全文获取类型
收费全文 | 1252篇 |
免费 | 85篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 62篇 |
妇产科学 | 15篇 |
基础医学 | 148篇 |
口腔科学 | 16篇 |
临床医学 | 138篇 |
内科学 | 249篇 |
皮肤病学 | 19篇 |
神经病学 | 57篇 |
特种医学 | 185篇 |
外科学 | 139篇 |
综合类 | 112篇 |
预防医学 | 70篇 |
眼科学 | 2篇 |
药学 | 64篇 |
中国医学 | 2篇 |
肿瘤学 | 56篇 |
出版年
2022年 | 11篇 |
2021年 | 15篇 |
2020年 | 8篇 |
2019年 | 15篇 |
2018年 | 13篇 |
2017年 | 15篇 |
2016年 | 20篇 |
2015年 | 20篇 |
2014年 | 34篇 |
2013年 | 36篇 |
2012年 | 56篇 |
2011年 | 53篇 |
2010年 | 47篇 |
2009年 | 48篇 |
2008年 | 56篇 |
2007年 | 53篇 |
2006年 | 50篇 |
2005年 | 39篇 |
2004年 | 33篇 |
2003年 | 38篇 |
2002年 | 27篇 |
2001年 | 38篇 |
2000年 | 20篇 |
1999年 | 33篇 |
1998年 | 50篇 |
1997年 | 47篇 |
1996年 | 40篇 |
1995年 | 26篇 |
1994年 | 32篇 |
1993年 | 23篇 |
1992年 | 26篇 |
1991年 | 16篇 |
1990年 | 11篇 |
1989年 | 19篇 |
1988年 | 22篇 |
1987年 | 37篇 |
1986年 | 20篇 |
1985年 | 24篇 |
1984年 | 10篇 |
1983年 | 14篇 |
1982年 | 17篇 |
1981年 | 10篇 |
1980年 | 12篇 |
1979年 | 7篇 |
1978年 | 18篇 |
1976年 | 16篇 |
1975年 | 10篇 |
1971年 | 7篇 |
1970年 | 7篇 |
1969年 | 6篇 |
排序方式: 共有1352条查询结果,搜索用时 15 毫秒
1.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
2.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
3.
The authors investigated whether graduating students' specialty choices were influenced by favorable faculty evaluations and mini-Board scores during their third-year clerkships, and if so, whether the influences were gender-specific. Data were collected from a total of 53 students in two classes, 1988-89 and 1988-90. Univariate and multivariate tests were performed, and the results were analyzed between each class group and between genders in both groups. These results also were compared with information about the students gathered before they matriculated. In general, the results showed a gender-specific correlation: for each rotation where the women's faculty evaluations were significantly higher than the men's, the women subsequently outnumbered the men in choosing that rotation's specialty. Conversely, for each rotation where the men's mini-Board scores were significantly higher than the women's, the men outnumbered the women in choosing that rotation's specialty. The most notable difference was in pediatrics: 8% of the women had indicated an interest in that specialty on the prematriculation questionnaire, while almost one-third of the women in the classes of 1990 and 1991 chose pediatrics residencies. These findings suggest that the favorable scores and evaluations may be one of the influences for students' specialty choices, and that their influence may be gender-specific. 相似文献
4.
5.
6.
R G Roetzheim D J Van Durme H J Brownlee A H Herold R J Pamies L Woodard 《The Journal of the Florida Medical Association》1991,78(7):426-429
A survey of primary care physicians in the greater Tampa Bay metropolitan area was conducted to determine compliance with screening mammography and associated physician characteristics. Information requested included their age, sex, specialty, and board certification status, and the ages and frequencies that they recommend screening mammography for their patients. A total of 565 physicians responded. Even though 88% indicated they follow American Cancer Society recommendations when advising screening mammography, only 62% were actually in full compliance. A significantly greater percentage of obstetricians/gynecologists were compliant (74%) compared to other specialties (family practice, 57%, p = .006; internal medicine, 56%, p = .007; general practice, 53%, p = .003). Women physicians were more likely to be compliant than men (83% versus 58%, p less than .001), and younger physicians more likely than older physicians (72% versus 49%, p less than .001). There was no significant difference in compliance rates between board certified and noncertified physicians. 相似文献
7.
