48 research outputs found

    The value of surgery in the patients with de novo stage â…£ breast cancer

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    Breast cancer is one of the common malignant tumors in the world. About 6% of the patients are de novo stage â…£ breast cancer, which is incurable. Traditionally, the role of surgery has been confined to relieving symptoms, improving quality of life and reducing tumor load. Nowadays, a multidisciplinary team is a prerequisite for optimal management, and patients with oligometastatic lesion always live for a long time. R0 resection of the primary and metastatic foci can extend the time of progression-free survival (PFS), which may bring survival benefits. Therefore, whether to perform surgery has become a hot clinical issue. This article deeply discussed extensively the surgical value in de novo stage â…£ breast cancer patients

    Study on the Impact of Production Agglomeration of China’s Aquatic Products on Export Competitiveness

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    This paper collects the data of China’s aquatic products from 2002 to 2018 and studies the relationship between the production agglomeration and export competitiveness of aquatic products. This paper calculates the production Concentration Rate (CR) which reflects the degree of agglomeration of aquatic products and the Revealed Comparative Advantage (RCA) index which reflects the export competitiveness of aquatic products, and then uses variable intercept model with fixed effects to empirically analyze the impact of production agglomeration of three main aquatic products (fish, crustacean and shellfish) on the export competitiveness. The results show that there is an obvious phenomenon of production agglomeration of aquatic products in China. Overall, the improvement of production agglomeration of aquatic products is conducive to the promotion of export competitiveness

    Does Agricultural Export Promote Nepalese Economic Growth? ARDL Approach Using Structural Break

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    This study examines the impact of agricultural export on the economic growth in Nepal for the time period of 1970-2015. In this analysis, researchers used the ARDL model using structural break to investigate the relationship between agricultural exports and economic growth in Nepal. Agricultural land, exchange rate, foreign direct investment, trade openness and agricultural environmental pollution have all been included in this analysis. According to estimates, ARDL, tend towards short-run relationship has been validated. Whereas, in the long-run relation we found negative relation. Furthermore, this study found that agricultural land is directly affecting economic growth. This study recommends policies that improve agricultural production and trade should be strongly pursued to help boost a country’s economic growt

    Effects of Swirling Strength of the Premixed Gas Flow on Pollutant Emission in a Heavy-Duty Gas Turbine

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    The combustion process and pollutant emission of an annular combustion chamber for a heavy-duty gas turbine were investigated by numerical method. The realizable k-ε model and finite rate/eddy dissipation model were adopted for calculations of turbulence and combustion. The effects of different swirling numbers of the double-swirler inlet on the temperature distribution and the thermal NOx formation in the combustion chamber were analyzed. The results show that the change of the swirling number of the outer swirling flow has a greater influence on the generation of the thermal NOx when compared with that of the inner swirling flow. The maximum average temperature of the central cross section of the combustor does not exceed 1760K. The average mass fraction of the generated thermal NOx at the exit decreases with the increasing outer swirling number. When the outer swirling number is less than 0.8, the generation of the thermal NOx is severe at the side wall of the combustion chamber

    Frequency-Bessel Transform Based Microtremor Survey Method and Its Engineering Application

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    The development and utilization of urban underground space depend heavily on an understanding of urban geological conditions. The microtremor survey method is essential in urban geological surveys due to its quickness, convenience, non-destructiveness, and interference resistance. Since only the fundamental dispersion curves of Rayleigh waves can be obtained by utilizing the spatial autocorrelation method, the inversion results have multiple solutions. To improve the accuracy of the microtremor survey, this study employed the frequency-Bessel transform to extract the fundamental and higher modes of dispersion information of Rayleigh waves from the microtremor data array and verified the effectiveness of this method by synthesizing theoretical microtremor signals. Additionally, taking into account the order identification challenges brought on by mode jumps or missing modes in the dispersion curve, this study processed a multi-mode dispersion curve based on the newly proposed inversion objective function coupled with a genetic algorithm to obtain a shallow surface S-wave velocity structure. Compared to the traditional inversion objective function, the new function presented in this study could address mode misidentification more effectively and improved the accuracy of inversion calculations. Finally, the applicability and dependability of the frequency-Bessel-transform-based microtremor survey method were evaluated in a practical engineering case

    Effects of Composite Electrode Structure on Performance of Intermediate-Temperature Solid Oxide Electrolysis Cell

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    The composite electrode structure plays an important role in the optimization of performance of the intermediate-temperature solid oxide electrolysis cell (IT-SOEC). However, the structural influence of the composite electrode on the performance of IT-SOEC is not clear. In this study, we developed a three-dimensional macroscale model coupled with the mesoscale model based on percolation theory. We describe the electrode structure on a mesoscopic scale, looking at the electrochemical reactions, flow, and mass transport inside an IT-SOEC unit with a composite electrode. The accuracy of this multi-scale model was verified by two groups of experimental data. We investigated the effects of operating pressure, volume fraction of the electrode phase, and particle diameter in the composite electrode on electrolysis reaction rate, overpotential, convection/diffusion flux, and hydrogen mole fraction. The results showed that the variation in the volume fraction of the electrode phase had opposite effects on the electrochemical reaction rate and multi-component diffusion inside the composite electrode. Meanwhile, an optimal range of 0.8–1 for the particle diameter ratio was favorable for hydrogen production. The analysis of IT-SOEC with composite electrodes using this multi-scale model enables the subsequent optimization of cell performance and composite electrode structure

