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   164530篇
  免费   15885篇
  国内免费   11142篇
耳鼻咽喉   1732篇
儿科学   2242篇
妇产科学   1376篇
基础医学   15078篇
口腔科学   2870篇
临床医学   20158篇
内科学   20400篇
皮肤病学   1929篇
神经病学   6535篇
特种医学   6193篇
外国民族医学   68篇
外科学   17001篇
综合类   35622篇
现状与发展   49篇
一般理论   10篇
预防医学   14044篇
眼科学   3651篇
药学   17515篇
  191篇
中国医学   12606篇
肿瘤学   12287篇
  2024年   631篇
  2023年   2314篇
  2022年   5974篇
  2021年   7739篇
  2020年   6231篇
  2019年   4666篇
  2018年   5114篇
  2017年   5203篇
  2016年   4909篇
  2015年   7800篇
  2014年   9505篇
  2013年   9910篇
  2012年   14304篇
  2011年   15348篇
  2010年   11606篇
  2009年   9693篇
  2008年   10867篇
  2007年   10425篇
  2006年   9753篇
  2005年   8269篇
  2004年   5855篇
  2003年   5504篇
  2002年   4545篇
  2001年   3439篇
  2000年   2644篇
  1999年   2025篇
  1998年   1171篇
  1997年   1104篇
  1996年   878篇
  1995年   793篇
  1994年   604篇
  1993年   378篇
  1992年   404篇
  1991年   327篇
  1990年   296篇
  1989年   232篇
  1988年   198篇
  1987年   193篇
  1986年   144篇
  1985年   110篇
  1984年   57篇
  1983年   44篇
  1982年   33篇
  1981年   38篇
  1980年   20篇
  1979年   42篇
  1977年   19篇
  1976年   19篇
  1974年   22篇
  1973年   28篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
911.
Objective. To undertake the pilot experiments of prevention of disability (POD) in 14 different geographical areas to serve as examples for future development of rehabilitation work in China and in Asia. Mahods. According to the principles mid national criterion, 27 000 people affected by leprosy were selected and assessed using disability record forms at beginning and followed up regularly for observing changes of different indica-tors. Results. A total of 197 neuritis cases were detected and treated with prednisolone out of 1 407 new or active cas-es. Serf-care training of eyes, hands and feet were conducted for 10 500 disabled people affected by leprosy. Compre-hensive therapy was given to 1 804 cases having comphcated ulcers of which 1 055 cases have got their ulcers healed. Out of 706 prostheses, 613 were given to patients with satisfactory results. Surgical treatment was given to 269 cases and 251 have shown good progress. Conclusion. Most of patients have got benefit from the project in function or appearance which is very helpful for their going back to the society and agreed by foreign experts during the final evaluation. The experiences from the pro-ject can be implemented in the whole country.  相似文献   
912.
佛山市致乏库蚊对3种杀虫剂的抗性监测   总被引:1,自引:0,他引:1  
目的:了解佛山市优势蚊种致乏库蚊对溴氰菊酯、氯菊酯、马拉硫磷3种常用杀虫剂的抗性水平,为科学、合理使用药物提供依据。方法:浸渍法。结果:致乏库蚊对溴氰菊酯、氯菊酯、马拉硫磷的LC_(50)分别为0.000537mg/L、0.03439mg/L和0.156mg/L,与其敏感品系对这三种杀虫剂的LC_(50)比较,前者是后者的2.8倍、6.1倍和2.1倍。结论:这3种药物对致乏库蚊均未引起明显的抗药性。但应注意合理使用药物,延缓抗性的进一步发展。  相似文献   
913.
PF方案化放治疗晚期鼻咽癌的远期疗效   总被引:29,自引:0,他引:29  
Gu Z  Wei Q  Huang K 《中华肿瘤杂志》1997,19(5):392-394
目的探索用PDD/5-Fu方案化放治疗晚期鼻咽癌的疗效。方法1989年12月~1990年12月间,选择76例Ⅲ、Ⅳ期鼻咽癌患者,先作3周期PDD(20mg(m2)-1d-1,iv,第1~5天)和5-Fu[700mg(m2)-1d-1,连续静脉滴注,第1~5天]诱导化疗,随后尽快作放疗,此为综合治疗组。以1989年作单纯放疗的86例晚期鼻咽癌患者作对照组。两组放疗方法、时间/剂量分割均相同。结果化疗有效率为89.3%,完全缓解率为18.4%。综合治疗组(综合组)总的5年生存率为48.7%,对照组为33.7%(P>0.05)。综合组T2N3和T2~4N3患者的5年生存率为44.1%和39.5%,均明显高于对照组的21.6%及20.4%(P<0.05)。结论PF方案化放治疗提高了T2~4N3患者的5年生存率。  相似文献   
914.
压力对体外培养牛眼小梁细胞的影响   总被引:3,自引:1,他引:2  
Jiang F  Wei H  Lu Y 《中华眼科杂志》1997,33(6):410-412,I025
目的 观察压力对小梁细胞的影响。方法 对体外培养牛眼小梁细胞施以不同程度的压力,用倒置相差显微镜、光镜、电镜观察细胞形态结构及吞噬功能的变化。结果 细胞承受2.00kpa(1kpa=7.5mmHg)、2.67kpa压力48小时,各项指标与对照组比较,差异无显著性。4.00kpa24小时,细胞形态结构有轻度的损伤,吞噬功能有轻度下降。当压力进一步增加,时间更加延长后,细胞的损伤也更重。结论小梁细胞只  相似文献   
915.
