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排序方式: 共有2254条查询结果,搜索用时 31 毫秒
1.
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
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In recent years, computer technology has made remarkable progress and a computer has become an indispensable tool for both engineers and scientists. In this article, utilization of computers in welding research is briefly summarized. Their use in numerical analysis is particularly discussed and applied to physical phenomena in molten pool, hydrogen diffusion and residual stresses due to welding. A comparison is made between theoretical and experimental results. 相似文献
4.
I Tohnai Y Goto Y Hayashi M Ueda T Kobayashi M Matsui 《Canadian Metallurgical Quarterly》1996,12(1):37-47
This study investigated the impact of Difficulty Level and Type of Suggestion upon the durability of posthypnotic suggestion over an 8-week period. Seventy-eight highly susceptible subjects selected by both the Harvard Group Scale of Hypnotic Susceptibility: Form A (HGSHS:A) and Stanford Hypnotic Scale of Susceptibility: Form C (SHSS:C) were assigned to six groups (two levels of Difficulty x three Types of Suggestion). S's were tested for posthypnotic suggestion at 1, 3, 6, and 8 weeks. A 2 x 3 x 4 (Difficulty x Suggestion x Time) factorial ANOVA was conducted, with Time treated as a repeated-measure. The outcome variable at each time was either pass or fail for relevant suggestion. We found a significant Time effect, a significant Difficulty effect, and a significant Time x Difficulty interaction. Fewer subjects passed the difficult suggestions than passed the easy suggestions; fewer passed suggestions at a latter time; and the decay in pass rate was more pronounced for the easy suggestion condition, due largely to the higher initial pass rate. Type of Suggestion was not significant, nor were any of the other interactions. Clinical implications were discussed. 相似文献
5.
Kawahito S. Ueda S. Ishida M. Nakamura T. Usui S. Nagaoka S. 《IEEE transactions on bio-medical engineering》1994,41(4):400-406
A CMOS integrated circuit for a noninvasive biological-signal telemetry system specified for use in medical and physiological studies of the influence of weightlessness in space is presented. The system can monitor multichannel (4 channels maximum) biological signals from multiple subjects (4 subjects maximum) in real time by using time multiplexing. A key technique so-called synchronized multiple-subject telemetry, to achieve multiple-subject telemetry has been proposed. This technique utilizes bidirectional optical transmissions with direct and scattered infrared lights between an observer and each of the subjects. An experimental CMOS IC to give a small light-weight low-power, and smart telemetry instrument for use on animals has been developed. This IC is for evaluating circuit blocks of the implantable monolithic telemetry instrument. The major circuit blocks include CMOS digital circuits for synchronization, subject selection and time multiplexing, analog circuits for pulse interval modulation, and other blocks such as a CMOS optical pulse receiver and an LED driver. A preliminary experimental multichannel telemetry from two subjects has been performed with the implemented IC chips, and the principal operation of the multiple-subject optical biotelemetry has been demonstrated 相似文献
6.
The supercharged flap is one which is expected to attain better survival, by anastomosing the distal vessels of the flap to the recipient vessels. An experimental study is reported to determine whether the vessel to be anastomosed should be an artery, a vein, or both. The authors advise anastomosing an artery and a vein, but they believe that arterial inflow is more important than venous drainage. 相似文献
7.
Kenji Nomura Hiromichi OhtaKazushige Ueda Toshio Kamiya Masahiro HiranoHideo Hosono 《Thin solid films》2003,445(2):322-326
We have investigated the characteristics of transparent metal-insulator-semiconductor field-effect transistors (MISFETs) fabricated using InGaO3(ZnO)m (m=integer) single-crystalline thin films as n-channel layers and amorphous alumina as gate insulator films. The MISFETs exhibit good characteristics such as insensitivity to visible light illumination, off-current as low as ∼1 nA with a positive threshold voltage of ∼3 V and on/off current ratio of 105. The field-effect mobility increased from ∼1 to ∼10 cm2 (V s)−1 as the m-value increased. Room temperature Hall mobility also increased. However, unexpectedly these values were lower than the field-effect mobility. It is explained by existence of shallow localized state in the homologous compounds. 相似文献
8.
