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   8744篇
  免费   531篇
  国内免费   26篇
耳鼻咽喉   126篇
儿科学   276篇
妇产科学   263篇
基础医学   905篇
口腔科学   139篇
临床医学   786篇
内科学   2285篇
皮肤病学   82篇
神经病学   911篇
特种医学   338篇
外科学   941篇
综合类   93篇
一般理论   6篇
预防医学   988篇
眼科学   158篇
药学   570篇
中国医学   2篇
肿瘤学   432篇
  2024年   7篇
  2023年   35篇
  2022年   59篇
  2021年   178篇
  2020年   83篇
  2019年   169篇
  2018年   194篇
  2017年   163篇
  2016年   147篇
  2015年   172篇
  2014年   281篇
  2013年   391篇
  2012年   633篇
  2011年   695篇
  2010年   383篇
  2009年   376篇
  2008年   575篇
  2007年   691篇
  2006年   649篇
  2005年   616篇
  2004年   584篇
  2003年   540篇
  2002年   475篇
  2001年   106篇
  2000年   71篇
  1999年   81篇
  1998年   106篇
  1997年   80篇
  1996年   63篇
  1995年   71篇
  1994年   49篇
  1993年   50篇
  1992年   61篇
  1991年   38篇
  1990年   45篇
  1989年   67篇
  1988年   40篇
  1987年   28篇
  1986年   28篇
  1985年   19篇
  1984年   34篇
  1983年   21篇
  1982年   26篇
  1981年   25篇
  1980年   18篇
  1979年   11篇
  1978年   14篇
  1977年   11篇
  1976年   9篇
  1971年   6篇
排序方式: 共有9301条查询结果,搜索用时 281 毫秒
11.
BACKGROUND: Simple surgical excision is one of the most common treatment methods in the dermatologist's armamentarium. We describe a precise postsurgical dressing technique that can be used for wound care of those patients whose treatment involves removal of lesions via cutaneous surgery. OBJECTIVE: To devise a novel, precise, and effective dressing technique for postsurgical wound care. MATERIALS AND METHODS: We describe the technique using common in-office instruments. RESULTS AND CONCLUSION: Wound dressings for lesions located on curved areas such as the ears, nose, cheeks, and chin often exhibit less than adequate adherence and stability. The kerf-cut dressing technique optimizes pliability of dressing tape, and this maximizes efficient and stable application of postsurgical wound dressings to curved areas of the body.  相似文献   
12.
13.
The effect of estradiol valerate and allylestrenol on the endometrial transformation of five hypergonadotropic hypogonadic women was evaluated. Estradiol valerate was administered throughout the whole induced cycle (28 days), while allylestrenol was added during the second half of the cycle. Endometrial biopsies were performed during allylestrenol treatment and were evaluated histologically. Samples of endometrium were also subjected to one-dimensional SDS electrophoresis. Of ten biopsies performed, only one was interpreted to be in-phase, while the others were dated proliferative (4 biopsies) or showed abortive or out-of-phase secretory transformation. The highest mean serum progesterone level, detected under allylestrenol treatment, was 1.5 ng/ml. Protein electrophoresis demonstrated relative sequential changes in the protein patterns of the 115 kDa and 150 kDa protein bands. It is concluded that allylestrenol, although having gestagen properties, may not be efficient for the induction of an adequate secretory transformation of human endometrium in the absence of ovaries.  相似文献   
14.
