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   948157篇
  免费   67188篇
  国内免费   1405篇
耳鼻咽喉   13186篇
儿科学   24803篇
妇产科学   23567篇
基础医学   135258篇
口腔科学   28535篇
临床医学   82008篇
内科学   186442篇
皮肤病学   19740篇
神经病学   74226篇
特种医学   37710篇
外国民族医学   79篇
外科学   154275篇
综合类   18162篇
现状与发展   1篇
一般理论   238篇
预防医学   62560篇
眼科学   21548篇
药学   73438篇
  3篇
中国医学   2222篇
肿瘤学   58749篇
  2018年   9381篇
  2017年   7406篇
  2016年   8230篇
  2015年   9320篇
  2014年   12627篇
  2013年   18269篇
  2012年   25303篇
  2011年   26321篇
  2010年   15566篇
  2009年   14927篇
  2008年   25683篇
  2007年   26766篇
  2006年   27519篇
  2005年   26450篇
  2004年   25422篇
  2003年   24416篇
  2002年   23897篇
  2001年   54860篇
  2000年   56656篇
  1999年   47105篇
  1998年   10904篇
  1997年   9593篇
  1996年   9721篇
  1995年   9008篇
  1994年   8365篇
  1993年   7652篇
  1992年   35534篇
  1991年   33962篇
  1990年   32772篇
  1989年   31892篇
  1988年   29018篇
  1987年   28279篇
  1986年   26311篇
  1985年   25172篇
  1984年   17856篇
  1983年   15163篇
  1982年   7823篇
  1981年   6795篇
  1979年   15803篇
  1978年   10622篇
  1977年   9084篇
  1976年   7890篇
  1975年   8643篇
  1974年   10474篇
  1973年   9871篇
  1972年   9364篇
  1971年   8858篇
  1970年   8432篇
  1969年   7931篇
  1968年   7209篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Premalignant lesions of the penis include cutaneous horn, balanitis xerotica obliterans, and leukoplakia. The true incidence of progression of each of these to squamous-cell carcinoma is unknown. Bowenoid papulosis, erythroplasia of Queyrat, and Bowen's disease are histologically identical to in situ carcinoma. Although the first is consistently benign, the latter two regularly evolve into invasive cancer. Malignant scrotal lesions include squamous-cell carcinoma, liposarcoma, leiomyosarcoma, basal-cell carcinoma, extramammary Paget's disease, erythroplasia of Queyrat, malignant melanoma, and metastases. Hemangioma can be confused with carcinoma.  相似文献   
62.
63.
Cerebral function in normoxia and its reactions to standard periods of hypoxia of increasing severity were studied in 30 newborn guinea pigs less than 3 days old. Intrauterine growth retardation was induced either by uterine artery ligation at midgestation or by feeding the female in late gestation with khat leaves, an amphetamine-like stimulant chewed by men and women in several countries in eastern Africa and Arabia. After spontaneous delivery, the neonates were anesthetized and ventilated. Cardiovascular, metabolic, and neurophysiologic (somatosensory evoked potentials) parameters were monitored. Under normoxia, the khat-exposed group showed prolonged latency of the primary response of the somatosensory evoked potentials and a reduced amount of secondary components. Under hypoxia, this group also has a greater reduction of amplitude of the somatosensory evoked potentials. It is concluded that khat exposure during fetal life has an impact on the cerebral function during the neonatal period (at least up to 3 days of age) which is not solely explained by the concomitantly produced growth retardation.  相似文献   
64.
This study examined electromyogram (EMG) and skin conductance level (SCL) as mediators of neuropsychological test performance of alcoholics. Alcoholics and controls with high EMG performed less well than low EMG subjects on 12 measures of neuropsychological performance. For SCL, the alcoholics and controls in the Low Group did not differ from those in the High Group on any measure. Analyses that used information intake (Low EMG and High SCL) and rejection (High EMG and Low SCL) information postures (IPs) demonstrated that the intake group outperformed the rejection group on 10 neuropsychological measures. Subjects with intake IPs reported more stimulation, concentration, and interest during the tasks than did subjects with rejection IPs. Results suggest that IPs can be used to identify alcoholics with neuropsychological deficits.  相似文献   
65.
Various forms of signal processing are used in modern ASP hearing aids. The present study investigated the relationship between sentence recognition ability and two types of signal processing used in commercially available hearing aids. Results indicated a significant improvement in sentence recognition ability employing an instrument with adaptive compression (variable release time) versus an instrument with an adaptive high-pass filter with short attack and release times. Data were obtained for a single-talker competing message at several message-to-competition ratios. The adaptive compression system may prove to be beneficial to hearing-impaired listeners in certain background noise environments.  相似文献   
66.
Facial reanimation after acoustic neuroma excision is currently accomplished using a variety of surgical techniques. A multi-institutional survey of patient perceptions of facial reanimation success was accomplished by mailing a questionnaire to 809 randomly selected members of the Acoustic Neuroma Association. Four hundred sixty patients who underwent 296 reanimation procedures responded. Facial to hypoglossal nerve anastomosis, tarsorrhaphy, and upper eyelid implants were most frequently performed. The patient's estimations of initial deficit, spontaneous recovery, and overall satisfaction with the reanimation procedures are discussed.  相似文献   
67.
68.
69.
70.
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