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211.
T Takeuchi Y Harada K Morishima K Ohta G Satomi S Yasukouchi 《Canadian Metallurgical Quarterly》1998,51(9):723-7; discussion 727-30
We report a 2-month-old boy without any immuno-compromised diseases, who suffered from the severe cytomegalovirus (CMV) infection after the subclavian flap aortoplasty and pulmonary artery banding for coarctation complex. He underwent the operation at 2 months old and received 2 units of irradiated packed red blood cells before and after the surgery. His postoperative course was uneventful but the interstitial pneumonitis, until he developed watery diarrhea 10 days after the surgery following hepatitis with the marked hepatomegaly 3 weeks after. Since CMV infection was confirmed as the cause of the pneumonitis, enterocolitis and hepatitis, he was initially treated by gamma-globulin with the high CMV titer at a dose of 200 mg/kg/day for 2 days and ganciclovir at a dose of 10 mg/kg/day for 14 days. Because of the persistent CMV infection, he needed two more treatments of ganciclovir at the same dosage and gamma-globulin once a week for 2 months. He finally recovered from severe CMV infection 5 months after the above treatments. In conclusion, the severe CMV infection can occur by blood transfusion even in the surgical case with normal immune system. If one finds pneumonitis, hepatitis or enterocolitis after any type of surgery with history of blood transfusion, CMV infection should be suspected as the cause of these diseases. 相似文献
212.
M Yoshiyama S Kim H Yamagishi T Omura T Tani M Takagi I Toda M Teragaki K Akioka K Takeuchi 《Canadian Metallurgical Quarterly》1994,58(5):362-368
Angiotensin II is well known to have a cardiotoxic effects. However, it is still unclear whether exogenous angiotensin I or angiotensin II has a deleterious effect on myocardial ischemia-reperfusion injury. To examine this deleterious effects, we administered angiotensin I and angiotensin II to perfused hearts before ischemia, and measured creatine kinase (CK) release and cardiac function during subsequent reperfusion. Wistar Kyoto rats were used and the hearts were perfused by the Langendorff technique at a constant flow (10 ml/min). Seven hearts were perfused for 20 min and then subjected to 15 min of global ischemia (Control). In the experimental groups, during the 5 min before ischemia, we administered 100 ng/ml angiotensin I (Ang I; n = 9), 1 microgram/ml enalaprilat (ACEI; n = 5), both agents (ACEI + Ang I) (n = 6), or 10 ng/ml angiotensin II (Ang II; n = 6). The perfusates were then sampled to measure angiotensin II. After 15 min of ischemia, the hearts were reperfused with control perfusate. Throughout the 20 min of reperfusion, the effluent was collected to measure cumulative CK release. Angiotensin I increased coronary perfusion pressure (CPP) by 32 +/- 4 mmHg, however, the angiotension converting enzyme inhibitor inhibited the increase of CPP by angiotension I (11 +/- 1 mmHg) (p < 0.01). The contents of angiotensin II in the effluent in Ang I and Ang I + ACEI were 11.5 +/- 1.9 ng/ml and 4.0 +/- 0.5 ng/ml (p < 0.01). After 20 min of reperfusion, the left ventricular developed pressure was unchanged in all of the groups. CPP was also unchanged by ischemia in all of the groups.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
213.
In order to elucidate the copolymerization mechanism, the properties of the copolymer obtained by the iodine-initiated copolymerization of the tetraoxane–1,3-dioxolane–methylal system have been studied using gas chromatography, microscopy, scanning electron microscopy, differential scanning calorimetry, and gel permeation chromatography. From the behavior of the thermal stability and gas chromatography of the reaction mixture, it was found that reactivity of 1,3-dioxolane with active center is larger than that of tetraoxane, i.e., more than 90% 1,3-dioxolane is consumed at an early stage of the polymerization. The results obtained by microscopy, DSC, and GPC of the copolymer suggested that the copolymerization proceeds from the surface to the center of the tetraoxane crystal as if it were a core model. It was also suggested that the heterogeniety in copolymer properties can be explained not only by heterogeneous dispersion of 1,3-dioxolane in tetraoxane crystal, but also by the difference of reactivity of 1,3-dioxolane with the active center. 相似文献
214.
