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22.
Manabu Muto Mitsuhiro Fujishiro Yoshitaka Sato Yasumasa Niwa Mitsuru Kaise Mototsugu Kato Kaiyo Takubo 《Digestive endoscopy》2007,19(Z1):S153-S155
Optical technological innovations enable us to visualize cellular nuclei endoscopically. Herein is described a protocol design for a multicenter study for the ex vivo evaluation of endocytoscopy. The present study was performed by the Endoscopy Forum Japan study group. 相似文献
23.
24.
S Sato Y Watanabe K Okamura R Hamanaka T Mori K Kohno M Kuwano 《Anti-cancer drug design》1989,4(2):125-135
Ethyl 6-p-5-(l-imidazolyl) pentyloxyphenoxy-2, 2-dimethylhexanoate hydrochloride (YM534) is a new synthetic anti-tumor compound. Combinations of YM534 with other anti-cancer agents were examined to ascertain whether YM534 potentiated other anti-cancer agents against the KB cell line and its multidrug-resistant counterpart, VJ-300. YM534 potentiated the cytotoxic action of vincristine and actinomycin D about 2-fold against KB cells, but not those of daunomycin and adriamycin. By contrast, YM534 only slightly reversed drug-resistance to adriamycin and daunomycin in VJ-300 while it reversed 5-fold vincristine resistance and 60-fold actinomycin D resistance in VJ-300. The reversal effect of YM534 on actinomycin D and vincristine-resistance in VJ-300 cells appeared to be due to enhanced accumulation of [3H] actinomycin D and [3H] vincristine in VJ-300 cells by YM534. YM534 inhibited efflux of actinomycin D and vincristine from VJ-300 cells, and it also enhanced cellular uptake of these anti-cancer agents. YM534 enhanced cellular accumulation of both actinomycin D and vincristine in the sensitive KB cells. YM534 is thus a unique anti-cancer agent since combinations of other anti-cancer agents with YM534 are expected to augment anti-tumor activity of them. By contrast, YM212, a carboxy analog of YM534, had much less activity to potentiate vincristine and actinomycin D). YM534 at 100-1000 microM almost completely inhibited the photoaffinity labeling of [3H] azidopine to the 170-kD P-glycoprotein of VJ-300 cell membranes, but YM212 showed much less inhibitory action on the photoaffinity labeling. YM534 could also inhibit the photoaffinity labeling of deglycosylated P-glycoprotein. 相似文献
25.
H Iioka I Moriyama K Itoh K Hino Y Okamura Y Itani Y Katoh M Ichijo 《Nippon Sanka Fujinka Gakkai zasshi》1987,39(12):2133-2136
To elucidate the role of glutathione (GSH) on placental amino acid transport, we investigated L-lysine transport using microvillous membrane vesicles prepared from full term human placenta. 1. The transport of L-lysine into microvillous membrane vesicles was not affected by glutathione. 2. The transport of L-lysine into microvillous membrane vesicles was inhibited by inorganic mercury (Hg2+), and 0.1mM Hg2+ inhibited 34% of this transport and 1mM Hg2+ inhibited 50%. 3. The transport of L-lysine inhibited by Hg2+ was almost completely restored when glutathione was added simultaneously. These results indicated that glutathione defended the inhibitory action of inorganic mercury on L-lysine transport across microvillous membrane. 相似文献
26.
Growth fractions of transitional cell carcinomas of the bladder defined by the monoclonal antibody Ki-67 总被引:4,自引:0,他引:4
We used an immunohistochemical technique with the monoclonal antibody Ki-67, which recognizes nuclear antigen expressed in proliferating cells to determine the growth fractions of 5 normal mucosa specimens and 55 transitional cell carcinomas of the bladder. Normal mucosa had a mean value of 0.37 +/- 0.35% cells positive for Ki-67, whereas 9 histological grade 1 tumors showed 2.2 +/- 1.5%, 31 grade 2 tumors averaged 10.1 +/- 7.5% and 15 grade 3 tumors yielded 19.5 +/- 9.0%. These values were significantly different from each other (p less than 0.01), with Ki-67 indexes for grade 2 varying from 0.3 to 24.6%. Nonpapillary tumors had significantly higher indexes than papillary tumors (20.1 +/- 8.0 versus 6.7 +/- 5.9, p less than 0.01). The Ki-67 indexes were 4.6 +/- 4.5% for stage Ta (20 cases), 7.8 +/- 4.7% for stage T1 (14) and 20.2 +/- 7.8% for stages equal to or higher than T2 (21). Significant differences were noted between stages Ta and T1 (p less than 0.05) and between stages T1 and T2 or greater (p less than 0.01). Tumors with muscle layer invasion often showed more than 15% Ki-67 positive cells. Our results imply that Ki-67 indexes not only provide objective information to determine a malignant potential but also help to select the treatment. 相似文献
27.
