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排序方式: 共有1510条查询结果,搜索用时 31 毫秒
161.
Recombinant Der f2 (rDer f2) has recently been developed as a promising allergen for the diagnosis and immunotherapy of house-dust mite allergy, and studies in immunology. The aim of the present study was to evaluate whether oral administration of rDer f2 could suppress an immediate allergic reaction in mice sensitized with mite allergen. We developed a murine allergic model that showed bronchoconstriction after inhalation of rDer f2, and studied the effect of oral administration of rDer f2 on the reaction. Seven week old male A/J mice were intranasally immunized with rDer f2 12 times. Sensitized mice showed anti-rDer f2 immunoglobulin (Ig)E production and immediate airway constriction after inhalation of 10 mg.mL(-1) of rDer f2, as determined by the Konzett-R?ssler method. Immunized animals were divided into three groups, and fed phosphate-buffered saline (PBS), 0.1 mg.day(-1), or 1 mg.day(-1) of rDer f2 for 4 weeks, respectively. Seven days after the last feeding, the mice were examined for their immediate response. Animals fed with 1 mg.day(-1) rDer f2 showed significantly reduced bronchoconstriction after inhalation of both 2 mg.mL(-1) and 10 mg.mL(-1) of rDer f2 compared with PBS-fed mice. Similar results were obtained when we examined mice 10 weeks after the last feeding. Reactions in the 0.1 mg.day(-1) rDer f2-fed group also tended to decrease in comparison with PBS-fed animals. Plasma anti-rDer f2 IgE, IgG1, IgG2a, and IgG2b levels were not changed by feeding with rDer f2. We conclude that recombinant Der f2 exhibits both sensitizing and hyposensitizing activities in mice. rDer f2 may be useful in immunotherapy and diagnosis of house-dust mite allergy. 相似文献
162.
Surface treatment using alkaline solutions was attempted to enhance the surface hydrophilicity and enzymatic hydrolyzability of hydrophobic poly(L ‐lactide) [ie poly(L ‐lactic acid) (PLLA) and poly(ε‐caprolactone) (PCL). The alkaline treatment was performed by immersing the PLLA and PCL films in 0.01 and 4 N NaOH solutions, respectively, for various periods of time. The effects of the alkaline treatment on the hydrophilicity of the films were monitored by dynamic contact angle measurements, while the enzymatic hydrolyzability of the PLLA and PCL films after the alkaline treatment were evaluated by weight losses in the presence of proteinase K and Rhizopus arrhizus lipase, respectively. With the alkaline treatment the hydrophilicity of the PLLA and PCL films was controllable in the advancing contact angle (θa) ranges of 84–108° and of 69–93°, respectively, by varying the alkaline treatment time. The enzymatic hydrolysis rates of the PLLA films became higher with decrease of the θa, irrespective of the crystallinity, strongly suggesting that the surface hydrophilicity or the surface molecular weight is crucial to determine their enzymatic hydrolyzability. In contrast, the enzymatic hydrolyzability of the PCL films remained unchanged even when the θa decreased from 93° to 73° by alkaline treatment for 4 h. However, prolonged alkaline treatment for periods of time exceeding 4 h, which insignificantly altered the θa but caused the formation of pores and cracks on the PCL film surface, accelerated the enzymatic hydrolysis of the PCL films. This indicates that the enzymatic hydrolyzability of the PCL film depends on the surface area per unit weight rather than the surface hydrophilicity. Copyright © 2003 Society of Chemical Industry 相似文献
163.
Many complex patterns are produced by the spatial prisoner’s dilemma, such as spatial games (Nature 1992;359:826–829) and
spatial strategies (Artif Life Robotics 2004;9:139–143). We have studied the inverse problem of identifying a game by estimating
the parameters in the payoff of the game from spatiotemporal patterns. 相似文献
164.
A two-dimensional computer simulation method, developed by the authors using the method of finite differences, was applied to estimate the cake growth in slip casting of alumina with a triangular gypsum mold and a box-type gypsum mold with a convex bottom. The cake growth patterns, water penetration patterns, water flow rate distributions, and pressure distributions were simulated in the molds and/or cakes. The simulated cake growth patterns were in good agreement with those observed experimentally in both molds. Moreover, the cake growths could be well understood from the results of the water flow rate distributions in each case. The present method is applicable to cake growth simulation in slip casting with complicated-shape gypsum molds. 相似文献
165.
Naotsugu Itoh Takuya Machida Wei-Chun Xu Hisamichi Kimura Tsuyoshi Masumoto 《Catalysis Today》1995,25(3-4):241-247
Amorphous PdxSi1-x(x=0.8,0.825,0.85) in the form of ribbon was prepared by a single-roller melt spinning technique to examine hydrogen permeability and catalytic activity for dehydrogenation. As a result, it was found that the amorphous specimens had higher tenacity and higher permeability of hydrogen than its crystallized form. Also, the surface of the amorphous specimen showed a catalytic activity for dehydrogenation of cyclohexane, while no activity was observed in the untreated. Taking advantage of both hydrogen permeability and catalytic activity, the amorphous PdxSi1-x would be expected to be a candidate for a catalytic membrane. 相似文献
166.
