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排序方式: 共有86条查询结果,搜索用时 15 毫秒
31.
Lenka Kalinkova Nataliia Nikolaieva Bozena Smolkova Sona Ciernikova Karol Kajo Vladimir Bella Viera Horvathova Kajabova Helena Kosnacova Gabriel Minarik Ivana Fridrichova 《International journal of molecular sciences》2022,23(1)
Background: Dissemination of breast cancer (BC) cells through the hematogenous or lymphogenous vessels leads to metastatic disease in one-third of BC patients. Therefore, we investigated the new prognostic features for invasion and metastasis. Methods: We evaluated the expression of miRNAs and epithelial-to-mesenchymal transition (EMT) genes in relation to CDH1/E-cadherin changes in samples from 31 patients with invasive ductal BC including tumor centrum (TU-C), tumor invasive front (TU-IF), lymph node metastasis (LNM), and CD45-depleted blood (CD45-DB). Expression of miRNA and mRNA was quantified by RT-PCR arrays and associations with clinico-pathological characteristics were statistically evaluated by univariate and multivariate analysis. Results: We did not verify CDH1 regulating associations previously described in cell lines. However, we did detect extremely high ZEB1 expression in LNMs from patients with distant metastasis, but without regulation by miR-205-5p. Considering the ZEB1 functions, this overexpression indicates enhancement of metastatic potential of lymphogenously disseminated BC cells. In CD45-DB samples, downregulated miR-205-5p was found in those expressing epithelial and/or mesenchymal markers (CTC+) that could contribute to insusceptibility and survival of hematogenously disseminated BC cells mediated by increased expression of several targets including ZEB1. Conclusions: miR-205-5p and potentially ZEB1 gene are promising candidates for markers of metastatic potential in ductal BC. 相似文献
32.
The present work explores the features of gate material engineered (GME) AlGaN/GaN high electron mobility transistor (HEMT) for enhanced carrier transport efficiency (CTE) and suppressed short channel effects (SCEs) using 2-D sub-threshold analysis and device simulation. The model accurately predicts the channel potential, electric field and sub-threshold current for the conventional and GME HEMT, taking into account the effect of work function difference of the two metal gates. This is verified by comparing the model results with the ATLAS simulation results. Further, simulation study has been extended to reflect the wide range of benefits exhibited by GME HEMT for its on-state and analog performance. The simulation results demonstrate that the GME HEMT exhibits much higher on current, lower conductance and higher transconductance as compared to the conventional HEMT due to improved CTE and reduced SCEs. This in turn has a direct bearing on the device figure of merits (FOMs) such as intrinsic gain, device efficiency and early voltage. Tuning of GME HEMT in terms of the relative lengths of the two metal gates, their work function difference and barrier layer thickness has further been carried out to enhance the drive current, transconductance and the device FOMs illustrating the superior performance of GME HEMT for future high-performance high-speed switching, digital and analog applications. 相似文献
33.
Coffman Sandra J.; Martell Christopher R.; Dimidjian Sona; Gallop Robert; Hollon Steven D. 《Canadian Metallurgical Quarterly》2007,75(4):531
In a recent placebo-controlled comparison, behavioral activation was superior to cognitive therapy in the treatment of moderate to severely depressed adults. Moreover, a subset of patients exhibited a pattern of extreme nonresponse to cognitive therapy on self-reports of depression not evident on the clinician ratings. These patients were severely depressed, functionally impaired, and had primary support group problems; most also described themselves as having life-long depressions. Comparable numbers of patients with such characteristics were assigned to behavioral activation, indicating that randomization did not fail, and most instances occurred in the context of adequate cognitive therapy. If this pattern of self-reported extreme nonresponse to cognitive therapy replicates, it would suggest that there might be a subset of patients who see themselves as doing better with sustained attention to behavior change in time-limited treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
Design equations are presented for calculating the resonance frequencies for a compact dual frequency arrow‐shaped microstrip antenna. This provides a fast and simple way to predict the resonant frequencies of the antenna. The antenna is also analyzed using the IE3D simulation package. The theoretical predictions are found to be very close to the IE3D results and thus establish the validity of the design formulae. © 2002 Wiley Periodicals, Inc. Int J RF and Microwave CAE 12, 477–482, 2002. Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mmce.10048 相似文献
35.
