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81.
S. Nakao K. Ueno T. Hanaguri K. Kitazawa T. Fujita Y. Nakayama T. Motohashi J. Shimoyama K. Kishio T. Hasegawa 《Journal of Low Temperature Physics》1999,117(3-4):341-345
We have performed scanning tunneling microscopy/spectroscopy (STM/STS) on single crystals of heavily Pb-doped Bi
2
Sr
2
CaCu
2
O
y
(Pb-Bi2212). The obtained STM images clearly demonstrated phase separation into the and phases with lamella-type and new zigzag-like microstructures. From the site-specified tunneling measurements, it was directly confirmed that the phase possesses higher T
c
. This suggests that the phase boundaries act as strong pinning sites especially at higher temperatures. 相似文献
82.
Under magnetic fields perpendicular to the conductive plane in quasi-two-dimensional organic conductors: -(BEDT-TTF)2
MHg(SCN)4 (M= K, Rb, and Tl), the experimentally reported H–T phase diagram has been explained partially. By the self-consistent numerical calculation including the quantum magnetic oscillation and the magnetic breakdown; in addition to the imperfectness of the SDW nesting, we try to completely understand the phase diagram. 相似文献
83.
Miida T. Hasegawa Y. Hagiwara T. Ohshiba H. 《Solid-State Circuits, IEEE Journal of》1991,26(12):1915-1919
The authors describe a charge coupled device (CCD) sense amplifier in a video delay line which overcomes the major limitations of conventional floating diffusion amplifier (FDA) technology, such as limited output voltage and operating temperature range. These advances are implemented with a switched-capacitor integrator (SCI) using an op amp with a newly developed output stage in a CMOS-CCD process. This circuit is effected within the constraints of 5-V operation by using negative pulses to reach the low channel potential of the CCD in the pinning region in the final gate of the CCD. The chip operates with 14.3-MHz clock and 5-V power supply, and can process a 1.0-Vp-p signal voltage under 1% distortion, and under 4% gain variation from -20 to 70°C 相似文献
84.
Gradient estimation via smoothed perturbation analysis (SPA) is considered for the multiclass single-server priority queue. Although the problem like this requires additional subpaths, generally it is shown that the estimators can be derived without any additional sample paths 相似文献
85.
86.
87.
BACKGROUND: Single small enhancing computerized tomographic (CT) lesions (SSECTLs) are common in children with focal seizures. These are considered to represent solitary cysticercus granulomas. Controversy exists regarding their treatment. OBJECTIVE: To evaluate the efficacy of albendazole in cases of focal seizures with SSECTLs. DESIGN: Randomized, placebo-controlled, double blind trial. SETTING: Pediatric service of Nehru Hospital, PGIMER, an urban tertiary care teaching hospital. SUBJECTS: 63 children between 2 and 12 years of age with focal seizures for <3 months and SSECTLs. INTERVENTION: All children were randomly assigned to receive either albendazole (15 mg/kg/ day) or placebo for 28 days. CT scan was done at 1 and 3 months after beginning treatment. Codes opened after 6 months of inclusion in the study showed that 31 had received albendazole and 32 had received placebo. All children were followed up for at least 15 months. RESULTS: Disappearance of lesions on CT scan was noted in 41% of albendazole vs. 16.2% of placebo patients after 1 month of follow-up (P < 0.05) and 64.5% of albendazole- vs. 37.5% of placebo-treated patients after 3 months of follow-up (P < 0.05). During the first 4 weeks of therapy seizure recurrence was seen in 9.7% of albendazole vs. 3.2% of placebo-treated children (odds ratio, 3.32; 95% confidence interval, 0.33 to 33.8). After 4 weeks seizure recurrence was seen in 31.3% of placebo-treated children vs. 12.9% of albendazole-treated children (odds ratio, 3.07; 95% confidence interval, 1.18 to 11.15). CONCLUSIONS: Albendazole therapy results in significantly faster and increased resolution of solitary cysticercus lesions (SSECTLs) and appears to reduce the risk of late seizure recurrences. 相似文献
88.
89.
M Sumi H Satoh M Ohtsuka S Hasegawa M Fujiwara H Kamma 《Canadian Metallurgical Quarterly》1998,5(6):1439-1440
Malignant lymphomas arise in the pleura in association with a long-standing chronic tuberculous pyothorax. We report a case of a non-Hodgkin's lymphoma of the pleural cavity, inoperable because of local invasion into thoracic wall, who has survived more than 6 years without recurrence. This patient represents the longest reported survival after radiation therapy alone. Radiotherapy holds an important role in the treatment of locally advanced lymphoma of the pleural cavity. 相似文献
90.
Phosphatidylserine (PtdSer) synthesis in Chinese hamster ovary (CHO) cells occurs through the exchange of L-serine with the base moiety of phosphatidylcholine or phosphatidylethanolamine. The synthesis is depressed on the addition of PtdSer to the culture medium. A CHO cell mutant named mutant 29, whose PtdSer biosynthesis is highly resistant to this depression by exogenous PtdSer, has been isolated from CHO-K1 cells. In the present study, the PtdSer-resistant PtdSer biosynthesis in the mutant was traced to a point mutation in the PtdSer synthase I gene, pssA, resulting in the replacement of Arg-95 of the synthase by lysine. Introduction of the mutant pssA cDNA, but not the wild-type pssA cDNA, into CHO-K1 cells induced the PtdSer-resistant PtdSer biosynthesis. In a cell-free system, the serine base-exchange activity of the wild-type pssA-transfected cells was inhibited by PtdSer, but that of the mutant pssA-transfected cells was resistant to the inhibition. Like the mutant 29 cells, the mutant pssA-transfected cells grown without exogenous PtdSer exhibited an approximately 2-fold increase in the cellular PtdSer level compared with that in CHO-K1 cells, although the wild-type pssA-transfected cells did not exhibit such a significant increase. These results indicated that the inhibition of PtdSer synthase I by PtdSer is essential for the maintenance of a normal PtdSer level in CHO-K1 cells and that Arg-95 of the synthase is a crucial residue for the inhibition. 相似文献