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   946篇
  免费   52篇
  国内免费   9篇
耳鼻咽喉   33篇
儿科学   27篇
妇产科学   35篇
基础医学   87篇
口腔科学   22篇
临床医学   81篇
内科学   170篇
皮肤病学   33篇
神经病学   104篇
特种医学   42篇
外科学   208篇
综合类   11篇
预防医学   26篇
眼科学   29篇
药学   66篇
肿瘤学   33篇
  2023年   10篇
  2022年   10篇
  2021年   33篇
  2020年   22篇
  2019年   18篇
  2018年   23篇
  2017年   20篇
  2016年   47篇
  2015年   46篇
  2014年   53篇
  2013年   48篇
  2012年   75篇
  2011年   93篇
  2010年   37篇
  2009年   34篇
  2008年   43篇
  2007年   65篇
  2006年   54篇
  2005年   74篇
  2004年   53篇
  2003年   45篇
  2002年   25篇
  2001年   12篇
  2000年   10篇
  1999年   13篇
  1998年   5篇
  1997年   3篇
  1996年   3篇
  1995年   5篇
  1994年   2篇
  1993年   3篇
  1992年   5篇
  1991年   4篇
  1990年   2篇
  1989年   2篇
  1988年   4篇
  1987年   3篇
  1986年   2篇
  1983年   1篇
排序方式: 共有1007条查询结果,搜索用时 15 毫秒
11.
The objective of this study was to investigate the prognostic significance of p53, and proliferative cell nuclear antigen (PCNA) in laryngeal squamous cell carcinoma (LSCC). Sixty pathologic specimens from the patients with LSCC were examined for the expression of the p53 and PCNA, with complete follow-up data. Sixty-three percent of the cases displayed nuclear p53 overexpression. There was a correlation between p53 overexpression and histological grades (p = 0.03), and localization site (p = 0.05). Median of PCNA index was 42.2 (range 5.9 to 85.2). There was no difference between the p53 overexpression group and the normal group in proliferative activity determined by PCNA (p = 0.73). In univariate analyses, localization site, grade, stage, invasion pattern, lymph node status, were significant factors in estimating disease free survival (DFS). Grade was the most important factor affecting recurrence (p = 0.002). In multivariate analyses, grade was the only significant predictor for DFS (p = 0.001). Grade (p = 0.001) and invasion pattern (p = 0.03) were found to be significant predictors of overall survival. In conclusion, the histological grade was the most reliable important prognostic factor. Further studies are necessary to facilitate understanding of the mechanisms of laryngeal carcinogenesis.  相似文献   
12.
The aim of this study was to investigate the effects of melatonin on low‐grade inflammation and oxidative stress in young male Zucker diabetic fatty (ZDF) rats, an experimental model of metabolic syndrome and type 2 diabetes mellitus (T2DM). ZDF rats (n = 30) and lean littermates (ZL) (n = 30) were used. At 6 wk of age, both lean and fatty animals were subdivided into three groups, each composed of 10 rats: naive (N), vehicle treated (V), and melatonin treated (M) (10 mg/kg/day) for 6 wk. Vehicle and melatonin were added to the drinking water. Pro‐inflammatory state was evaluated by plasma levels of interleukin‐6 (IL‐6), tumor necrosis factor‐α (TNF‐α), and C‐reactive protein (CRP). Also, oxidative stress was assessed by plasma lipid peroxidation (LPO), both basal and after Fe2+/H2O2 inducement. ZDF rats exhibited higher levels of IL‐6 (112.4 ± 1.5 pg/mL), TNF‐α (11.0 ± 0.1 pg/mL) and CRP (828 ± 16.0 µg/mL) compared with lean rats (IL‐6, 89.9 ± 1.0, < 0.01; TNF‐α, 9.7 ± 0.4, < 0.01; CRP, 508 ± 21.5, < 0.001). Melatonin lowered IL‐6 (10%, < 0.05), TNF‐α (10%, < 0.05), and CRP (21%, < 0.01). Basal and Fe2+/H2O2‐induced LPO, expressed as malondialdehyde equivalents (µmol/L), were higher in ZDF rats (basal, 3.2 ± 0.1 versus 2.5 ± 0.1 in ZL, < 0.01; Fe2+/H2O2‐induced, 8.7 ± 0.2 versus 5.5 ± 0.3 in ZL; < 0.001). Melatonin improved basal LPO (15%, < 0.05) in ZDF rats, and Fe2+/H2O2‐ induced LPO in both ZL (15.2%, < 0.01) and ZDF rats (39%, < 0.001). These results demonstrated that oral melatonin administration ameliorates the pro‐inflammatory state and oxidative stress, which underlie the development of insulin resistance and their consequences, metabolic syndrome, diabetes, and cardiovascular disease.  相似文献   
13.
14.
15.
16.
17.

Background

Haematological cancer (HC) patients are increasingly requiring intensive care (ICUs). The aim of this study was to investigate the outcome of HC patients in our ICU and evaluate 5 days-full support as a breakpoint for patients’ re-assessment for support.

Methods

Retrospective study enrolling 112 consecutive HC adults, requiring ICU in January-December 2015. Patients’ data were collected from medical records and Infection Control Committee surveillance reports. Logistic regression analysis was performed to identify independent risk factors for ICU mortality.

Results

Sixty-one were neutropenic, and 99 (88%) had infection at ICU admission. Acute myeloid leukaemia was diagnosed in 43%. Thirty-five (31%) were hematopoietic stem cell transplant recipients. Only 17 (15%) were in remission. Eighty-nine underwent mechanical ventilation on admission. Fifty-three patients acquired ICU-infection (35 bacteremia) being gram negative bacteria (Klebsiella pneumoniae and non-fermenters) the top pathogens. However, ICU-acquired infection had no impact on mortality. The overall ICU and 1-year survival rate was 27% (30 patients) and 7% (8 patients), respectively. Moreover, only 2/62 patients survived with APACHE II score ≥25. The median time for death was 4 days. APACHE II score ≥25 [OR:35.20], septic shock [OR:8.71] and respiratory failure on admission [OR:10.55] were independent risk factors for mortality in multivariate analysis. APACHE II score ≥25 was a strong indicator for poor outcome (ROC under curve 0.889).

Conclusions

APACHE II score ≥25 and septic shock were criteria of ICU futility. Our findings support the full support of patients for 5 days and the need to implement a therapeutic limitations protocol.  相似文献   
18.
19.
20.
Levels of somatostatin were investigated in the ankles and spinal cords of rats suffering from acute and chronic adjuvant arthritis. As measured by radioimmunoassay, somatostatin showed significantly higher concentrations only in chronic arthritic ankles. No significant difference was observed in somatostatin levels between the spinal cords of normal and arthritic groups. Using immunohistochemical labeling and electron microscopy, we observed increased somatostatin labeling in the mature bone matrix, monocytes, and polymorphonuclear cells of bone marrow and macrophage-like synovial cells of chronically arthritic rats. Understanding the mechanism(s) which lead to increased somatostatin in chronic arthritic joints may result in more effective treatment methods.  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