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991.
A Murata Y Taniguchi Y Hashimoto Y Kaneko Y Takasaki S Kudoh 《Canadian Metallurgical Quarterly》1998,37(9):732-735
SETTING: Sixteen districts of Budapest, Hungary. OBJECTIVE: To determine the frequency of primary and secondary drug resistance, and to recommend treatment regimens. DESIGN: A retrospective survey. METHODS: Mycobacterium tuberculosis isolates were collected from 264 newly diagnosed and 147 previously treated patients. All strains were tested against isoniazid (INH), rifampicin (RIF), streptomycin (SM) and ethambutol (EMB) using the proportion method. Bacteriologic examinations were performed in the Diagnostic Laboratory of the Koranyi National Institute for Tuberculosis and Pulmonology in Budapest. RESULTS: Primary resistance to INH alone was 4%, to SM alone 2%, to RIF alone 0.4%, to INH and SM 1%, and to INH, RIF, SM and EMB 0.4%. Of the isolates of 78 relapse cases, six (8%) were resistant to INH alone, one (1%) to INH and RIF, two (3%) to INH, RIF, SM and EMB. Of the isolates of 69 patients notified with active tuberculosis for over a year, 51 (74%) were susceptible to the drugs tested. CONCLUSION: Based on the level of primary drug resistance as well as on the resistance pattern of relapse cases, it is recommended to start the treatment of newly detected and relapse cases with four drugs. The high rate of chronic cases with susceptible strains can be explained by poor compliance. To prevent development of resistant cases and to achieve good compliance, it is necessary to apply direct observation of treatment in all types of patients. 相似文献
992.
M Zaima K Nagamatsu A Mitsuyoshi S Murata T Takeuchi A Kobayashi 《Canadian Metallurgical Quarterly》1997,49(6):948-950
A 36-year-old woman had uneventful astigmatic myopic laser in situ keratomileusis (LASIK) to correct -12.00 -1.50 x 70. Three days later, she developed a corneal abscess, hypopyon, and an intense vitreous cellular reaction-endophthalmitis. The patient was immediately given intravenous ciprofloxacin and topical vancomycin and ceftazidime. The infecting organism was Streptococcus pneumoniae. One day after therapy was instituted, the hypopyon resolved. Seven months later, best corrected visual acuity was 20/25 and refractive error, -4.00 diopters. A stromal scar (grade 2 haze) was causing a slight reduction in acuity. Endophthalmitis after LASIK, if treated promptly, need not lead to a permanent reduction in visual acuity. 相似文献
993.
994.
Ken-Ichi Baba Masayuki Murata Hideo Miyahara 《International Journal of Communication Systems》1994,7(4):283-294
Broadband ISDN (integrated services digital network) should provide various kinds of communication services for multimedia traffic, including voice, computer data, still picture and motion video, and an ATM (asynchronous transfer mode) technology is expected to satisfy those demands. In ATM networks, a VP (virtual path) concept is introduced for simplifying the network resource management. However, if the bandwidth of each VP is fixed, it cannot absorb traffic load fluctuation. In this case, it is likely to happen that one VP has no remaining bandwidth while other VPs on the same physical link have free capacities. Another extremity is that a VP is not introduced, and that all VCs along the same physical link share the whole bandwidth of the link. This can achieve an efficient use of the link, but it apparently requires complicated call set-up procedures. In this paper, we propose a new dynamic VP bandwidth control method, in which the bandwidth allocated to each VP is dynamically changed according to traffic fluctuation. More specifically, in the case that multiple VPs are multiplexed on the same link between two nodes, when the utilization of some VP is increased, that VP requests an additional bandwidth. When the traffic load becomes low and the utilization of a VP is decreased, a part of the assigned bandwidth is released. We consider two methods for this purpose; one is the basic method in which the bandwidth increase request is issued after the VP bandwidth is exhausted. The other is the look-ahead method where the bandwidth increase is requested in advance before the bandwidth starvation. An approximate analysis for the above methods is provided, and the validation of its accuracy is assessed by comparing with simulation results. Through numerical examples, we show that our methods can provide performance improvement in terms of call loss probabilities of each VP. 相似文献
995.
