全文获取类型
收费全文 | 20183篇 |
免费 | 1508篇 |
国内免费 | 1217篇 |
出版年
2024年 | 31篇 |
2023年 | 230篇 |
2022年 | 465篇 |
2021年 | 933篇 |
2020年 | 581篇 |
2019年 | 826篇 |
2018年 | 825篇 |
2017年 | 599篇 |
2016年 | 876篇 |
2015年 | 1176篇 |
2014年 | 1431篇 |
2013年 | 1528篇 |
2012年 | 1794篇 |
2011年 | 1628篇 |
2010年 | 1039篇 |
2009年 | 1014篇 |
2008年 | 1140篇 |
2007年 | 1070篇 |
2006年 | 890篇 |
2005年 | 763篇 |
2004年 | 608篇 |
2003年 | 568篇 |
2002年 | 500篇 |
2001年 | 356篇 |
2000年 | 316篇 |
1999年 | 305篇 |
1998年 | 179篇 |
1997年 | 165篇 |
1996年 | 162篇 |
1995年 | 125篇 |
1994年 | 89篇 |
1993年 | 75篇 |
1992年 | 112篇 |
1991年 | 86篇 |
1990年 | 69篇 |
1989年 | 53篇 |
1988年 | 43篇 |
1987年 | 43篇 |
1986年 | 39篇 |
1985年 | 51篇 |
1984年 | 9篇 |
1983年 | 17篇 |
1982年 | 10篇 |
1981年 | 12篇 |
1980年 | 9篇 |
1979年 | 8篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1974年 | 5篇 |
1969年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
961.
Shouyang Song Zhen Yu Yajing You Chenxi Liu Xiaoyu Xie Huanran Lv Feng Xiao Qiang Zhu Chengyong Qin 《Cell death & disease》2022,13(4)
The receptor tyrosine kinases (RTKs) family is well-recognized as vital targets for the treatment of hepatocarcinoma cancer (HCC) clinically, whereas the survival benefit of target therapy sorafenib is not satisfactory for liver cancer patients due to metastasis. EGFR and MET are two molecules of the RTK family that were related to the survival time of liver cancer patients and resistance to targeted therapy in clinical reports. However, the mechanism and clinical therapeutic value of EGFR/MET in HCC metastasis are still not completely clarified. The study confirmed that EGFR/MET was highly expressed in HCC cells and tissues and the phosphorylation was stable after metastasis. The expression of EGFR/MET was up-regulated in circulating tumor microemboli (CTM) to accelerate IL-8 production and resistance to the lethal effect of leukocytes. Meanwhile, highly expressed EGFR/MET effectively regulated the Ras/MAPK pathway and stabilized suspended HCC cells by facilitating proliferation and inhibiting apoptosis. Moreover, EGFR/MET promoted phosphorylation of hetero-RTKs, which was dependent on high-energy phosphoric acid compounds rather than their direct interactions. In conclusion, highly expressed EGFR/MET could be used in CTM identification and suitable for preventing metastasis of HCC in clinical practice.Subject terms: Liver cancer, Metastasis 相似文献
962.
963.
本研究旨在利用生物信息学方法构建经铜诱导的ATP7B基因敲除HepG2细胞系的转录调控网络。探讨关键转录因子在肝豆状核变性发生、发展中的潜在作用机制。收集公共基因表达数据库(gene expression omnibus, GEO)中包含野生型、ATP7B基因敲除型、铜诱导的野生型和铜诱导的ATP7B基因敲除型HepG2细胞系数据。筛选由铜诱导产生的差异表达基因(differentially expressed genes,DEGs)后进行基因本体论(gene ontology,GO)、京都基因和基因组百科全书(Kyoto encyclopedia of genes and genomes, KEGG)富集分析。基于蛋白相互作用网络,识别疾病关键基因和功能模块,并对关键功能模块中的基因进行富集分析。最后,构建转录调控网络,筛选核心转录因子。共筛选出1 034个差异表达基因,其中上调525个,下调509个。上、下调关键功能模块分别包括了3785个和3931个基因。关键功能模块中的基因主要定位于细胞-基质连接、染色体、剪接复合体、核糖体等区域,共同参与了mRNA加工、组蛋白修饰、RNA剪切... 相似文献
964.
