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Tsutomu Okamoto Keishi Ueda Takeshi Kambara Tatsuo Kutsuna 《Pathology international》1986,36(8):1109-1122
In order to why polymorphonuclear leukocytes (PMNs) are predominant and mononuclear leukocytes (MNLs) are few in rheumatoid synovial fluids, chemotactic factor(s) for PMNs and MNLs were studied in the synovial fluids of rheumatoid arthritis (RA-SF) and osteoarthritis (OA-SF) using both Boyden's and agarose methods. The RA-SF showed strong chemotactic activity for human peripheral blood PMNs compared with non-rheumatoid OA-SF. The chemotactic activity for PMNs was well correlated with the number of PMNs in RA-SF, suggesting that it was a natural mediator for PMN emigration into rheumatoid joint cavity. The major chemotactic factor for PMN in RA-SF was of apparent molecular weight of 14,000 and its activity was suppressed to less than 10 percent by anti-C5a antibody, but it failed to show any anaphylatoxin activity which was an attribute of C5a. It was, therefore, suggested to be C5a-like molecule but not C5a itself. The possibility that the factor may be a C5a des-Arg was discussed. On the contrary, the chemotactic activity for MNLs was not found neither in RA-SF nor OA-SF. These findings may explain the fact that PMNs are predominant in rheumatoid synovial fluids. 相似文献
44.
Takahashi Toshinari Beppu Takanobu Hidaka Yuji Hosoya Tatsuo 《Clinical and experimental nephrology》2021,25(12):1336-1345
Clinical and Experimental Nephrology - Dotinurad is a selective urate reabsorption inhibitor (SURI), which selectively inhibits URAT1 to lower serum uric acid levels in patients with hyperuricemia.... 相似文献
45.
A. Sadato W. Taki Y. Ikada I. Nakahara K. Yamashita K. Matsumoto M. Tanaka H. Kikuchi Y. Doi T. Noguchi T. Inada 《Neuroradiology》1994,36(8):634-641
A new material, an emulsion of poly(vinyl acetate) was experimentally developed and clinically used to overcome several disadvantages in currently used liquid embolisation materials. The emulsion microparticles, 0.3–0.7 m in size, possessed cationic charge on the surface and hence aggregated immediately on contact with fluids containing anions. This inert polymer has the advantage that it does not induce a deleterious reaction in living tissue. Moreover, its medium is water and it is not adhesive, like the cyanoacrylates. Several concentrations of emulsion were injected into the renal arteries of dogs. For the investigation of tissue reactions and the possibility of recanalisation, the emulsion was injected into rats both subcutaneously and into the renal arteries. The renal artery injections in dogs showed adequate radiopacity and consistent complete occlusion. The lower the concentration of the emulsion, the smaller the arteries which could be occluded. Even at very low concentrations, however, venous occlusion did not occur. Histological study of the embolised rat kidney revealed no detectable damage in the vessel wall and no recanalisation for up to 6 months. The subcutaneously injected PVAc emulsion elicited mononuclear cell infiltration and gradual centripetal fibrosis, without any deleterious effect on the surrounding tissue. A cerebral arteriovenous malformation (AVM) was embolised using the material. Histology of the resected nidus showed findings similar to those in the animal experiments. 相似文献
46.
CONTEXT: Pregnant women are exempted from the current seatbelt legislation in Japan despite the fact that seatbelt use is essential to reduce the risk of fatalities for these women and their fetuses in car crashes. OBJECTIVE: To examine factors that might influence seatbelt use during pregnancy. METHODS: A cross sectional study, with data collected via an anonymous, self administered questionnaire at obstetric clinics in suburban areas of Japan. Altogether 880 pregnant women receiving prenatal care in July 2001 were recruited. The relative effects of factors that might influence seatbelt use during pregnancy were estimated using logistic regression analysis. RESULTS: Almost 70%-80% of pregnant women were consistent seatbelt wearers before pregnancy but seatbelt compliance was reduced by about half at 20 weeks or more gestation. Only 20% had received information on maternal seatbelt use, with one third reporting that seatbelt use is beneficial during pregnancy. Those who perceived that maternal seatbelt use is beneficial tended to maintain use, but daily car users and those who knew that they were exempted from seatbelt legislation were more likely to reduce use. CONCLUSIONS: Knowledge of the legislative exemption for pregnant women, misunderstanding of the benefits, and daily car use contributed to the reduction in seatbelt use after pregnancy. 相似文献
47.
The role of the sentinel lymph node in gastrointestinal cancer 总被引:38,自引:0,他引:38
Kitagawa Y Fujii H Mukai M Kubota T Ando N Watanabe M Ohgami M Otani Y Ozawa S Hasegawa H Furukawa T Kumai K Ikeda T Nakahara T Kubo A Kitajima M 《The Surgical clinics of North America》2000,80(6):1799-1809
Evaluation of the clinical significance of the sentinel node concept in GI cancer has just begun. The authors' preliminary data, using intraoperative radiation techniques and the gamma probe, suggest that it is worthwhile to continue the evaluation of this procedure to determine its role in an accurate staging and a minimally invasive approach to GI cancers. 相似文献
48.