Y Miyoshi K Iwao Y Nagasawa T Aihara Y Sasaki S Imaoka M Murata T Shimano Y Nakamura 《Canadian Metallurgical Quarterly》1998,58(12):2524-2527
We screened 75 primary hepatocellular carcinomas for somatic mutations in the entire coding region of the beta-catenin gene. We detected somatic mutations in 14 tumors; 12 were considered to cause amino acid substitutions and 2 were interstitial deletions of 51 or 195 nucleotides of genomic DNA, corresponding to exon 3. Among the 12 point mutations, 6 occurred at potential serine/threonine phosphorylation residues of codons 33, 41, or 45. The remaining six tumors contained a mutation at codon 32 (aspartic acid) or 34 (glycine), flanking to the serine residue at codon 33. By Western blot analysis, we confirmed accumulation of beta-catenin in five tumors for which frozen tissues were available; the five included tumors in which amino acid alterations had occurred at codons 32, 34, or 45, and one with a 17-amino acid deletion. Our results suggested that accumulation of beta-catenin due to amino acid substitutions at potential serine/threonine phosphorylation residues or at their neighboring codons or interstitial deletions involving exon 3 could contribute to hepatocellular carcinogenesis. 相似文献
996.
T Mae A Takazawa M Ikeda J Murata T Kaneko H Suzuki 《Canadian Metallurgical Quarterly》1997,46(3):331-337
The release of norepinephrine (NE) in the ventral hippocampus was studied in rats with microdialysis method. The basal release of NE with perfusion of normal artificial cerebrospinal fluid (ACSF) was 1.58 +/- 0.37 x 20 microliters-1 sample. The NE concentration increased significantly with perfusion of high potassium (60 mM) ACSF indicating that depolarization-induced release was up to 5 times higher than the basic level. Ketamine (20 mg.kg-1 and 80 mg.kg-1 im) significantly inhibited the depolarization-induced increase of NE, but did not affect the basal release. Neither 5 mg.kg-1 im of ketamine nor MK-801 had any effect on the basic or the depolarization-induced release. These results suggest that the inhibitory effect of ketamine on the depolarization-induced NE release was not due to the NMDA channel blocking properties of ketamine. 相似文献
997.
In nickel-based superalloys, the B1-type monocarbides contain several kinds of transition elements. At elevated temperatures, the monocarbides transform to other carbides, such as M23C6 and M6C as a result of the reaction with the alloy. The phase stability of monocarbides was investigated by X-ray diffraction techniques. The degree of stability is strongly affected by the composition of the monocarbides and is related generally to the magnitude of the lattice parameter of the monocarbides. That is, the larger the lattice parameters of the monocarbides, the higher their stability in nickel-based alloys. 相似文献
998.
N Masumoto Y Ikebuchi T Matsuoka K Tasaka A Miyake Y Murata 《Canadian Metallurgical Quarterly》1997,153(1):R5-10
The synaptic membrane protein synaptosomal-associated protein (SNAP-25) has recently been implicated as one of the key proteins involved in exocytotic membrane fusion in neurons. However, the role of SNAP-25 in pituitary hormone release is not known. In this study, we determined that SNAP-25 is involved in regulated exocytosis in the clonal pituitary cell line GH4C1. SNAP-25 messenger RNA and protein were detected in GH4C1 cells by RT-PCR and immunoblot analysis, respectively. Immunofluorescence analysis indicated that SNAP-25 protein was localized in the plasma membrane. Next, to determine the function of SNAP-25 in GH4C1 cells, specific inhibitors of SNAP-25, botulinum neurotoxin (BoNT)/A or /E, and antisense SNAP-25 oligonucleotide were used. Neither BoNT/A nor BoNT/E affected thyrotropin-releasing hormone (TRH)-induced cytosolic Ca2+ increase, but both inhibited TRH-induced exocytosis. Moreover, they dose-dependently inhibited TRH-induced prolactin release. The introduction of antisense oligonucleotide into the cells also inhibited TRH-induced prolactin release. These results suggest that SNAP-25 is involved in regulated exocytosis in GH4C1 cells. 相似文献
999.
A Petri Net-based real-time control software system for transaction processing is proposed to improve flexibility and maintainability in real-time application software. This software system is named Station Controller (SCR). Transaction processing control programs can be understandably described using Control Net (C-net) which is a problem-oriented language based on a colored safe Petri Net model. The described C-net program is directly executed by a net-interpreter installed on a 16-bit micro-computer system. In this paper, some features of the SCR are described and a successful application of the SCR is illustrated. 相似文献
1000.