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   182346篇
  免费   17286篇
  国内免费   11798篇
耳鼻咽喉   1632篇
儿科学   1905篇
妇产科学   2428篇
基础医学   21885篇
口腔科学   3260篇
临床医学   23895篇
内科学   26708篇
皮肤病学   2208篇
神经病学   9505篇
特种医学   6462篇
外国民族医学   97篇
外科学   18586篇
综合类   29589篇
现状与发展   39篇
一般理论   22篇
预防医学   12229篇
眼科学   4760篇
药学   19695篇
  191篇
中国医学   10975篇
肿瘤学   15359篇
  2024年   733篇
  2023年   2983篇
  2022年   7787篇
  2021年   9793篇
  2020年   7365篇
  2019年   6338篇
  2018年   6622篇
  2017年   6075篇
  2016年   5684篇
  2015年   8723篇
  2014年   10581篇
  2013年   9777篇
  2012年   14253篇
  2011年   15401篇
  2010年   9828篇
  2009年   7558篇
  2008年   10045篇
  2007年   9509篇
  2006年   9129篇
  2005年   8866篇
  2004年   5679篇
  2003年   5145篇
  2002年   4261篇
  2001年   3599篇
  2000年   3794篇
  1999年   3851篇
  1998年   2287篇
  1997年   2340篇
  1996年   1780篇
  1995年   1731篇
  1994年   1511篇
  1993年   906篇
  1992年   1279篇
  1991年   1115篇
  1990年   895篇
  1989年   842篇
  1988年   761篇
  1987年   623篇
  1986年   458篇
  1985年   396篇
  1984年   190篇
  1983年   162篇
  1982年   93篇
  1981年   123篇
  1980年   79篇
  1979年   108篇
  1978年   52篇
  1977年   51篇
  1976年   42篇
  1974年   44篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
111.
112.
MICs of temocillin, carbenicillin, ticarcillin, mezlocillin, piperacillin and ampicillin were determined for mutant series of Enterobacter cloacae, Citrobacter freundii, Proteus vulgaris, Morganella morganii and Serratia marcescens with inducible, stably derepressed or basal expression of chromosomal Class I beta-lactamases. Ampicillin was inactive (MIC greater than 256 mg/l) both against beta-lactamase-inducible organisms (except C. freundii) and their stably derepressed mutants, whereas basal mutants were sensitive (MIC 2-8 mg/l). Carbenicillin, ticarcillin, mezlocillin, piperacillin (and ampicillin for C. freundii) were active against both inducible and basal organisms (MIC less than 16 mg/l), but inactive against the derepressed mutants (MICs usually greater than 64 mg/l). Temocillin inhibited all the organisms, including the stably derepressed mutants, at 16 mg/l. Derepressed S. marcescens, M. morganii and Pr. vulgaris were as susceptible as the inducible strains and basal mutants. MICs of temocillin for derepressed mutants of E. cloacae and C. freundii were 4-16 fold above those for their inducible parent strains, but remained within the clinical range.  相似文献   
113.
114.
a 54-year-old male was presented with huge, black, ulcerative and painless tumor of the sole of left foot. Malignant melanoma was proved by biopsy, but patient refused any treatment. He visited our hospital again when bloody vomitus was noted two months later. Chest P-A revealed multiple lung metastases, and marked liver metastasis was also found by abdominal echo. Upper gastrointestinal (UGI) panendoscopy revealed multiple melanotic nodules with ulcerations at the tip, scattering diffusely on the fundus and upper body of the stomach. Metastatic malignant melanoma was proved by endoscopic biopsy. Metastatic tumor of the stomach was rare, and the endoscopic finding of the malignant melanoma with gastric metastasis was more rarer in the literature in Taiwan. So we would like to present the very rare finding of the endoscopy.  相似文献   
115.
米非司酮作用于兔输卵管收缩活动与Ca^2+关系的研究   总被引:1,自引:0,他引:1  
通过“结合化学分离与原子吸收分光光度法”对Ca^2 含量测定和离体输卵管肌条收缩记录方法,研究米非司酮(Ru486)对增加假孕(4d)兔输卵管平滑肌收缩频率,而不改变其收缩张力和振幅时与Ca^2 之间的关系,结果提示:(1)Ru486对输卵管分泌液和组织内Ca^2 的含量分布无明显影响;(2)Ru486具有降低细胞外液高Ca^2 浓度促Ca^2 内流,而使收缩增强的效应,且能协同Ca^2 通道阻断剂(Verapamil)抑制细胞外Ca^2 内流,而致收缩减弱的效应。  相似文献   
116.
The beneficial effects of transcutaneous electrical stimulation of the P6 antiemetic point (Neiguan) as an adjuvant to standard antiemetics was studied in over 100 patients in whom chemotherapy-induced sickness was not adequately controlled by antiemetics alone. Although the results were not quite as good as with invasive acupuncture, more than 75% patients achieved considerable benefit from what was a non-toxic procedure. The use of large diffuse low impedence electrodes simplifies the technique. The 2 hourly application of Sea Bands prolongs the antiemetic action. Best results were obtained from the 2 hourly self-administration of 5 min of transcutaneous electrical stimulation of P6 using a simple battery-operated TENS machine (15 Hz) to activate a large, easy-to-place surface electrode and increasing current until Qi is elicited.  相似文献   
117.
118.
S W Yang  N A Langrana  C K Lee 《Spine》1986,11(9):937-941
The current study investigates the stabilizing effects of three different types of spinal fusion to the juxta-free motion segments and to the fused segment of the lumbosacral spine under combined compression-torsion loads. Sixteen fresh human cadaver lumbosacral spines were tested under a simulated physiologic loading condition. The relative movements of the motion segments, as well as the angular rotations and the center of rotation were then computed and analyzed. The average torsional stiffness of the unfused three-motion segment was found to be 2.35 nm/degree. After fusion, the torsional stiffness did not increase significantly. Under the compression-torsional load, the anterior and bilateral-lateral fusions provided adequate stabilizing effect on the fused segment. The posterior fusion provided the least amount of stabilizing effect. These findings are similar to the results of the compression-bending experiment. Whereas the compression-bending loads produced significantly increased stress at the juxta-free segments, the compression-torsional loads did not produce any significant amount of increase in torsional stress at the juxta-free segments.  相似文献   
119.
电针加穴位注射治疗偏头痛28例   总被引:1,自引:0,他引:1  
笔者在临床中以电针、穴位注射治疗偏头痛,取得较好的疗效,现介绍如下。一般资料本组病例共28例,其中男性6例,女性22例;年龄26~58岁,平均42岁;病程3~18年,平均10.5年。治疗方法电针加TDP照射:取穴:太阳、阳白透鱼腰、率谷透角孙、风池、合谷、列缺。辨证加减:有痰加丰隆、印堂;  相似文献   
120.
目的了解截瘫患者医院感染的病原菌对药物敏感情况. 方法回顾分析我院自1996年9月~2003年11月,316例截瘫患者的有关临床资料. 结果 98例患者发生医院感染,医院感染率为31.01%,感染部位主要以呼吸道、皮肤软组织、手术切口、泌尿道感染为多;医院感染的病原菌主要是条件致病菌,以G-菌为主.结论医护人员必须严格无菌操作,根据细菌药敏结果合理选用抗菌药物,加强营养,提高患者机体抵抗力.  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