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21.
Calvarial bone defect associated with a hugh neurofibroma in the region of the lambdoid suture was reported in a 42-year-old man with v. Recklinghausen's neurofibromatosis. An enlarging occipital tumor was first noted at age 4 similar to or approximately 5, and an operation was performed at age 12. Lambda defect was noted at that time, but the operative diagnosis was, apparently, "meningocele". Available literature was reviewed, and the significance of calvarial bone defect in the region of the lambdoid suture as a manifestation of v. Recklinghausen's disease was stressed. Lambda defect witn no sclerosing margin, particularly if associated with hypoplasia of the ipsilateral mastoid cells, has been known to represent the primary nature of the bone defect due to mesodermal dysplasia. In the present case, plain radiographs of the skull revealed abnormal sclerotic change around the bone defect. It is suggested that such an osteoblastic change may well indicate the secondary nature of the bone defect due to the presence of overlying neurogenic tumor.  相似文献   
22.
SiO2–TiO2 spherical microparticles of about 0.7 μm in diameter were prepared by the sol–gel method. Anatase nanocrystals were formed in the microparticles and their specific surface area was increased after a hot-water treatment at 90 °C. From the changes in the concentration of I2 photocatalytically generated from KI aqueous solution, the activity of the SiO2–TiO2 microparticles was found to increase with increasing the hot-water treatment time. Particulate, thick films were electrophoretically deposited on indium tin oxide (ITO)-coated glass substrates using the anatase nanocrystal-precipitated SiO2–TiO2 microparticles. The thickness of the electrophoretically deposited particulate film increased to be approximately 10 μm with an increase in applied voltage. The resultant thick film showed a high photocatalytic activity.  相似文献   
23.
24.
The impact of radiation damage on the device performance of 4H-SiC Schottky diodes, which are irradiated at room temperature with 2-MeV electrons is studied. After irradiation the reverse current increases, while the forward current and the capacitance decrease with barrier height and carrier density. The decrease of the barrier height is mainly responsible for the increase of the reverse current, while the decrease of the forward current for a high fluence is caused by the increase of the resistance in the bulk of the crystal. Although no electron capture levels are observed before irradiation, three electron capture levels (E1, E2, and E3) are induced after irradiation. It is noted that the decrease in carrier density is partly caused by the contribution of non-observed electron capture level in the DLT spectrum, which compensates the free carriers.  相似文献   
25.
Rats (8 wk of age) fed a conventional diet were shifted to diets containing 10% Oenothera biennis Linn oil (OBLO, linoleic acid + gamma-linolenic acid) from a wild plant, evening primrose oil (EPO, linoleic acid + gamma-linolenic acid) from a cultivated plant, bio-gamma-linolenic acid oil from mold (BIO, palmitic acid + oleic acid + linoleic acid + gamma-linolenic acid), safflower oil (linoleic acid), palm oil (PLO, palmitic acid + oleic acid + linoleic acid), or soybean oil (linoleic acid + alpha-linolenic acid) with 0.5% cholesterol for 13 wk. Though there were no significant differences in the food intake among the groups, the body weight gain of the OBLO group was significantly lower than that of the other groups except for the BIO and PLO groups, and that of the EPO and SBO groups were the highest among the groups. The liver weight of the OBLO group was significantly lower than that of other groups, and that of the PLO group was the highest among the groups. The serum total cholesterol and very low density lipoprotein (VLDL) + intermediate density lipoprotein (IDL) + low density lipoprotein (LDL) cholesterol concentrations of the OBLO and EPO groups were consistently lower than those in the other groups. However, those of the BIO group were higher than those in the OBLO and EPO groups. The liver cholesterol concentration of the PLO group was the highest among all groups except for the EPO group. The fecal neutral sterol and bile acid extraction of the BIO group tended to increase compared to the other groups. The results of this study demonstrate that OBLO and EPO inhibit the increasing of serum total cholesterol and VLDL + IDL + LDL-cholesterol concentrations in the presence of excess cholesterol in the diet compared with the other dietary oils.  相似文献   
26.
