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   1265篇
  免费   55篇
  国内免费   6篇
耳鼻咽喉   13篇
儿科学   29篇
妇产科学   51篇
基础医学   192篇
口腔科学   22篇
临床医学   88篇
内科学   265篇
皮肤病学   29篇
神经病学   157篇
特种医学   36篇
外科学   96篇
综合类   1篇
预防医学   101篇
眼科学   13篇
药学   90篇
中国医学   8篇
肿瘤学   135篇
  2023年   11篇
  2022年   44篇
  2021年   49篇
  2020年   16篇
  2019年   27篇
  2018年   49篇
  2017年   35篇
  2016年   36篇
  2015年   45篇
  2014年   63篇
  2013年   67篇
  2012年   111篇
  2011年   111篇
  2010年   63篇
  2009年   48篇
  2008年   86篇
  2007年   64篇
  2006年   81篇
  2005年   71篇
  2004年   60篇
  2003年   49篇
  2002年   37篇
  2001年   12篇
  2000年   7篇
  1999年   4篇
  1998年   9篇
  1997年   5篇
  1996年   6篇
  1995年   5篇
  1994年   5篇
  1993年   3篇
  1992年   2篇
  1990年   2篇
  1988年   4篇
  1987年   2篇
  1986年   3篇
  1984年   3篇
  1983年   5篇
  1982年   3篇
  1980年   1篇
  1978年   2篇
  1977年   1篇
  1975年   2篇
  1974年   2篇
  1973年   2篇
  1972年   3篇
  1971年   1篇
  1967年   1篇
  1966年   4篇
  1965年   1篇
排序方式: 共有1326条查询结果,搜索用时 15 毫秒
31.
The well-known classification of neuroendocrine neoplasms of the lung into four major subtypes (including typical and atypical carcinoids and small- and large-cell neuroendocrine carcinomas) has a proven prognostic validity but only partially helps to predict the response to specific therapies. Therapeutic biomarkers are incompletely known and include morphological, immunophenotypic, and molecular markers. Morphology alone has no specific predictive role, nor has any immunophenotypic marker been proven to bear predictive implications. Ki67 is a relevant prognostic marker and can indirectly predict response to chemotherapy, when levels are extremely high in high-grade neuroendocrine (NE) carcinomas. The expression of somatostatin receptors, especially of the type 2A, has been shown to predict response to somatostatin analog treatments, paralleling the information derived from octreotide scintigraphy. mTOR pathway is targeted by specific inhibitors, but the exact cellular molecules predicting response are still to be defined. It seems that high levels of phosphorylated forms of mTOR and of its downstream factor S6K are associated to a better response to rapalogs in experimental models. Data from gene expression profiling and mutational analyses are currently emerging, providing a more detailed map of different molecular activation pathways, potentially leading to a more accurate molecular classification of lung NE tumors as well as to the discovery of new therapeutic targets. The combination of mutational profiles with those of upregulated or downregulated genes also by gene gains or losses may ultimately provide a better characterization of NE tumor histological types in terms of response to specific chemotherapy or biotherapy.  相似文献   
32.

Purpose

This study was conducted to prospectively investigate the interobserver reproducibility of controlled attenuation parameter (CAP) measurements and the relationship among the CAP and body mass index (BMI), gender and age.

Methods

Consecutive subjects were studied using the M+ probe of the FibroScan device (Echosens, Paris, France). Measurements were performed by two raters (rater1 and rater2). Interobserver agreement was assessed by using the concordance correlation coefficient (CCC). The Pearson r coefficient was used to test correlation between two study variables, and linear regression was used for the multivariate model.

Results

Three hundred fifty-one subjects (227 males and 124 females) were prospectively studied. The CCC was 0.82 (95 % CI 0.78–0.85) overall, 0.80 (95 % CI 0.75–0.85) for BMI <25 kg/m2, 0.76 (95 % CI 0.69–0.84) for BMI 25–29 kg/m2 and 0.65 (95 % CI 0.41–0.88) for BMI ≥30 kg/m2. The CCC was 0.44 (95 % CI 0.31–0.56) for CAP values ≤240 dB/m and 0.72 (95 % CI 0.65–0.79) for CAP values >240 dB/m. In univariate analysis, age and BMI by gender were correlated with the CAP. Multiple regression analysis confirmed the relationship of the CAP with age and BMI, but not with gender.

