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排序方式: 共有239条查询结果,搜索用时 15 毫秒
91.
Saroj Rajthala Anjie Min Himalaya Parajuli Kala Chand Debnath Borghild Ljkjel Kristin Marie Hoven Arild Kvalheim Stein Lybak Evelyn Neppelberg Olav Karsten Vintermyr Anne Christine Johannessen Dipak Sapkota Daniela Elena Costea 《International journal of molecular sciences》2021,22(21)
Background: Knowledge on the role of miR changes in tumor stroma for cancer progression is limited. This study aimed to investigate the role of miR dysregulation in cancer-associated fibroblasts (CAFs) in oral squamous cell carcinoma (OSCC). Methodology: CAF and normal oral fibroblasts (NOFs) were isolated from biopsies of OSCC patients and healthy individuals after informed consent and grown in 3D collagen gels. Total RNA was extracted. Global miR expression was profiled using Illumina version 2 panels. The functional impact of altered miR-204 expression in fibroblasts on their phenotype and molecular profile was investigated using mimics and inhibitors of miR-204. Further, the impact of miR-204 expression in fibroblasts on invasion of adjacent OSCC cells was assessed in 3D-organotypic co-cultures. Results: Unsupervised hierarchical clustering for global miR expression resulted in separate clusters for CAF and NOF. SAM analysis identified differential expression of twelve miRs between CAF and NOF. Modulation of miR-204 expression did not affect fibroblast cell proliferation, but resulted in changes in the motility phenotype, expression of various motility-related molecules, and invasion of the adjacent OSCC cells. 3′ UTR miR target reporter assay showed ITGA11 to be a direct target of miR-204. Conclusions: This study identifies differentially expressed miRs in stromal fibroblasts of OSCC lesions compared with normal oral mucosa and it reveals that one of the significantly downregulated miRs in CAF, miR-204, has a tumor-suppressive function through inhibition of fibroblast migration by modulating the expression of several different molecules in addition to directly targeting ITGA11. 相似文献
92.
Zhenjing Duan Changhe Li Wenfeng Ding Yanbin Zhang Min Yang Teng Gao Huajun Cao Xuefeng Xu Dazhong Wang Cong Mao Hao Nan Li Gupta Munish Kumar Zafar Said Sujan Debnath Muhammad Jamil Hafiz Muhammad Ali 《机械工程学报(英文版)》2021,34(1):54-88
Aluminum alloy is the main structural material of aircraft,launch vehicle,spaceship,and space station and is pro-cessed by milling.However,tool wear and vibration are the bottlenecks in the milling process of aviation aluminum alloy.The machining accuracy and surface quality of aluminum alloy milling depend on the cutting parameters,material mechanical properties,machine tools,and other parameters.In particular,milling force is the crucial factor to determine material removal and workpiece surface integrity.However,establishing the prediction model of milling force is important and difficult because milling force is the result of multiparameter coupling of process system.The research progress of cutting force model is reviewed from three modeling methods:empirical model,finite element simulation,and instantaneous milling force model.The problems of cutting force modeling are also determined.In view of these problems,the future work direction is proposed in the following four aspects:(1)high-speed milling is adopted for the thin-walled structure of large aviation with large cutting depth,which easily produces high residual stress.The residual stress should be analyzed under this particular condition.(2)Multiple factors(e.g.,eccentric swing milling parameters,lubrication conditions,tools,tool and workpiece deformation,and size effect)should be consid-ered comprehensively when modeling instantaneous milling forces,especially for micro milling and complex surface machining.(3)The database of milling force model,including the corresponding workpiece materials,working condi-tion,cutting tools(geometric figures and coatings),and other parameters,should be established.(4)The effect of chatter on the prediction accuracy of milling force cannot be ignored in thin-walled workpiece milling.(5)The cutting force of aviation aluminum alloy milling under the condition of minimum quantity lubrication(mql)and nanofluid mql should be predicted. 相似文献
93.
Akash Kumar Anindya Debnath Antar Banik Kabirul Islam Mondal Partha Pratim Biswas Rik Bhattacharyya T K Maiti 《测试科学与仪器》2020,(2):193-196
介绍了一种基于定时器的转速测量系统的设计与开发。使用直流电动机的转轴来测量其转速,定时器IC 555用于不稳定模式。使用数字存储示波器(DSO)测量的定时器输出波形的频率几乎与转轴的转速成线性比例,而这个转速又与外部输入电压水平的变化成线性关系,由此得到了定时器输出波形频率与转速之间的线性关系。该系统的主要优点是线性输入-输出,体积小,便于携带且成本低。 相似文献
94.
