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T Yano Y Fukuyama H Yokoyama S Kuninaka Y Terazaki T Uehara H Asoh Y Ichinose 《Canadian Metallurgical Quarterly》1998,14(2):152-155
OBJECTIVE: To determine the distribution and significance of microcalcifications in histologic sections of the prostate. DESIGN: Retrospective review of all histologic slides of completely embedded prostates from surgical specimens. MATERIALS: Randomly selected material included 266 radical prostatectomy and 10 cystoprostatectomy prostates without prostate cancer. Nonrandomly selected specimens included 26 radical prostatectomy specimens with a Gleason pattern 5 component, 24 cases with collagenous micronodules, and 8 cases previously noted to have microcalcifications within foci of prostate cancer. RESULTS: Four patterns of microcalcifications were noted in association with prostate cancer: (1) dystrophic calcification in the comedo-type necrosis of Gleason pattern 5, (2) intraluminal calcification in cribriform-type Gleason pattern 3 prostate cancer, (3) intraluminal calcification in small acinar adenocarcinoma, and (4) stromal calcification within collagenous micronodules associated with prostate cancer. Microcalcifications were noted in 32% of prostates without cancer; 1.9% of randomly selected prostates demonstrated microcalcifications associated with prostate cancer. CONCLUSIONS: Microcalcifications are less common in association with prostate cancer than with benign prostatic ducts and acini. However, intraluminal microcalcifications associated with an atypical small glandular proliferation should not be taken as unequivocal evidence of a benign process. 相似文献
43.
Kokubun Y. Suzuki S. Fuse T. Uehara H. Iga K. Oikawa M. Misawa S. 《Electronics letters》1983,19(24):1009-1010
A novel mode scrambler for multimode optical waveguides is proposed to stabilise branching characteristics against the mode excitation conditio. A 2 × 2 optical star coupler is fabricated using this mode scrambler, and a stable branching ratio is realised with an excess insertion loss of 2.7 dB. 相似文献
44.
An imaging array consisting of five Yagi-Uda antennas in a dielectric has been constructed for 50 GHz that has antenna patterns suitable for millimetre-wave applications. Crosstalk levels of less than -30 dB between adjacent antennas in an f/1.0 imaging array have been measured in 5 GHz model experiments.<> 相似文献
45.
M Tatsuta H Iishi M Baba H Yano H Uehara A Nakaizumi 《Canadian Metallurgical Quarterly》1996,17(2):293-296
The effects of baclofen, a gamma-amino-n-butyric acid receptor B agonist, on gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine and how its effects are influenced by selective (M1) and non-selective (M1 and M2) pharmacological blockade of muscarinic receptors were investigated in inbred Wistar rats. Rats were given s.c. injections of 8 mg/kg body wt baclofen with and without 0.5 mg/kg body wt atropine (non-selective M1 and M2 muscarinic receptor antagonist) or 1.0 mg/kg body wt pirenzepine (selective M1 muscarinic receptor antagonist) every other day after a 25 week carcinogen treatment. At week 52 baclofen significantly decreased the incidence of gastric cancers. Concomitant treatment with atropine significantly attenuated the inhibition by baclofen of gastric carcinogenesis, but combined use with pirenzepine had no significant effect on the inhibition by baclofen of gastric carcinogenesis. Baclofen also significantly decreased the labeling index of the antral mucosa. Baclofen plus atropine attenuated the decrease in the labeling index of the antral mucosa due to baclofen, but baclofen plus pirenzepine had no significant effect on the labeling index. These results suggest that the inhibition of gastric carcinogenesis by baclofen is mediated through muscarinic receptors and M2 receptors, but not M1 receptors, are involved in this response. 相似文献
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In order to investigate the optimum transmission bit-rate for teletext signals in the 525-line television system, laboratory and field tests were carried out using binary NRZ digital data signals of several bit-rates to 5.73 Mbit/s ( 364fH, 8/5fsc). In these tests, the bit-errors and eye-openings of PN signals were measured and subjective evaluation of teletext signals was also made under various receiving conditions. The results have indicated that a digital data signal of 5.73 Mbit/s could be utilized for teletext in the 525-line television system. The Japanese teletext system now being developed employs this bit-rate for transmitting and displaying the signals. 相似文献
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Mamoru Ishida Takeo Uehara Toshio Arai Hideki Takeda Tadashi Yamaguchi Takeshi Taniguchi Tetsuya Katsumi Masayuki Kobayashi Hitoshi Ofune 《Intermetallics》2002,10(11-12)
The performance of MU/SC conversion sleeve produced by bulk metallic glass (Zr55Al10Ni5Cu30) was examined. A precision die-casting method was applied to improve size accuracy. The size accuracy of the conversion sleeve produced by the precision die-casting method was ±1 μm, and optical insertion loss (Li) was less than 0.3 dB for a standard value. The wear resistance of metallic glass is improved by surface oxidation treatment in air at 673 K. The MU/SC conversion sleeve produced from bulk metallic glass has superior characteristics for optical parts. 相似文献