T Mano K Iwase R Hayashi N Hayakawa K Uchimura M Makino M Nagata Y Sawai N Oda M Hamada T Aono A Nakai A Nagasaka M Itoh 《Canadian Metallurgical Quarterly》1998,315(4):230-232
Chylous fistula complicates 1.1% of all radical neck dissections, and 2.4% of left-sided dissections. The standard treatment of established chylous leak in the reported cases is a pressure dressing applied to the lower neck. Here we present a case of chylous fistula, where conservative methods failed to cope with this complication. The additional application of a fibrin adhesive set was a successful modality of treatment. 相似文献
167.
K Murata R Matsuo T Manabe Y Tsujita M Tanaka J Oda K Kioka K Sou T Inoue 《Canadian Metallurgical Quarterly》1996,56(13):940-947
MRI was performed in 13 patients who had microwave coagulation therapy (MCT) for hepatocellular carcinoma. Six of them underwent surgery after MRI. The area (including tumor) treated by MCT showed low to high intensity on T1WI, and low to isointensity on T2WI. No enhancement was obtained on dynamic MRI. Histologically, this area was supposed to be coagulation necrosis. On T1WI, only tumor showed high intensity within the MCT area in 8 patients, and nearly uniform intensity was observed in 5 patients. Histologically, residual cell nuclei were observed in the former, and nearly uniform coagulation necrosis in the latter. The marginal part of the MCT area exhibited low intensity on T1WI, and high intensity on T2WI. Strong enhancement was obtained on dynamic MRI, and histologically, granulation tissue was noted. In the hepatic parenchyma around the MCT area, a ring-or wedge-shaped high intensity part was observed in 7 patients on T2WI, and that part was enhanced on dynamic MRI. This finding was considered to reflect changes such as hepatic hyperperfusion. In terms of the capability of visualizing residual tumor after MCT, MRI was superior to CT. Furthermore, a clear distinction was seen between the MCT area and non-MCT area on T2WI and dynamic MRI. Thus, MRI was useful in the determination of additional therapy. 相似文献
168.
To realize practical wavelength division multiplexing (WDM) systems, a high-performance N×N wavelength multiplexer is introduced that is based on an arrayed-waveguide grating. Its transmission characteristics are theoretically derived and experimentally confirmed. A prototype is constructed using the previously proposed techniques that attain low insertion loss and polarization independent operation. It has 16 channels (N=16) with a spacing of 0.8 mn, or 100 GHz, in the 1.55-μm band. Frequency relation between input and output ports, free spectral range, and passband width are determined. A demonstration of IM-DD pulse transmission shows that there is no degradation of bit error rate resulting from the finite passband width and crosstalk of the multiplexer. It is confirmed that the multiplexer can realize highly reliable N-channel WDM and WDM-based N×N interconnect optical networks 相似文献
169.
N Iwasaki N Oda M Ogata M Hara Y Hinokio Y Oda K Yamagata S Kanematsu H Ohgawara Y Omori GI Bell 《Canadian Metallurgical Quarterly》1997,46(9):1504-1508
Recent studies have shown that mutations in the hepatocyte nuclear factor (HNF)-1alpha gene are the cause of maturity-onset diabetes of the young type 3 (MODY3). We have screened 193 unrelated Japanese subjects with NIDDM for mutations in this gene: 83 with early-onset NIDDM (diagnosis at <30 years of age) and 110 with late-onset NIDDM (diagnosis > or = 30 years of age). All of the members of the latter group also had at least one sibling with NIDDM. The 10 exons, flanking introns, and promoter region were amplified using polymerase chain reaction and were sequenced directly. Mutations were found in 7 of the 83 (8%) unrelated subjects with early-onset NIDDM. The mutations were each different and included four missense mutations (L12H, R131Q, K205Q, and R263C) and three frameshift mutations (P379fsdelCT, T392fsdelA, and L584S585fsinsTC). One of the 110 subjects with late-onset NIDDM was heterozygous for the missense mutation G191D. This subject, who was diagnosed with NIDDM at 64 years of age, also had a brother with NIDDM (age at diagnosis, 54 years) who carried the same mutation, suggesting that this mutation contributed to the development of NIDDM in these two siblings. None of these mutations were present in 50 unrelated subjects with normal glucose tolerance (100 normal chromosomes). Mutations in the HNF-1alpha gene occur in Japanese subjects with NIDDM and appear to be an important cause of early-onset NIDDM in this population. In addition, they are present in about 1% of subjects with late-onset NIDDM. 相似文献
170.
Multi-scale structure of clustering particles 总被引:1,自引:0,他引:1
Spatial scale characteristics of particle clusters are investigated by using the flow field data obtained from time-dependent three-dimensional numerical simulations. Eulerian/Lagrangian approach with two-way coupling is adopted and individual particle-particle collisions are taken into account by using the hard-sphere deterministic model. More than sixteen million particles are tracked in the maximum case. The results show that the particle cluster consists of multiple-spatial scale components and a low wave number, hence the large-scale structure, is dominant. Three-dimensional structure reconstructed from the low-pass filtered data enables us to investigate the essential dynamics of particle clusters in detail. From the domain size-dependency study, it is found that the structure of particle cluster is sensitive to the horizontal domain size when the periodic boundary condition is used. 相似文献