965.
966.
Nathaniel Diamant Erik Reinertsen Steven Song Aaron D. Aguirre Collin M. Stultz Puneet Batra 《PLoS computational biology》2022,18(2)
Supervised machine learning applications in health care are often limited due to a scarcity of labeled training data. To mitigate the effect of small sample size, we introduce a pre-training approach, Patient Contrastive Learning of Representations (PCLR), which creates latent representations of electrocardiograms (ECGs) from a large number of unlabeled examples using contrastive learning. The resulting representations are expressive, performant, and practical across a wide spectrum of clinical tasks. We develop PCLR using a large health care system with over 3.2 million 12-lead ECGs and demonstrate that training linear models on PCLR representations achieves a 51% performance increase, on average, over six training set sizes and four tasks (sex classification, age regression, and the detection of left ventricular hypertrophy and atrial fibrillation), relative to training neural network models from scratch. We also compared PCLR to three other ECG pre-training approaches (supervised pre-training, unsupervised pre-training with an autoencoder, and pre-training using a contrastive multi ECG-segment approach), and show significant performance benefits in three out of four tasks. We found an average performance benefit of 47% over the other models and an average of a 9% performance benefit compared to best model for each task. We release PCLR to enable others to extract ECG representations at https://github.com/broadinstitute/ml4h/tree/master/model_zoo/PCLR. 相似文献
967.
968.
目的分析暗色真菌威尼克何德霉菌浅部皮肤及附属器感染的特征。方法收集2016年5月至2020年5月期间我科就诊的威尼克何德霉感染病例7例。总结威尼克何德霉菌的特点,分析皮肤及附属器感染病例的临床特征及诊断。结果其中4例为掌黑癣病例,临床表现均为手部单个扁平、暗棕色斑片,无明显鳞屑,界限清楚。另外3例与掌黑癣的临床表现不同,分别表现为手部湿疹样改变、指甲损害及足癣样变。结论威尼克何德霉除了可引起掌黑癣外,还可能引起手部湿疹样改变、甲真菌病及足癣样变等非掌黑癣表现,掌黑癣可通过临床表现及真菌学检查诊断。若以非掌黑癣为临床表现的威尼克何德霉感染,容易误诊漏诊,应引起临床重视。 相似文献
969.
970.
Yunwei Lou Xueqin Tian Chen Sun Miaomiao Song Meijuan Han Yuxin Zhao Yaru Song Xiangfeng Song Wen Zhang Youhai H. Chen Hui Wang 《Cell death & disease》2022,13(4)
Tumor necrosis factor-α-induced protein 8 (TNFAIP8 or TIPE) is a member of the TNFAIP8 family. While TIPE was broadly considered to be pro-cancerous, its precise roles in carcinogenesis especially those of the intestinal tract are not clear. Here, we show that genetic deletion of TIPE in mice exacerbated chemical-induced colitis and colitis-associated colon cancer. Loss of TIPE exacerbated inflammatory responses and inflammation-associated dysbiosis, leading to the activation of NF-κB and STAT3, and it also accelerated dysplasia, DNA damage and proliferation of intestinal epithelial cells. We further show that colon microbiota were essential for increased tumor growth and progression in Tipe−/− mice. The tumor suppressive function of TIPE originated primarily from the non-hematopoietic compartment. Importantly, TIPE was downregulated in human colorectal cancers, and patients with low levels of Tipe mRNA were associated with reduced survival. These results indicate that TIPE serves as an important modulator of colitis and colitis-associated colon cancer.Subject terms: Cancer microenvironment, Chronic inflammation 相似文献