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   5500篇
  免费   401篇
  国内免费   44篇
耳鼻咽喉   68篇
儿科学   122篇
妇产科学   214篇
基础医学   687篇
口腔科学   159篇
临床医学   614篇
内科学   1320篇
皮肤病学   86篇
神经病学   329篇
特种医学   348篇
外科学   705篇
综合类   129篇
预防医学   198篇
眼科学   158篇
药学   372篇
中国医学   39篇
肿瘤学   397篇
  2023年   20篇
  2022年   48篇
  2021年   118篇
  2020年   73篇
  2019年   90篇
  2018年   148篇
  2017年   111篇
  2016年   132篇
  2015年   245篇
  2014年   220篇
  2013年   242篇
  2012年   400篇
  2011年   381篇
  2010年   234篇
  2009年   171篇
  2008年   291篇
  2007年   298篇
  2006年   274篇
  2005年   254篇
  2004年   245篇
  2003年   295篇
  2002年   259篇
  2001年   192篇
  2000年   167篇
  1999年   126篇
  1998年   56篇
  1997年   38篇
  1996年   39篇
  1995年   29篇
  1994年   26篇
  1993年   34篇
  1992年   93篇
  1991年   70篇
  1990年   63篇
  1989年   57篇
  1988年   55篇
  1987年   58篇
  1986年   49篇
  1985年   28篇
  1984年   19篇
  1983年   19篇
  1982年   15篇
  1981年   14篇
  1980年   9篇
  1979年   25篇
  1978年   14篇
  1977年   15篇
  1974年   9篇
  1973年   9篇
  1972年   10篇
排序方式: 共有5945条查询结果,搜索用时 15 毫秒
991.

Background

Stroke severity is an important outcome predictor for intracerebral hemorrhage (ICH) but is typically unavailable in administrative claims data. We validated a claims-based stroke severity index (SSI) in patients with ICH in Taiwan.

Methods

Consecutive ICH patients from hospital-based stroke registries were linked with a nationwide claims database. Stroke severity, assessed using the National Institutes of Health Stroke Scale (NIHSS), and functional outcomes, assessed using the modified Rankin Scale (mRS), were obtained from the registries. The SSI was calculated based on billing codes in each patient's claims. We assessed two types of criterion-related validity (concurrent validity and predictive validity) by correlating the SSI with the NIHSS and the mRS. Logistic regression models with or without stroke severity as a continuous covariate were fitted to predict mortality at 3, 6, and 12 months.

Results

The concurrent validity of the SSI was established by its significant correlation with the admission NIHSS (r = 0.731; 95% confidence interval [CI], 0.705–0.755), and the predictive validity was verified by its significant correlations with the 3-month (r = 0.696; 95% CI, 0.665–0.724), 6-month (r = 0.685; 95% CI, 0.653–0.715) and 1-year (r = 0.664; 95% CI, 0.622–0.702) mRS. Mortality models with NIHSS had the highest area under the receiver operating characteristic curve, followed by models with SSI and models without any marker of stroke severity.

Conclusions

The SSI appears to be a valid proxy for the NIHSS and an effective adjustment for stroke severity in studies of ICH outcome with administrative claims data.  相似文献   
992.
993.
994.

Background:

We aimed to identify prognostic blood biomarkers using proteomics-based approaches in malignant pleural mesothelioma (MPM).

Methods:

Plasma samples from 12 MPM patients were used for exploratory mass spectrometry and ELISA analyses. The significance of secreted protein acidic and rich in cysteine (SPARC) was examined in sera from a Dutch series (n=97). To determine the source of the circulating SPARC, we investigated SPARC expression in MPM tumours and healthy controls, as well as the expression and secretion from cell lines and xenografts.

Results:

Secreted protein acidic and rich in cysteine was identified as a putative prognostic marker in plasma. Validation in the Dutch series showed that the median survival was higher in patients with low SPARC compared with those with high SPARC (19.0 vs 8.8 months; P=0.01). In multivariate analyses, serum SPARC remained as an independent predictor (HR 1.55; P=0.05). In MPM tumour samples, SPARC was present in the tumour cells and stromal fibroblasts. Cellular SPARC expression was higher in 5 out of 7 cell lines compared with two immortalized mesothelial lines. Neither cell lines nor xenograft tumours secreted detectable SPARC.

