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   3294篇
  免费   174篇
  国内免费   17篇
耳鼻咽喉   131篇
儿科学   46篇
妇产科学   20篇
基础医学   421篇
口腔科学   31篇
临床医学   271篇
内科学   826篇
皮肤病学   32篇
神经病学   128篇
特种医学   94篇
外科学   724篇
综合类   10篇
预防医学   157篇
眼科学   79篇
药学   293篇
中国医学   24篇
肿瘤学   198篇
  2023年   21篇
  2022年   47篇
  2021年   88篇
  2020年   39篇
  2019年   81篇
  2018年   95篇
  2017年   56篇
  2016年   70篇
  2015年   123篇
  2014年   146篇
  2013年   139篇
  2012年   282篇
  2011年   235篇
  2010年   134篇
  2009年   128篇
  2008年   217篇
  2007年   231篇
  2006年   196篇
  2005年   190篇
  2004年   166篇
  2003年   123篇
  2002年   97篇
  2001年   95篇
  2000年   73篇
  1999年   70篇
  1998年   22篇
  1997年   17篇
  1996年   18篇
  1995年   11篇
  1994年   21篇
  1993年   6篇
  1992年   24篇
  1991年   30篇
  1990年   29篇
  1989年   17篇
  1988年   15篇
  1987年   23篇
  1986年   10篇
  1985年   8篇
  1984年   6篇
  1983年   8篇
  1982年   6篇
  1980年   6篇
  1979年   10篇
  1978年   8篇
  1977年   8篇
  1976年   7篇
  1975年   6篇
  1974年   4篇
  1973年   4篇
排序方式: 共有3485条查询结果,搜索用时 15 毫秒
71.

Background and objectives

Remission in the majority of ANCA vasculitis patients is not sustained after a single course of rituximab, and risk of relapse warrants development of a successful strategy to ensure durable remission.

Design, setting, participants, & measurements

A retrospective analysis of ANCA vasculitis patients who underwent maintenance therapy using rituximab-induced continuous B-cell depletion for up to 7 years was performed. Maintenance therapy with rituximab was initiated after achieving remission or converting from other prior maintenance therapy. Continuous B-cell depletion was achieved in all patients by scheduled rituximab administration every 4 months. Disease activity, serologic parameters, adverse events, and survival were examined.

Results

In the study, 172 patients (mean age=60 years, 55% women, 57% myeloperoxidase–ANCA) treated from April of 2006 to March of 2013 underwent continuous B-cell depletion with rituximab. Median remission maintenance follow-up time was 2.1 years. Complete remission (Birmingham Vasculitis Activity Score [BVAS]=0) was achieved in all patients. Major relapse (BVAS≥3) occurred in 5% of patients and was associated with weaning of other immunosuppression drugs. Remission was reinduced in all patients. Survival mirrored survival of a general age-, sex-, and ethnicity-matched United States population.

Conclusion

This analysis provides evidence for long-term disease control using continuous B-cell depletion. This treatment strategy in ANCA vasculitis patients also seems to result in survival rates comparable with rates in a matched reference population. These findings suggest that prospective remission maintenance treatment trials using continuous B-cell depletion are warranted.  相似文献   
72.

Purpose

In clinical practice, some patients with asthma show incompletely reversible airflow obstruction, resembling chronic obstructive pulmonary disease (COPD). The aim of this study was to analyze this overlap phenotype of asthma with COPD feature.

Materials and Methods

A total of 256 patients, over the age of 40 years or more with a diagnosis of asthma, based on either 1) positive response to bronchodilator: >200 mL forced expiratory volume in 1 s (FEV1) and >12% baseline or 2) positive methacholine or mannitol provocation test, were enrolled. Among the asthma patients, we defined the overlap group with incompletely reversible airflow obstruction [postbronchodilator FEV1/forced vital capacity (FVC) <70] at the initial time of admission and continuing airflow obstruction after at least 3 months follow up. We evaluated clinical features, serum eosinophil counts, serum total immunoglobulin (Ig) E with allergy skin prick test, spirometry, methacholine or mannitol provocation challenges and bronchodilator responses, based on their retrospective medical record data. All of the tests mentioned above were performed within one week.