    Effects of Composite Electrode Structure on Performance of Intermediate-Temperature Solid Oxide Electrolysis Cell

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    The composite electrode structure plays an important role in the optimization of performance of the intermediate-temperature solid oxide electrolysis cell (IT-SOEC). However, the structural influence of the composite electrode on the performance of IT-SOEC is not clear. In this study, we developed a three-dimensional macroscale model coupled with the mesoscale model based on percolation theory. We describe the electrode structure on a mesoscopic scale, looking at the electrochemical reactions, flow, and mass transport inside an IT-SOEC unit with a composite electrode. The accuracy of this multi-scale model was verified by two groups of experimental data. We investigated the effects of operating pressure, volume fraction of the electrode phase, and particle diameter in the composite electrode on electrolysis reaction rate, overpotential, convection/diffusion flux, and hydrogen mole fraction. The results showed that the variation in the volume fraction of the electrode phase had opposite effects on the electrochemical reaction rate and multi-component diffusion inside the composite electrode. Meanwhile, an optimal range of 0.8–1 for the particle diameter ratio was favorable for hydrogen production. The analysis of IT-SOEC with composite electrodes using this multi-scale model enables the subsequent optimization of cell performance and composite electrode structure

    Insulin-like growth factor-1 receptor gene expression is associated with survival in breast cancer: a comprehensive analysis of gene copy number, mRNA and protein expression

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    Insulin-like growth factor-1 receptor (IGF1R) plays a key role in the initiation and progression of breast cancer. However, its prognostic relevance to breast cancer patients has long been a matter of debate. In a series of 325 primary invasive breast cancer patients, we performed a comprehensive analysis of IGF1R at the levels of gene copy number, mRNA expression and protein expression. The relationship between the IGF1R status and the clinicopathological characteristics and prognosis was evaluated. IGF1R mRNA levels not only correlated with protein expression, but also significantly associated with several clinicopathological parameters and prognosis of the patients. Patients with low nuclear grade, negative axillary lymph node, positive hormone receptor, negative HER2, negative Ki67 and luminal subtype tumors showed higher level expression of IGF1R mRNA, which was shown to be a significant univariate parameter for both relapse free survival (RFS) and breast cancer specific survival (BCSS) as well as significant multivariate parameter for BCSS. IGF1R protein expression showed an association with a prolonged BCSS in univariate analysis. By contrast, IGF1R gene copy number did not correlated with mRNA and protein expression, and harbored no prognostic value. When studied in breast tumor subtype groups relatively, IGF1R mRNA level was still significantly associated with a better BCSS. Overall, our data indicated a correlation among IGF1R mRNA expression and protein expression in primary breast cancer. In particular, the IGF1R mRNA expression appeared to be a good prognostic marker either in the entire cohort or in the luminal subtype group. These data may serve as background information for IGF1R-targeted therapy

    N1-Guanyl-1,7-Diaminoheptane Sensitizes Estrogen Receptor Negative Breast Cancer Cells to Doxorubicin by Preventing Epithelial-Mesenchymal Transition through Inhibition of Eukaryotic Translation Initiation Factor 5A2 Activation

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    Background: Approximately 30% of breast cancer does not express the estrogen receptor (ER), which is necessary for endocrine-based therapy approaches. Many studies demonstrated that eukaryotic translation initiation factor 5A2 (eIF5A2) serves as a proliferation-related oncogene in tumorigenic processes. Methods: The present study used cell viability assays, EdU incorporation assays, western blot, and immunofluorescence to explore whether N1-guanyl-1,7-diaminoheptane (GC7), which inhibits eIF5A2 activation, exerts synergistic cytotoxicity with doxorubicin in breast cancer. Results: We found that GC7 enhanced doxorubicin cytotoxicity in ER-negative HCC1937 cells but had little effect in ER-positive MCF-7 and Bcap-37 cells. Administration of GC7 reversed the doxorubicin-induced epithelial-mesenchymal transition (EMT) in ER-negative breast cancer cells. Knockdown of eIF5A2 by siRNA inhibited the doxorubicin-induced EMT in ER-negative HCC1937 cells. Conclusion: These data demonstrated that GC7 combination therapy may enhance the therapeutic efficacy of doxorubicin in estrogen negative breast cancer cells by preventing EMT through inhibition of eIF5A2 activation

    Recent Advances in the Aging Microenvironment of Breast Cancer

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    Aging is one of the risk factors for advanced breast cancer. With the increasing trend toward population aging, it is important to study the effects of aging on breast cancer in depth. Cellular senescence and changes in the aging microenvironment in vivo are the basis for body aging and death. In this review, we focus on the influence of the aging microenvironment on breast cancer. Increased breast extracellular matrix stiffness in the aging breast extracellular matrix can promote the invasion of breast cancer cells. The role of senescence-associated secretory phenotypes (SASPs) such as interleukin-6 (IL-6), IL-8, and matrix metalloproteases (MMPs), in breast cancer cell proliferation, invasion, and metastasis is worthy of exploration. Furthermore, the impact of senescent fibroblasts, adipocytes, and endothelial cells on the mammary matrix is discussed in detail. We also list potential targets for senotherapeutics and senescence-inducing agents in the aging microenvironment of breast cancer. In conclusion, this review offers an overview of the influence of the aging microenvironment on breast cancer initiation and progression, with the aim of providing some directions for future research on the aging microenvironment in breast cancer
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