全文获取类型
收费全文 | 10193708篇 |
免费 | 653029篇 |
国内免费 | 165854篇 |
专业分类
耳鼻咽喉 | 131754篇 |
儿科学 | 283648篇 |
妇产科学 | 232185篇 |
基础医学 | 1257828篇 |
口腔科学 | 265265篇 |
临床医学 | 1032899篇 |
内科学 | 1703284篇 |
皮肤病学 | 204495篇 |
神经病学 | 731573篇 |
特种医学 | 379216篇 |
外国民族医学 | 1694篇 |
外科学 | 1335669篇 |
综合类 | 736370篇 |
现状与发展 | 520篇 |
一般理论 | 3726篇 |
预防医学 | 826138篇 |
眼科学 | 231384篇 |
药学 | 881330篇 |
3413篇 | |
中国医学 | 223924篇 |
肿瘤学 | 546276篇 |
出版年
2023年 | 53983篇 |
2022年 | 132301篇 |
2021年 | 201956篇 |
2020年 | 145319篇 |
2019年 | 147382篇 |
2018年 | 179825篇 |
2017年 | 160630篇 |
2016年 | 157264篇 |
2015年 | 203894篇 |
2014年 | 286547篇 |
2013年 | 376568篇 |
2012年 | 528894篇 |
2011年 | 573916篇 |
2010年 | 391132篇 |
2009年 | 351130篇 |
2008年 | 488735篇 |
2007年 | 508456篇 |
2006年 | 485347篇 |
2005年 | 446665篇 |
2004年 | 391385篇 |
2003年 | 362617篇 |
2002年 | 333976篇 |
2001年 | 314119篇 |
2000年 | 312056篇 |
1999年 | 266857篇 |
1998年 | 111537篇 |
1997年 | 98065篇 |
1996年 | 92002篇 |
1995年 | 84058篇 |
1994年 | 76142篇 |
1993年 | 65258篇 |
1992年 | 183155篇 |
1991年 | 177139篇 |
1990年 | 171769篇 |
1989年 | 166680篇 |
1988年 | 154140篇 |
1987年 | 150200篇 |
1986年 | 142961篇 |
1985年 | 136192篇 |
1984年 | 103713篇 |
1983年 | 89039篇 |
1982年 | 56706篇 |
1979年 | 93078篇 |
1978年 | 66788篇 |
1977年 | 57599篇 |
1975年 | 58439篇 |
1974年 | 67410篇 |
1973年 | 64330篇 |
1972年 | 59449篇 |
1971年 | 55070篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
971.
Xiujuan Tian Zhiying Chen Shaomin Shi Xianwen Wang Wanli Wang Ning Li Jing Wang 《Medicine》2015,94(37)
Oral cancer, predominantly oral squamous cell carcinoma (OSCC), is one of the most leading causes of cancers worldwide. Due to a low 5-year survival rate, highly effective methods for the early detection of OSCC are totally needed. MicroRNAs (miRNAs), as promising biomarkers, can bring insights into tumorigenesis of oral cancers. However, studies on the accuracy of miRNAs detection in OSCC have inconsistent conclusions, leading us to conduct this meta-analysis. The aim of this study was to systematically review the articles investigating the diagnostic value of miRNAs in OSCC.The PubMed, Embase, Chinese National Knowledge Infrastructure (CNKI), Web of Science were searched (updated to June 11th, 2015) to identify all articles evaluating the diagnostic yield of miRNAs for OSCC. The pooled sensitivity, specificity, and other diagnostic parameters were used to assess the performance of miRNAs assays on OSCC detection. Statistical analysis was conducted by employing the R software.The present meta-analysis comprised 23 studies from 10 articles, including 598 OSCC patients and 320 healthy individuals, available for analysis. The summary receiver operator characteristic (SROC) curve was plotted. Meanwhile, the pooled diagnostic parameters and the area under curve (AUC) were calculated based on all included studies. The pooled diagnostic parameters calculated from all 23 studies were as follows: pooled sensitivity of 0.759 (95% CI: 0.701–0.809), pooled specificity of 0.773 (95% CI: 0.713–0.823) and AUC of 0.832, which indicates a relatively high diagnostic accuracy of miRNAs in differentiating OSCC patients from healthy controls. Meanwhile, In addition, subgroup analyses were conducted to access the heterogeneity between studies, which is based on specimen (serum/plasma/blood/saliva/ tissue) and ethnicity (Asian/Caucasian).In summary, our meta-analysis suggests that miRNAs might be used in noninvasive screening tests for OSCC, which needs further large-scale studies to be validated. 相似文献
972.
Feasibility and Diagnostic Potential of Pulmonary Transit Time Measurement by Contrast Echocardiography: A Pilot Study
下载免费PDF全文
![点击此处可从《Echocardiography (Mount Kisco, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
973.
974.
