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   6649篇
  免费   423篇
  国内免费   41篇
耳鼻咽喉   110篇
儿科学   206篇
妇产科学   119篇
基础医学   925篇
口腔科学   443篇
临床医学   512篇
内科学   1377篇
皮肤病学   163篇
神经病学   463篇
特种医学   252篇
外科学   899篇
综合类   33篇
一般理论   2篇
预防医学   646篇
眼科学   205篇
药学   406篇
中国医学   48篇
肿瘤学   304篇
  2023年   43篇
  2022年   106篇
  2021年   198篇
  2020年   128篇
  2019年   164篇
  2018年   213篇
  2017年   159篇
  2016年   175篇
  2015年   207篇
  2014年   279篇
  2013年   326篇
  2012年   483篇
  2011年   459篇
  2010年   295篇
  2009年   222篇
  2008年   331篇
  2007年   334篇
  2006年   317篇
  2005年   295篇
  2004年   284篇
  2003年   271篇
  2002年   183篇
  2001年   144篇
  2000年   143篇
  1999年   133篇
  1998年   68篇
  1997年   61篇
  1996年   59篇
  1995年   62篇
  1994年   38篇
  1993年   42篇
  1992年   80篇
  1991年   73篇
  1990年   80篇
  1989年   60篇
  1988年   75篇
  1987年   69篇
  1986年   58篇
  1985年   61篇
  1984年   34篇
  1983年   26篇
  1982年   24篇
  1981年   17篇
  1980年   18篇
  1979年   22篇
  1978年   15篇
  1977年   15篇
  1975年   20篇
  1973年   16篇
  1972年   16篇
排序方式: 共有7113条查询结果,搜索用时 15 毫秒
91.
92.
Background and aimsWe aimed to analyze the relationship between the initial chest X-ray findings in patients with severe acute respiratory syndrome due to infection with SARS-CoV-2 and eventual clinical worsening and to compare three systems of quantifying these findings.Material and methodsThis retrospective study reviewed the clinical and radiological evolution of 265 adult patients with COVID-19 attended at our center between March 2020 and April 2020. We recorded data related to patients’ comorbidities, hospital stay, and clinical worsening (admission to the ICU, intubation, and death). We used three scoring systems taking into consideration 6 or 8 lung fields (designated 6 A, 6 B, and 8) to quantify lung involvement in each patient's initial abnormal chest X-ray and to classify its severity as mild, moderate, or severe, and we compared these three systems. We also recorded the presence of alveolar opacities and linear opacities (fundamentally linear atelectasis) in the first chest X-ray with pathologic findings.ResultsIn the χ2 analysis, moderate or severe involvement in the three classification systems correlated with hospital admission (p = 0.009 in 6 A, p = 0.001 in 6 B, and p = 0.001 in 8) and with death (p = 0.02 in 6 A, p = 0.01 in 6 B, and p = 0.006 in 8). In the regression analysis, the most significant associations were 6 B with alveolar involvement (OR 2.3; 95%CI 1.1.–4.7; p = 0.025;) and 8 with alveolar involvement (OR 2.07; 95% CI 1.01.–4.25; p = 0.046). No differences were observed in the ability of the three systems to predict clinical worsening by classifications of involvement in chest X-rays as moderate or severe.ConclusionModerate/severe extension in the three chest X-ray scoring systems evaluating the extent of involvement over 6 or 8 lung fields and the finding of alveolar opacities in the first abnormal X-ray correlated with mortality and the rate of hospitalization in the patients studied. No significant difference was found in the predictive ability of the three classification systems proposed.  相似文献   
93.
94.
95.
96.
Sweet's syndrome, or febrile neutrophilic dermatosis, is a process characterized by fever, red tender plaques, neutrophilia and neutrophilic dermal infiltrate with papilar edema in the absence of vasculitis. The association with intestinal inflammatory disease is inusual, a new case associated with ulcerative colitis is reported, and we perform a literature review of Sweet's associated intestinal inflammatory disease.  相似文献   
97.
Adult and pediatric laryngotracheal stenoses (LTS) comprise a wide array of various conditions that require precise preoperative assessment and classification to improve comparison of different therapeutic modalities in a matched series of patients. This consensus paper of the European Laryngological Society proposes a five-step endoscopic airway assessment and a standardized reporting system to better differentiate fresh, incipient from mature, cicatricial LTSs, simple one-level from complex multilevel LTSs and finally “healthy” from “severely morbid” patients. The proposed scoring system, which integrates all of these parameters, may be used to help define different groups of LTS patients, choose the best treatment modality for each individual patient and assess distinct post-treatment outcomes accordingly.  相似文献   
98.
99.
We evaluated the monthly distribution of rotavirus diarrhea in a cohort of children 12–24 months of age followed as part of a diarrhea clinical trial in a peri-urban community of Lima. We observed a peak of rotavirus diarrhea in the winter months and a decrease in rotavirus prevalence after the introduction of the rotavirus vaccine in Peru.  相似文献   
100.

Purpose

To evaluate the clinical outcome of a cohort of localized prostate cancer patients treate with 125-I permanent brachytherapy at the São José Hospital – CHLC, Lisbon.

Materials and Methods

A retrospective analysis was carried out on 429 patients with low and intermediate-risk of prostate adenocarcinoma, according to the recommendations of the EORTC, who underwent 125I brachytherapies in intraoperative dosimetry “real-time” system between September 2003 and September 2013.

Results

The mean follow-up was 71.98 months. Biochemical relapse of disease by rising PSA (Phoenix criterion) was observed in 18 patients (4.2%). Through the application of Kaplan-Meier survival curves in this sample, the rate of survival at 6 years without biochemical relapse was higher than 95%. By Iog rank test comparing biochemical relapse with initial PSA (15-10 and <10) and Gleason values (7 and <7), there was no statistical difference (P=0.830) of the initial PSA in the probability of developing biochemical relapse. In relation to Gleason score, it was noted a statistical difference (P<0.05), demonstrating that patients with Gleason 7 are more likely to develop biochemical relapse.

Conclusions

Brachytherapy as monotherapy is at present an effective choice in the treatment of localized prostate adenocarcinoma. Biochemical relapses are minimal. The initial PSA showed no statistically difference in the rate of relapses, unlike the value Gleason, where it was demonstrated that patients with Gleason 7 have a higher probability of biochemical relapse. Cases with PSA bounce should be controlled before starting a salvage treatment.  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