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排序方式: 共有675条查询结果,搜索用时 15 毫秒
61.
K Kataoka M Taneda F Akai S Akizuki K Matsushita A Kinoshita 《Canadian Metallurgical Quarterly》1996,39(2):38-40
We experienced that therapeutic embolization of a large cerebral arteriovenous malformation (AVM) led to venous outflow obstruction resulting in intracranial hypertension in a patient who had undergone external decompression. To evaluate hemodynamic changes after embolization, we monitored the cerebrospinal fluid pressure in the next four patients who underwent endovascular treatment. The embolization of a medium AVM resulted in a slight increase in the cerebrospinal fluid pressure. In two medium AVMs, embolization produced slight decreases in the cerebrospinal fluid pressure. In a small AVM, we did not observe any changes in the cerebrospinal fluid pressure during the endovascular treatment. We discuss the mechanism of changes in the intracranial pressure after embolization and conclude that monitoring of the cerebrospinal fluid pressure immediately yields useful information for hemodynamic changes during endovascular treatment. 相似文献
62.
Brains from 21 patients with Alzheimer's disease (AD), nine with diffuse Lewy body disease (DLBD), six with progressive supranuclear palsy (PSP) and five with Parkinson's disease (PD) as well as 20 normal subjects were examined to detect apolipoprotein E (ApoE) by immunohistochemistry and immunoblotting. ApoE antigenicity was optimally preserved in Bouin-fixed tissues compared with those fixed in neutral-buffered formalin, 70% ethanol or denatured by microwave energy. ApoE immunoreactivity was prominent in senile plaques and in intra- and extra-neuronal tangles, as well as in a diverse neurones and their processes and astroglial cells. Notably, tangles in PSP and Lewy bodies in PD and DLBD were both devoid of ApoE immunoreactivity. Western blots of cerebral cortex revealed an immunoreactive ApoE band with mol. wt of 34 kDa. Our results suggest that ApoE is not a crucial factor in the development of neuronal inclusions in DLBD, PSP and PD. 相似文献
63.
Y Terada T Mitsui S Matsushita N Atsumi T Jikuya Y Sakakibara 《Canadian Metallurgical Quarterly》1995,60(2):422-425
BACKGROUND: Late potentials (LPs) after myocardial infarction identify the risk of arrhythmic events and sudden death, and the absence of anterograde flow in the infarct-causing occluded coronary artery frequently is associated with LPs on signal-averaged electrocardiography. The present study was designed to clarify the influence of revascularization of the infarct artery on the LPs in the late course after myocardial infarction. METHODS: We studied 21 patients after myocardial infarction with positive LPs who had at least one occluded infarct coronary artery. We investigated the LPs on signal-averaged electrocardiograms on the day of elective coronary artery bypass grafting (CABG) and 1 week after CABG. RESULTS: There were 25 infarct arteries in the study patients, 13 of which were grafted. The positive LPs disappeared soon after CABG in 13 patients, 10 of whom had grafts to all of the infarct arteries. The LPs persisted in 8, who received no graft to the infarct artery. One week after CABG, the LPs were still present in 4, all of whom had no graft to the infarct right coronary artery. CONCLUSIONS: In patients with positive LPs late after myocardial infarction, grafting to the infarct artery eliminated the LPs soon after CABG. 相似文献
64.
Carbonated autoclaved aerated concretes (AACs) show no shrinkage at a degree of carbonation approximately less than 20%. The 29Si MAS NMR spectrum showed that at a degree of carbonation less than 25%, the typical double-chain silicate anion structure of tobermorite-11Å was well maintained and interlayer Ca ions were exchanged with protons. This corresponded to the absence of carbonation shrinkage at a degree of carbonation less than 20%. When the degree of carbonation increased from 25% to 50% up to 60%, the double-chain silicate anion structure of tobermorite-11Å was decomposed and Ca ions in the Ca-O layers were dissolved, showing a possible mechanism of carbonation shrinkage. 相似文献
65.
Colloidal Processing and Mechanical Properties of Whisker-Reinforced Mullite Matrix Composites 总被引:2,自引:0,他引:2
Yoshihiro Hirata Shinichi Matsushita Yoshimi Ishihara Hiroaki Katsuki 《Journal of the American Ceramic Society》1991,74(10):2438-2442
Aqueous colloidal suspensions in the two systems of CVD-processed ultrafine mullite powder (<0.1 μm), -Si3 N4 whisker and -mullite whisker, were prepared near the isoelectric point of mullite (pH 7.0) to prevent cracking during drying of wet green compacts consolidated by filtration. The freeze-dried porous green compacts were hot-pressed with a carbon die at 1500°C for 1 h at a pressure of 39 MPa in N2 atmosphere. The relative densities of the mullite matrix composites with whiskers of 0 to 10 vol% were in the range of 95.2% to 99.8%. Increasing the fraction of Si3 N4 whisker increased the density, flexural strength, and fracture toughness of the hot-pressed composites. On the other hand, addition of the mullite whisker increased the fracture toughness but decreased the density and strength of the composites. 相似文献
66.
