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   722篇
  免费   12篇
  国内免费   2篇
  736篇
  2023年   1篇
  2022年   2篇
  2021年   4篇
  2020年   2篇
  2019年   10篇
  2018年   4篇
  2017年   6篇
  2016年   6篇
  2015年   6篇
  2014年   7篇
  2013年   28篇
  2012年   9篇
  2011年   5篇
  2010年   8篇
  2009年   4篇
  2008年   7篇
  2007年   9篇
  2006年   7篇
  2005年   4篇
  2004年   9篇
  2003年   4篇
  2002年   5篇
  2001年   2篇
  2000年   5篇
  1999年   3篇
  1998年   4篇
  1997年   2篇
  1996年   3篇
  1995年   3篇
  1993年   3篇
  1992年   1篇
  1991年   2篇
  1987年   1篇
  1985年   33篇
  1984年   49篇
  1983年   41篇
  1982年   51篇
  1981年   60篇
  1980年   84篇
  1979年   47篇
  1978年   53篇
  1977年   45篇
  1976年   26篇
  1975年   18篇
  1974年   35篇
  1973年   18篇
排序方式: 共有736条查询结果,搜索用时 0 毫秒
161.
In mid‐June 2009, the Obama administration dissolved the President's Council on Bioethics (PCBE), a group established by President George W. Bush in August 2001 and whose nearly eight‐year life was marked from beginning to end by controversy. While some will regret the PCBE's passing, others will regard the Council as a failed experiment in doing public bioethics.  相似文献   
162.
163.
164.
Ultrasound technology has not been used extensively in the study of normal and abnormal oral physiology and speech. Features such as soft tissue detail, real-time motion display, and subject safety make ultrasound ideal for imaging the tongue and the floor of the mouth. This study demonstrates visualization of the muscles of the tongue and floor of the mouth for a normal subject using ultrasound imaging. By employing submandibular transducer placement of real-time sector scanners, tongue anatomy and motion were continuously visualized in sagittal or coronal planes. In addition to the entire tongue surface, much of the intrinsic anatomy was identified including: the genioglossus, geniohyoid, mylohyoid, and digastric muscles; fascial boundaries such as the median fibrous septum, floor intermuscular septum, and paramedian septums; and the hyoid bone. A tongue excised from a human cadaver was scanned using ultrasound and dissected to confirm the anatomy seen in the live tongue. Tongue surface shape and configuration of the intrinsic tissue structures were observed and compared for the phonemes /k/, /u/, and /i/. Anatomical landmarks in the resting and speaking tongue are discussed as well as applications in the fields of speech science and speech pathology.  相似文献   
165.
166.
Seven-year-old children classified as good and poor readers carried out a proofreading task on two passages varying in level of difficulty. Misspellings were introduced by transposing two adjacent letters in the work "the," other three-letter words, and longer words. While both groups of readers were able to identify the correct spelling of the misspelled words on a spelling test, poor readers made significantly more proofreading errors. Word length had a significant effect on performance, indicating that sensitivity to word configuration is important for successful proofreading. The pattern of proofreading errors did not reflect underlying differences which might relate to strategies used by the two groups in normal reading. The results are compared with those from other proofreading and letter detection experiments in order to highlight methodological implications when such tasks are used to verify hypotheses concerned with normal reading strategies.  相似文献   
167.
The role of grammars in models of language use   总被引:1,自引:0,他引:1  
  相似文献   
168.
When third-formant transitions are appropriately incorporated into an acoustic syllable, they provide critical support for the phonetic percepts we call [d] and [g], but when presented in isolation they are perceived as time-varying ‘chirps’. In the present experiment, both modes of perception were made available simultaneously by presenting the third-format transitions to one ear and the remainder of the acoustic syllable to the other. On the speech side of this duplex percept, where the transitions supported the perception of stop-vowel syllables, perception was categorical and influenced by the presence of a preposed [al] or [ar]. On the nonspeech side, where the same transitions were heard as ‘chirps’, perception was continuous and free of influence from the preposed syllables. As both differences occurred under conditions in which the acoustic input was constant, we should suppose that they reflect the different properties of auditory and phonetic modes of perception.  相似文献   
169.
170.
A study was designed to tap children's perceptions of the divorce situation as opposed to adults' perceptions of the child's response to the parental divorce. Subjects were 75 boys and 75 girls from mother- and father-headed families. Using an individual structured interview procedure children were encouraged to reconstruct both positive and negative dimensions of their interactions with the custodial parent. Through factor analyses of the contents of interviews four negative and two positive factors involving 20 specific items were identified in the children's perceptual data. Subsequently, chi-square analyses were done to compare differences in girls' and boys' perceptions between and across father- and mother-headed families. Results are discussed in terms of their relationship with the existing literature and their clinical and educational relevance to children, single parents and professionals.  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