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The quality of MRI will affect doctor's judgment on patient's physical conditions,and the high-resolution MRI is more conducive to doctor to make an accurate diagnosis.Using computer technology to perform super-resolution reconstruction of MRI can obtain high-resolution MRI from existing low-resolution MRI.Based on the strong generation ability of the generative adversarial networks and the unsupervised learning characteristics of the generative adversarial networks,this paper studies the MRI super-resolution algorithm based on the generative adversarial networks.It designs a generative adversarial network model DNGAN that combines ResNet structure and DenseNet structure.In this network,the WGAN-GP theory is used as the adversarial loss to stabilize the training of the generative adversarial networks.In addition,the content loss function and the perceptual loss function are also used as the loss function of the network.At the same time,in order to make better use of the rich frequency domain information of MRI,the frequency domain information of MRI is added to the network as a frequency domain loss function.In order to prove the effectiveness of DNGAN,the MRI super-resolution experimental results of DNGAN are compared with that of SRGAN and bicubic interpolation method.Experimental results show that DNGAN model can effectively perform super-resolution reconstruction of MRI.

Lung cancer is the most common cause of cancer-related mortality worldwide. It is necessary to improve the understanding of the molecular mechanisms involved in lung cancer in order to develop more effective therapeutics for the treatment of this fatal disease. The canonical Wnt signaling pathway has been known to be important in a number of cancer types, including lung cancer. Pygopus (Pygo) is a recently identified downstream component of the Wnt signaling pathway required for β-catenin/T-cell factor (TCF)-dependent transcription. However, the role of Pygo in lung cancer remains to be elucidated. The present study showed that Pygo2 is overexpressed in human lung cancer tissue samples and cell lines. Expression levels of Pygo2 were found to correlate with cytosolic β-catenin protein levels in the samples examined. Co-immunofluorescent staining showed that Pygo2 protein accumulated in the nuclei and colocalized with nuclear β-catenin in lung cancer cell lines expressing Pygo2. To investigate the functional importance of the Pygo2 overexpression in lung cancer, short hairpin RNA (shRNA) was used to knockdown Pygo2 mRNA in lung cancer cells expressing the gene. Pygo2 shRNA was observed to inhibit cell proliferation and decrease β-catenin/TCF-dependent transcriptional activity in vitro . Furthermore, Pygo2 shRNA significantly suppressed lung cancer xenograft models in vivo (P<0.05). These results suggested that Pygo2 is a putative therapeutic target for human lung cancer and overexpression of Pygo2 may be important for aberrant Wnt activation in lung cancer.

Objective: To explore the features of coronary atherosclerosis among the patients at different ages and examine their risk factors and pathological characteristics., Methods: Retrospective analysis was performed for the clinicopathologic data of 87 patients with coronary atherosclerosis confirmed through autopsy from February 1986 to December 2011 at our hospital. They were divided into 3 groups according to age (20 - < 40 years, n = 12; 40 - < 60 years, n = 24; ≥ 60 years, n = 51). Comparative analysis was performed for the degree of coronary artery stenosis and cardiac pathological changes, vulnerable plaque occurrence and morphological features of acute coronary syndrome among different patient groups., Results: There were 56 males and 31 females with a mean age of 66.8 years (range: 23 - 80). Great statistical differences existed in the degree of coronary artery stenosis between different genders (P < 0.05) while there was no significant difference among the above age groups (P > 0.05). In the above age groups of patients with acute coronary syndrome, the incidence of big lipid core was 23.5%, 38.5% and 53.8% (χ(2) = 6.282, P = 0.043), that of thin fibrous cap 29.4%, 41.0% and 58.8% (χ(2) = 6.589, P = 0.037), that of inflammatory cell in 2 filtration 58.8%, 69.2% and 85.0% (χ(2) = 7.435, P = 0.024) and that of calcification formation 35.3%, 56.4% and 71.3% respectively (χ(2) = 8.599, P = 0.014). And the incidence of vulnerable plaque occurrence was 76.5%, 84.6% and 88.8% (χ(2) = 1.850, P = 0.397) in the above age groups., Conclusions: The features and risk factors of coronary atherosclerosis are different according to different ages and genders. Thus we should pay more attention to the early diagnosis and reasonable treatments of young patients and those with both mild coronary stenosis and vulnerable plaque.