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   342794篇
  免费   22281篇
  国内免费   7627篇
耳鼻咽喉   4071篇
儿科学   9574篇
妇产科学   7393篇
基础医学   27814篇
口腔科学   8070篇
临床医学   37609篇
内科学   42647篇
皮肤病学   4576篇
神经病学   19407篇
特种医学   7865篇
外国民族医学   31篇
外科学   36509篇
综合类   51292篇
现状与发展   12篇
一般理论   29篇
预防医学   35482篇
眼科学   5293篇
药学   30375篇
  395篇
中国医学   30731篇
肿瘤学   13527篇
  2023年   5510篇
  2022年   9755篇
  2021年   13324篇
  2020年   12416篇
  2019年   18171篇
  2018年   15881篇
  2017年   12797篇
  2016年   10336篇
  2015年   9673篇
  2014年   19817篇
  2013年   21515篇
  2012年   18234篇
  2011年   19770篇
  2010年   15888篇
  2009年   14589篇
  2008年   14214篇
  2007年   14694篇
  2006年   12805篇
  2005年   11133篇
  2004年   9097篇
  2003年   7982篇
  2002年   6291篇
  2001年   5628篇
  2000年   4654篇
  1999年   4041篇
  1998年   3273篇
  1997年   3111篇
  1996年   2701篇
  1995年   2595篇
  1994年   2504篇
  1993年   1993篇
  1992年   2022篇
  1991年   1750篇
  1990年   1555篇
  1989年   1382篇
  1988年   1318篇
  1987年   1135篇
  1985年   3792篇
  1984年   4803篇
  1983年   3346篇
  1982年   3803篇
  1981年   3556篇
  1980年   3162篇
  1979年   2909篇
  1978年   2535篇
  1977年   1908篇
  1976年   2153篇
  1975年   1631篇
  1974年   1429篇
  1973年   1279篇
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
81.
目的:分析T1期(肿瘤直径<2cm)原发性乳腺癌女性患者绝经前后在肿瘤大小、病理分类、淋巴结转移率和数目。方法:常规病理检验以及应用免疫组化、HE法分别测定绝经前乳腺癌患者和绝经后乳腺癌患者者的ER、PR。结果:两组患者在肿瘤大小上无明显差异,但绝经前乳腺癌患者浸润导管癌的百分比为 84. 7%,绝经后乳腺癌患者的浸润导管癌百分比为 62. 2%,经χ2 检验,P<0. 01。两组淋巴结转移率分别为 39. 3%和 25. 5%,经χ2 检验,P<0. 01。两组ER和PR阳性伴淋巴结转移的比例经χ2 检验,P<0. 05。结论:绝经前乳腺癌患者和绝经后乳腺癌患者在病理分类、淋巴结转移率及数目、ER、PR阳性伴淋巴结转移上有显著性差异。对于T1原发性乳腺癌患者不论有无淋巴结转移,均应行癌肿切除伴Ⅰ、Ⅱ级淋巴结清扫。  相似文献   
82.
特殊部位异位妊娠的临床分析   总被引:1,自引:0,他引:1  
目的探讨特殊部位异位妊娠的临床特点,误诊原因及治疗原则。方法对1996年1月至2003年12月诊治的256例特殊部位异位妊娠进行回顾性分析。结果特殊部位异位妊娠发生率占同期异位妊娠的3.36%,术前诊断率48.4%,所有的患者均行手术。视术中情况进行不同的处理,所得标本均经病理切片证实,全部患者愈后良好。结论特殊部位异位妊娠的临床表现不典型,容易漏诊误诊,一旦怀疑本病应尽早住院,及时明确诊断并手术,患者愈后良好。  相似文献   
83.
外伤性延迟性脾破裂的诊断和治疗(附21例报告)   总被引:1,自引:0,他引:1  
目的探讨外伤性延迟性脾破裂的发病规律、临床特点、诊断和治疗方法。方法结合国内外资料及本组病例进行回顾性分析。结果明确诊断16例,误诊为肝破裂2例,宫外孕破裂2例,脾肿瘤1例。21例均手术治疗,行脾切除14例,其中保留副脾2例;脾切除加自体脾组织网膜内移植术3例;脾缝合修补术3例;脾部分切除术1例。死亡1例,原因有就诊晚、失血性休克。结论本病由于腹腔内出血与受伤时间间隔长,容易误诊。诊断除依靠病史、临床表现外,应及时进行腹腔穿刺、B超及CT检查。治疗以脾切除为主,可根据病情、脾破裂的程度以及是否有合并伤等情况采取保脾手术。  相似文献   
84.
落枕是一种冬春季常见病,虽然治疗的方法很多,但往往收不到快速、有效和彻底的效果,本文以个案经验和病例调查为基础,提供一种快速有效的自我治疗方法,并期望能够得到广大患者的进一步验证。  相似文献   
85.
For several genetic diseases two biological phenomena have been recognised as important: germline mosaicism; and different new mutation rates in males and females depending on mutation type. Both principles have been investigated separately and their influence on risk estimation in families has been exemplified in the literature. The aim of this paper is to present a general model that includes mosaicism and different new mutation rates. Mosaicism is introduced by defining additional alleles at the disease locus in combination with adapted segregation rules. Taking Duchenne muscular dystrophy as an example, we derive the conditions which have to be fulfilled for a population in mutation selection equilibrium. Our approach describes the model at the population level and not in individual subjects. This has the advantage of being able to use well known algorithms for the calculation of likelihoods in pedigrees, and to include additional diagnostic information such as marker genotypes and carrier deletion test results. We demonstrate the impact of the new model on a typical pedigree. In families where the patient is not available, the distinction between point mutations and deletions is important, since often molecular diagnostic tests for females can only screen for deletions. Negative deletion test results can now be included in the risk calculations.  相似文献   
86.
87.
Objectives –  To assess long‐term functioning and disability after traumatic brain injury (TBI). Material and methods –  Individuals (n = 88) in Norrbotten, northern Sweden, who had been transferred for neurosurgical care were assessed with internationally established TBI outcome measures 6–15 years post‐injury. Results –  There was an improvement in overall outcome from discharge from inpatient rehabilitation to follow‐up. Many individuals had a high degree of motor and cognitive functioning, which enabled them to live independently in their own home without assistance, but there remained a disability related to community reintegration and social participation. This affected their productivity and to some degree their marital stability. The remaining disability and reduced productivity were related to the age at injury and the injury severity. Conclusions –  Our data showed that individuals with a TBI can achieve and maintain a high degree of functioning many years after the injury. Increasing age and a greater injury severity contributed to their long‐term disability.  相似文献   
88.
89.
90.
While much time has been spent deliberating about the definition of play, little emphasis has been placed on what children themselves perceive as play. The aim of the present study was to examine social context as a cue for children's perceptions of play and learning. Ninety-two children aged between four and six years (mean four years nine months) participated in the study and completed the Activity Apperception Story Procedure. Children were asked to sort photographic stimuli into those they believed depicted play/not play and learning/not learning. Each of the stimuli were identified by independent raters as containing one of the following social cues; teacher absence (solitary activity, parallel activity or cooperative activity) or teacher presence (teacher involved activity or teacher directed activity). Findings revealed that children associated teacher absence with play. More specifically, children made links between play and the presence of peers (parallel and cooperative activity). Findings are discussed in relation to play in the early years curriculum, differences in children's early educational experiences and the importance of understanding children's perceptions of play.  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