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排序方式: 共有871条查询结果,搜索用时 15 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
2.
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
3.
To evaluate an association between Helicobacter pylori (H. pylori) infection and chronic atrophic gastritis (CAG), an established precursor of gastric cancer, we performed a cross-sectional study using IgG antibody against H. pylori and pepsinogens of blood donors in four prefectures in Japan. Although a geographic correlation between the age-adjusted prevalence rates for H. pylori infection and those for CAG was not seen, the age-adjusted odds ratios (OR) of H. pylori infection for CAG were high in each area (around five for men and from four to 12.6 for women). The association between them weakened with advancing age; the ORs in the youngest age group (16-29 yrs) and in the oldest age group (50-64 yrs) were 12.5 and 2.8 for men, and 11.5 and 5.2 for women, respectively. These findings suggest that H. pylori infection is strongly associated with CAG, while there are some other factors interacting in the development of CAG. A prospective cohort study in which CAG and H. pylori infection are taken into account will be necessary to assess the risks of gastric cancer. 相似文献
4.
Keishi Sakamoto Atsushi Kasugai Masaki Tsuneoka Koji Takahashi Yukiharu Ikeda Tsuyoshi Imai Takashi Nagashima Mitsuru Ohta Tsuyoshi Kariya Kenichi Hayashi Yoshika Mitsunaka Yosuke Hirata Yasuyuki Itoh Yukio Okazaki 《Journal of Infrared, Millimeter and Terahertz Waves》1997,18(9):1637-1654
A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at PRF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at PRF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window. 相似文献
5.
H Nagasawa 《Canadian Metallurgical Quarterly》1993,106(2):295-300
1. The number of insect neuropeptides identified chemically grows rapidly and most important neuropeptides have already been characterized. After multi-year efforts Bombyx diapause hormone has recently been isolated and sequenced. 2. New approaches to search for new insect neuropeptides have been carried out by two groups of workers, which have succeeded in identifying several unique peptides. 3. cDNAs for more than 10 insect neuropeptides have been cloned and sequenced. It was found that two functionally distinct neuropeptides, Bombyx diapause hormone and pheromone biosynthesis activating neuropeptide, are encoded in a single gene. 相似文献
6.
7.
Complement activation generally does not occur on homologous cells. We observed C3 deposition on cultured human umbilical vein endothelial cells (HUVEC) when those which had died of apoptosis were treated with human serum. The C3 deposition on apoptotic HUVEC required Mg2+ but not Ca2+. In addition, the incubation of apoptotic HUVEC with purified C3, B, and D in the presence of Mg2+ resulted in C3 deposition. These results indicated that the C3 deposition on apoptotic HUVEC is mediated by the activation of the alternative complement pathway. C3 contains an intrachain thioester bond in the alpha chain (110 kDa) and upon activation to C3b, binds with membrane molecules by forming an ester or amide bond. Western blotting of reduced C3b-membrane molecule complexes, isolated from serum-treated apoptotic HUVEC by immunoprecipitation with anti-C3, revealed the covalent binding of C3b to several membrane molecules. Most of the C3b-membrane molecule complexes were cleaved by hydroxylamine, suggesting covalent binding via an ester bond. The molecular mass of the major alpha chain fragment released by hydroxylamine treatment was not 105 kDa but 68 kDa, which corresponds to the alpha 1 fragment of iC3b. These results indicate that most of the C3b on HUVEC was cleaved at its alpha' chain to yield iC3b, which consists of three disulfide-linked polypeptide chains and is a ligand of the complement receptor type 3 (CR3) of phagocytes. These results suggest that apoptotic HUVEC can activate the alternative pathway of the homologous complement and that the complement is related to the clearance of apoptotic cells by phagocytes. 相似文献
8.
K Kawano S Mori O Hirajima S Mitsuru T Natori 《Canadian Metallurgical Quarterly》1998,47(2):suppl 103-suppl 106
9.
A series of acrylic nonaqueous dispersions were prepared by using various kinds of butylated melamine–formaldehyde (BMF) resins as dispersant. The functional group composition of BMF to form stable dispersion was butoxy group more than 13 mol/BMF 1 mol, and methylol group ranged from 1 to 2.5 mol/BMF 1 mol. It is concluded that the anchoring of BMF to acrylic copolymer was due to the formation of covalent bond between methylol group in BMF and hydroxy group in acrylic copolymer. 相似文献
10.
The following double galvanic cell was assembled and the thermodynamic properties of liquid Bi-Na and Sn-Na alloys, and the ion selectivity of -alumina during coulometric titration, were investigated. Mo, Na(I)¦-alumina¦M-Na(I), Mo [I] M-Na(I)¦-alumina¦Au + Au2Na, Mo [II] (M = Bi or Sn) where M-Na(1) and Au + Au2Na were used as the common electrode and reference electrode, respectively. Sodium was coulometrically titrated through the -alumina electrolyte of cell I both ways, and the EMFs were measured. It was found that no ion-exchange reaction occurs between the liquid alloys and the -alumina, and only Na was transferred in the -alumina during coulometric titrations. The thermodynamic properties of liquid Sn-Na and Bi-Na alloys were found to be in agreement with the literature. 相似文献