Preliminary experiments using two chemicals (CaO, a quicklime, and a cationic nitrogen-bearing precipitant, EC-004) to remove silica from geothermal brine were undertaken at the Mokai geothermal plant, New Zealand. The brine was mixed with the reagent (CaO or EC-004). The reaction was studied from the start of the experiment (NRT, 0 min, no retaining time) and after 15 min (15RT) at 90 °C. The concentration of silica in the brine was initially 954 mg/l, and decreased linearly with increasing reagent concentration. When CaO is added, the silica concentration at 15RT was 200 mg/l lower than at NRT and became almost zero on addition of 1.5 g/l. In contrast, when EC-004 is added, the total silica concentration nearly reaches the solubility of amorphous silica at 90 °C. In order to prevent silica scaling in Mokai brines cooled to 90 °C, the CaO and EC-004 added should be individually adjusted to 0.5 g/l and 80 mg/l, respectively. 相似文献
9.
T Doi S Takemura H Onodera M Ueda M Deguchi R Nakahara N Ichio S Nakanishi N Seto K Yanagida M Kondo 《Canadian Metallurgical Quarterly》1997,46(11):1108-1113
One of the anaphylatoxins, C5a, is known to increase the expression of the complement receptors, CR1 and CR3, on PMNs which play important roles in the phagocytosis. We measured the expression of these receptors before and after the stimulation with C5a and C5a-receptors (C5aR) on PMNs in patients with systemic lupus erythematosus (SLE). PMNs from 16 patients and 11 normal controls were tested. All the patients with SLE were administered with prednisolone orally and were in the inactive stage. The CR1 expression in SLE was significantly weak (p < 0.01) before and after stimulation with 4.55 nM (50 micrograms/ml) of C5a. There was no significant difference of CR3 expression before stimulation. However, after the stimulation with C5a, the increase of CR3 on PMNs from SLE was significantly small (p < 0.01). C5aR on PMNs showed no difference between the two groups. However, the expression of C5aR was significantly suppressed in patients treated with a high dosage of prednisolone (> = 10 mg/day) compared to those with a low dosage of prednisolone (< 10 mg/day). There was no significant difference of CR1 and CR3 expression between these groups. It is concluded that the increase of CR1 and CR3 on PMNs by C5a in small in SLE, of which impaired increase is not due to C5aR on PMNs, and that the expression of C5aR is suppressed by prednisolone. 相似文献
10.
The major envelope protein, p35, of vaccinia virus (VV; strain LIVP) was purified by extraction from virions with the non-ionic detergent Nonidet P-40. The protein was cleaved with CNBr. Four homogeneous peptides were isolated and their N-terminal amino-acid (aa) sequences determined. A computer search of a protein sequence databank revealed complete identity of the determined sequences with aa 44-63, 144-149, 154-165 and 224-238 of ORF H3 of the HindIII-H fragment of the VV genome [Rosel et al., J. Virol. 60 (1989) 436-446]. Earlier, Gordon et al. [Virology 167 (1988) 361-369] determined that the p35 surface protein of VV strain IHD-W is encoded by the H6 gene. Muravlev et al. [Biopolymery i kletka 6 (1990) 83-89 (Russian)] deduced from their data that gene A2 encodes this prominent antigen. Taking into account this ambiguity, we cloned the genes H3, H6 and A2 in expression vectors, prepared the specific antisera against the expression products and conducted the immunochemical analysis of the recombinant and native VV-specific proteins. It has been established that the H6 codes for an early protein that is found only in the infected cell extracts, but is absent in mature virions. The immunodominant protein p35 of VV strain LIVP is encoded by the gene H3. The gene A2 protein product is present mainly in the infected cell extract, but the antiserum against the A2 product shows a rather weak interaction with the 35-kDa fraction of structural VV proteins resolved by electrophoresis. 相似文献