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排序方式: 共有532条查询结果,搜索用时 31 毫秒
121.
Jonas K. Kurzhals Gina Klee Victoria Hagelstein Detlef Zillikens Patrick Terheyden Ewan A. Langan 《International journal of molecular sciences》2022,23(18)
Despite the dramatic improvements in recurrence-free survival in patients with metastatic melanoma treated with immune checkpoint inhibitors (ICI), a number of patients develop metastases during adjuvant therapy. It is not currently possible to predict which patients are most likely to develop disease recurrence due to a lack of reliable biomarkers. Thus, we retrospectively analyzed the case records of all patients who commenced adjuvant ICI therapy between January 2018 and December 2021 in a single university skin cancer center (n = 46) (i) to determine the rates of disease recurrence, (ii) to examine the utility of established markers, and (iii) to examine whether re-challenge with immunotherapy resulted in clinical response. Twelve out of forty-six (26%) patients developed a relapse on adjuvant immunotherapy in our cohort, and the median time to relapse was 139 days. Adjuvant immunotherapy was continued in three patients. Of the twelve patients who developed recurrence during adjuvant immunotherapy, seven had further disease recurrence within the observation period, with a median time of 112 days after the first progress. There was no significant difference comparing early recurrence (<180 days after initiation) on adjuvant immunotherapy to late recurrence (>180 days after initiation) on adjuvant immunotherapy. Classical tumor markers, including serum lactate dehydrogenase (LDH) and S-100, were unreliable for the detection of disease recurrence. Baseline lymphocyte and eosinophil counts and those during immunotherapy were not associated with disease recurrence. Interestingly, patients with NRAS mutations were disproportionately represented (60%) in the patients who developed disease recurrence, suggesting that these patients should be closely monitored during adjuvant therapy. 相似文献
122.
InSug O-Sullivan Ranjan Kc Gurjit Singh Vaskar Das Kaige Ma Xin Li Fackson Mwale Gina Votta-Velis Benjamin Bruce Arivarasu Natarajan Anbazhagan Andre J. van Wijnen Hee-Jeong Im 《International journal of molecular sciences》2022,23(20)
Tropomyosin receptor kinase A (TrkA/NTRK1) is a high-affinity receptor for nerve growth factor (NGF), a potent pain mediator. NGF/TrkA signaling elevates synovial sensory neuronal distributions in the joints and causes osteoarthritis (OA) pain. We investigated the mechanisms of pain transmission as to whether peripheral sensory neurons are linked to the cellular plasticity in the dorsal root ganglia (DRG) and are critical for OA hyperalgesia. Sensory neuron-specific deletion of TrkA was achieved by tamoxifen injection in 4-week-old TrkAfl/fl;NaV1.8CreERT2 (Ntrk1 fl/fl;Scn10aCreERT2) mice. OA was induced by partial medial meniscectomy (PMM) in 12-week-old mice, and OA-pain-related behavior was analyzed for 12 weeks followed by comprehensive histopathological examinations. OA-associated joint pain was markedly improved without cartilage protection in sensory-neuron-specific conditional TrkA knock-out (cKO) mice. Alleviated hyperalgesia was associated with suppression of the NGF/TrkA pathway and reduced angiogenesis in fibroblast-like synovial cells. Elevated pain transmitters in the DRG of OA-induced mice were significantly diminished in sensory-neuron-specific TrkA cKO and global TrkA cKO mice. Spinal glial activity and brain-derived neurotropic factor (BDNF) were significantly increased in OA-induced mice but were substantially eliminated by sensory-neuron-specific deletion. Our results suggest that augmentation of NGF/TrkA signaling in the joint synovium and the peripheral sensory neurons facilitate pro-nociception and centralized pain sensitization. 相似文献
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125.
Alessandro Narduzzo Amalia Coldea Arzhang Ardavan John Singleton Luca Pardi Vasile Bercu Akane Akutsu-Sato Hiroki Akutsu Scott Turner Peter Day 《Journal of Low Temperature Physics》2006,142(3-4):585-588
We report a spin resonance study of the family of quasi-two-dimensional organic (super)conductors β”-(BEDT-TTF)4[(H3O)M(C2O4)3]S, where M is a 3d transition metal ion and S is a host solvent molecule. The spin systems for M = Cr3+ (S = 3/2) and M = Fe3+ (S = 5/2) are investigated by means of both resonant and field modulation techniques in the frequency range between 50 and
313 GHz. The role of the different solvent molecules in determining the degree of spin-orbit coupling and the local symmetry
at the metal ion site is established. The low temperature behaviour of intensities, positions and widths of the resonant lines
shows significant modifications of the spin-orbit coupling, and of the inter-and intra-ionic spin-spin inter actions. Despite
the onset of a weak antiferromagnetic internal field at low temperature, the ultimate narrowing of the lines suggests spin-lattice
interactions may still be the dominant relaxation process. Diamagnetic screening in the mixed state of the superconducting
samples for fields parallel to the quasi-two-dimensional layers induces additional lineshifts only below B = 2.5T and T =
4K, determining the threshold of full field penetration within the anion layers. 相似文献
126.
