全文获取类型
收费全文 | 2813篇 |
免费 | 660篇 |
国内免费 | 200篇 |
专业分类
3673篇 |
出版年
2024年 | 45篇 |
2023年 | 165篇 |
2022年 | 181篇 |
2021年 | 207篇 |
2020年 | 192篇 |
2019年 | 213篇 |
2018年 | 176篇 |
2017年 | 162篇 |
2016年 | 200篇 |
2015年 | 206篇 |
2014年 | 303篇 |
2013年 | 237篇 |
2012年 | 118篇 |
2011年 | 181篇 |
2010年 | 80篇 |
2009年 | 112篇 |
2008年 | 105篇 |
2007年 | 115篇 |
2006年 | 97篇 |
2005年 | 93篇 |
2004年 | 80篇 |
2003年 | 78篇 |
2002年 | 63篇 |
2001年 | 40篇 |
2000年 | 36篇 |
1999年 | 27篇 |
1998年 | 4篇 |
1997年 | 9篇 |
1996年 | 6篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1993年 | 5篇 |
1992年 | 5篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 4篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1984年 | 12篇 |
1983年 | 8篇 |
1982年 | 15篇 |
1981年 | 9篇 |
1980年 | 6篇 |
1979年 | 11篇 |
1978年 | 8篇 |
1977年 | 7篇 |
1976年 | 4篇 |
1975年 | 5篇 |
1973年 | 3篇 |
1972年 | 3篇 |
排序方式: 共有3673条查询结果,搜索用时 15 毫秒
51.
Jun Wang Shaojun Yu Guofeng Chen Muxing Kang Xiaoli Jin Yi Huang Lele Lin Dan Wu Lie Wang Jian Chen 《Journal of cellular and molecular medicine》2020,24(15):8491-8504
Colorectal cancer (CRC) is one of the most commonly diagnosed cancers with an estimated 1.8 million new cases worldwide and associated with high mortality rates of 881 000 CRC‐related deaths in 2018. Screening programs and new therapies have only marginally improved the survival of CRC patients. Immune‐related genes (IRGs) have attracted attention in recent years as therapeutic targets. The aim of this study was to identify an immune‐related prognostic signature for CRC. To this end, we combined gene expression and clinical data from the CRC data sets of The Cancer Genome Atlas (TCGA) into an integrated immune landscape profile. We identified a total of 476 IRGs that were differentially expressed in CRC vs normal tissues, of which 18 were survival related according to univariate Cox analysis. Stepwise multivariate Cox proportional hazards analysis established an immune‐related prognostic signature consisting of SLC10A2, FGF2, CCL28, NDRG1, ESM1, UCN, UTS2 and TRDC. The predictive ability of this signature for 3‐ and 5‐year overall survival was determined using receiver operating characteristics (ROC), and the respective areas under the curve (AUC) were 79.2% and 76.6%. The signature showed moderate predictive accuracy in the validation and GSE38832 data sets as well. Furthermore, the 8‐IRG signature correlated significantly with tumour stage, invasion, lymph node metastasis and distant metastasis by univariate Cox analysis, and was established an independent prognostic factor by multivariate Cox regression analysis for CRC. Gene set enrichment analysis (GSEA) revealed a relationship between the IRG prognostic signature and various biological pathways. Focal adhesions and ECM‐receptor interactions were positively correlated with the risk scores, while cytosolic DNA sensing and metabolism‐related pathways were negatively correlated. Finally, the bioinformatics results were validated by real‐time RT?qPCR. In conclusion, we identified and validated a novel, immune‐related prognostic signature for patients with CRC, and this signature reflects the dysregulated tumour immune microenvironment and has a potential for better CRC patient management. 相似文献
52.
