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排序方式: 共有4653条查询结果,搜索用时 31 毫秒
1.
Makoto Yamaguchi 《应用聚合物科学杂志》2021,138(14):50172
Perfluorosulfonic acid ionomer membranes have been widely used as proton conducting membranes in various electrochemical processes such as polymer electrolyte fuel cells and water electrolysis. While their thermal stability has been studied by thermogravimetry and analysis of low molecular weight products, their decomposition mechanism is little understood. In this study a newly developed methodology of thermal desorption and pyrolysis in combination with direct analysis in real time mass spectrometry is applied for Nafion membrane. An ambient ionization source and a high-resolution time-of-flight mass spectrometer enabled unambiguous assignment of gaseous products. Thermal decomposition is initiated by side chain detachment above 350°C, which leaves carbonyls on the main chain at the locations of the side chains. Perfluoroalkanes are released above 400°C by main chain scission and their further decomposition products dominate above 500 °C. DFT calculation of reaction energies and barrier heights of model compounds support proposed decomposition reactions. 相似文献
2.
Abidur Rahman Makoto Kobayashi Kotaro Sugimoto Yuta Endo Manabu Kojima Shigenori Furukawa Takafumi Watanabe Shu Soeda Yuko Hashimoto Keiya Fujimori Hideki Chiba 《International journal of molecular sciences》2021,22(7)
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases. 相似文献
3.
Aniruddha Nag Mohammed Asif Ali Jiabei Zhou Makoto Ogawa Tatsuo Kaneko 《大分子材料与工程》2021,306(11):2100459
Aromatic and functional polymers with processibility derived from biobased starting materials are prerequisite considering sustainable society. Poly(2,5-benzimidazole)s are rigid-rod polymers to show ultrahigh thermal stability such as flame retardance, while usually suffer from poor solubility. Here, poly(benzimidazole-co-amide)s are synthesized from two biobased monomers, 3,4-diaminobenzoic acid and a semirigid comonomer, 4-aminohydrocinnamic acid. The copolymers with an amide composition of 80 mol% and higher are soluble in widely used polar solvents to fabricate the films keeping high flame retardance, which is comparable with popular high-performance polymers such as aromatic polyimides, polyetheretherketone, polyphenylene sulfide, etc. 相似文献
4.
Takashi Ohnishi Yuki Ogawa Kota Suda Miki Komatsu Satoko Matsumoto Harmon Mitsuru Asukai Masahiko Takahata Norimasa Iwasaki Akio Minami 《International journal of molecular sciences》2021,22(9)
Pyogenic spondylodiscitis can cause severe osteolytic and destructive lesions in the spine. Elderly or immunocompromised individuals are particularly susceptible to infectious diseases; specifically, infections in the spine can impair the ability of the spine to support the trunk, causing patients to be bedridden, which can also severely affect the physical condition of patients. Although treatments for osteoporosis have been well studied, treatments for bone loss secondary to infection remain to be elucidated because they have pathological manifestations that are similar to but distinct from those of osteoporosis. Recently, we encountered a patient with severely osteolytic pyogenic spondylodiscitis who was treated with romosozumab and exhibited enhanced bone formation. Romosozumab stimulated canonical Wnt/β-catenin signaling, causing robust bone formation and the inhibition of bone resorption, which exceeded the bone loss secondary to infection. Bone loss due to infections involves the suppression of osteoblastogenesis by osteoblast apoptosis, which is induced by the nuclear factor-κB and mitogen-activated protein kinase pathways, and osteoclastogenesis with the receptor activator of the nuclear factor-κB ligand-receptor combination and subsequent activation of the nuclear factor of activated T cells cytoplasmic 1 and c-Fos. In this study, we review and discuss the molecular mechanisms of bone loss secondary to infection and analyze the efficacy of the medications for osteoporosis, focusing on romosozumab, teriparatide, denosumab, and bisphosphonates, in treating this pathological condition. 相似文献
5.
Liu Yong-Fang Matsumoto Hiroshi Gu Ming Zhou Xiao-Xuan Wu Yong-Hua Chen Zhi-Hao 《核技术(英文版)》2019,30(7):1-6
Longitudinal injection is a promising on-axis injection scheme for diffraction-limited storage rings. In the latest version of the Hefei advanced light source(HALS), both the dynamic aperture and momentum aperture have been optimized. A longitudinal injection scheme was investigated on the HALS using a doublefrequency radio frequency system. To evaluate the injection performance, various errors were considered. A series of tracking simulations were conducted, and the injection efficiency was obtained under different error levels. 相似文献
6.
