete placenta previa, the condition persisted from the second trimester to term; previa persisted in only one of 48 patients with marginal/partial previa. Because of the infrequent persistence of marginal or partial placenta previa to term, we recommend using the term "potential placenta previa" in the second trimester, with follow-up sonography indicated only for vaginal bleeding.  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