Focused ion beam (FIB) sputtering is used to shape a variety of cutting tools with dimensions in the 15–100 μm range and cutting edge radii of curvature of 40 nm. The shape of each microtool is controlled to a pre-specified geometry that includes rake and relief features. We demonstrate tools having rectangular, triangular, and other complex-shaped face designs. A double-triangle tip on one tool is unique and demonstrates the versatility of the fabrication process. The FIB technique allows observation of the tool during fabrication, and, thus, reproducible features are generated with sub-micron precision. Tools are made from tungsten carbide, high-speed tool steel, and single crystal diamond. Application of FIB-shaped tools in ultra-precision microgrooving tests shows that the cross-section of a machined groove is an excellent replication of the microtool face. Microgrooves on 40–150 μm pitch are cut into 3 mm diameter polymer rods, for groove arc lengths greater than 12 cm. The surface finish of machined features is also reported; groove roughness (Ra) is typically less than 0.2 μm. Ultra-precision machining of cylindrical substrates is extended to make bound metal microcoils having feature sizes of 20–40 μm. 相似文献
127.
Doina Jitca Horia Nicolai Teodorescu Vasile Apopei Florin Grigoras 《International Journal of Speech Technology》2002,5(3):227-235
The paper presents theoretical support for and describes the use of a fuzzy paradigm in implementing a TTS system for the Romanian language, employing a rule-based formant synthesizer. In the framework of classic TTS systems, we propose a new approach in order to improve formant trace computation, aiming at increasing synthetic speech perceptual quality. A fuzzy system is proposed for solving the problem of the phonemes that are prone to multi-definitions in rule-based speech synthesis. In the introductory section, we briefly present the background of the problem and our previous results in speech synthesis. In the second section, we deal with the problem of the context-dependent phonemes at the letter-to-sound module level of our TTS system. Then, we discuss the case of the phoneme /l/ and the solution adopted to define it for different contexts. A fuzzy system is associated with each parameter (denoted F1 and F2) to implement the results of the complete analysis of the phoneme /l/ behavior. The knowledge used in implementing the fuzzy module is acquired by natural speech analysis. In the third section, we exemplify the computation of the synthesis parameters F1 and F2 of the phoneme /l/ in the context of the two syllable sequences. The parameter values are contrasted with those obtained from the spectrogram analysis of the natural speech sequences. The last section presents the main conclusions and further research objectives. 相似文献
128.
Nanosensors: Localized Synthesis of Iron Oxide Nanowires and Fabrication of High Performance Nanosensors Based on a Single Fe2O3 Nanowire (Small 16/2017) 下载免费PDF全文
129.
Output‐based H2 optimal controllers for a class of discrete‐time stochastic linear systems with periodic coefficients 下载免费PDF全文
The aim of the paper is to present a design procedure of the optimal controller minimizing the H2‐type norm of discrete‐time stochastic linear systems with periodic coefficients simultaneously affected by a nonhomogeneous but periodic Markov chain and state and control multiplicative white noise perturbations. Firstly, two H2‐type norms for the linear stochastic systems under consideration were introduced. These H2‐type norms may be viewed as measures of the effect of the additive white noise perturbations on the regulated output of the considered system. Before deriving of the state space representation of the optimal controller, some useful formulae of the two H2‐type norms were obtained. These formulae are expressed in terms of periodic solutions of some suitable linear equations and are derived in the absence of some additional assumptions regarding the Markov chain other than the periodicity of the sequence of the transition probability matrices. Further, it is shown that the optimal H2 controller depends on the stabilizing solutions of some specific systems of coupled Riccati equations, which generalize the well‐known control and filtering equations from linear time invariant case. For the readers convenience, the paper presents iterative numerical algorithms for the computations of the stabilizing solutions of these Riccati type systems. The theoretical developments are illustrated by numerical examples. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
130.
Nanosensors: Multifunctional Materials: A Case Study of the Effects of Metal Doping on ZnO Tetrapods with Bismuth and Tin Oxides (Adv. Funct. Mater. 6/2017) 下载免费PDF全文