Results

The study population was divided into two groups: asthma only (62%, n=159, postbronchodilator FEV1/FVC ≥70) and overlap group (38%, n=97, postbronchodilator FEV1/FVC <70). The overlap group was older, and contained more males and a higher percentage of current or ex-smokers than the asthma only group. Significantly lower FEV1 and higher total lung capacity, functional residual capacity, and residual volume were observed in the overlap group. Finally, significantly lower serum eosinophil count and higher IgE were seen in the overlap group.

Conclusion

Our results showed that the overlap phenotype was older, male asthmatic patients who have a higher lifetime smoking intensity, more atopy and generally worse lung function.  相似文献   
73.
Falls are a major health problem for elderly populations worldwide. We analyzed data from the 2011 Korean Community Health Survey to identify potential risk factors for falls in a representative population-based sample of community-dwelling older Korean adults. Risk factors for falls were assessed by multivariate survey logistic regression models. The prevalence of falls was 36.5% in males and 63.5% in females. Age and female sex were associated with a higher risk of falls. Similarly, living alone, living in an urban area, poor self-rated health, and high stress were associated with a high risk of falls. Subjects with diabetes mellitus, stroke, osteoarthritis, osteoporosis, urinary incontinence, cataracts, or depression had a high risk of falls. However, subjects with hypertension were at low risk for falls. In conclusion, age, female sex, marital status, residence location, self-rated health, stress, and several chronic conditions were significantly associated with the risk for falls in the older Korean adults. Our findings suggest that these risk factors should be addressed in public health policies for preventing falls.

Graphical Abstract

  相似文献   
74.
The purpose of this study was to compare the Korean COPD guideline to GOLD consensus report in terms of acute exacerbation. A total of 361 patients were enrolled in this study, and 16.9% of them experienced acute exacerbation during the follow-up. A total of 6.3% of patients in GOLD A, 9.5% in GOLD B, 7.7% in GOLD C and 17.0% of GOLD D experienced exacerbation during the first year of follow-up, respectively (P=0.09). There was no one who experienced exacerbation during the first year of follow-up in the Korean group ''ga''. The 12-month exacerbation rates of Korean group ''na'' and ''da'' were 4.5% and 16.0%, respectively (P<0.001). We explore the experience of exacerbation in patients with change of their risk group after applying Korean COPD guideline. A total of 16.0% of the patients who were reclassified from GOLD A to Korean group ''da'' experienced acute exacerbation,and 15.3% from GOLD B to Korean group ''da'' experienced acute exacerbation. In summary, the Korean COPD guideline is useful to differentiate the high risk from low risk for exacerbation in terms of spirometry. This indicates that application of Korean COPD guideline is appropriate to treat Korean COPD patients.  相似文献   
75.
2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) is a well‐known environmental contaminant that produces a wide variety of adverse effects in humans. Catalpol, a major bioactive compound enriched in the dried root of Rehmannia glutinosa, is a major iridoid glycoside that alleviates bone loss. However, the detailed mechanisms underlying the effects of catalpol remain unclear. The present study evaluated the effects of catalpol on TCDD‐induced cytotoxicity in osteoblastic MC3T3‐E1 cells. Catalpol inhibited TCDD‐induced reduction in cell viability and increases in apoptosis and autophagic activity in osteoblastic MC3T3‐E1 cells. Additionally, pretreatment with catalpol significantly decreased the nitric oxide and nitrite levels compared with a control in TCDD‐treated cells and significantly inhibited TCDD‐induced increases in the levels of cytochrome P450 1A1 and extracellular signal‐regulated kinase. Pretreatment with catalpol also effectively restored the expression of superoxide dismutase and extracellular signal‐regulated kinase 1 and significantly enhanced the expression of glutathione peroxidase 4 and osteoblast differentiation markers, including alkaline phosphatase and osterix. Taken together, these findings demonstrate that catalpol has preventive effects against TCDD‐induced damage in MC3T3‐E1 osteoblastic cells.  相似文献   
76.
77.
78.
79.
80.
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