The endogenous oestrogen state in 52 women (33 with endometrial carcinoma and 19 with benign conditions of the endometrium) was assessed ny means of histological examinations of vaginal swabs and of radio-immunological determinations of 17 beta-oestradiol. Considering their age, these women displayed an oestrogen activity far exceeding that found in previous studies. There was no difference between the oestrogen levels in women with carcinoma and the other patients. Furthermore, it was stiking that in the same group of women the examined parameters frequently showed different results. Consequently, a diagnosis based solely on the investigation of one parameter must frequently be misleading. 相似文献
36.
A set of basic switching elements for performing logical operations on optical signals is considered. The devices are based on interferometric techniques associated with changes in optical paths introduced by electro-optical cells. It is shown that the most general switching function can be implemented without making recourse to any intermediate optical-to-electrical signal conversion. 相似文献
37.
Sona P. Kumar Anju Agrawal R.S. Gupta Mridula Gupta 《Microelectronics Reliability》2011,51(3):587-596
In the work proposed, linearity performance of dual material gate (DMG) AlGaN/GaN HEMT has been analyzed and compared with the corresponding performance of Single Material Gate (SMG) AlGaN/GaN HEMT using ATLAS device simulation. Specifically, we investigate the linearity of DMG and conventional AlGaN/GaN HEMT based on the linearity metrics such as gm, gm2, gm3, VIP2, VIP3, IIP3, IMD3 and 1-dB compression point. The impact of various device parameters on the device linearity such as the channel length, doping and thickness of the barrier and spacer layer, Al mole fraction and the work function difference of the two gate metals has also been investigated. It is observed that a suitably designed DMG AlGaN/GaN HEMT can considerably improve the linearity performance and minimize intermodulation distortion due to reduced drain induced barrier lowering and high-field effect; and a more uniform electric field for applications in 3-G mobile communication and low noise amplifiers. 相似文献
38.
Ivana Fridrichova Lenka Kalinkova Sona Ciernikova 《International journal of molecular sciences》2022,23(20)
Metastatic breast cancer (MBC) is typically an incurable disease with high mortality rates; thus, early identification of metastatic features and disease recurrence through precise biomarkers is crucial. Circulating tumor cells (CTCs) consisting of heterogeneous subpopulations with different morphology and genetic, epigenetic, and gene expression profiles represent promising candidate biomarkers for metastatic potential. The experimentally verified role of epithelial-to-mesenchymal transition in cancer dissemination has not been clearly described in BC patients, but the stemness features of CTCs strongly contributes to metastatic potency. Single CTCs have been shown to be protected in the bloodstream against recognition by the immune system through impaired interactions with T lymphocytes and NK cells, while associations of heterotypic CTC clusters with platelets, leucocytes, neutrophils, tumor-associated macrophages, and fibroblasts improve their tumorigenic behavior. In addition to single CTC and CTC cluster characteristics, we reviewed CTC evaluation methods and clinical studies in early and metastatic BCs. The variable CTC tests were developed based on specific principles and strategies. However, CTC count and the presence of CTC clusters were shown to be most clinically relevant in existing clinical trials. Despite the known progress in CTC research and sampling of BC patients, implementation of CTCs and CTC clusters in routine diagnostic and treatment strategies still requires improvement in detection sensitivity and precise molecular characterizations, focused predominantly on the role of CTC clusters for their higher metastatic potency. 相似文献
39.
40.
FLiNaK (LiF–NaF–KF: 46·5–11·5–42 mol.-%) is a promising candidate as high temperature coolant for next generation nuclear reactor coolants. Major technical challenge in implementation is the selection of structural material that can withstand corrosive nature of FLiNaK. Corrosion study of different alloys such as SS-316L, SS-317L, Inconel-625, Incoloy-800H, Hastelloy-B and Ni-201 was performed in FLiNaK salt. The tests were carried out in the temperature range of 650–850°C in graphite crucibles for 60 h under inert atmosphere. Weight loss of the alloy sample due to corrosion was measured, and corrosion rate was estimated. The salt composition after corrosion was analysed by inductively coupled plasma spectroscopy coupled with atomic emission spectroscopy. The surface morphology of the alloy samples was analysed by scanning electron microscopy. Ni-201 and Hastelloy-B showed better resistance to corrosion than other alloys. Corrosion rate was found to increase with increase in Cr content in the alloy. 相似文献