8.
Narrative and procedural discourse in temporal lobe epilepsy. 总被引:2,自引:0,他引:2
Brian Bell Christian Dow E Ryann Watson Austin Woodard Bruce Hermann Michael Seidenberg 《Journal of the International Neuropsychological Society》2003,9(5):733-739
It is well established that some individuals with temporal lobe epilepsy (TLE) demonstrate language deficits at the single word level. However, discourse production rarely has been examined quantitatively within this group. This study compared adult TLE patients with an early seizure onset (< or = age 14 years, n = 27) to a control group (n = 28) on narrative and procedural discourse tasks. As a group, the TLE patients performed normally on the procedural discourse task, but differed significantly from the controls on several narrative discourse variables. At the individual level, 30% of the TLE patients versus 4% of the controls demonstrated impaired discourse ability (p and 0.01). Within this early onset TLE group, discourse performance was not associated with demographic or seizure history variables. Considering the cognitive domain, discourse performance correlated significantly with working memory. In summary, mild discourse dysfunction was present in a significant minority of early onset TLE patients, but this deficit was not closely associated with other language measures. Discourse ability and its neuropsychological, neuroanatomical and conversational speech correlates deserve further study in TLE patients. 相似文献
9.
Previous studies have indicated that the combination of single photon emission computed tomography (SPECT) and quantitative "bull's eye" analysis (QBA) TI-201 cardiac stress imaging may improve the detection of myocardial ischemia over that achieved with planar (PLN) imaging. This study will evaluate the sensitivity and specificity of SPECT and QBA in the detection of disease in the left anterior descending (LAD), left circumflex (LCX), and right coronary artery. Ninety-nine patients who underwent both TI-201 stress imaging and coronary arteriography were evaluated retrospectively. Of the 99, 62 had PLN imaging and 37 were evaluated with SPECT; 23 of these 37 had QBA. The overall sensitivity and specificity were as follows: PLN, 94% and 50%; SPECT, 90% and 67%; QBA, 100% and 20%; and SPECT with QBA, 92% and 72%, respectively. The regional sensitivity and specificity of PLN for individual coronary arteries were as follows: RCA, 78% and 74%; LAD, 89% and 60%; LCX, 50% and 89%, respectively. For SPECT, the results were: RCA, 86% and 93%; LAD, 85% and 88%; and LCX, 60% and 88%. For QBA alone, the results were: RCA, 100% and 75%; LAD, 88% and 53%; and LCX, 100% and 89%. The results for QBA with SPECT were: RCA, 100% and 94%; LAD, 88% and 80%; and LCX, 67% and 95%. Thus, SPECT interpreted on conjunction with QBA showed higher sensitivity for evaluation of ischemia in the RCA and LCX arteries and higher specificity in the detection of LAD and RCA disease than did PLN TI-201 imaging. Because of the low specificity of QBA (20%), caution is advised in the interpretation of QBA alone without reviewing SPECT images. 相似文献
10.
Female Sprague-Dawley rats weighing 45-55 g fed a purified diet for 18 days developed hydroxyapatite intratubular lithiasis, the earliest calcific lesions being detectable by light microscopy on Day 12. The kidneys from these rats revealed ultrastructural changes in proximal tubular cells prior to intraluminal microlith formation. These changes included evidence for increased intracellular calcium, accumulation of electron-dense cytoplasmic granules, and vesiculation and shedding of brush border microvilli within Segment I of the proximal tubule. It was concluded, on the basis of ultrastructural observation, that microvesicles were formed by the shedding of vesiculated microvilli and microvesicles initiated the formation of an intraluminal microurolith in Segment I of the proximal tubule. The initially formed microurolith grew, as it traveled down the nephron, to a size large enough to be visualized by light microscopy. When it reached Segment III (straight segment) of the proximal tubule, the microurolith reached a size so large that it became difficult for it to pass the loop of Henle. 相似文献