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91.
Cancer is a deadly disease worldwide, with an anticipated 19.3 million new cases and 10.0 million deaths occurring in 2020 according to GLOBOCAN 2020. It is well established that carcinogenesis and cancer development are strongly linked to genetic changes and post-translational modifications (PTMs). An important PTM process, ubiquitination, regulates every aspect of cellular activity, and the crucial enzymes in the ubiquitination process are E3 ubiquitin ligases (E3s) that affect substrate specificity and must therefore be carefully regulated. A surfeit of studies suggests that, among the E3 ubiquitin ligases, neuronal precursor cell-expressed developmentally downregulated 4 (NEDD4)/NEDD4-like E3 ligases show key functions in cellular processes by controlling subsequent protein degradation and substrate ubiquitination. In addition, it was demonstrated that NEDD4 mainly acts as an oncogene in various cancers, but also plays a tumor-suppressive role in some cancers. In this review, to comprehend the proper function of NEDD4 in cancer development, we summarize its function, both its tumor-suppressive and oncogenic role, in multiple types of malignancies. Moreover, we briefly explain the role of NEDD4 in carcinogenesis and progression, including cell survival, cell proliferation, autophagy, cell migration, invasion, metastasis, epithelial-mesenchymal transition (EMT), chemoresistance, and multiple signaling pathways. In addition, we briefly explain the significance of NEDD4 as a possible target for cancer treatment. Therefore, we conclude that targeting NEDD4 as a therapeutic method for treating human tumors could be a practical possibility.  相似文献   
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93.
Probe Station Placement for Robust Monitoring of Networks   总被引:1,自引:0,他引:1  
We address the problem of selecting probe station locations from where probes can be sent to monitor all the nodes in the network. Probe station placement involves instrumentation overhead. Hence, the number of probe stations should be minimal to reduce the deployment cost. Also, probe station placement should be such that the network can be monitored even in the presence of failures. We present algorithms to select locations of probe stations so that the entire network can be monitored for computing various performance metrics. We aim to find a minimal set of probe station nodes so as to minimize the instrumentation overhead. The algorithm presented provides robust monitoring in presence of node failures. We then present algorithms to make the solution resilient to probe station failures, and to deal with weakly connected nodes. We provide an experimental evaluation of the proposed algorithms through simulation results.
Adarshpal S. SethiEmail:
  相似文献   
94.
95.
This paper is concerned with the problem of production planning in a flexible manufacturing system consisting of a single or parallel failure-prone machines producing a number of different products. The objective is to choose the rates of production of the various products over time in order to meet their demands at the minimum long-run average cost of production and surplus. The analysis proceeds with a study of the corresponding problem with a discounted cost. It is shown using the vanishing discount approach for the average cost problem that the Hamilton-Jacobi-Bellman equation in terms of directional derivatives has a solution consisting of the minimal average cost and the so-called potential function. The result helps in establishing a verification theorem, and in specifying an optimal control policy in terms of the potential function. The results settle a hitherto open problem as well as generalize known results.  相似文献   
96.
Stability constants and thermodynamic parameters (e.g. ΔH0 and Δ0) have been determined for intermacromolecular complexes of methacrylic acid-methacrylamide and acrylic acid-acrylamide copolymers with poly(vinyl pyrrolidone) (PVP). The presence of nonionic units in the copolymers greatly enhances the stability of the complexes with PVP. The enthalpy and entropy changes of the systems with temperature have been interpreted in terms of various modes of interaction between the components.  相似文献   
97.
A 74-year-old woman was referred to our hospital with the chief complaints of pneumaturia, fecaluria and discharge of feces and urine from vagina. Fistulography on the vaginal side showed the presence of contrast medium both in the sigmoid colon and bladder. Colonoscopy revealed multiple diverticulosis of the sigmoid colon. Under diagnosis of colo-vesico-vaginal fistula due to sigmoid colon diverticulitis, a one-stage operation removing sigmoid colon, uterus-vaginal wall and urinary bladder wall including the fistula and careful reconstruction was performed. Postoperatively, urinary leakage from vagina in large amounts continued due to the recurrence of vesico-vaginal fistula. An attempt to use human fibrin glue in the recurrent fistula was successful, and the patient was asymptomatic at 21 months of follow-up. Colovesical fistula has been reported in about 10-20% of patients undergoing surgery for complicated diverticulitis, but a combined fistula is a rare condition. Furthermore, we recommend the use of human fibrin glue for a recurrent fistula.  相似文献   
98.
Feature point correspondence in the presence of occlusion   总被引:1,自引:0,他引:1  
Occlusion and poor feature point detection are two of the main difficulties in the use of multiple frames for establishing correspondence of feature points. A formulation of the correspondence problem as an optimization problem is used to handle these difficulties. Modifications to an existing iterative optimization procedure for solving the formulation of the correspondence problem are discussed. Experimental results are presented to show the merits of the formulation  相似文献   
99.
Areas of research on shock absorbing multiple supported and buried piping of nuclear power plants are recommended.  相似文献   
100.
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