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   656955篇
  免费   89006篇
  国内免费   38026篇
耳鼻咽喉   6072篇
儿科学   11583篇
妇产科学   9157篇
基础医学   79493篇
口腔科学   14723篇
临床医学   90841篇
内科学   105099篇
皮肤病学   13406篇
神经病学   41277篇
特种医学   23142篇
外国民族医学   308篇
外科学   68929篇
综合类   101379篇
现状与发展   125篇
一般理论   97篇
预防医学   45371篇
眼科学   17696篇
药学   67104篇
  576篇
中国医学   35516篇
肿瘤学   52093篇
  2024年   1888篇
  2023年   8197篇
  2022年   21269篇
  2021年   28494篇
  2020年   25348篇
  2019年   27180篇
  2018年   27565篇
  2017年   27684篇
  2016年   27032篇
  2015年   35412篇
  2014年   41858篇
  2013年   40279篇
  2012年   46887篇
  2011年   51711篇
  2010年   39838篇
  2009年   30573篇
  2008年   34670篇
  2007年   33637篇
  2006年   32362篇
  2005年   31176篇
  2004年   21318篇
  2003年   20092篇
  2002年   17109篇
  2001年   15179篇
  2000年   14924篇
  1999年   14752篇
  1998年   8812篇
  1997年   8600篇
  1996年   6661篇
  1995年   6212篇
  1994年   5384篇
  1993年   3472篇
  1992年   4689篇
  1991年   4135篇
  1990年   3473篇
  1989年   3028篇
  1988年   2570篇
  1987年   2340篇
  1986年   1918篇
  1985年   1460篇
  1984年   893篇
  1983年   668篇
  1982年   384篇
  1981年   379篇
  1980年   309篇
  1979年   404篇
  1978年   224篇
  1977年   180篇
  1974年   177篇
  1973年   145篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
141.
The promoting effect of the Chinese medicinal herb, Wikstroemia chamaedaphne and Tung oil extracts (WC and HHPA) on carcinoma of uterine cervix induced by HSV-2 or MCA in mice was studied. The results showed that WC and HHPA extracts were not carcinogenic themselves. After carcinogen HSV-2 and MCA treatment, WC and HHPA were added separately. The inducing rates by HSV-2 increased from 7.4% to 21.1% and 26.3%, those by MCA increased from 56.5% to 82.8% and 84.4%. There was a significant difference between the combined groups and groups with HSV-2 or MCA only. The experimental results suggest that these two kinds of extracts play a promoting effect on carcinogenesis. The relation between the carcinogenesis of uterine cervix or nasopharynx and WC or HHPA extracts is discussed.  相似文献   
142.
143.
144.
Though distressing and potentially dangerous, sleep apnea may be an under-recognized disease in many countries. The obstructive type, which usually presents with loud snoring and excessive daytime sleepiness, is by far the commonest form. It causes a great deal of medical, social and psychological morbidity as well as an increased mortality. Doctors of different specialties have an important role in detecting and referring suspected patients for early assessment and treatment. Multidisciplinary management in a general hospital and accurate assessment with polysomnography are essential as modern and sometimes effective methods of treatment are becoming available.  相似文献   
145.
郑丽英  徐红英  陈华庆 《护理研究》2007,21(17):1568-1569
重睑成形术是眼睑美容手术之一。随着人民生活水平的提高,要求美容的人也越来越多[1]。由于该手术大部分需要切开剥离,去除眼轮匝肌或去脂去皮,容易引起皮下组织水肿、淤血,影响恢复和术后效果。2005年11月—2006年11月,笔者对124例重睑受术者进行术中冰生理盐水冷敷,在减轻水肿、淤血程度、缩短恢复期方面疗效显著。现报道如下。1资料与方法1.1临床资料本组共124例,其中女118例,男6例,年龄20岁~58岁。将受术者按手术时间先后顺序随机分为实验组和对照组各62例。1.2方法两组均使用电凝止血,5-0丝线缝合后用无菌纱布包扎伤口,口服5d抗生素。…  相似文献   
146.
