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931.
H Masuda T Yamada H Nagamatsu K Nagahama S Kawakami T Watanabe T Negishi T Morita 《Canadian Metallurgical Quarterly》1997,88(1):40-45
PURPOSE: To describe the late onset of sequential multifocal bleb leaks as a postoperative complication after filtering surgery with antimetabolites. MATERIALS: Retrospectively, 385 consecutive eyes (304 patients) undergoing trabeculectomy with 5-flurouracil (5-FU) or mitomycin C (MMC) from 1989 to 1994 were reviewed. Eyes with filtration bleb leak occurring 6 months or more after trabeculectomy were analyzed, and clinical characteristics of the filtration bleb, response to treatment, and bleb histopathology from eyes undergoing bleb excision were analyzed. RESULTS: In seven (1.8%) of 385 consecutive eyes from 304 patients undergoing glaucoma filtration surgery with 5-FU or MMC, repetitive bleb leaks in different locations of the bleb were observed from 9 to 44 months (mean, 20.4 months) after the procedure. One hundred ninety-three eyes (50%) were treated with 5-FU and the remaining eyes, with MMC. All eyes had transparent, avascular, lobular, cystic blebs. Bleb leaks occurred in five eyes treated postoperatively with subconjunctival 5-FU and in two eyes in which MMC was used intraoperatively. Three eyes (all treated with 5-FU) required surgical excision, and four eyes healed with soft contact lens, cyanoacrylate glue, or intrableb injection of autologous blood. Histopathology of the bleb leak sites demonstrated focal epithelial thinning and interruption with subjacent hypocellularity and stromal collagen degeneration. CONCLUSION: Late sequential multifocal bleb leaks may occur after glaucoma filtration surgery with administration of antimetabolites (5-FU or MMC) and are associated with epithelial break-down, hypocellularity, and stromal collagen necrosis in the filtration bleb. 相似文献
932.
Ultra-wide-band tellurite-based fiber Raman amplifier 总被引:2,自引:0,他引:2
We describe the first wide-band tellurite-based fiber Raman amplifier (T-FRA) for application to seamless ultra-large-capacity dense wavelength-division multiplexing (WDM) systems. First, we confirmed that the Raman scattering characteristics of the tellurite-based fiber has so large a gain coefficient and Stokes shift that we can achieve a wide-band tellurite-based fiber Raman amplifier with a shorter fiber length than when using silica-based fiber. Second, we investigated the small signal gain and the signal transmission characteristics for a high gain and high output power operation with a single-stage amplifier. Focusing on double Rayleigh scattering, we compared the high gain limit of tellurite- and silica-based fibers. We then studied the impact of nonlinear effects by measuring the bit error rate (BER) when using a two-stage amplifier with a high output power of 18.8 dBm in which we simultaneously amplified eight channel signals in the L-band located on the ITU 100-GHz grid. Finally, we designed a wide-band tellurite-based fiber Raman amplifier with a multiwavelength band pumping scheme. We constructed this amplifier with a tellurite-based fiber only 250 m in length pumped by four-wavelength-channel laser diodes, and it provided a 160-nm bandwidth with a gain of over 10 dB and a noise figure below 10 dB from 1490 to 1650 nm. We also measured the BER to confirm the transmission characteristics of the amplifier for single channel operation over the whole signal wavelength range of 160 nm. We thus confirmed that the amplifier could be employed in ultra-high-capacity WDM systems. 相似文献
933.
