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1.
Endoglucanase production was measured in culture filtrates of four species of Saccobolus growing in media containing glucose or crystalline cellulose as the only carbon sources. Enzyme activity was four to seven times higher in the presence of cellulose than glucose. S. saccoboloides showed maximal growth and enzyme production. The extracellular proteins secreted during growth on cellulose were separated by polyacrylamide gel electrophoresis and stained for proteins. A zymogram technique was used to visualize bands with endoglucanase activity. The four species showed different protein and isoenzyme patterns.  相似文献   
2.
T-cell-mediated autoimmune mechanisms are considered to be involved in the pathogenesis of primary biliary cirrhosis (PBC). In the previous study, we identified the immunodominant T-cell epitope on the E2 component of pyruvate dehydrogenase complex (PDC-E2) in patients with PBC who have HLA-DRB4*0101. In this report, we revealed that the frequency of the T cells reactive to the human PDC-E2 163-176 peptide is significantly increased in the peripheral blood of patients with PBC as compared with healthy subjects. We also confirmed that these T cells were all restricted with HLA-DRB4*01 (DR53) by using HLA-DR-transfected L cells. These results together with the evidence that the immunodominant B-cell epitope overlaps with the human T-cell epitope of the PDC-E2 antigen indicate that the T cells reactive to this epitope are closely associated with the pathogenesis of PBC at least in patients who have HLA-DR53. Therefore, we analyzed the T-cell receptor (TCR) Vbeta sequence of the five different T-cell clones and the three T-cell clones derived from three patients with PBC and healthy subjects, respectively, which are reactive to the human PDC-E2 163-176 peptide in the context of HLA-DR53. The Vbeta- and the Jbeta-gene usages were diverse among the T-cell clones (Vbeta11-Jbeta1.4, Vbeta8-Jbeta1.2, Vbeta12-Jbeta2.1, Vbeta10-Jbeta1.5, and Vbeta20-Jbeta2.1) in patients with PBC. By contrast, in the third complementarity determining region (CDR3), G was frequently found and GXG or GXS motif was identified in all T-cell clones. Moreover, RGXG motif was found in three clones generated from two patients. In healthy subjects, the Vbeta- and the Jbeta-gene usages were also diverse, and GXG and RGXG motif were found. These results indicate that the T cells may recognize the ligand (the human PDC-E2 163-176 peptide/HLA-DR53 complex) using the limited motif in the CDR3 region and that the design of CDR3-specific immunotherapy would be possible using these motifs.  相似文献   
3.
Pulmonary sequestration is a relatively rare anomaly. The arterial supply usually is derived from the aorta or its major branches. We present a 65-year-old female patient with pulmonary sequestration receiving arterial supply from the right coronary artery, complicated with sick sinus syndrome.  相似文献   
4.
The x-ray properties of multinested thin-foil mirror x-ray telescopes (XRT's) on board ASCA, the Advanced Satellite for Cosmology and Astrophysics, were fully evaluated with an x-ray pencil beam.Scanning over the telescope aperture of 35 cm in diameter with an x-ray pencil beam, we found the effective area of a set of XRT's to be 325, 200, and 113 cm(2) at energies of 1.5, 4.5, and 8.0 keV, respectively. We derive the point-spread functions (PSF's) of the XRT's by measuring the image profile at the focal plane with an x-ray CCD. The PSF is found to exhibit a sharp core concentrated within 30 arcsec and a broad wing extended to 3 arcmin in half-power diameter. We also evaluate the contribution of stray light, which is caused by the single reflection of x rays by primary or secondary mirrors and by the backside reflection of the mirrors. To obtain the characteristics of the XRT in the energy region of 0.5-10.0 keV, incorporated with the measurements at discrete energies, we develop a ray-tracing method with the telescope design parameter, the PSF, and optical constants. In particular, we obtain the optical constants around the gold-atom M shell (Au-M) absorption-edge energies by measuring the reflectivity of our mirror sample, with monochromatized x-rays in the energy range of 2.0-3.5 keV from synchrotron radiation. Taking into account the PSF's and optical constants, we find that our ray-tracing program can reproduce all these XRT performances.  相似文献   
5.
We developed a dual-probe (DP) atomic force microscopy (AFM) system that has two independently controlled probes. The deflection of each cantilever is measured by the optical beam deflection (OBD) method. In order to keep a large space over the two probes for an objective lens with a large numerical aperture, we employed the OBD sensors with obliquely incident laser beams. In this paper, we describe the details of our developed DP-AFM system, including analysis of the sensitivity of the OBD sensor for detection of the cantilever deflection. We also describe a method to eliminate the crosstalk caused by the vertical translation of the cantilever. In addition, we demonstrate simultaneous topographic imaging of a test sample by the two probes and surface potential measurement on an α-sexithiophene (α-6T) thin film by one probe while electrical charges were injected by the other probe.  相似文献   
6.
