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   18318篇
  免费   1215篇
  国内免费   100篇
耳鼻咽喉   171篇
儿科学   483篇
妇产科学   382篇
基础医学   2106篇
口腔科学   320篇
临床医学   1509篇
内科学   3830篇
皮肤病学   225篇
神经病学   1020篇
特种医学   516篇
外科学   3274篇
综合类   636篇
一般理论   17篇
预防医学   1407篇
眼科学   500篇
药学   1835篇
中国医学   218篇
肿瘤学   1184篇
  2023年   143篇
  2022年   381篇
  2021年   649篇
  2020年   420篇
  2019年   527篇
  2018年   637篇
  2017年   442篇
  2016年   359篇
  2015年   499篇
  2014年   689篇
  2013年   860篇
  2012年   1282篇
  2011年   1262篇
  2010年   729篇
  2009年   561篇
  2008年   988篇
  2007年   994篇
  2006年   911篇
  2005年   839篇
  2004年   767篇
  2003年   689篇
  2002年   580篇
  2001年   544篇
  2000年   487篇
  1999年   389篇
  1998年   147篇
  1997年   115篇
  1996年   110篇
  1995年   117篇
  1994年   60篇
  1993年   75篇
  1992年   202篇
  1991年   186篇
  1990年   163篇
  1989年   172篇
  1988年   137篇
  1987年   152篇
  1986年   124篇
  1985年   134篇
  1984年   110篇
  1983年   86篇
  1982年   59篇
  1981年   60篇
  1979年   97篇
  1978年   64篇
  1977年   66篇
  1975年   60篇
  1974年   51篇
  1973年   54篇
  1972年   50篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
OBJECTIVES: To determine the accuracy of self-reported comorbidities compared with medical record review and the clinical and sociodemographic characteristics associated with accuracy of self-reported comorbidities. STUDY DESIGN: We conducted a prospective study of 458 newly diagnosed head and neck cancer patients using self-administered questionnaire and medical chart review data. Overall and itemwise consistency between self-report and chart review was evaluated. Social, clinical, and demographic characteristics of consistent versus inconsistent responders were analyzed. RESULTS: Seventy-four percent of patients had at least one comorbidity. There was good overall consistency between self-report and chart review (kappa = 0.50). Compared with consistent responders, inconsistent responders were found to be older (P < 0.05), have lower sleep (P < 0.05) and physical activity scores (P < 0.05), be more depressed (P < 0.05), and have more severe comorbidities (P < 0.05). CONCLUSIONS AND SIGNIFICANCE: Self-report may be considered as an alternative to chart review for comorbidity assessment in head and neck cancer patients. Younger patients, those with good general health, fewer depressive symptoms, and mild comorbidities, are more likely to give responses consistent with chart review.  相似文献   
73.
Disulfiram, an alcohol antagonistic drug has been on the market since 1949 with 80% bioavailability and an established safety profile. Recently it has been reported as a P-glycoprotein efflux pump modulator. Herein we report its antifungal potential. The MIC50 and MIC90 of disulfiram for yeast isolates is 4 and 8 microg/ml, respectively, and the MIC range is 1-16 micro g/ml for both fluconazole sensitive and resistant strains. Interestingly, disulfiram also showed fungicidal activity on Aspergillus spp. with MIC50 and MIC90 of 2 and 8 microg/ml, respectively.  相似文献   
74.
Tension development in response to direct and indirect electrical stimulation was studied in an isolated phrenic nerve hemidiaphragm preparation of the mouse. β-Endorphin (β-EP) caused an increase in the preparation of the mouse. β-Endorphin (β-EP) caused an increase in the response to low frequency stimulation of the nerve. Upon direct stimulation of the muscle the peptide had no effect. The actions of β-EP were abolished in the presence of the opioid antagonist naloxone and mimicked by β opioid agonists. Upon high frequency stimulation of the nerve, β-EP caused an increase in the initial, maximum, and mean tension. It also prevented the fall in the final tension seen in the control preparations with repeated periods of stimulation. The findings are consistent with β-EP having a role to improve neuromuscular function and deley fatigue, and indicate the possible therapeutic potential of opioid substances in conditions where muscle weakness is present. © John Wiley & Sons, Inc.  相似文献   
75.
路路通内酯的化学结构   总被引:4,自引:1,他引:3  
孙玉茹  孙友富 《药学学报》1996,31(6):437-440
用红外,质谱,1H,13CNMR和1H-13CCOLOC等光谱解析,确定了新化合物路路通内酯的结构为3-羰基-11α,12α-环氧-13β-氧-齐墩果-28β-酸-13,28-γ-内酯,命名为路路通内酯。  相似文献   
76.
77.
After sustaining a free rupture of the intrapericardial ascending aorta secondary to blunt chest trauma, a 27-year-old man underwent successful aortic repair. To our knowledge, this is the first time a patient has ever survived this condition. Pericardial tamponade-together with rapid transport to the hospital and an aggressive surgical approach-was a key to the recovery of effective cardiac function and successful aortic repair. Although the patient succumbed to complications 74 days after surgery, this case illustrates the possibility of longterm survival after free rupture of the ascending aorta. The following report emphasizes the technical feasibility of controlling the perforated aortic root in such cases.  相似文献   
78.
79.
Neural representations created in the absence of external sensory stimuli are referred to as imagery, and such representations may be augmented by reenactment of sensorimotor processes. We measured nasal airflow in human subjects while they imagined sights, sounds and smells, and only during olfactory imagery did subjects spontaneously enact the motor component of olfaction--that is, they sniffed. Moreover, as in perception, imagery of pleasant odors involved larger sniffs than imagery of unpleasant odors, suggesting that the act of sniffing has a functional role in creating of olfactory percepts.  相似文献   
80.
A new antitumor compound, cis-platinum (II) diamminodichloride, suppressed antibody plaque-forming cells in C(3)H mice when given in a single dose of 10 mg per kg of body weight within 2 days before or after sensitization.  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