Intraperitoneal high-dose cisplatinum chemotherapy (CDDP-ip) in patients with carcinomatous peritonitis 总被引:1,自引:0,他引:1
T Noda M Oku Y Kiyozuka Y Ninomiya K Hino Y Okamura M Maruyama M Ichijo 《Gan to kagaku ryoho. Cancer & chemotherapy》1987,14(4):1025-1032
Immediately after CDDP-ip, the level of free Pt in ascites reached nearly 100 micrograms/ml, and the AUC (area under the curve) for ascites was 20-140 times greater than that for serum. The free Pt in serum following CDDP-ip administration was detected for several hours, and interestingly, the AUC for serum after ip therapy was 0.4-2.2 times greater than that after iv therapy. As a result, free Pt was found to act on cancer cells in the abdominal cavity directly at a high concentration. At the same time, the possibility of an antitumor effect from the vascular side of the tumor was also suggested. On the other hand, cases of ovarian cancer had various levels of peritoneal clearance (CLp), which depended on the severity of their carcinomatous peritonitis. The CLp had a great influence on the peak plasma concentration and on the AUC of free Pt in serum. In particular, the peak plasma concentration produced by CDDP-ip was 40-80% of the plasma concentration produced by CDDP-iv. These findings indicate that high-dose CDDP-ip is possibly effective and useful for advanced ovarian cancer, producing only very mild side effects. 相似文献
28.
Yoshitaka Hibino Ken-ichiro Hata Kunio Horie Shuhei Torii Minoru Ueda 《Journal of cranio-maxillo-facial surgery》1996,24(6):346-351
Numerous clinical reports have shown the utility of cultured epithelial grafting in the field of plastic and reconstructive surgery. Recently, freezing storage of the cultured epithelium has been tried and has successfully grafted after thawing. It is clinically convenient if it is possible for cultured epithelium to keep its normal structure and viability. However, few papers have described the structural changes in cultured epithelium after freezing storage. In the present study, the morphological changes and cell viability of cultured mucosal epithelial sheets after freezing were studied in comparison with cultured epidermal sheets. Furthermore, we discuss the effect of storage temperature and cryoprotectants.As a result, there were some structural changes such as vacuolar degeneration in the cultured mucosal sheets using dimethyl sulphoxide (DMSO) as a cryoprotectant. Such changes were more clearly observed at −80°C than at −196°C with DMSO. However, little morphological change was observed in both epithelial sheets cultured with glycerin. The cell viability analysed by flow cytometry showed that more than 62% of the cells kept their viability after freezing storage. These results suggest that the optimum conditions of freezing for cultured epithelium were −196°C storage by slow cooling methods with glycerin as a cryoprotectant. 相似文献
29.
Yoshitaka Hayashi Shigeaki Ohtake Yoshiki Sawa Hiroshi Imagawa Nobuaki Hirata Hikaru Matsuda 《General thoracic and cardiovascular surgery》1998,46(8):724-729
A 68-year-old man, who had underwent aortic valve replacement (AVR) with Björk-Shiley disc valve for aortic regurgitation 17 years ago, was transferred to our hospital complaining of facial ruddiness and swelling, without chest or back pain. Preoperative examination revealed DeBakey type II aortic dissection, which caused superior vena cava syndrome (SVC syndrome). Emergent ascending aortic replacement was performed, postoperatively central venous pressure (CVP) decreased from 33 to 9 mmHg, and SVC syndrome was relieved. Painless aortic dissection after AVR, presenting as SVC syndrome, is a rare case, and close follow-up should be performed under consideration of painless aortic dissection late after AVR. 相似文献
30.
The distribution patterns of choline acetyltransferase (CAT), as a marker for cholinergic neurons, and Calbindin-D28k (CaBP) immunoreactivities in the forebrain basal ganglia of the Japanese monkeyMacaca fuscata were compared. Similar distribution patterns of CAT and CaBP immunoreactivities were found in the medial septal nucleus (MS) and the nucleus of the diagonal band of Broca (DBB). Double-labeling fluorescence immunocytochemistry revealed that most, but not all, cholinergic neurons were CaBP-immunoreactive in the MS and DBB. The results suggest that CaBP may play a role in the septohippocampal cholinergic neuron system of the monkey. 相似文献