Conclusions

The results of this study show that the interreader agreement in CAP measurement is good. In healthy volunteers, the CAP is strongly correlated with age and BMI.  相似文献   
33.
34.
35.
PurposeMalposition of the lower lid, including rounding of the lateral canthal angle, lower eyelid retraction with inferior scleral show, and ectropion, is a relatively frequent complication in the surgical treatment of skin cancer of the cheek and zygomatic areas. The tarsal strip technique, in association with a vertical vector cheek lift, is a reliable method for correcting lower lid malposition.Materials and patientsFrom January 2008 to January 2010, we treated 19 patients with lower eyelid malposition after skin cancer surgery of the cheek and zygomatic areas. To correct lower eyelid malposition, we used the tarsal strip technique and a vertical vector cheek lift in all patients.ResultsEleven patients had scleral show and eight patients had ectropion. Sixteen patients obtained satisfactory correction of the eyelid malposition in a single surgical procedure, while three patients required a second surgical step to correct the remaining scleral show. Good esthetic and functional results were achieved in all cases.ConclusionsThe surgical treatment of skin cancer of the cheek and zygomatic areas has the potential for postoperative sequelae. The tarsal strip technique, in association with a vertical vector cheek lift, is a relatively simple technique for correcting scleral show and ectropion.  相似文献   
36.
37.
A deletion of one of the two copies of the 9-bp tandem repeat sequence (CCCCCTCTA), in the small non-coding/untranslated segment located between the cytochrome oxidase II and lysine tRNA genes of mitochondrial DNA (mtDNA), has previously been used as a polymorphic anthropological marker (MIC9D) for people of Africa and Asia, but it has been rarely reported in Europe. 32 Sicilian patients with syndromic hearing loss, negative for mutations in GJB2 and GJB6 genes, were tested for mtDNA known point mutations associated with syndromic or non-syndromic hearing loss by RFLP and/or direct sequencing. We identified the presence of the MIC9D in homoplasmy in lymphocytes and muscle of three subjects with sensorineural hearing loss and encephalomyopathy, two of these also presented moderate mental retardation. This deletion was absent in 300 Caucasian controls. Although further studies are warranted, our results suggest that the MIC9D polymorphism could have a susceptibility role in Caucasus, such as Sicily population.  相似文献   
38.
We evaluated the efficacy of clodronate for treating active erosive osteoarthritis of the hand and to compare it with hydroxychloroquine. Group A consisted of 24 patients treated for 24 months with clodronate 300 mg i.v. for 7 days, followed by clodronate i.m. 100 mg for 14 days every 3 months. Group B comprised 14 patients treated with hydroxychloroquine 400 mg daily for 30 days, followed by 200 mg daily for the next 11 months. In group A, 21/24 patients completed the trial and obtained significant pain reduction (p < 0.001), Dreiser’s score (p = 0.012), and number of tender joints (p = 0.011). Strength of right (p = 0.04) and left (p = 0.016) hands, physician’s global assessment (p ≤ 0.001), and patient’s global assessment (p = 0.021) improved. In group B, 8/14 patients completed 12 months of the study, which showed the inefficacy of hydroxychloroquine and its lack of acceptance by patients (worsening pain and patient’s global assessment). Therefore, enrolment was stopped. Differences between groups showed a pain decreasing trend for group A and a slightly increasing one for group B (p = 0.018). Physician and patient global assessments showed a strong increase in group A compared with group B (p < 0.001). Clodronate is effective in erosive osteoarthritis; hydroxychloroquine seems to be ineffective.  相似文献   
39.
Pleomorphic xanthoastrocytoma (PXA) is a rare tumor with good prognosis after surgery. Few cases of anaplastic PXA (either de novo or secondary to transformation of a recurrent low grade PXA) have been reported. Moreover, primary anaplastic PXA with dissemination at diagnosis has been described only in two patients, to our knowledge. We report the first case of primary multicentric anaplastic PXA and discuss its atypical features and the pertinent literature.  相似文献   
40.
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