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排序方式: 共有1327条查询结果,搜索用时 15 毫秒
991.
K Omija J Tokumine H Iha M Uehara K Nitta Y Okuda 《Canadian Metallurgical Quarterly》1997,46(10):1385-1389
"The low flow leak test" is recommended for pre-anesthetic inspection of anesthetic machines. We carried out anesthesia compression tests as a standard. Even in that case, often the low flow leak test does not meet the standard. We investigated the point where there is a leak in the anesthetic machine. Observing the leak that fluctuates each time there is detachment or attachment of the canister, the primary cause of the leak is thought to be related to the canister. It is important to carry out an inspection of the canister if the low flow leak test does not meet the standard. 相似文献
992.
T Yamada T Ozawa F Gejyo Y Okuda K Takasugi O Hotta Y Itoh 《Canadian Metallurgical Quarterly》1998,57(4):249-251
BACKGROUND: Intrapericardial teratomas are rare and usually present early in infancy or childhood. PROCEDURE: We describe herein a rare case of an adult patient with an intrapericardial teratoma who presented with fever, cardiac arrhythmias, and oppressive substernal chest pain. Preoperative diagnosis was suggested by echocardiography and computerized tomography of the chest. The tumor weighed 530 g and its histologic features were those of a mature cystic teratoma. It was excised totally and 10 years' follow-up revealed no evidence of residual disease. DISCUSSION: Our patient is one of the very few adult patients with intrapericardial teratomas who was treated successfully with surgery. Both echocardiography and tomography of the chest suggested the diagnosis and delineated the relationship of the tumor to the great vessels. CONCLUSION: The diagnosis of Intrapericardial teratomas is suspected by echocardiography and/or tomography of the chest and confirmed by specific histologic features. These tumors should be excised whenever detected. 相似文献
993.
S Sasaki K Sumino K Hamajima J Fukushima N Ishii S Kawamoto H Mohri CR Kensil K Okuda 《Canadian Metallurgical Quarterly》1998,72(6):4931-4939
Induction of mucosal and cell-mediated immunity is critical for development of an effective vaccine against human immunodeficiency virus (HIV). We compared intramuscular and intranasal immunizations with a DNA vaccine encoding env of HIV-1 and evaluated the QS-21 saponin adjuvant for augmentation of the systemic and mucosal immune responses to HIV-1 in a murine model. Vaccination via the two routes elicited comparable systemic immune responses, and QS-21 consistently enhanced antigen-specific serum immunoglobulin G2a (IgG2a) production, delayed-type hypersensitivity reaction, and cytolytic activity of splenocytes. Intestinal secretory IgA production and cytolytic activity of the mesenteric lymph node cells are preferentially elicited by intranasal immunization, and QS-21 augmented these activities as well. This adjuvant augmented production of interleukin-2 (IL-2) and gamma interferon (IFN-gamma) associated with decrease in IL-4 synthesis by antigen-restimulated splenocytes. The serum immunoglobulin subtype profile showed a dominant IgG2a response and less strong IgG1 and IgE production in a QS-21 dose-dependent manner. As expected, enhancements of humoral and cell-mediated immune responses by QS-21 were abrogated by treatment with anti-IL-2 and anti-IFN-gamma monoclonal antibodies. These results suggest that the intranasal route of DNA immunization is more efficient than the intramuscular route in inducing mucosal immunity mediated by sIgA and mesenteric lymphocytes. Furthermore, QS-21 is able to act as a mucosal adjuvant in DNA vaccination and demonstrates its immunomodulatory property via stimulation of the Th1 subset. This study emphasizes the importance of the route of immunization and the use of an adjuvant for effective DNA vaccination against HIV-1. 相似文献
994.