The present study is concerned with the sulfidation treatment of copper-containing plating sludge towards copper resource recovery by flotation of copper sulfide from treated sludge. The sulfidation treatment was carried out by contacting simulated or real copper plating sludge with Na(2)S solution for a period of 5 min to 24 h. The initial molar ratio of S(2-) to Cu(2+) (S(2-) to Me(2+) in the case of real sludge) was adjusted to 1.00, 1.25 or 1.50, while the solid to liquid ratio was set at 1:50. As a result, it was found that copper compounds were converted to various copper sulfides within the first 5 min. In the case of simulated copper sludge, CuS was identified as the main sulfidation product at the molar ratio of S(2-) to Cu(2+) of 1.00, while Cu(7)S(4) (Roxbyite) was mainly found at the molar ratios of S(2-) to Cu(2+) of 1.50 and 1.25. Based on the measurements of oxidation-reduction potential, the formation of either CuS or Cu(7)S(4) at different S(2-) to Cu(2+) molar ratios was attributed to the changes in the oxidation-reduction potential. By contrast, in the case of sulfidation treatment of real copper sludge, CuS was predominantly formed, irrespective of S(2-) to Me(2+) molar ratio.  相似文献   
27.
Abstract:  As an improvement of the intensity correlation used widely in conventional electronic speckle photography, we propose a new technique for displacement measurement based on correlating Stokes-like parameters derivatives for transformed speckle patterns. The method is based on a Riesz transform of the intensity speckle pattern, which converts the original real-valued signal into a complex signal. In closest analogy to the polarisation of a vector wave, the Stokes-like vector constructed from the spatial derivative of the generated complex signal has been applied for correlation. Experimental results are presented that demonstrate the validity and advantage of the proposed pseudo-Stokes vector correlation technique over conventional intensity correlation technique.  相似文献   
28.
Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs.  相似文献   
29.
SLC25A39/40, involved in mitochondrial GSH (mGSH) import from the cytoplasm, is essential for protection against oxidative stress and mitochondrial dysfunction. We examined the effects of cholestasis, through bile duct ligation (BDL) and lipopolysaccharide (LPS)-induced inflammation in mice, on Slc25a39/40 expression. Additionally, we used human clear cell renal carcinoma (KMRC-1) cells to elucidate the mechanism of regulation of SLC25A39/40 expression in the kidneys after LPS treatment. BDL resulted in a decrease in Slc25a39 mRNA in the liver and a decrease in Slc25a39/40 mRNA and protein in the kidneys. Consequently, there was a significant decrease in mGSH levels in the kidneys of BDL mice compared with those in sham mice. LPS treatment resulted in increased Slc25a40 expression in the kidneys. In KMRC-1 cells, the combination treatment of LPS-RS or FPS-ZM1 with LPS suppressed the LPS-induced increase in SLC25A40, suggesting that SLC25A40 expression could be regulated by the signaling pathway via toll-like receptor 4 and the receptor for advanced glycation end products, respectively. Our findings contribute to understanding the role of mGSH in the maintenance of the mitochondrial redox state. To the best of our knowledge, this is the first study that demonstrates the changes in Slc25a39/40 expression in mice with cholestasis-associated renal injury and LPS-induced inflammation.  相似文献   
30.
Aberrant glycosylation of IgA1 is involved in the development of IgA nephropathy (IgAN). There are many reports of IgAN markers focusing on the glycoform of IgA1. None have been clinically applied as a routine test. In this study, we established an automated sandwich immunoassay system for detecting aberrant glycosylated IgA1, using Wisteria floribunda agglutinin (WFA) and anti-IgA1 monoclonal antibody. The diagnostic performance as an IgAN marker was evaluated. The usefulness of WFA for immunoassays was investigated by lectin microarray. A reliable standard for quantitative immunoassay measurements was designed by modifying a purified IgA1 substrate. A validation study using multiple serum specimens was performed using the established WFA-antibody sandwich automated immunoassay. Lectin microarray results showed that WFA specifically recognized N-glycans of agglutinated IgA1 in IgAN patients. The constructed IgA1 standard exhibited a wide dynamic range and high reactivity. In the validation study, serum WFA-reactive IgA1 (WFA+-IgA1) differed significantly between healthy control subjects and IgAN patients. The findings indicate that WFA is a suitable lectin that specifically targets abnormal agglutinated IgA1 in serum. We also describe an automated immunoassay system for detecting WFA+-IgA1, focusing on N-glycans.  相似文献   
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