Bayesian clinical trial designs offer the possibility of a substantially reduced sample size, increased statistical power, and reductions in cost and ethical hazard. However when prior and current information conflict, Bayesian methods can lead to higher than expected type I error, as well as the possibility of a costlier and lengthier trial. This motivates an investigation of the feasibility of hierarchical Bayesian methods for incorporating historical data that are adaptively robust to prior information that reveals itself to be inconsistent with the accumulating experimental data. In this article, we present several models that allow for the commensurability of the information in the historical and current data to determine how much historical information is used. A primary tool is elaborating the traditional power prior approach based upon a measure of commensurability for Gaussian data. We compare the frequentist performance of several methods using simulations, and close with an example of a colon cancer trial that illustrates a linear models extension of our adaptive borrowing approach. Our proposed methods produce more precise estimates of the model parameters, in particular, conferring statistical significance to the observed reduction in tumor size for the experimental regimen as compared to the control regimen. 相似文献
53.
The global impact of the converging dual epidemics of tuberculosis (TB) and human immunodeficiency virus (HIV) is one of the
major public health challenges of our time. The World Health Organization (WHO) reports 9.2 million new cases of TB in 2006
of whom 7.7% were HIV-infected. Tuberculosis is the most common opportunistic infection in HIV-infected patients as well as
the leading cause of death. Further, there has been an increase in rates of drug resistant tuberculosis, including multi-drug
(MDRTB) and extensively drug resistant TB (XDRTB), which are difficult to treat and contribute to increased mortality. The
diagnosis of TB is based on sputum smear microscopy, a 100-year old technique and chest radiography, which has problems of
specificity. Extra-pulmonary, disseminated and sputum smear negative manifestations are more common in patients with advanced
immunosuppression. Newer diagnostic tests are urgently required that are not only sensitive and specific but easy to use in
remote and resource-poor settings. Treatment of HIV-TB co-infection is complex and associated with high pill burden, overlapping
drug toxicities, risk of immune reconstitution inflammatory syndrome (IRIS) and challenges related to adherence. From a programmatic
point of view, screening of all HIV-infected persons for tuberculosis and vice-versa will help identify co-infected patients
who require treatment for both infections. This requires good coordination and communication between the TB and AIDS control
programs, in India. 相似文献
54.
The N-terminal fragment of pro B-type natriuretic peptide (NT-proBNP) and proBNP are used as gold standard clinical markers of myocardial dysfunction such as cardiac hypertrophy and left ventricle heart failure. The actual circulating molecular forms of these peptides have been the subject of intense investigation particularly since these analytes are measured in clinical assays. Conflicting data has been reported and no firm consensus on the exact nature of the molecular species exists. Because these clinical assays are immunoassay-based, specific epitopes are detected. It is conceivable then that certain epitopes may be masked and therefore unavailable for antibody binding, thus the importance of determining the nature of the circulating molecular forms of these analytes. This situation is an unavoidable Achilles’ heel of immunoassays in general.A recombinant O-linked glycosylated form of proBNP has been show to mimic some of the properties of extracted plasma from a heart failure patient. In particular the recombinant and native material co-migrated as diffuse Western-immunostained bands on SDS-PAGE and each band collapsed to an apparent homogeneous band following deglycosylation. Thus, glycosylated-proBNP may be one such circulating form. Here we provide extensive physiochemical characterization for this O-linked protein and compare these results to other described circulating species, non-glycosylated-proBNP and NT-proBNP. It will be shown that glycosylation has no influence on the secondary and quaternary structure of proBNP. In fact, at moderate concentration in benign physiological neutral pH buffer, all three likely circulating species are essentially devoid of major secondary structure, i.e., are intrinsically unstructured proteins (IUPs). Furthermore, all three proteins exist as monomers in solution. These results may have important implications in the design of NT-proBNP/BNP immunoassays. 相似文献
55.
56.
57.
58.
总结疏血通注射液的临床应用,从文献报道来看,疏血通注射液目前广泛用于治疗脑、心、肾及周围血管血栓性病变、糖尿病、糖尿病肾病等,疗效显著、安全性高、不良反应少而轻微,具有广泛的应用前景。 相似文献
59.
60.