We report on a new photon-counting detector possessing unprecedented spatial resolution and moderate spectral resolution for 0.1-100 keV X-rays. It consists of an X-ray charge-coupled device (CCD) and a scintillator. The scintillator is directly coupled to the back surface of the X-ray CCD. Low-energy X-rays below 10 keV can be directly detected by the CCD. The majority of hard X-rays above 10 keV pass through the CCD but can be absorbed by the scintillator, generating visible photons. We coupled needlelike CsI(Tl) on the front surface of the back-illuminated (BI) CCD. The high detection efficiency of BI CCDs in the visible band enables us to collect visible photons emitted from the CsI(Tl) efficiently, leading to the moderate spectral resolution of 28.4% at 22.1 keV and 25% at 59.5 keV. We also investigated the imaging capability of our device and demonstrated high resolution imaging with an accuracy of 10 /spl plusmn/3 /spl mu/m at 17.4 keV.  相似文献   
7.
The surfaces of the aluminum foams were modified by the friction surface modification (FSM) process. The aluminum foams with a new surface structure were successfully obtained by the FSM process. The surface-modified zone (SMZ) had smoother surface than the unprocessed zone (UZ). A very dense layer without the cell structure was formed near the surface of the SMZ. The SMZ exhibited more high indentation strength than the UZ. Especially for 1390 rpm, the indentation strength was about twice the value of the UZ. The FSM process was a very effective technology for the improvement in the mechanical properties as well as the surface morphology of the porous metals. And then, the tool rotation speed was a very important parameter in order to control in the characteristics of the friction-surface-modified porous metals.  相似文献   
8.
The white-rot basidiomycete Pleurotus ostreatus produced sweet flavor compounds on a liquid medium. The major and minor compounds identified by GC-MS analysis were p-anisaldehyde (4-methoxybenzaldehyde) and 3-chloro-p-anisaldehyde (3-chloro-4-methoxybenzaldehyde), respectively. p-Anisaldehyde was only produced under static culture conditions. Differences in the type and quantity of flavor compounds produced among wild strains of P. ostreatus were observed. Aryl alcohol oxidase and manganese peroxidase activities increased parallel to the production of p-anisaldehyde. These results indicated that the biosynthesis of p-anisaldehyde is concerned in generating H2O2-activated peroxidase in the lignin-degradation system. Addition of L-tyrosine to the culture led to higher production of p-anisaldehyde. The flavor extract, which contains p-anisaldehyde, exhibited antimicrobial activity against Bacillus subtilis, Pseudomonas aeruginosa, Aspergillus niger and Fusarium oxysporum.  相似文献   
9.
Di-D-fructofuranose-1,2':2,3'-dianhydride (DFA III) was shown to enhance Ca absorption in rat and human intestine. The effects of DFA III administration (9 g per day for 4 weeks that corresponded to 3-fold the optimal dosage of DFA III) on human intestinal microbiota were studied using denaturing gradient gel electrophoresis (DGGE). The major groups of human intestinal microbiota reported previously: the Bacteroides, the Clostridium coccoides group (Clostridium cluster XIVa), the Clostridium leptum group (Clostridium cluster IV), and the Bifidobacterium group were detected. The similarity of 30 DGGE profiles based on the V3 region (before and after administration to the 15 subjects) of the 16S rDNA were calculated using Pearson's correlation based on numbers, positions and intensity of bands, and then a dendrogram of DGGE profiles was constructed by the unweighted pair group method using arithmetic average (UPGMA) clustering method. By these analyses, no difference in DGGE profiles after DFA III administration was observed in healthy subjects, while two subjects with chronic constipation showed different profiles, namely on numbers, positions and the intensity of some bands. Their stools were softer and stool frequencies increased and they obtained relief from constipation.  相似文献   
10.
The authors report here experimental results relating X-ray interaction location and event splitting. The X-ray interaction location can be localized at subpixel scale using the mesh technique. The authors found that the center of gravity of the split event is well-correlated with the X-ray interaction location. They analyzed the data using two models for the charge cloud shape: one is the rectangular model and the other is the Gaussian model. Although the authors could not distinguish between these models, they measured a root mean square charge cloud size of 1 to 2 μm for X-rays of Y-L (1.9 keV), Ag-L (3.0 keV), and Ti-K (4.5 keV). When the X-rays enter near the pixel boundary, the charge splits into adjacent pixels, allowing determination of the X-ray interaction location with an accuracy of 1.5 to 2.2 μm. The authors, therefore, expect that the X-ray CCD can function as an X-ray imager with subpixel resolution, which will be especially useful in applications involving very high spatial resolution optics  相似文献   
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