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   12516篇
  免费   1100篇
  国内免费   49篇
耳鼻咽喉   145篇
儿科学   361篇
妇产科学   308篇
基础医学   1642篇
口腔科学   379篇
临床医学   1993篇
内科学   2392篇
皮肤病学   242篇
神经病学   1091篇
特种医学   390篇
外国民族医学   1篇
外科学   1961篇
综合类   376篇
一般理论   17篇
预防医学   941篇
眼科学   182篇
药学   640篇
中国医学   5篇
肿瘤学   599篇
  2023年   52篇
  2022年   75篇
  2021年   155篇
  2020年   125篇
  2019年   166篇
  2018年   230篇
  2017年   154篇
  2016年   174篇
  2015年   193篇
  2014年   284篇
  2013年   433篇
  2012年   657篇
  2011年   668篇
  2010年   402篇
  2009年   342篇
  2008年   610篇
  2007年   584篇
  2006年   546篇
  2005年   572篇
  2004年   538篇
  2003年   487篇
  2002年   436篇
  2001年   482篇
  2000年   505篇
  1999年   424篇
  1998年   238篇
  1997年   215篇
  1996年   203篇
  1995年   184篇
  1994年   148篇
  1993年   153篇
  1992年   277篇
  1991年   272篇
  1990年   255篇
  1989年   263篇
  1988年   223篇
  1987年   201篇
  1986年   192篇
  1985年   180篇
  1984年   157篇
  1983年   110篇
  1982年   78篇
  1981年   66篇
  1980年   56篇
  1979年   100篇
  1978年   60篇
  1976年   63篇
  1974年   67篇
  1972年   65篇
  1971年   51篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
Dickey MW  Thompson CK 《Aphasiology》2007,21(6-8):604-616
BACKGROUND: Production of grammatical morphology is typically impaired in agrammatic aphasic individuals, as is their capacity to produce the syntactic structure responsible for licensing that morphology. Whether these two impairments are causally related has been an issue of long-standing debate. If morphological deficits are a side-effect of underlying syntactic ones, as has been claimed (Friedmann & Grodzinsky, 1997; Izvorski & Ullman, 1999), therapy which improves the syntactic deficit should remediate the morphological deficit as well. This paper reports a case study of one individual with such co-occurring impairments and describes their recovery in response to linguistically-motivated treatment targeting his syntactic deficits. METHODS #ENTITYSTARTX00026; PROCEDURES: MD is a 56 year-old male diagnosed with non-fluent Broca's aphasia subsequent to a left-hemisphere CVA, with limited capacity to produce syntactically complex utterances and grammatical morphology. He was enrolled in therapy using Treatment of Underlying Forms (TUF; Thompson & Shapiro, 2005), targeting production of sentences involving Wh-movement (object relative clauses). MD participated in twice-weekly treatment sessions for approximately two months, with daily probes assessing his production of treated and untreated sentence types. In addition, probes assessing his grammatical morphology and sentence production were administered pre- and post-treatment. OUTCOMES #ENTITYSTARTX00026; RESULTS: Pre-treatment scores in tests of grammatical morphology and sentence production indicated deficits in both domains. During treatment, MD successfully acquired production of a variety of sentence with Wh-movement, though this did not generalize to sentences involving a grammatically distinct movement operation (NP-movement). Post-treatment scores also indicated a lack of improvement in production of grammatical morphology. CONCLUSIONS: The dissociation between MD's morphological and syntactic recovery indicates that the recovery of syntactic and morphological processes in aphasia may occur independently. This result is thus surprising under approaches in which morphological and syntactic impairments are strongly and causally related in aphasia, such as the Tree-Pruning Hypothesis (Friedmann, 2001; Friedmann & Grodzinsky, 1997). Further, these results reinforce the conclusion that aphasia treatment can lead to generalization, but only to linguistic material which is in a subset relation to trained structures (Thompson, Shapiro, Kiran & Sobecks, 2003).  相似文献   
22.
23.
24.
25.
26.
27.
Mycotic aneurysms of the abdominal aorta are potentially fatal but uncommon. We report the MRI and MRA features of an abdominal aortic mycotic aneurysm in a patient who presented with nonspecific low back pain. By delineating the saccular nature of the aneurysm and identifying the coexistence of vertebral enhancement, MRI was crucial for the final diagnosis. A potential pitfall of contrast-enhanced MRA is also demonstrated.  相似文献   
28.
29.
More accurate noninvasive estimation of prostate size is important in therapeutic trials for benign prostatic hyperplasia. The accuracy of MRI and transrectal ultrasound (TRUS) in assessing prostate weight was evaluated in 48 patients who underwent radical prostatectomy for stage A or B cancer. The volume derived from the wet weight of the freshly excised specimen was used as a reference. We compared that volume with volume estimates derived from the three-axis linear dimension measurement by MRI and TRUS using a tissue density of 1.05 g/cc and the standard formula for an ellipsoid object. Prostate and seminal vesicle volumes were also computed by contouring T2-weighted 5 mm thick contiguous MR images using a semiautomatic edge detection program and pixel summation. Three-axis volume MRI method versus volume from wet weight has slightly less scatter than TRUS three-axis method (r = 0.85 vs r = 0.81). Contoured MR volume method has the least scatter r = 0.93, statistically better than the linear axis method. Contoured MRI volumetric analysis appears superior to linear MRI or TRUS methods in estimating true prostate volume.  相似文献   
30.
A simple method of tissue homogenization with sterile reinforced polyethylene bags for quantitative fungal cultures was evaluated with mice infected with Candida albicans. This new method correlated well with standard methods (P less than or equal to 0.01) for quantifying viable fungus in homogenates of brain, kidney, spleen, liver, and lungs and may be applicable in clinical and experimental mycology laboratories.  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