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排序方式: 共有281条查询结果,搜索用时 15 毫秒
1.
Selwyn Arlington Headley Nayara Emily Viana Mariana de Mello Zanim Michelazzo Ana Aparecida Correa Xavier Cícero Júlio Silva Costa Felipe Hideki Ogo de Pinho Marcelo Diniz dos Santos 《Transboundary and Emerging Diseases》2020,67(Z2):49-59
Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2. 相似文献
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Takeshi Masaki Makoto Okazawa Ryotaro Asano Tadakatsu Inagaki Tomohiko Ishibashi Akiko Yamagishi Saori Umeki-Mizushima Manami Nishimura Yusuke Manabe Hatsue Ishibashi-Ueda Manabu Shirai Hirotsugu Tsuchimochi James T Pearson Atsushi Kumanogoh Yasushi Sakata Takeshi Ogo Tadamitsu Kishimoto Yoshikazu Nakaoka 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(11)
5.
Myeloid progenitor cells in the circulation of patients with myelofibrosis and other myeloproliferative disorders 总被引:4,自引:0,他引:4
J. A. Hibbin O. S. Njoku E. Matutes S. M. Lewis J. M. Goldman 《British journal of haematology》1984,57(3):495-503
We have measured the numbers of myeloid progenitor cells in the circulation of patients with myelofibrosis (MF) and other myeloproliferative disorders. In general, progenitor cell numbers were increased in the circulation of patients with MF compared with controls. The mean increases were 9-fold for the multilineage progenitor cells (CFU-GEMM), 13-fold for the erythroid progenitor cells (BFU-E), 37-fold for the granulocyte-macrophage progenitor cells (CFU-GM) and 167-fold for the megakaryocyte progenitors (CFU-MK). Splenectomized patients generally had reduced numbers of circulating progenitor cells. In the CFU-MK assay, mature megakaryocytes cultured from patients with MF regularly showed large vacuoles in the nucleus and cytoplasm, unlike control cells. The increased colony formation in patients with MK, involving especially CFU-MK colonies, is consistent with the hypothesis that MF is a primary myeloproliferative disorder in which a megakaryocyte-derived factor predisposes to the formation of marrow fibrosis. 相似文献
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Ayako Takahashi Reona Inagaki Maki Torimoto Yudai Hisai Taku Matsuda Quanbao Ma Jeong Gil Seo Takuma Higo Hideaki Tsuneki Shuhei Ogo Truls Norby Yasushi Sekine 《RSC advances》2020,10(25):14487
Catalytic methane steam reforming was conducted at low temperature using a Pd catalyst supported on Ce1−xMxO2 (x = 0 or 0.1, M = Ca, Ba, La, Y or Al) oxides with or without an electric field (EF). The effects of the catalyst support on catalytic activity and surface proton hopping were investigated. Results show that Pd/Al-CeO2 (Pd/Ce0.9Al0.1O2) showed higher activity than Pd/CeO2 with EF, although their activity was identical without EF. Thermogravimetry revealed a larger amount of H2O adsorbed onto Pd/Al-CeO2 than onto Pd/CeO2, so Al doping to CeO2 contributes to greater H2O adsorption. Furthermore, electrochemical conduction measurements of Pd/Al-CeO2 revealed a larger contribution of surface proton hopping than that for Pd/CeO2. This promotes the surface proton conductivity and catalytic activity during EF application.Temperature dependence of electron/ion conductivity of Pd/CeO2 and Pd/Al-CeO2 under wet conditions with application of an electric field. 相似文献
8.
Sickle cell anemia is a genetic disease characterized byan increase in generation of reactive oxygen species, abnormal iron release and low antioxidant activity which can lead to cell injury. Several therapies have been used to decrease the oxidative damage in these patients. In this study, we investigated the effect of flavonoids (quercetin and rutin) on the oxidation of red blood cells (RBC) from sickle cell anemia patients following exposure of the cells to tert-butyl hydroperoxide (t-BOOH). Quercetin provided greater protection against Hb oxidation, the binding of Hb to membrane and lipid peroxidation than did rutin. Quercetin (150 microM) reduced Hb oxidation by 30% and increased the level of oxyHb from 17.5 to 29 microM. Rutin prevented Hb oxidation only at concentrations higher than 200 microM and did not prevent the binding of Hb to RBC membrane. These distinct effects of the flavonoids probably reflect their structural characteristics. Thus, quercetin, which possesses a suitable structure for free-radical scavenging and ion quelation, was a more effective antioxidant than rutin. The presence of rutinose at position C(3) in rutin may impair its antioxidant effect. The presence of ascorbic acid enhanced the protective effect of quercetin and rutin against oxidative stress in sickle Hb and lipid peroxidation. This synergistic action helped to maintain a constant supply of flavonoids and thus, rescue the cells from the injury caused by free radicals and iron ions. 相似文献
9.
Antioxidant enzymes activity,lipid peroxidation,oxidative damage in the testis and epididymis,and steroidogenesis in rats after co‐exposure to atrazine and ethanol 下载免费PDF全文
Concomitant alcohol use and exposure to xenobiotics can adversely affect gonadal functions. This study investigated the oxidative status of the testis and epididymis and steroidogenesis of rats co‐exposed to ethanol (EtoH, 5 mg kg?1 b.wt.) and atrazine (ATZ, 50, 100, 300 mg kg?1 b.wt.) for 3 weeks. The activities of catalase, superoxide dismutase, glutathione peroxidase, as well as the concentrations of glutathione and malondialdehyde, as indicators of oxidative stress were measured in the homogenates of the testis and epididymis. Testosterone and cholesterol concentrations as well as 17β‐hydroxysteroid dehydrogenase (17β‐HSD) activity were assayed in the plasma and testis respectively. After the administration of EtoH alone, or in combination with different doses of ATZ, oxidative damage as evident by malondialdehyde level was not observed in both the testis and epididymis. The combine exposure group showed dose‐dependent decrease in plasma testosterone and testis cholesterol level and increase in testis 17β‐HSD activity compared to the EtoH group. Furthermore, the testes and epididymis of the EtoH‐exposed rats treated with high dose of ATZ had severe histopathological damage. Therefore, ATZ‐exposed alcohol‐treated rats have histological damage of the testis and epididymis and lower testosterone level than EtoH‐treated rats. 相似文献
10.
Njoku Isaac Omoke 《World journal of surgery》2016,40(8):1885-1891