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111.
Chronic infection/inflammation of the urinary tract is a significant risk factor for the development of bladder cancer. The present study examined the hypothesis that hydrogen peroxide (H202) and cytokines released during inflammation are involved in the enhancement of bladder carcinogenesis. Using growth in soft agar and tumorigenicity in athymic nude mice as indices of transformation, we examined the effect of H202 and cytokines on the enhancement of N-methyl-N-nitrosourea (MNU)-initiated transformation of MYP3 cells, an anchorage-dependent nontumorigenic rat bladder epithelial cell line. MYP3 cells pretreated with or without MNU were exposed to H202 (0.001 to 0.1 mM) daily for 1 week in monolayer culture and were then tested for growth in soft agar. A marked increase in colony numbers was observed in the cells that were MNU-initiated and exposed to H202 (P < 0.01). Furthermore, H202 exposure alone at 0.01 mM or 0.1 mM caused colony formation in soft agar. The transformants induced by MNU plus H202 or H202 alone formed high-grade transitional cell carcinomas when injected into nude mice. The growth of these transformants was stimulated by several cytokines (interleukin 1alpha, interleukin 6, and tumor necrosis factor-alpha) better than the parental cells both on a plastic surface and in soft agar. Our results indicate that H202 causes genetic change(s) to induce tumorigenic conversion in urothelial cells and that the transformants are stimulated to grow because of their selective response to several cytokines. We suggest that these mechanisms may be involved in the in vivo carcinogenesis associated with chronic urinary tract infection. 相似文献
112.
Y Hayakawa R Kawai K Otsuki M Kataoka A Matsuda 《Canadian Metallurgical Quarterly》1998,8(18):2559-2562
To investigate the stability of 2'-C-cyano-2'-deoxy-1-beta-D-arabino-pentafuranosylcytosine 3'-phosphoric acid, its thymidine ester was prepared via the phosphoramidite method using allyl protection for the phosphate function. This ester is stable under acidic conditions but extremely labile under basic conditions, decomposing with a cleavage of the internucleotide bond even at pH 7.3. 相似文献
113.
We measured cardiac outputs at forty points from five patients by pulse dye densitometry and compared these with those measured by thermodilution method. We obtained a good correlation (y = 1.090 x = . 0.030, n = 40, 5 cases) and small mean bias (0.348 +/- 0.830 l.min-1, n = 40, 5 cases) between the two methods. We suggest that this method of cardiac output measurement by pulse dye densitometry is not invasive and may be more effective than that by thermodilution method. 相似文献
114.
K Kawai H Tagoh K Yoshizaki G Murakami A Muraguchi 《Canadian Metallurgical Quarterly》1996,110(3):288-297
The Pol n component MV, a potent experimental allergen for mice, was purified to homogeneity from extracts of a chironomid distributed worldwide, Polypedium nubifer (PN). The Pol n I component MV was shown to have cross-reactivity to hemoglobins (Hb) derived from all species of chironomids tested. Determination of the amino acid sequence of the first 37 N-terminal residues revealed that it had 30-59% homology to Hb of an European chironomid, Chironomus thummi thummi, which had been known as an important allergen for humans. By Western blot analysis, we showed that sera from asthmatic patients, which had positively reacted to the extract of the adult PN midge, bound to the purified Pol n I component MV. Furthermore, using rabbit polyclonal antibodies raised against synthetic polypeptides corresponding to the N-terminal residues, it was demonstrated that the N-terminal amino acid sequence between position 15 and 35 contained antigenic epitope(s) for human IgE. The results indicate that the Pol n I component MV is an allergen for human beings as well as for mice, and useful as a diagnostic tool for chironomid allergy. 相似文献
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K Uchida H Takeshima K Kikuchi T Shimazui N Miyanaga K Kawai H Akaza A Tsuchiya R Noguchi K Hattori F Manabe K Matsuki R Suzuki S Ishikawa F Kondo T Kobayashi K Koiso 《Canadian Metallurgical Quarterly》1998,25(8):1179-1187
A prospective randomized joint study was conducted to evaluate the usefulness of UFT 1) as a postoperative adjuvant therapy in patients with invasive bladder cancer who had undergone curative combination therapy with operation and/or chemotherapy and/or radiation therapy, 2) as an endocrine chemotherapy in patients with newly diagnosed stage C/D prostate cancer, for a period of 3 years from January, 1992. For bladder cancer, of 36 patients with invasive bladder cancer, clinically cured by combination therapy, 20 patients were treated with UFT as an adjuvant chemotherapy over 12 months, and they were compared to 16 patients with no adjuvant therapy. After excluding 10 inappropriate patients, 12 patients in the UFT treatment group and 14 patients with no adjuvant treatment group were observed. For prostate cancer, of 29 patients with clinically stage C/D prostate cancer, 13 were treated with endocrine therapy in combination with UFT, and 16 patients were treated with endocrine therapy alone. After excluding 7 inappropriate patients, 10 patients with endocrine chemotherapy and 12 patients with hormonal therapy were observed. The non-recurrence rate, survival rate and side effects of UFT were evaluated. In the study of bladder cancer, neither a significant difference of non-recurrent rate nor of survival rate was seen between the two groups. In the study of prostate cancer, neither a significant difference of non-recurrent rate nor of survival rate was seen between the two groups. These findings suggest UFT is less useful as an adjuvant therapy for the invasive bladder cancer and as an endocrine chemotherapy for newly diagnosed advanced prostate cancer. 相似文献
117.
Y Kawai E Tsukamoto Y Nozaki K Kishino T Kohya N Tamaki 《Canadian Metallurgical Quarterly》1998,25(10):1390-1395
PURPOSE: To determine the frequency and nature of intraoperative complications of endocapsular phacoemulsification cataract surgery. SETTING: Dalcross Private Hospital and the Departments of Ophthalmology, Concord Hospital and Prince of Wales Hospital, Sydney, Australia. METHODS: This prospective study included the first 1000 cases of planned endocapsular phacoemulsification cataract surgery performed by an experienced surgeon. A standardized proforma was completed at the time of surgery. Data recorded included pre-existing ocular abnormalities, duration of surgery, nuclear sclerosis grade, and intraoperative complications. RESULTS: Major complications comprised posterior capsule tears with vitreous loss (1.4%), isolated posterior capsule tears (0.7%), and zonulysis (0.1%). Minor complications included anterior capsule tears (3.8%), iris prolapse (0.6%), and ciliary body incision (0.2%). There was a significant trend toward complications as the nuclear sclerosis grade increased. The incidence of major complications was 9.3% in the first 150 cases and 0.9% in the last 850. This represents a relative risk of 9.9 (95% confidence interval 4.2 to 23.0) of a major complication occurring in the first 150 compared with the later 850 cases. CONCLUSION: The frequency of major and minor complications fell sharply after the first 150 operations and was maintained. This study may provide a guide for beginning phacoemulsification surgeons and a basis for experienced surgeons to compare their performance outcomes. 相似文献
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