We investigated the role of endogenous prostaglandins in the inhibitory effect of exogenous secretin and the antiulcer agent plaunotol on gastric acid secretion in the rat. Intravenous infusion of secretin (0.05 CU/kg/h) and intraduodenal administration of the secretin-releasing agent, plaunotol (320 mg/h), resulted in significant inhibition of gastric acid secretion stimulated by intravenous infusion of pentagastrin (0.3 micrograms/kg/h), and this was accompanied by an increase in the prostaglandin E2 content of the gastric mucosa. Intraduodenal administration of plaunotol (320 mg/h) produced plasma secretin levels comparable to the levels achieved by intravenous infusion of secretin (0.05 CU/kg/h). Intravenous administration of prostaglandin synthesis inhibitor, indomethacin (2 mg/kg + 1 mg/kg/h), completely abolished both the inhibitory action of secretin and plaunotol on gastric acid secretion, and the increase in gastric mucosa prostaglandin E2 induced by secretin and plaunotol. The results indicate that endogenous prostaglandins play a significant role in the inhibitory action of exogenous and plaunotol-released endogenous secretin in the rat. 相似文献
215.
216.
Tada M. Tamura T. Ito F. Ohtake H. Narihiro M. Tagami M. Ueki M. Hijioka K. Abe M. Inoue N. Takeuchi T. Saito S. Onodera T. Furutake N. Arai K. Sekine M. Suzuki M. Hayashi Y. 《Electron Devices, IEEE Transactions on》2006,53(5):1169-1179
Robust porous low-k/Cu interconnects have been developed for 65-nm-node ultralarge-scale integrations (ULSIs) with 180-nm/200-nm pitched lines and 100-nm diameter vias in a single damascene architecture. A porous plasma-enhanced chemical vapor deposition (PECVD)-SiOCH film (k=2.6) with subnanometer pores is introduced into the intermetal dielectrics on the interlayer dielectrics of a rigid PECVD-SiOCH film (k=2.9). This porous-on-rigid hybrid SiOCH structure achieves a 35% reduction in interline capacitance per grid in the 65-nm-node interconnect compared to that in a 90-nm-node interconnect with a fully rigid SiOCH. A via resistance of 9.7 /spl Omega/ was obtained in 100-nm diameter vias. Interconnect reliability, such as electromigration, and stress-induced voiding were retained with interface modification technologies. One of the key breakthroughs was a special liner technique to maintain dielectric reliability between the narrow-pitched lines. The porous surface on the trench-etched sidewall was covered with an ultrathin plasma-polymerized benzocyclobuten liner (k=2.7), thus enhancing interline time-dependent dielectric breakdown reliability. The introduction of a porous material and the control of the sidewall are essential for 65-nm-node and beyond scaled-down ULSIs to ensure high levels of reliability. 相似文献
217.
An experimental 1.5-V 64-Mb DRAM 总被引:1,自引:0,他引:1
Nakagome Y. Tanaka H. Takeuchi K. Kume E. Watanabe Y. Kaga T. Kawamoto Y. Murai F. Izawa R. Hisamoto D. Kisu T. Nishida T. Takeda E. Itoh K. 《Solid-State Circuits, IEEE Journal of》1991,26(4):465-472
Low-voltage circuit technologies for higher-density dynamic RAMs (DRAMs) and their application to an experimental 64-Mb DRAM with a 1.5-V internal operating voltage are presented. A complementary current sensing scheme is proposed to reduce data transmission delay. A speed improvement of 20 ns was achieved when utilizing a 1.5-V power supply. An accurate and speed-enhanced half-V CC voltage generator with a current-mirror amplifier and tri-state buffer is proposed. With it, a response time reduction of about 1.5 decades was realized. A word-line driver with a charge-pump circuit was developed to achieve a high boost ratio. A ratio of about 1.8 was obtained from a power supply voltage as low as 1.0 V. A 1.28 μm2 crown-shaped stacked-capacitor (CROWN) cell was also made to ensure a sufficient storage charge and to minimize data-line interference noise. An experimental 1.5 V 64 Mb DRAM was designed and fabricated with these technologies and 0.3 μm electron-beam lithography. A typical access time of 70 ns was obtained, and a further reduction of 50 ns is expected based on simulation results. Thus, a high-speed performance, comparable to that of 16-Mb DRAMs, can be achieved with a typical power dissipation of 44 mW, one tenth that of 16-Mb DRAMs. This indicates that a low-voltage battery operation is a promising target for future DRAMs 相似文献
218.