95.
AR Neurath AK Debnath N Strick YY Li K Lin S Jiang 《Canadian Metallurgical Quarterly》1995,8(5):304-316
An evaluation of the effects of the ABLE (Analyzing Behavior State and Learning Environments) model was presented. Eight teachers received training on observing behavior state and relevant environmental variables; analyzing potential effects of nutrition and medications; identifying strategies for individual students; and participating in a process to generate classroom-based intervention strategies based on their observations. Results showed that teachers were able to reliably implement the model, which produced significant increases in occurrences of the preferred alert and active states and significant decreases in nonpreferred states, such as sleep, drowse, daze, and crying/agitated. Additional findings indicated that the teachers were satisfied with the training procedures and found the model to be relevant and appropriate for students with profound mental retardation. Case studies were briefly presented. 相似文献
96.
Jasim Ahmed U.S. Shivhare & S. Debnath 《International Journal of Food Science & Technology》2002,37(1):57-63
The kinetics of degradation of both green- and total-colour of green chilli puree was studied at selected temperatures (50–90 °C). A fractional conversion concept was applied to determine the kinetic parameters. The degradation of green- and total-colour followed first order reaction kinetics. In the case of green colour the data was based on changes in Hunter – a value while L × a × b was found to adequately represent total colour change. Dependence of the rate constant during heat treatment obeyed the Arrhenius relationship. The activation energy values for green- and total-colour degradation were 23.04 and 25.02 kJ mol–1 , respectively. These results indicated that total colour should be used as the quality indicator during thermal processing of green chilli puree. The pungency of green chilli puree decreased during thermal processing as the capsaicin content was reduced from 559 to 441 μg g–1 while the Scoville heat unit decreased from 8500 to 7480. The puree behaved as a shear-thinning fluid and the flow activation energy at 100 r.p.m. equalled 19.22 kJ mol–1 . 相似文献
97.
98.
S. Shirotori K. Kayanuma T. Tomita Z. H. Chen M. C. Debnath I. Souma A. Murayama Y. Oka 《Journal of Superconductivity》2003,16(2):457-460
Magnetic-field-induced level crossing and the spin dynamics of excitons in a Zn1–x
Mn
x
Te/ZnTe single quantum well are studied. The circularly-polarized photoluminescence (PL) shows that the down spin branch of the Zn1–x
Mn
x
Te exciton overlaps with both the up and down spin branches of the ZnTe exciton at a crossing field (H
c) of 4 T, due to the giant Zeeman shift of Zn1–x
Mn
x
Te. The PL intensities and lifetimes in each layer become gradually equal toward H
c, which shows the mixing of wavefunctions of the excitons generated in each layer. Above H
c, each branch of the spin-polarized exciton separates again. The lifetimes of the spin-polarized exciton PL reflect the spin-flip relaxation in ZnTe and the spin mixing between Zn1–x
Mn
x
Te and ZnTe layers. 相似文献
99.
100.
Nipa Debnath Takahiko Kawaguchi Harinarayan Das Shogo Suzuki Wataru Kumasaka Naonori Sakamoto 《Science and Technology of Advanced Materials》2018,19(1):507-516
In this study, we report about the occurrence of phase separation through spinodal decomposition (SD) in spinel manganese ferrite (Mn ferrite) thin films grown by Dynamic Aurora pulsed laser deposition. The driving force behind this SD in Mn ferrite films is considered to be an ion-impingement-enhanced diffusion that is induced by the application of magnetic field during film growth. The phase separation to Mn-rich and Fe-rich phases in Mn ferrite films is confirmed from the Bragg’s peak splitting and the appearance of the patterned checkerboard-like domain in the surface. In the cross-sectional microstructure analysis, the distribution of Mn and Fe-signals alternately changes along the lateral (x and y) directions, while it is almost homogeneous in the z-direction. The result suggests that columnar-type phase separation occurs by the up-hill diffusion only along the in-plane directions. The propagation of a quasi-sinusoidal compositional wave in the lateral directions is confirmed from spatially resolved chemical composition analysis, which strongly demonstrates the occurrence of phase separation via SD. It is also found that the composition of Mn-rich and Fe-rich phases in phase-separated Mn ferrite thin films deposited at higher growth temperature and in situ magnetic field does not depend on the corresponding average film composition. 相似文献