Pelvic insufficiency fractures in postmenopausal woman with advanced cervical cancer treated by radiotherapy. 总被引:3,自引:0,他引:3
Ichiro Ogino Naoyuki Okamoto Yoshimi Ono Tatsuo Kitamura Hiroki Nakayama 《Radiotherapy and oncology》2003,68(1):61-67
PURPOSE: To assess the predisposing factors and clinical characteristics of pelvic insufficiency fractures (PIF) in postmenopausal women with pelvic irradiation. MATERIAL AND METHODS: A total 335 postmenopausal patients with cervical cancer of the intact uterus treated with radiation therapy between 1983 and 1998 were reviewed. Total external dose was delivered between 45 and 50.4 Gy with parallel opposed anteroposterior portals. Total brachytherapy dose at point A was delivered between 10 and 36 Gy. PIF were diagnosed by bone scintigraphy and confirmed by computed tomography. The cumulative incidence of symptomatic PIF was estimated by actuarial methods. Potential risk factors (age, weight, type II diabetes, delivery, menopause, total external dose, total brachytherapy dose) were assessed. RESULTS: Fifty-seven (17.0%) of 335 patients were diagnosed as having PIF. Forty-seven patients were symptomatic and ten were asymptomatic. Parameters carrying a significant association with PIF were body weight 49 kg or below (P=0.044) in stepwise logistic regression analysis. The cumulative incidence of symptomatic PIF at 5 years was 17.9% calculated by the Kaplan-Meier method. A body weight of 49 kg or below and more than three deliveries were identified as having a significant effect on symptomatic PIF in univariate analysis (P=0.021, P=0.003, log-rank test) and Cox life table regression analysis (P=0.038, P=0.013). Five patients required narcotic agents and eight patients required hospital admission. CONCLUSIONS: We should consider reducing the dose contribution to the sacrum and sacroilac joints, without underdosing the tumor, especially in postmenopausal women with many deliveries or low body weight. 相似文献
49.
Induction of apoptosis in multi-drug resistant (MDR) human glioblastoma cells by SN-38, a metabolite of the camptothecin derivative CPT-11 总被引:5,自引:0,他引:5
Shouji Nakatsu S. Kondo Yasuko Kondo Dali Yin John W. Peterson Rami Kaakaji Tatsuo Morimura Haruhiko Kikuchi Juji Takeuchi Gene H. Barnett 《Cancer chemotherapy and pharmacology》1997,39(5):417-423
The overexpression of the multidrug resistance (mdr1) gene and its product, P-glycoprotein (P-gp), is thought to limit the successful chemotherapy of human tumors. Recent studies
demonstrate that SN-38, a metabolite of the camptothecin (CPT) derivative CPT-11, has antitumor effects on several tumors,
but the mechanisms responsible for its cytotoxicity remain unclear. We therefore determined whether SN-38 has cytotoxic effects
on MDR human glioblastoma GB-1 cells and non-MDR human glioblastoma U87-MG cells. Furthermore, we determined what role SN-38
plays in the induction of cytotoxicity in these tumor cells. In this study, we demonstrated that SN-38 had significantly stronger
antitumor effects on GB-1 and U-87MG cells than did CPT (P<0.01 and P<0.05, respectively). In addition, findings obtained using a DNA fragmentation assay, Hoechst 33258 staining, in situ end-labeling
and cell cycle analysis demonstrated that SN-38 induced apoptosis in these tumors. Our results suggest that SN-38 has a stronger
antitumor effect on malignant glioma cells regardless of MDR expression than does CPT, and therefore can be considered a new
chemotherapeutic agent potentially effective in the treatment of human primary or recurrent malignant gliomas resistant to
chemotherapy.
Received: 6 October 1995/Accepted 29 June 1996 相似文献
50.
Hiroyuki Shimizu i Utama Napa Onnimala Chen Li Zhang Li-Bi Ma Yu-Jie Yaowapa Pongsuwanna Tatsuo Miyamura 《Pediatrics international》2004,46(2):231-235
BACKGROUND: Recently, there have been large outbreaks of hand, foot and mouth disease (HFMD) mainly caused by enterovirus 71 (EV71) associated with severe neurological diseases in the Western Pacific Region (WPR). To monitor the realtime trend of EV71 transmission throughout the WPR, the authors conducted a molecular epidemiological analysis of EV71 infection. METHODS: Viruses were isolated from clinical samples from patients with HFMD or those with neurological complications. The EV71 isolates were identified by microneutralization assay. The VP4 and/or VP1 regions of recent EV71 isolates were sequenced and subjected to phylogenetic analysis using reference EV71 strains. RESULTS: The phylogenetic analysis of EV71 isolates from the WPR revealed two major genogroups, B and C, based on the nucleotide sequence alignment of the VP1 or VP4 region. These two major genogroups were further divided into subgenogroups, B1, B2, B3, and B4 and C1, C2, C3 and C4, respectively. CONCLUSIONS: The molecular epidemiological analyses of recent and previous EV71 isolates in the WPR indicated that two major genogroups of EV71 are co-circulating in Australia, Malaysia, Singapore, Taiwan and Japan. Recent EV71 isolates in Mainland China constitute a new distinct genetic cluster, subgenogroup C4. Two major lineages of EV71 are the major causative agents of the present HFMD epidemics in the WPR and both are considered to be neurovirulent. 相似文献