Conclusions:

Low circulating SPARC was associated with favourable prognosis. Secreted protein acidic and rich in cysteine was present in both tumour cells and stromal fibroblasts; and our in vitro and in vivo experiments suggest that stromal fibroblasts are a potential source of circulating SPARC.  相似文献   
995.
996.
997.
998.
A 48-year-old woman suddenly lost consciousness as a result of a right rostral pontine tegmentum haemorrhage. The patient presented with decerebrate rigidity (DR) and regained full consciousness 5 days after the initial onset. The patient was given gabapentin 1200 mg/day nasogastrically and her DR significantly improved, although other antiepileptic drugs such as phenytoin and carbamazepine were given in larger dosages to decrease muscle hypertonicity. The patients' preserved consciousness and motor-evoked potentials to transcranial magnetic stimulation indicated a derangement of the extrapyramidal tracts with preservation of the pyramidal tracts. This case report discusses the possible mechanisms of action of gabapentin in DR.  相似文献   
999.
Propofol (PPF), a widely used intravenous anesthetic for induction and maintenance of anesthesia during surgeries, was found to possess suppressive effect on host immunity. This study aimed at investigating whether PPF plays a modulatory role in the lipopolysaccharide (LPS)-induced inflammatory cytokine expression in a cell line of rat hepatocytes. Morphological observation and viability assay showed that PPF exhibits no cytotoxicity at concentrations up to 300 microM after 48 h incubation. Pretreatment with 100 microM PPF for 24 h prior to LPS stimulation was performed to investigate the modulatory effect on LPS-induced inflammatory gene production. The results of semi-quantitative RT-PCR demonstrated that PPF pretreatment significantly suppressed the LPS-induced toll-like receptor (TLR)-4, CD14, tumor necrosis factor (TNF)-alpha, and granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression. Western blotting analysis showed that PPF pretreatment potentiated the LPS-induced TLR-4 downregulation. Flow cytometrical analysis revealed that PPF pretreatment showed no modulatory effect on the LPS-upregulated CD14 expression on hepatocytes. In addition, PPF pretreatment attenuated the phosphorylation of mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) and IkappaBalpha, as well as the nuclear translocation of NF-kappaB primed by LPS. Moreover, addition of PD98059, a MAPK kinase inhibitor, significantly suppressed the LPS-induced NF-kappaB nuclear translocation and GM-CSF production, suggesting that the PPF-attenuated GM-CSF production in hepatocytes may be attributed to its suppressive effect on MAPK/ERK signaling pathway. In conclusion, PPF as an anesthetic may clinically benefit those patients who are vulnerable to sepsis by alleviating sepsis-related inflammatory response in livers.  相似文献   
1000.
This study evaluated the effect of global budgeting on health service utilization, health care expenditures, and the quality of care among patients with pneumonia in Taiwan. The National Health Insurance Research Database (NHIRD) was used for analysis. Data on patients diagnosed with pneumonia during 2000–2001 (the prebudget group) were used as the baseline data, and data on patients diagnosed with pneumonia during 2004–2005 (the postbudget group) were used as the postintervention data. The length of stay (LOS), diagnostic costs, drug costs, therapy costs, total costs, risk of readmission within 14 days, and risk of revisiting the Emergency Department (ED) within 3 days of discharge before and after implementing the global budget system were analyzed and compared. Data on 32,535 patients with pneumonia were analyzed. The mean LOS increased from 6.36?±?0.07 to 10.78?±?0.09 days after implementing the global budget system. The mean total costs in the prebudget and postbudget groups were 22,697.82?±?542.40 and 62,016.7?±?793.19 New Taiwan dollars (NT$), respectively. The mean rate of revisiting the ED within 3 days decreased from 5.5?±?0.2 % to 4.6?±?0.1 % in the prebudget and postbudget groups, respectively. The mean rates of readmission within 14 days before were 6.1?±?0.2 % and 8.2?±?0.2 % in the prebudget and postbudget groups, respectively. Global budgeting is associated with a significantly longer LOS, higher health care costs, and poorer quality of care among patients with pneumonia.  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