N Hattori N Tamaki T Kudoh I Masuda Y Magata H Kitano M Inubushi E Tadamura K Nakao J Konishi 《Canadian Metallurgical Quarterly》1998,39(11):1835-1840
The purpose of this study was to evaluate oxidative metabolism and its response by dobutamine in patients with noninsulin-dependent diabetes mellitus (NIDDM) using 11C-acetate PET. METHODS: We studied 16 patients with NIDDM (9 men, 7 women; mean age 53.7 +/- 12.8 yr) and 6 healthy male control subjects (mean age 41.8 +/- 17.2 yr). None of them had an abnormality on stress-perfusion SPECT. The 11C-acetate clearances (Kmono) were compared regionally for five myocardial segments in all subjects at rest and during low-dose dobutamine stress in 13 patients (8 patients with NIDDM, age 51.9 +/- 13.6 yr; 5 healthy male control subjects, age 45.6 +/- 16.3 yr). Correlation between regional Kmono and rate-pressure product (RPP) was also studied. RESULTS: At rest, the clearance of 11C-acetate was slightly heterogeneous for both patients with NIDDM and healthy control subjects, with smaller values in the apex and inferior wall in both groups. The difference became significant during dobutamine stress in the patients. The RPP-to-Kmono (average for five segments) ratio at rest was slightly smaller in the patients (1042.7 +/- 559.1 x 0.01) than in the healthy control subjects (1391.4 +/- 209.6 x 0.01, not significant), and those during dobutamine stress were almost the same in the two groups (1457.3 +/- 737.4 x 0.01 and 1486.0 +/- 211.8 x 0.01, respectively). A significant correlation was seen between regional Kmono and RPP in every segment in the healthy control subjects (average; r = 0.89; p < 0.01), whereas more scattered correlation with greater regional variation was observed in the patients (average; r = 0.31; p value was not significant). CONCLUSION: Patients with NIDDM showed slight regional heterogeneity in myocardial oxidative metabolism. They also had more scattered correlation between myocardial oxidative metabolism and cardiac work (RPP) than healthy control subjects, with the smallest correlation coefficient observed in the inferior wall. These findings may help the understanding of dynamics in myocardial oxidative metabolism of NIDDM hearts. 相似文献
934.
EM Masuda DM Kessler RL Kistner B Eklof DT Sato 《Canadian Metallurgical Quarterly》1998,28(1):67-73; discussion 73-4
PURPOSE: Although the fact is well accepted that deep venous thrombosis (DVT) of the iliac, femoral, and popliteal veins can lead to the post-thrombotic (postphlebitic) syndrome, the significance of isolated calf DVT on the development of late venous sequelae and physiologic calf dysfunction is unknown. The purpose of this study was to review the outcome of 58 limbs with isolated calf DVT and report the clinical, physiologic, and imaging results up to 6 years after the onset of DVT. METHODS: The study consisted of 58 limbs of 54 patients in whom isolated calf vein DVT was diagnosed between 1990 and 1995. Proximal propagation of clot, lysis of thrombi, and development of symptomatic pulmonary emboli were examined. Of the patients, 28 received anticoagulation therapy, and 26 did not, but they had follow-up with serial duplex scans. At late follow-up 1 to 6 years later (median, 3 years), 23 patients were examined for the post-thrombotic syndrome, and all 23 underwent clinical examination, color-flow duplex scanning, and air plethysmography. RESULTS: Proximal propagation of DVT from the calf veins into the popliteal or thigh veins occurred in 2 of 49 cases (4%) within 2 weeks of diagnosis. No patient had clinically overt pulmonary emboli develop regardless of whether anticoagulation therapy was received or not. The most common site for calf DVT was the peroneal vein (71%). Complete lysis of calf thrombi was found in 88% of the cases by 3 months. At 3 years, 95% of the patients were either asymptomatic or mildly symptomatic, and 5% had discoloration of the limb. No ulcers occurred. By air plethysmography, physiologic abnormalities were found in 27% of the cases, which was not significantly different from normal controls. Valvular reflux by duplex scanning of the calf vein segment with DVT was found in 2 of 23 cases (9%). However, reflux in at least one venous segment not involved with DVT was found in 7 of 23 cases (30%), which was higher than, but not statistically different from, normal controls, with reflux occurring in 5 of 26 cases (19%). CONCLUSIONS: Isolated calf vein DVT leads to few early complications (ie, clot propagation, pulmonary emboli) and few adverse sequelae at 3 years. The peroneal vein is most commonly involved and should be a part of the routine screening for DVT. Lysis of clot usually occurs by 3 months. Although valvular reflux rarely is found in the affected calf vein at 3 years, reflux may be found in adjacent uninvolved veins in approximately 30% of the cases. The question of whether this will lead to future sequelae, such as ulceration, will require longer follow-up. 相似文献
935.
936.