T Kawabata J Tokumine I Takara O Kakinohara H Iha Y Okuda 《Canadian Metallurgical Quarterly》1998,47(12):1437-1443
The purpose of this study was to evaluate the safety and advantage of intra-operative patient-controlled sedation (PCS) in elderly patients. Propofol PCS was compared with anesthesiologist-controlled sedation (ACS) during knee arthroplasty under epidural anesthesia. Eleven elderly patients scheduled for unilateral knee total or partial arthroplasty were divided randomly into PCS group (n = 6) and ACS group (n = 5). Epidural anesthesia was performed to produce an appropriate level of sensory block (T 10 through S). Firstly a mixture of pentazocine 0.2 mg.kg-1 and 2% mepivacaine 6-9 ml was injected to the epidural space, and anaesthesia was maintained using 2% mepivacaine afterward. Patients in both groups received propofol 0.3 mg.kg-1 i.v. as a loading dose and 0.6 mg.kg-1.h-1 continuous infusion. Furthermore patients in PCS group received propofol PCS (bolus: 0.2 mg.kg-1, lockout time: 3 min). Patients in ACS group were administered propofol continuously and infusion rates were regulated to maintain a sedation score 3 (Wilson et al) by anesthesiologist. Respiratory rate, blood pressure, heart rate, SpO2, arterial blood gas analysis and plasma levels of propofol were measured 4 times during and after the surgery. Satisfaction of patients and surgeons was questioned. Patients in PCS group received a mean propofol dose of 1.9 +/- 0.1 mg.kg-1 during procedures with a mean duration of 147 min. On the other hand patients in ACS group received propofol 2.9 +/- 0.3 mg.kg-1 with 142 min of procedures. Satisfaction of patients and surgeons, the incidence of complication were similar between the groups. For elderly patients who undergo epidural anesthesia, PCS is a safe and effective technique providing similar good sedation as with ACS. 相似文献
995.
T Ogata K Okuda S Tanaka J Shibata A Koga H Kinoshita T Nakayama S Aoyagi M Tanaka K Tanikawa 《Canadian Metallurgical Quarterly》1997,24(12):1661-1664
Gamma irradiation sensitivity of a strain of Listeria monocytogenes was determined in trypticase soy broth supplemented with yeast extract (TSB-YE), in a slurry of chicken breast meat and in raw ground beef. D10 values in these different media were 0.364, 0.599, and 0.699 kGy, respectively. This organism appeared most sensitive in TSB-YE, more resistant in minced fresh chicken breast meat, and most resistant in fresh minced beef. It was found that irradiation at 2.5 kGy prior to refrigeration is an efficient way for the preservation of meat products contaminated at 10(3) to 10(4) per gram initial load of L. monocytogenes for about 7 d. However, with this initial load, the injured cells might repair themselves and cause a health hazard during storage at 4 C in the presence of air after 7 d. 相似文献
996.
H Imayama K Nakayama H Kinoshita K Okuda M Hara S Fukuda A Hasuda 《Canadian Metallurgical Quarterly》1997,86(4):640-645
Genetically engineered structural variants of human beta2-microglobulin (beta2m) were produced by sequence exchange with mouse beta2m for the purpose of examining species-specific antigenic determinant expression. For aggregate mapping, mouse and human beta2m, which differ by 30% in their primary sequence of 99 amino acids, were prepared as chimeric (human X mouse) molecules and expressed in the FO-1 beta2m-null human melanoma cell line. A chimera containing residues 1-69 from human beta2m (and residues 70-99 from mouse beta2m) induced expression of the epitopes defined by the anti-beta2m monoclonal antibodies (mAb) BBM.1, NAMB-1, and L368; the reverse chimera did not, although HLA class I heavy chain was evident on the cell surface as determined with the TP25.99 mAb. For fine dissection of the epitopes defined by these mAbs, site-directed mutants of beta2m were prepared by replacement of individual amino acids in human beta2m with the dimorphic residue from mouse beta2m. Substitutions were made at each divergent residue between positions 1 and 66 and, as controls for COOH-terminal modification, a series of residues between positions 75 and 94. Replacement of amino acids 38, 44, and 45, but not 16 other dimorphic residues in the linear stretch from residue 1 to residue 66, resulted in the loss of, or gross reduction in, binding by mAbs BBM.1 and NAMB-1. A reduction in binding was also observed for mAb L368. These data provide strong evidence that the antigenic epitopes defined by these mAb map to a region including S3 and its adjacent intra-beta-strand turn of the three-stranded beta-pleated sheet of beta2m. The mapping of these epitopes is consistent with their accessibility in the assembled major histocompatibility complex class I molecule and indicates that the region from amino acid 38 to 45 is an important structural feature in the "foreignness" of human and mouse beta2m. 相似文献
997.