陵水暗罗活性成分研究   总被引:8,自引:0,他引:8  
姚建忠  梁华清  廖时萱 《药学学报》1994,29(11):845-850
从陵水暗罗(polyalthia nemoralis A.etDC)根的乙醇提取物中分离得到五个化合物。经光谱(UV,IR,1H-NMR,13C-NMR,DEPT和MS)解析和化学反应,分别鉴定为暗罗素(zincpolyanemine,PN1),2-巯基吡啶-N-氧化物铜盐(PN2),β-谷甾醇(PN3),β-谷甾醇-β-D-吡喃葡萄糖甙(PN4)和2-巯基吡啶-N-氧化物-2-S-β-D-吡喃葡萄糖甙(PN5),其中PN5为新化合物,PN2为新天然产物。PN1和PN2有较强抗疟、防霉杀菌作用。PN5的抗疟、防霉试验尚在进行中。  相似文献   
916.
SEARCHFORHERPESSIMPLEXVIRUSTYPE2(HSV-2)ANDHUMANPAPILLOMAVIRUS(HPV)INTHENORMALANDABNORMALCERVICALSAMPLESZhangWei;张伟;JinShunqia...  相似文献   
917.
The relationship of scapulothoracic motion to glenohumeral motion, commonly referred to as the scapulohumeral rhythm, has been the subject of numerous investigations. The purpose of this study was to assess the effects of localized muscular fatigue on three-dimensional scapulothoracic motion and the resulting scapulohumeral rhythm during elevation of the humerus in the plane of the scapula. A six-degree-of-freedom digitizing system (Metrecom(TM)) was used to define scapular and trunk reference frames, and three-dimensional Eulerian angles were determined for scapular motion for 0-135 degrees of humeral elevation before and after fatigue of the upper and lower trapezius muscles. Local muscle fatigue was determined using spectral analysis of electromyographic signals for the upper and lower trapezius muscles. The results demonstrated an average of 22% decrease in the median frequencies of the muscles sampled following resistive exercise, suggesting a state of local muscle fatigue. Concomitant with the fatigue was a selective decrease in scapulothoracic motion about two of the three scapular axes. RELEVANCE: Occupational and recreational conditions often require repetitive overhead elevations of the arms, resulting in muscular fatigue and various pathologies. During repetitive arm elevations the scapulohumeral rhythm or synchronization between the humerus and the scapula is balanced to allow the most efficient elevation of the arm. A better understanding of this much-discussed scapulohumeral rhythm and the changes induced by muscular fatigue may provide insight into the pathomechanics associated with shoulder dysfunction.  相似文献   
918.
Purpose. Highly variable drugs pose a problem in bioequivalence assessment because they often fail to meet current regulatory acceptance criteria for average bioequivalence (80–125%). This paper examines alternative approaches to establishing bioequivalence. Methods. Suggested solutions have included alternate study designs, e.g., replicate and multiple dose studies, reducing the level of the confidence interval, and widening the acceptance limits. We focus on the latter approach. Results. A rationale is presented for defining wider acceptance limits for highly variable drugs. Two previously described methods are evaluated, and a new method having more desirable properties is proposed. Conclusions. We challenge the one size fits all current definition of bioequivalence acceptance limits for highly variable drugs, proposing alternative limits or goal posts which vary in accordance with the intrasubject variability of the reference product.  相似文献   
919.
Gao  Qi  Wei  Jian-Mei  Chen  Shu-Hui 《Pharmaceutical research》1995,12(3):337-341
Crystals of the C2-acetate analog of paclitaxel, grown from a mixture of isopropyl alcohol and methanol, belong to the space group P2l with a = 9.058(3), b = 18.306(5), c = 15.043(1) , = 97.09(1)°, Z = 2, V = 2475.1(9)3, D calc = 1.269 gcm–3 and µ = 0.75 cm–1. The structure was determined by direct methods and refined to R(F) = 0.054 and wR(F) = 0.057 for 605 variables and 3496 observed reflections. The paclitaxel side chain possesses a conformation similar to that observed in the crystal structure of docetaxel (Taxotere®). A three dimensional network of hydrogen bonds is formed through solvent molecules and stabilizes the crystal lattice.  相似文献   
920.
杨伟  轩莉 《中国卫生经济》1999,18(12):57-59
1998年,上海市普陀区医疗保险办公室改革公费医疗支付方式,对门诊项目实行按人头付费。本文就改革实施一年来公费医疗费用发生情况作一分析,对按人头付费方式实施效果进行评估,得出以下结论:该支付方式较为有效地降低了医疗费用的增长幅度,减少了浪费;对促进医院加强内部管理,转变经营策略,重视医疗成本控制,提高卫生资源的利用效率起到了积极的作用。同时提出,要注意纠正个别医疗机构控制费用方法简单化的偏差,要考虑人群年龄结构因素对医疗费用的影响,适当调整付费标准,以避免医疗机构在承担费用支出方面出现畸轻畸重的问题。  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