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   658篇
  免费   44篇
  国内免费   4篇
耳鼻咽喉   3篇
儿科学   27篇
妇产科学   8篇
基础医学   66篇
口腔科学   17篇
临床医学   49篇
内科学   136篇
皮肤病学   16篇
神经病学   15篇
特种医学   176篇
外科学   49篇
综合类   39篇
一般理论   1篇
预防医学   32篇
眼科学   6篇
药学   52篇
中国医学   1篇
肿瘤学   13篇
  2022年   3篇
  2021年   4篇
  2020年   3篇
  2019年   5篇
  2018年   9篇
  2017年   5篇
  2016年   8篇
  2015年   12篇
  2014年   5篇
  2013年   17篇
  2012年   15篇
  2011年   21篇
  2010年   16篇
  2009年   19篇
  2008年   23篇
  2007年   19篇
  2006年   14篇
  2005年   21篇
  2004年   18篇
  2003年   18篇
  2002年   13篇
  2001年   20篇
  2000年   14篇
  1999年   8篇
  1998年   23篇
  1997年   40篇
  1996年   28篇
  1995年   23篇
  1994年   16篇
  1993年   17篇
  1992年   16篇
  1991年   13篇
  1990年   15篇
  1989年   15篇
  1988年   29篇
  1987年   24篇
  1986年   24篇
  1985年   18篇
  1984年   14篇
  1983年   6篇
  1982年   11篇
  1981年   15篇
  1980年   14篇
  1979年   3篇
  1978年   7篇
  1977年   7篇
  1976年   8篇
  1975年   5篇
  1967年   1篇
  1841年   1篇
排序方式: 共有706条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Cholecystokinin-decreased food intake in rhesus monkeys   总被引:1,自引:0,他引:1  
  相似文献   
6.
This study analyses the influence of female and male patient age and human menopausal gonadotrophin (HMG) requirements on clinical pregnancy rates and live birth rates with ovulation stimulation using HMG in combination with intrauterine insemination (IUI). In this study, 363 consecutive HMG/IUI treatment cycles in 184 patients carried out at a university fertility centre were analysed in a retrospective fashion. The main outcomes measured were clinical pregnancy rates and live birth rates. Increased female partner age (> or = 35) and male partner age (> or = 40) were found to negatively influence pregnancy rates with HMG/ IUI therapy. In addition, this study demonstrated a critical threshold of HMG requirements beyond which pregnancy did not occur. No pregnancies occurred in treatment cycles requiring > 25 ampoules (1875 IU) of menotrophins to achieve follicular maturity, irrespective of patient age. In conclusion, female partner age, male partner age, and HMG requirements all significantly influence pregnancy rates with HMG/IUI therapy.   相似文献   
7.
INTRODUCTION: Core biopsy of the breast has become the method of choice for tissue diagnosis of screen detected microcalcifications and some mass lesions in many breast assessment centres. Biopsy results are not available until the following day. Imprint cytology of fresh breast core samples allows same-day reporting and patient counselling.
AIM: To determine the accuracy of core imprint cytology when compared with core biopsy diagnosis when used in a breast assessment centre setting.
METHODS: Core imprints (CI) were prepared and reported on all fresh core biopsies (CB) performed at the Sir Charles Gairdner Hospital Breast Centre from May to December 2000. Fresh core samples were placed on a glass microscope slide. Core radiographs were taken for microcalcification lesions (MC). A laboratory technician gently and quickly rolled the cores on the slide with fine forceps. The cores were fixed in formalin, processed and reported next day. The imprint slide was air dried and stained with DiffQuik. CI were reported using four categories: Insufficient, Benign, Indeterminate and Malignant. Counselling and planning for management were possible on the same day in women with malignant diagnoses. Clinicians were advised not to discuss negative or indeterminate CI results with women and to defer to the final CB report.
RESULTS: Cores were performed on 381 lesions. There were 83 carcinomas (38 in MC and 45 in masses) and 56 were called malignant on CI (absolute sensitivity 67.5%; 78.9% for MC and 57.8% for masses). 3 malignancies on CB were negative on CI giving a false negative rate of 3.6%. There were no false positive diagnoses. The predictive value of a benign diagnosis was 95.3%. There were no adverse effects in the histology of CB.
CONCLUSION: CI was an accurate method of providing an immediate diagnosis of malignancy in two thirds of malignancies confirmed on CB.  相似文献   
8.
The theoretical small signal impedance of the frog node,Rana pipiens   总被引:1,自引:0,他引:1  
Summary The small signal impedance of the frog node is calculated for frequencies from 1 Hz to 10,000 Hz and transmembrane potentials from –80 mV to –30 mV by linearizing the voltage clamp equations of Dodge [7] and Hille [8]. The modulus of the impedance is presented for the total system, and separately for the potassium and sodium systems as a function of frequency and voltage. There is a broad resonance in the total impedance with a voltage-dependent peak frequency. At 22°C, in the range –75 mV to –45 mV, the peak frequencies occur between 50 and 500 Hz. Removing the potassium system leaves a relatively shapr resonance centered around 200 Hz at –45 mV.  相似文献   
9.
10.
Adrenergic mechanisms in cerebral circulation of the goat   总被引:1,自引:0,他引:1  
  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