Harit Kapoor Kush Raj Lohani Tommy H. Lee Devendra K. Agrawal Sumeet K. Mittal 《CTS Clinical and Translational Science》2015,8(6):841-847
Esophageal adenocarcinoma is the fastest rising cancer in the United States. It develops from long‐standing gastroesophageal reflux disease which affects >20% of the general population. It carries a very poor prognosis with 5‐year survival <20%. The disease is known to sequentially progress from reflux esophagitis to a metaplastic precursor, Barrett''s esophagus and then onto dysplasia and esophageal adenocarcinoma. However, only few patients with reflux develop Barrett''s esophagus and only a minority of these turn malignant. The reason for this heterogeneity in clinical progression is unknown. To improve patient management, molecular changes which facilitate disease progression must be identified. Animal models can provide a comprehensive functional and anatomic platform for such a study. Rats and mice have been the most widely studied but disease homology with humans has been questioned. No animal model naturally simulates the inflammation to adenocarcinoma progression as in humans, with all models requiring surgical bypass or destruction of existing antireflux mechanisms. Valuable properties of individual models could be utilized to holistically evaluate disease progression. In this review paper, we critically examined the current animal models of Barrett''s esophagus, their differences and homologies with human disease and how they have shaped our current understanding of Barrett''s carcinogenesis. 相似文献
975.
976.
Arthroscopic acromioclavicular joint excision is a commonly performed but technically demanding procedure. Incomplete excision can leave residual symptoms. We present a simple, reproducible technique ensuring satisfactory excision of the joint. 相似文献
977.
Marta Rozanski Valentin Neuhaus Emily Thornton Stéphanie J. E. Becker James P. Rathmell David Ring 《Journal of hand and microsurgery》2015,7(1):30-35
This study used the National Survey of Ambulatory Surgery (NSAS) database to measure the incidence of and risk factors for symptoms in the ambulatory surgery center and problems within 24 h after isolated carpal tunnel release (CTR). The NSAS contained records on 400,000 adult patients with carpal tunnel syndrome who were treated with CTR in 2006, based on ICD-9 codes. The type of anesthesia used and factors associated with symptoms and problems were sought in bivariate and multivariable statistical analyses. The mean duration of the procedure was 16 ± 8.8 min. Only 5 % were performed under local anesthesia without sedation, 45 % with IV sedation, 28 % regional anesthesia, and 19 % general anesthesia. Symptoms in the ambulatory surgery center or a problem within 24 h after discharge were recorded in 10 % of patients, all of them minor and transient, including difficulties with pain and its treatment. The strongest risk factors were male sex, age of 45 years and older, and participation of an anesthesiologist. Local anesthesia and regional anesthesia were associated with more perioperative symptoms and postoperative problems. Most CTR are performed with some sedation in the United States. CTR is a safe procedure: one in 10 patients will experience a minor issue in the perioperative or immediate postoperative period. 相似文献
978.
Gautam Chakrabarty Mayank Vashishtha Daniel Leeder 《Journal of Clinical Orthopaedics and Trauma》2015,6(2):108-112
Polyethylene (PE) has been used extensively in knee arthroplasty since the mid 20th century. Progress in material manufacturing and processing has led to newer polyethylenes over last few decades with different material properties. It has been established that PE wear in knee arthroplasty causes particle induced osteolysis which is the main reason for late failure and requires revision surgery. Although there are various causes of wear, the properties of PE have long been a matter of investigation as a contributory factor. The advent of newer highly cross linked PE has been shown to improve wear rates in hip arthroplasty but the benefits have not been shown to be of the same degree in knee arthroplasty. The laboratory and clinical studies so far are limited and slightly conflicting in their conclusions. The risks of using highly cross linked PE in knee arthroplasty include tibial post fracture, disruption of locking mechanism, liner fracture which can lead to increased wear and osteolysis. The current evidence suggests that highly cross linked polyethylenes should be used with caution and only considered in younger active patients. The results of a recently completed randomized trial to compare the conventional with high molecular weight PE in knee arthroplasty are awaited. 相似文献
979.
E. M. Peterman C. Sullivan M. F. Goody I. Rodriguez-Nunez J. A. Yoder C. H. Kim 《Infection and immunity》2015,83(1):430-440
Mitochondria are known primarily as the location of the electron transport chain and energy production in cells. More recently, mitochondria have been shown to be signaling centers for apoptosis and inflammation. Reactive oxygen species (ROS) generated as by-products of the electron transport chain within mitochondria significantly impact cellular signaling pathways. Because of the toxic nature of ROS, mitochondria possess an antioxidant enzyme, superoxide dismutase 2 (SOD2), to neutralize ROS. If mitochondrial antioxidant enzymes are overwhelmed during severe infections, mitochondrial dysfunction can occur and lead to multiorgan failure or death. Pseudomonas aeruginosa is an opportunistic pathogen that can infect immunocompromised patients. Infochemicals and exotoxins associated with P. aeruginosa are capable of causing mitochondrial dysfunction. In this work, we describe the roles of SOD2 and mitochondrial ROS regulation in the zebrafish innate immune response to P. aeruginosa infection. sod2 is upregulated in mammalian macrophages and neutrophils in response to lipopolysaccharide in vitro, and sod2 knockdown in zebrafish results in an increased bacterial burden. Further investigation revealed that phagocyte numbers are compromised in Sod2-deficient zebrafish. Addition of the mitochondrion-targeted ROS-scavenging chemical MitoTEMPO rescues neutrophil numbers and reduces the bacterial burden in Sod2-deficient zebrafish. Our work highlights the importance of mitochondrial ROS regulation by SOD2 in the context of innate immunity and supports the use of mitochondrion-targeted ROS scavengers as potential adjuvant therapies during severe infections. 相似文献
980.