Yasuhisa Sonobe Hiroshi Fukuyama Tadashi Okamoto Nagahide Kani Kouzou Kimura Katsumi Kobayashi Yoshihiro Masuda Yasuhiro Matsuzaki Shigeru Mochizuki Tomoya Nagasaka Akiyuki Shimizu Hiroyuki Tanano Masaharu Tanigaki Masaomi Teshigawara 《Canadian Metallurgical Quarterly》1997,1(3):90-115
The “Design Guidelines of FRP Reinforced Concrete Building Structures” was established in 1993 as one of the final outputs of the research committee on fiber-reinforced plastic (FRP) reinforced concrete building structures organized under the Japanese Ministry of Construction's research and development project titled: “Effective Use of Advanced Construction Materials (1988–92).” These Guidelines are a translation of the Japanese guidelines. They describe the design concept for nonprestressed concrete structures reinforced with FRP rebars, and the calculation equations are all relegated to the commentaries due to lack of design data on FRP reinforced concrete structures. A limit-state design method has been adopted under the guidelines. Among the subjects covered are overview, design method, materials, loads and combination, stress and deformation, ultimate state design, serviceability state design, structural requirement, and testing methods for the tensile strength and bond strength of materials. “The Design Guidelines for FRP Prestressed Concrete Members” is separate from these guidelines. 相似文献
937.
S Matsumoto K Hasuo A Mizushima F Mihara M Fukui T Shirouzu K Masuda 《Canadian Metallurgical Quarterly》1998,19(6):1163-1165
Two cases of intracranial penetration of a plastic or wooden chopstick via the optic canal are described. CT scans showed the chopsticks as linear hypodense structures in the suprasellar cistern contiguous with the optic canal. In one case, MR imaging was performed, which clearly depicted the foreign body and adjacent brain structures. Although they are extremely rare, transorbital intracranial penetrating injuries via the optic canal require physicians' awareness. 相似文献
938.
Oda T. Yamashita R. Haga I. Takahashi T. Masuda S. 《Industry Applications, IEEE Transactions on》1996,32(1):118-124
The decomposition performance of the surface induced plasma chemical processing (SPCP) for chlorofluorocarbon (83 ppm CFC-113 in air), acetone, trichloroethylene, and isopropylalcohol was experimentally examined. In every case, very high decomposition performance, more than 90 or 99% removal rate, is realized when the residence time is about 1 second and the input electric power for a 16 cm3 reactor is about 10 W. Acetone is the most stable compound and alcohol is most easily decomposed. The decomposed product-analysis by a gaschromato-massspectrometer has just started but very poor results are obtained. In fact, some portion of the isopropylalcohol may change to acetone which is worse than alcohol. The necessary energy to decompose one mol gas diluted in the air is calculated from the experiments. The necessary energy level for acetone and trichloroethylene is about one-tenth or one-fiftieth of that for chlorofluorocarbon 相似文献
939.
Matsunaga N. Yamamoto M. Hatta Y. Masuda H. 《Electron Devices, IEEE Transactions on》2003,50(5):1194-1199
This paper describes an improved device model of GaAs MESFETs and heterojunction FETs for the design and analysis of analog integrated circuits. The proposed device model provides a new expression for the current and the capacitance of the device,which gives excellent agreements with experimental data for all regions of device operation. For the expression of the low frequency anomalies of GaAs devices, an improved technique with an equivalent circuit are presented to model the frequency dispersion of the transconductance and the drain conductance of the device, which give a good agreement with the experimental data of both the frequency dispersion and the lag effect of the device. The new device model proposed here clearly provides a superior prediction of the performance of GaAs analog integrated circuit. 相似文献
940.
T Katakura T Masuda T Ikeda S Abe T Shimada S Shibuki S Ohara S Asaki T Toyota 《Canadian Metallurgical Quarterly》1998,95(9):992-1000
In this study, we performed immunohistochemical studies using p53 and Ki-67 immunostaining in 48 depressed type adenomas, and compared with protruded type adenomas (n = 28) and depressed type well differentiated mucosal gastric cancers (mcancer: n = 46). Focal and diffuse p53 staining patterns were not noticed in depressed type adenomas and in protruded type adenomas, but were noticed in mcancers (focal: 4.3%, diffuse: 41.3%). Ki-67 positive cells were noticed in surface epithelium in 24.4% of depressed type adenomas, in 21.4% of protruded type adenomas and in 87.0% of mcancers. Ki-67 positive rate in foveolar epithelium (superior, middle, inferior) were noticed in (31.1%, 12.9%, 6.1%) of depressed type adenomas, in (33.4%, 15.4%, 6.9%) of protruded type adenomas and in (33.4%, 31.4%, 20.4%) of mcancers. These results suggest that from the point of immunohistochemistry, depressed type adenomas were similar to protruded type adenomas, but were different from mcancers. 相似文献