Background Health-related quality of life (HRQL) is an accepted outcome measure in patients with mood and anxiety disorders. Yet, surprisingly little attention has been paid to the determinants. In this paper we test the hypothesis that it is associated with personality traits while controlling for mental disorders. Methods A large sample of outpatients (n=640) with mood and anxiety disorders was studied. The empirically supported five factor model of normal personality traits was assessed using the NEO-FFI and includes: neuroticism, extraversion, openness to experience, agreeableness, and conscientiousness. Mental disorders were assessed with the CIDI, and HRQL with the SF-36. Results Regression analyses revealed that the NEO-FFI scores, with the exception of conscientiousness, were significantly associated with SF-36 subscales and summary scores, independently from the mental disorders. The percentage of explained variance due to the personality traits was highest for the subscales Vitality (10.0%), Mental Health (13.3%) and the Mental Health Summary Score (9.5%). Furthermore, specific personality traits were related to specific SF-36 subscales. Conclusions A low HRQL of patients with mood or anxiety disorders is not only determined by the disease or the current health but is also shaped by personality traits that are relatively stable throughout an individual's life time.  相似文献   
15.
16.
17.
18.
19.
OBJECTIVE: One of the main limitations of image-guided surgery is that navigation relies on the use of a CT scan obtained before surgery and is unable to be updated during the procedure. A software addition has been developed to allow reconstruction of CT-like images from a series of fluoroscopic scans and integrate these into an image-guided system (GE Healthcare Surgical Navigation, Lawrence, MA). We report our initial experience with a series of patients undergoing intraoperative fluoroscopic navigation in sinus surgery. STUDY DESIGN AND SETTINGS: After institutional review board clearance, we prospectively studied 14 consecutive patients undergoing image-guided sinus surgery with the use of intraoperative fluoroscopy. RESULTS: All patients had preoperative and postoperative fluoroscopic images reconstructed into CT-like images. By the conclusion of the study, images were adequate in quality and accurate navigation was achieved. CONCLUSION: Real-time image-guided sinus surgery using fluoroscopy is feasible. Future studies will need to focus on defining the procedures that could benefit, such as tumor resection, to enhance patient safety during these operations.  相似文献   
20.
Using in vitro quantitative autoradiography and [125I]Tyr0-D-Trp8SRIF 14 as radioligand, we characterized the detailed distribution of somatostatin binding sites in human hypothalamus of both infants and adults. Guanosine triphosphate pretreatment, before incubation, allowed us to detect higher [125I]Tyr0-D-Trp8SRIF 14 binding site densities in hypothalamic structures such as preoptic and anterior hypothalamic areas and ventromedial and dorsomedial nuclei. In contrast, guanosine triphosphate was without effect in the other hypothalamic regions. The regional effects of guanosine triphosphate pretreatment were not different in infant and adult hypothalamus. Scatchard analysis showed that in a guanosine triphosphate-sensitive region (preoptic area) and a guanosine triphosphate-insensitive area (infundibular nucleus), [125I]Tyr0-D-Trp8SRIF 14 bound to a single class of binding sites. Affinities were similar in both regions, not modified by guanosine triphosphate pretreatment and not different in the adult (1.5 +/- 1.2 nM vs 3.2 +/- 2.1 nM for preoptic area and infundibular nucleus, respectively) and infant (0.9 +/- 0.5 nM vs 2.4 +/- 1.7 nM for preoptic area and infundibular nucleus). [125I]Tyr0-D-Trp8SRIF 14 binding sites were widely distributed in the anterior, mediobasal and posterior hypothalamus. Somatostatin 28 was twice as potent as somatostatin 14 to displace [125I]Tyr0-D-Trp8SRIF 14 binding in the preoptic area and infundibular nucleus. However, IC50s were 30 times lower in the preoptic area as compared with the infundibular nucleus. In adult as well as in infant, high densities were found mainly in the diagonal band of Broca, preoptic area and infundibular nucleus. Intermediate densities were localized in the anterior hypothalamic area, ventromedial, dorsomedial and lateral mammillary nuclei. The dorsal hypothalamic area, the paraventricular and medial mammillary nuclei displayed low but measurable densities. The only marked difference in the distribution of [125I]Tyr0-D-Trp8SRIF 14 binding sites in adult vs infant was observed in the medial and tuberal nuclei where the concentrations were seven-fold higher in adult hypothalamus.  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