在我国卫生资源总体不足和配置不合理。一方面,中国有13亿人口,占世界总人口的22%,而卫生总费用仅占世界卫生总费用的2%。更严重的是另一方面,据卫生部提供的数据,目前全国80%的医疗资源集中在大城市,其中的30%又集中在大医院。每年到大医院就诊的人群,有80%左右是在基层医院即可解决的常见病、多发病。  相似文献   
147.
The effects of localized gamma-irradiation on the in vivo 31P NMR spectra of RIF-1 tumors grown subcutaneously in C3H/HeN mice have been examined before and during the week after treatment. Increases in the ratio of phosphocreatine (PCr) to inorganic phosphate (Pi) and in tumor pH, and decreases in the ratio of Pi to the beta phosphorus resonance of the nucleotide triphosphates (beta NTP) were observed in irradiated tumors. The time course of changes in the 31P spectrum following treatment was the opposite of the pattern during untreated growth, and the magnitude and duration of the changes increased with increasing radiation dose, decreasing clonogenic cell survival and increasing growth delay. To examine the possibility that nontherapeutic systemic effects of the tumor irradiation were responsible for the changes observed, a number of animals bearing two tumors were examined. One tumor on each mouse was selectively irradiated. Changes in tumor volume, Pi/beta NTP, PCr/Pi, the ratio of phosphomonoesters to beta NTP, and tumor pH were all significantly different in the treated compared to the untreated tumor on each animal, indicating that these changes in 31P NMR spectra were a response to radiation therapy and not a systemic response to radiation toxicity.  相似文献   
148.
E S Li 《中华医学杂志》1989,69(11):607-9, 42
The historical review and the necessity of establishment of the Chinese Classification of Diseases (CCD) and Coding System are described. The content, terms used for unified and standardized nomenclatures, coding system including diagnostic terms of traditional Chinese medicine and other codings are introduced. The utility of the CCD system in medical record face sheet management, national native medical statistics, consultative retrieval from terms and codes of diseases, the development and practical trial of ICD-9 CCD is also discussed. Finally, the position and prospect of CCD system in international informatics communication is emphasized.  相似文献   
149.
150.
Serum IgA and IgG functional antibodies and their subclasses to Streptococcus pneumoniae capsular antigen found in two aged‐matched cohorts of children with and without otitis media with effusion The relationship between acute otitis media and otitis media with effusion (OME) is uncertain and the aetiology of OME is multifactorial. Otitis media with effusion may be an inflammatory condition; both bacteria and viral infections could play a part in this inflammation. The four bacteria Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus and Branhamella catarrhalis cause 60% of the infections whereas S. pneumoniae accounts for up to 35%. IgA provides the dominant surface response to polysaccharide and lipopolysaccharide antigens, of which IgA2 is the main subclass. Once the mucosa has been breached, most protection is provided by IgG. IgG2 acts mainly against bacterial capsular antigens. This study looked at two groups of 50 children with and without OME who were aged between 3 and 10 years. The aims were to determine if, firstly, the levels of the serum immunoglobulins were different in the two groups, secondly whether these children made the appropriate antibody response to the capsular antigen to S. pneumoniae (PCP), and finally if there was a delay in the maturity of the IgA response. The total IgG, IgA and all subclass levels were measured using radial immunodiffusion. Levels of functional IgA and IgG were measured using ELISAs (25 patients in each group). The results were analysed with non‐parametric tests. The immunoglobulin levels were within the normal levels for both groups. There were very good correlations between the IgG total anti‐PCP and the IgG2 anti‐PCP (R > 0.9, p = 0.001). There was a good correlation between the levels of both IgG total and IgG2 anti‐PCP against IgA total anti‐PCP in both groups (R > 0.85, p > 0.01). This confirms a normal antibody response between both groups of patients. The ages of the controls and patients (50 samples) were correlated with increasing titres of circulating functional antibodies (P = 0.001). This is highly suggestive of a normal age‐related response. In conclusion, the findings were contradictory to our original hypothesis that there is a subtle difference in surface protection between children with and without OME. We believe that a previous history of recurrent acute otitis media is unrelated to the development of OME after 3 years of age.  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