Between July 1991 and February 1995, 33 patients underwent bipolar shoulder arthroplasty for painful rotator cuff arthropathy of the shoulder. Twenty-two of these patients have been followed for an average of 28 months (range 24 to 48 months) and comprised the study group. All patients had massive, irreparable rotator cuff tears and presented with preserved passive motion, good deltoid function, and obliterated glenohumeral joint surfaces. Function and comfort were dramatically improved in all patients, with an average increase in active forward elevation of 29 degrees and a gain in active external rotation of 39 degrees. There was one complication requiring reoperation at 4 years. Utilizing the UCLA and Swanson scoring systems, all patients were rated fair or better. 相似文献
67.
M. Ellis P.R. HobsonP. Kyberd J.J. NebrenskyA. Bross J. FaganT. Fitzpatrick R. FloresR. Kubinski J. KriderR. Rucinski P. RubinovC. Tolian T.L. Hart D.M. KaplanW. Luebke B. FreemireM. Wojcik G. BarberD. Clark I. ClarkP.J. Dornan A. FishS. Greenwood R. HareA. Jamdagni V. KaseyM. Khaleeq J. LeaverK.R. Long E. McKigney T. Matsushita C. Rogers T. SashalmiP. Savage M. Takahashi A. TapperK. Yoshimura P. CookeR. Gamet H. SakamotoY. Kuno A. SatoT. Yano M. YoshidaC. MacWaters L. ConeyG. Hanson A. Klier D. ClineX. Yang D. Adey 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,659(1):136-153
68.
Jayawardana BC Hirano T Han KH Ishii H Okada T Shibayama S Fukushima M Sekikawa M Shimada K 《Meat science》2011,89(2):150-153
A commercial adzuki bean extract (AE) was evaluated for antioxidant effectiveness in cured and uncured cooked pork sausages. TBARS values, instrumental color evaluation and sensory panel scores were assessed. For uncured sausages, AE at 0.2% was equally effective as 0.1% butylated hydroxytoluene (BHT) in reducing TBARS values. Similarly, AE at 0.2% significantly (P<0.01) reduced the TBARS in cured sausages. Incorporation of 0.2% AE into sausages produced higher (P<0.05) CIE lab color a* value and lower (P<0.05) L* and b* values. Sensory panels did not detect any difference in color, odor, taste, flavor, and overall acceptance in uncured pork sausages with addition of 0.2% AE. However, there were adverse changes in the color and odor of cured sausages, even though the taste, flavor, and overall acceptance were similar. Therefore, the results suggest that AE is a potential antioxidant. 相似文献
69.
Pattanayak DK Yamaguchi S Matsushita T Kokubo T 《Journal of materials science. Materials in medicine》2011,22(8):1803-1812
Nanometer-scale roughness was generated on the surface of titanium (Ti) metal by NaOH treatment and remained after subsequent
acid treatment with HCl, HNO3 or H2SO4 solution, as long as the acid concentration was not high. It also remained after heat treatment. Sodium hydrogen titanate
produced by NaOH treatment was transformed into hydrogen titanate after subsequent acid treatment as long as the acid concentration
was not high. The hydrogen titanate was then transformed into titanium oxide (TiO2) of anatase and rutile by heat treatment. Treated Ti metals exhibited high apatite-forming abilities in a simulated body
fluid especially when the acid concentration was greater than 10 mM, irrespective of the type of acid solutions used. This
high apatite-forming ability was maintained in humid environments for long periods. The high apatite-forming ability was attributed
to the positive surface charge that formed on the TiO2 layer and not to the surface roughness or a specific crystalline phase. This positively charged TiO2 induced apatite formation by first selectively adsorbing negatively charged phosphate ions followed by positively charged
calcium ions. Apatite formation is expected on the surfaces of such treated Ti metals after short periods, even in living
systems. The bonding of metal to living bone is also expected to take place through this apatite layer. 相似文献
70.
New-type solar cells, having a structure “transparent conductor/thin Si02 layer with ultrafine metal islands as conductive channels/n-Si” have been prepared by forming a very thin (< 1.0 nm) silicon oxide (Si02) layer as well as platinum (Pt) islands (5–50 nm in size) embedded in it on a single crystal n-type silicon (n-Si) wafer, followed by the deposition of an indium tin oxide (ITO) film (200 nm thick) by the electron-beam evaporation method. The open-circuit photovoltages (Voc) of the solar cells of the above structure were relatively low, 0.25–0.47 V, but they increased very much to 0.50–0.59 V if a thin (3–10 nm) layer of an organic compound such as copper phthalocyanine (CuPc) was pre-deposited on the Pt-island modified n-Si wafer before the ITO deposition. The reason for the beneficial effect of the pre-deposition of the thin CuPc layer was investigated in detail, and it has been found that certain crystal defects are formed in n-Si near the n-Si/Si02 interface during the ITO deposition in the absence of the CuPc layer. The formation of such defects is prevented in the presence of the CuPc layer, which leads to a decrease in surface carrier recombination and hence to the increase in Voc. 相似文献