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151.
152.
H Ohara M Hoshino T Hayakawa Y Kamiya M Miyaji T Takeuchi Y Okayama K Gotoh 《Canadian Metallurgical Quarterly》1996,91(7):1388-1394
OBJECTIVES: We performed extracorporeal shock wave lithotripsy (ESWL) as the treatment of first choice on 32 chronic pancreatitis patients with main pancreatic duct (MPD) stones prospectively to establish more convenient and safer treatment. METHODS: All patients were treated in a prone position, and shock waves were discharged from the ventral side. ESWL was performed once or twice a week, and no other treatments before ESWL had been applied. RESULTS: Disintegration of all MPD stones to 3 mm or less in diameter could be achieved in all treated patients. Complete clearance of the stones was obtained in 24 patients (75%) without the necessity of endoscopic extraction of fragments. Reduction of MPD diameters after ESWL was statistically significant (p < 0.01). Epigastric and/or back pain complaints before ESWL were completely alleviated in 79% (periods of follow-up: 16-63 months, mean 44), and the pancreatic exocrine function also improved in 61%. No severe complications occurred in any of the patients. CONCLUSIONS: ESWL, which is comparatively easy to perform, is a safe and efficient approach that changes endoscopy's status as an indispensable pretreatment. Therefore, ESWL can be recommended as the first choice treatment for patients with chronic pancreatitis accompanied by MPD stones that should be tried before consideration of either surgical or endoscopic procedures. 相似文献
153.
Eighty-five cemented total knee arthroplasties were followed for five to fourteen years (mean 7.8 years). The clinical evaluation was excellent or good in 85% of this series. However, a complication developed in 15 knees (17.6%), and two thirds of these complications were found in the patello-femoral joint. One further case developed an infection (1.2%), and four others (4.7%) developed an aseptic loosening. Over all, 8 cases (9.4%) required revision surgery. Asymptomatic wear was seen to progress in some implants involving thin polyethylene, although their clinical results were rated as excellent. The outcome of the cemented knee arthroplasties was considered as acceptable at present, but improved surgical techniques and measures against polyethylene wear are required for future improvement in this surgery. 相似文献
154.
Piezoelectric and ferroelectric properties of bismuth sodium titanate, (Bi1/2Na1/2)TiO3(BNT)-based solid solution, that is, (Bi1/2Na1/2)(1-x)(Pba Bab)xTiO3(a + b = 1) [BNPB(100x-100a/100b)], are studied from the viewpoint of a new group of lead-free or low-lead content piezo-electric ceramics with a rhombohedral(Fa-tetragonal (Fβ) morphotropic phase boundary (MPB). It is evident that the MPB seems to be remarkably efficacious in promoting piezoelectric and pyroelectric activities by electrical poling. X-ray diffraction data, dielectric properties and D-E hysteresis loops show that the MPB exist near (Bi1/2Na1/2)TiO3[BNT] at x = 0.13–0.14, 0.08–0.09 and 0.06–0.07 in the case of b = 0, b = 0.5 and b = 1, respectively. BNPB ceramics are superior for piezoelectric ceramics in high-frequency ultrasonic uses, or special piezoelectric actuator materials with a lower free permittivity ε33Tε0, and a high electromechanical coupling factor k33, along with a high mechanical strength. 相似文献
155.
The components of self-regulation were analyzed, extending the self-imposed delay of gratification paradigm to older children with social adjustment problems. Delay behavior was related to a network of conceptually relevant cognitive person variables, consisting of attention deployment strategies during delay, knowledge of delay rules, and intelligence. A positive relationship was demonstrated between concurrent indexes of intelligence, attention deployment, and actual delay time. Moreover, attention deployment, measured as an individual differences variable during the delay process, had a direct, positive effect on delay behavior. Specifically, as the duration of delay and the frustration of the situation increased, children who spent a higher proportion of the time distracting themselves from the tempting elements of the delay situation were able to delay longer. The effect of attention deployment on delay behavior was significant even when age, intelligence, and delay rule knowledge were controlled. Likewise, delay rule knowledge significantly predicted delay time, even when age, attention deployment, and intelligence were controlled. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
156.
Growth of Thermus thermophilus HB27 was inhibited by a proline analog, 3,4-dehydroproline (DHP). This result suggested that the gamma-glutamyl kinase (the product of the proB gene) was inhibited by feedback inhibition in T. thermophilus. DHP-resistant mutants were reported previously for Escherichia coli (A. M. Dandekar and S. L. Uratsu, J. Bacteriol. 170:5943-5945, 1988) and Serratia marcescens (K. Omori, S. Suzuki, Y. Imai, and S. Komatsubara, J. Gen. Microbiol. 138:693-699, 1992), and their mutated sites in the proB gene were identified. Comparison of the amino acid sequence of T. thermophilus gamma-glutamyl kinase with those of E. coli and S. marcescens mutants revealed that the DHP resistance mutations occurred in the amino acids conserved among the three organisms. For eliminating the feedback inhibition, we first constructed a DHP-resistant mutant, TH401, by site-directed mutagenesis at the proB gene as reported for the proline-producing mutant of S. marcescens. The mutant, TH401, excreted about 1 mg of L-proline per liter at 70 degreesC after 12 h of incubation. It was also suggested that T. thermophilus had a proline degradation and transport pathway since it was able to grow in minimal medium containing L-proline as sole nitrogen source. In order to disrupt the proline degradation or transport genes, TH401 was mutated by UV irradiation. Seven mutants unable to utilize L-proline for their growth were isolated. One of the mutants, TH4017, excreted about 2 mg of L-proline per liter in minimal medium at 70 degreesC after 12 h of incubation. 相似文献
157.
