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   3677篇
  免费   370篇
  国内免费   59篇
耳鼻咽喉   144篇
儿科学   296篇
妇产科学   13篇
基础医学   419篇
口腔科学   23篇
临床医学   562篇
内科学   204篇
皮肤病学   3篇
神经病学   1111篇
特种医学   53篇
外科学   97篇
综合类   490篇
一般理论   4篇
预防医学   483篇
眼科学   10篇
药学   84篇
  4篇
中国医学   82篇
肿瘤学   24篇
  2024年   16篇
  2023年   91篇
  2022年   69篇
  2021年   189篇
  2020年   158篇
  2019年   161篇
  2018年   176篇
  2017年   169篇
  2016年   161篇
  2015年   173篇
  2014年   233篇
  2013年   526篇
  2012年   217篇
  2011年   189篇
  2010年   132篇
  2009年   162篇
  2008年   161篇
  2007年   152篇
  2006年   163篇
  2005年   126篇
  2004年   98篇
  2003年   91篇
  2002年   75篇
  2001年   60篇
  2000年   66篇
  1999年   31篇
  1998年   34篇
  1997年   35篇
  1996年   24篇
  1995年   21篇
  1994年   19篇
  1993年   19篇
  1992年   8篇
  1991年   15篇
  1990年   10篇
  1989年   10篇
  1988年   9篇
  1987年   6篇
  1986年   3篇
  1985年   9篇
  1984年   7篇
  1983年   7篇
  1982年   7篇
  1981年   3篇
  1980年   4篇
  1977年   1篇
  1976年   1篇
  1975年   2篇
  1974年   1篇
  1973年   5篇
排序方式: 共有4106条查询结果,搜索用时 31 毫秒
1.
2.
3.
ObjectivesThis document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs.Material and methodsThe recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence.ResultsEight tests of speech audiometry in noise can be used in France.ConclusionTo be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other).  相似文献   
4.
目的应用BOLD-MfRI研究正常人及脑肿瘤患者听觉性中英文语言皮层定位并探讨其对脑肿瘤的临床应用价值。方法应用MarconiEclipse1.5T超导型磁共振机,30例受试者,行听觉性中、英文语言刺激的BOLD-MfRI,以定位正常人和脑肿瘤患者的语言皮层。结果正常人听觉性中英文语言任务激活区域均以左侧大脑半球为主,主要有双侧颞横回、Wernicke区、Broca区和SMA区。中文语言任务刺激时脑区激活面积和程度比英文语言任务大,但英文语言任务时可见更明显的Broca区和角回激活。累及功能皮层的脑肿瘤患者患侧半球可见残留部分功能激活区,但激活区移位,分布弥散,激活程度及范围较正常人略增高。未累及功能皮层者功能区定位与正常人大致相同。结论BOLD-MfRI是一种有效而无创的功能皮层定位方法,有利于脑肿瘤的精确定位诊断并指导临床治疗。  相似文献   
5.
大学英语第一册第三课《礼物》是一篇故事短文 ,文中语言简单 ,词汇量少。学生能够在没有教师的指导下掌握文章的主要内容 ,但这并不意味着读懂该篇文章。对文本作深层的理解 ,掌握作者的写作目的 ,是大学英语精读的学习目的和要求。如何帮助学生达到对文本的真正的理解 ,这是一个一直来值得我们研究的问题。针对该文的简洁语体 ,笔者试着从文体学角度进行分析 ,在实际教学过程中 ,取得了较好的效果。在一定程度上提高了学生语篇理解和鉴赏能力。笔者试从文体语言、文体结构和修辞手段三方面分析该文的文体结构。1 文体语言1 .1 故事叙述…  相似文献   
6.
This study re-explored the nature of verbal short-term memory (STM) deficits in children with specific language impairment (SLI), by distinguishing item and serial order STM processes. Recent studies have shown serial order STM capacity to be a critical determinant of language development, relative to item STM. In Experiment 1, 12 children with SLI, 12 age-matched children and 12 language-matched children were administered serial order recognition and reconstruction tasks. Experiment 2 assessed implicit serial learning abilities via a Hebb learning task. The SLI group showed impaired performance for the serial order reconstruction and recognition tasks, relative to language-matched and/or age-matched control groups. However, normal serial position effects were observed in all SLI children in the serial order reconstruction task, suggesting normal coding of serial position information. Similarly, performance on the Hebb serial learning task was at chronological age appropriate levels. Experiment 3 showed that the group differences observed for the serial order STM tasks in Experiment 1 disappeared when the SLI group was compared to a mental age-matched control group. Experiment 4 showed similar performance levels in the SLI group and the mental age-matched control group for a nonword recognition task assessing item STM capacities. This study shows that children with SLI have no specific impairments for serial order and item STM components but that poorer general cognitive efficiency is related to functional limitations in verbal STM tasks. The data are in line with limited information processing accounts of SLI.  相似文献   
7.
As our world becomes increasingly multicultural in nature, multilingual skills constitute an everyday phenomenon in schools. Since most of the second-language research has focused on school-age students, more research had to be conducted with language-minority students at the kindergarten level in order for psychologists and educators to develop effective and efficient systems for evaluating and tracking the developmental status of young language-minority children. The purpose of this study was to investigate the potential usefulness of a standardized continuous progress measure, the Picture Naming Individual Growth and Development Indicator, to longitudinally assess language development in 23 language-minority children, as well as in 13 native English-speaking children. Results indicated that we could use the Picture Naming Individual Growth and Development Indicator to detect differences in first-language and second-language development in language-minority children, as well as to detect differences between the two groups of children in their expressive English-language skills.  相似文献   
8.
Rasmussen and Milner [N.Y. Acad. Sci. Vol. 299, pp. 355–379, 1977] published data on late-lesioned (after age 6) epileptic patients who had suffered left hemisphere lesions. They estimated that left hemisphere dominance occurred in 96% of dextrals and 70% of sinistrals. These figures have been regarded as valid estimates for normal dextrals and sinistrals. We administered the Bilateral Object Naming Latency Task, a verbal tachistoscopic task with very good psychometric properties, to 188 dextral and 72 sinistral normals. Results showed that 93.6% of the dextrals and 80.3% of the sinistrals were left hemisphere dominant. A consideration of results from a number of carefully conducted dichotic listening studies suggests, as do present results, that the 70% left-dominance estimate of Rasmussen and Milner for normal sinistrals may be too low by about 10%. It is suggested that ‘bilateral dominance’, present in 15% of the epileptic sinistrals of Rasmussen and Milner, may be much less common in normal sinistrals.  相似文献   
9.
10.
The planum temporale is a triangular region on the upper surface of the temporal lobe. This area of the brain is important for language processing and shows a left-right asymmetry of size in most brains. Particular interest has been focused on the size and asymmetry of the planum temporale in brains of individuals with developmental dyslexia. Magnetic resonance imaging (MRI) is a method that produces excellent morphological details of organic structures. We have developed an MRI method of studying the size and asymmetry of the planum temporale in human brains. Because of considerable variation of anatomical landmarks in this cortical region of the brain, an evaluation of asymmetry is not possible in all brains. Furthermore, our experience with this method indicates that any indirect imaging technique of studying asymmetry of the planum temporale must be evaluated with caution. With this in mind, however, MRI may give valuable anatomical information about the planum temporale in individuals with anomalous language function.  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