The shrinkage rate of liquid CO2 droplets in water at 3°C was measured by the use of high-pressure vessel placed in a constant-temperature room. The change of the diameter of the droplet was observed at pressures of 28 MPa and 35 MPa using a time-lapse video camera. Bromocresol green was employed as a pH indicator, and was effective in monitoring the profile of carbonic acid distribution. When a droplet of liquid CO2 was injected, CO2 hydrate immediately formed and covered the surface of the droplet. The diameter of the liquid CO2 droplet reduced gradually at a rate of 5.0 × 10?7 m/s. It is predicted, from the viewpoint of ocean CO2 sequestration, that a thin film of hydrate will form at the interface of sea water and liquid CO2, and that the hydrate film will greatly control the dissolution of CO2 into sea water. 相似文献
219.
Association of TAP1 and TAP2 with systemic sclerosis in Japanese 总被引:1,自引:0,他引:1
F Takeuchi S Kuwata K Nakano H Nabeta GH Hong Y Shibata K Tanimoto K Ito 《Canadian Metallurgical Quarterly》1996,14(5):513-521
Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired clonal stem cell disorder resulting in insufficient and defective haematopoesis associated frequently with aplastic anaemia (AA). A deficiency of the glycosyl phosphatidylinositol (GPI)-anchored complement activation regulatory proteins CD55 and CD59 is responsible for an increased sensitivity of erythrocytes to complement attack leading to chronic intravascular haemolysis with haemoglobinuria. In this study we investigated the effects of complement activation caused by anti-thymocyte globulin (ATG) treatment on the PNH clone in a patient affected with the PNH/AA-syndrome. Fluid phase complement components C3, C4, C6 and terminal complement complex (TCC) were assayed by ELISA. CD55, CD59 and cell-associated TCC were monitored by flow cytometry. ATG treatment resulted in profound systemic complement activation which led to a decrease in the levels of native C3 and C4 to 65% and 40%, respectively, of the original levels on day 5 and of C6 and TCC to 61% and 23%, respectively, on day 10. A return to pre-treatment levels was observed for C3 by day 15, for C6 by day 30 and for C4 by day 90. Flow cytometry revealed that the deficiency in the GPI-anchored protein was restricted to granulocytes, while lymphocytes remained unaffected. Cell-bound TCC increased by 1.67-fold and 2.37-fold on day 5 and day 10, respectively, decreasing to 1.40-fold and 1.30-fold on day 15 and day 30, respectively. The percentage of PNH granulocytes as identified by the absence of the CD55- and CD59-antigens exhibited a temporary decrease from 72% on day 0 to 65% on day 5 and 59% on day 10 and returned thereafter to the original percentage of 70% by day 15 and exceeding this level to 76% on day 30 and 79% on day 90. We report profound activation of the classical pathway of the complement cascade and the terminal complement complex by the globulin leading to a transient decrease of the PNH clone, presumably due to subsequent lysis of the PNH cells devoid of complement regulatory proteins. 相似文献
220.
We propose a novel quantum-well (QW) structure for GaInNAs-GaAs lasers that can emit 1.3 μm or longer wavelength light. The idea is insertion of lattice-matched GaInNAs intermediate layers between well and barrier, which is effective for elongating the emission wavelength and reducing well thickness. It is shown that 1.3-μm emission is achievable by using the proposed GaInNAs-GaAs QW with a well thickness thinner than that of conventional rectangular GaInNAs QWs. This structure will relax the design limitation of strained GaInNAs layers 相似文献