To examine the effects of the relationships between behavior and the situation in which it occurs, we manipulated such relations and exposed subjects to them. Impressions were similar when based on the behaviors presented with situations unspecified (e.g., child hits) or when the situations in which they naturally occurred were specified (e.g., child hits when provoked). However, when situations were specified, subjects' impressions more accurately predicted individual differences in the children's actual levels of overall aggressive behavior. When the veridical situation–behavior relations were increasingly altered, the targets were perceived as being less plausible and increasingly maladjusted and odd, and correlations decreased between the perceived level of the children's aggressiveness and their actual aggressive behavior. Thus, both personality impressions and predictive accuracy were influenced by the relations between the target's behaviors and their situational contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
158.
M Motomura T Hoshino G Tomonaga S Morioka Y Shimono 《Canadian Metallurgical Quarterly》1977,41(9):983-989
Thirteen patients with aortic regurgitation (AR) and 13 with mitral regurgitation (MR) were compared quantitatively from the standpoint of their vector-cardiograms (VCG). Vectorcardiographic parameters were also compared with left ventricular angiographic parameters. The QR time interval was longer and the magnitude of the spatial maximum QRS vector was larger in the AR group, but these differences were thought to be attributed to the differences in length of the left ventricular long axis and the left ventricular end diastolic volume (LVEDV). In the AR group, the ratio of the width to the long axis of the QRS loop in the horizontal plane correlated well with the length of the left ventricular long axis and the angle made by the axis from the middle of the aortic valve to the left ventricular apex and the horizontal axis in the lateral view of the angiogram. In the MR group, these correlations were poor. 相似文献
159.
J Guzowski MM Paparella K Nageswara T Hoshino 《Canadian Metallurgical Quarterly》1976,86(8):1141-1146
Meningiomas should be considered in the differential diagnosis of otologic tumors arising from the middle ear and mastoid. It is generally recognized that meningiomas may invade the temporal bone via direct extension from the intracranial space (secondary). It is not generally recognized that meningiomas can develop initially in the middle ear cleft (primary). Representative cases of primary and secondary meningiomas of the temporal bone are described and clinical aspects of diagnosis surgical management are discussed. In order to assess the pathogenesis of meningiomas of the temporal bone, histological studies were done on 200 temporal bone specimens. In certain specimens, ectopic arachnoid granulations, from which primary meningiomas may originate, were identified and described, according to location. One specimen was most unusual in that it contained ectopic glial as well as arachnoidal tissue. 相似文献
160.
Kazutomo Hoshino Yoshiaki IIjima Ken-Ichi Hirano 《Metallurgical and Materials Transactions A》1982,13(7):1135-1139
Interdiffusion coefficients in copper-rich copper-zinc solid solutions containing up to 8 at. pct of Zn at 1168 K have been
determined by Matano's analysis using semi-infinite diffusion couples consisting of pure copper and Cu-Zn alloys with Kirkendall
markers. From the marker shift and Darken's relation, intrinsic diffusion coefficients, DZn and DCu, in the alloys containing 3.2 and 4.7 at. pct of Zn have been determined. Further, using thin plate couples, DZn and DCu in Cu alloys containing 0.9, 2.3, 3.5, and 4.6 at. pct of Zn at 1168 K have been determined by Heumann's method. The ratio
of the intrinsic diffusion coefficients, DZn/DCu, has been found to be about two for all the compositions examined. Using the values of the intrinsic diffusion coefficient
of copper at infinite dilution of zinc obtained by extrapolating the concentration dependence of DCu, and the self- and impurity diffusion coefficients in pure copper, the vacancy flow factor has been estimated to be - 0.22-0.15
+0.06 at 1168 K. By combining this value of the vacancy flow factor with the solute enhancement factor of solvent diffusion determined
by Peterson and Rothman, the correlation factor for impurity diffusion of Zn in Cu at 1168 K has been evaluated to be 0.5,
which is in good agreement with the value of 0.47 determined by Peterson and Rothman based on the isotope effect measurement.
KAZUTOMO HOSHINO, formerly Graduate Student, Tohoku University is now with Materials Science Division, Argonne National Laboratory,
Argonne, IL 60439. YOSHIAKI IIJIMA, Instructor, and KENICHI HIRANO, Professor, are both with the Department of Materials Science,
Faculty of Engineering, Tohoku University, Sendai 980, Japan. 相似文献