To evaluate the usefulness of MIBI scintigraphy (MIBI) for parathyroid lesions, the detectability of lesions by MIBI was compared with that by Tl-Tc subtraction imaging, ultrasonography, CT and MRI in 56 histologically proved lesions. In neck lesions, ultrasonography (92%) and MIBI (85%) showed better detectability than those by the other three modalities. With MIBI, detectability was decreased for smaller parathyroid lesions that coexisted with thyroid disease. Among the five modalities, MIBI showed the highest detectability (88%) for ectopic or metastatic lesions. The smallest parathyroid lesions detected by MIBI were a parathyroid adenoma weighing 220mg and a parathyroid hyperplasia weighing 200mg. MIBI was thought to be more valuable for ectopic or metastatic parathyroid lesions. 相似文献
998.
999.
Coarsening kinetics of multicomponent MC-type carbides in high-strength low-alloy steels 总被引:2,自引:0,他引:2
Kaori Miyata Takahiro Kushida Tomohiro Omura Yuichi Komizo 《Metallurgical and Materials Transactions A》2003,34(8):1565-1573
Morphology and coarsening kinetics of MC-type carbide (MC-carbide) precipitating during the tempering process have been investigated
in V- and Nb-bearing Cr-Mo martensitic steels. Detailed transmission electron microscopy (TEM) observations show that the
addition of V and Nb stabilizes the B1-type MC-carbide instead of L’3-type M2C-carbide. The morphology of the MC-carbide is characterized as disk-like with Baker and Nutting orientation relationships
with the matrix. When the specimens are fully solution treated followed by quenching, the MC-carbide precipitates as a multicomponent
system with continuous solid solution of VC, NbC, and MoC. The V-, Nb-, and Mo-partitioning control the lattice parameter
of MC-carbide and consequently affect the coherency between MC-carbide and the matrix. The coherent MC-carbide grows into
an incoherent one with the progress of tempering. The numerical analysis on TEM observations has shown that the coarsening
kinetics of MC-carbide is equated to (time)1/5 criteria, while the coarsening kinetics of the coexisting cementite is equated to (time)1/3 criteria. It is thus suggested that the Ostwald ripening of MC-carbide is controlled by pipe diffusion of V, Nb, and Mo along
dislocations. It has been confirmed that the coarsening rate of the multicomponent MC-carbide is affected by V, Nb, and Mo
content. Applying the thermodynamic solution database, the rate equation for MC-carbide coarsening can be expressed as a function
of V, Nb, and Mo content, and the activation energy for pipe diffusion can be estimated as ΔQ
v: ΔQ
Nb: ΔQ
Mo=1:3.9:0.6. 相似文献
1000.
Masaru Kanazawa Yuichi Kusakabe Yuji Nojiri Yasuyuki Haino Masahito Sato Keiichirou Doi 《Journal of the Society for Information Display》2007,15(10):837-843
Abstract— For future broadcasting, NHK is studying new video services offering very‐high‐picture quality achieved through Super Hi‐Vision. Toward that aim, a projection display that has a resolution equivalent to 7680 × 4320 pixels by using four 4096 × 2160 D‐ILA? panels has been developed. The display requires precise convergence adjustment because it consists of two projection units, so an automatic adjustment system was developed. Although the pixel number of the digital camera used is less than that of the display, a 0.2‐pixel accuracy was obtained. This report introduces theaters that use this display as an example of applying the Super Hi‐Vision video system. 相似文献