Ohsaki Makoto Fujiwara Jun Takeda Fumiyoshi 《International Journal of Mechanics and Materials in Design》2020,16(4):883-896
International Journal of Mechanics and Materials in Design - A simple iterative method is presented for cutting pattern optimization of frame-supported and pneumatic membrane structures for... 相似文献
7.
8.
T Seya M Nomura Y Murakami NA Begum M Matsumoto S Nagasawa 《Canadian Metallurgical Quarterly》1998,1(5):809-816
OBJECT: In this retrospective study, the authors analyzed the frequency, anatomical distribution, and appearance of traumatic brain lesions in 42 patients in a posttraumatic persistent vegetative state. METHODS: Cerebral magnetic resonance (MR) imaging was used to detect the number of lesions, which ranged from as few as five to as many as 19, with a mean of 11 lesions. In all 42 cases there was evidence on MR imaging of diffuse axonal injury, and injury to the corpus callosum was detected in all patients. The second most common area of diffuse axonal injury involved the dorsolateral aspect of the rostral brainstem (74% of patients). In addition, 65% of these patients exhibited white matter injury in the corona radiata and the frontal and temporal lobes. Lesions to the basal ganglia or thalamus were seen in 52% and 40% of patients, respectively. Magnetic resonance imaging showed some evidence of cortical contusion in 48% of patients in this study; the frontal and temporal lobes were most frequently involved. Injury to the parahippocampal gyrus was detected in 45% of patients; in this subgroup there was an 80% incidence of contralateral peduncular lesions in the midbrain. The most common pattern of injury (74% in this series) was the combination of focal lesions of the corpus callosum and the dorsolateral brainstem. In patients with no evidence of diffuse axonal injury in the upper brainstem (26% in this series), callosal lesions were most often associated with basal ganglia lesions. Lesions of the corona radiata and lobar white matter were equally distributed in patients with or without dorsolateral brainstem injury. Moreover, cortical contusions and thalamic, parahippocampal, and cerebral peduncular lesions were also similarly distributed in both groups. CONCLUSIONS: The data indicate that diffuse axonal injury may be the major form of primary brain damage in the posttraumatic persistent vegetative state. In addition, the authors demonstrated in this study that MR imaging, in conjunction with a precise clinical correlation, may provide useful supportive information for the accurate diagnosis of a persistent vegetative state after traumatic brain injury. 相似文献
9.
J Matsumoto H Ogawa R Maeyama K Okudaira T Shinka T Kuhara I Matsumoto 《Canadian Metallurgical Quarterly》1997,38(8):950-953
PURPOSE: We evaluated the efficacy of direct hemoperfusion (DHP) for treatment of acute valproate (VPA) intoxication and speculate on the biochemical perturbations that suggest a mechanism of coma induced by VPA overdose. PATIENT AND METHODS: The comatose patient was hospitalized approximately 6 h after ingesting 18 g VPA. DHP, with 200 g activated charcoal, was performed for 6 h. The plasma concentrations of VPA and Glasgow coma scale scores after admission were estimated. Before and after DHP, urine samples were tested in serial fashion for VPA metabolites, organic acids, and acyl carnitine esters of fatty acids. RESULTS: Plasma VPA was efficiently adsorbed on activated charcoal. The patient's plasma concentration of VPA decreased from 471 microg/ml (2,830 microM) to 45 microg/ml (270 microM), at which point the patient became alert. The half-life (t1/2) of VPA was calculated as 4.4 h before DHP and as 1.8 h during DHP. Before DHP, lactate and VPA-glucuronide markedly increased in urine samples, but beta-keto-VPA, a major mitochondrial metabolite, was not detected. Urinary excretion of carnitine esters of medium chain (C8-C10) dicarboxylic acids was increased. After DHP, lactate and VPA-glucuronide decreased, but a significant amount of beta-keto-VPA was demonstrated. Carnitine esters of medium chain dicarboxylic acids were decreased. CONCLUSIONS: DHP with activated charcoal was effective treatment for the patient with acute VPA intoxication and coma. The onset of coma may have been related to inhibition of beta-oxidation in the mitochondria, which was reversible by elimination of plasma VPA by DHP. 相似文献
10.
We present simulation results of the vortex dynamics in a trapped Bose-Einstein condensate in the presence of a rotating optical
lattice. Changing the potential amplitude and the relative rotation frequency between the condensate and the optical lattice,
we find a rich variety of dynamical phases of vortices. In particular, when the optical lattice rotates faster than the condensate,
the competition between the pinning force and the interactions by nucleated interstitial vortices leads to the melting of
vortex lattice, yielding a vortex liquid phase. 相似文献