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71.
72.
This paper describes the measurement of a cylindrical surface with sinusoidal micro-structures over a large area on a diamond turning machine. The sinusoidal micro-structures, which are fabricated on the periphery surface of a cylinder by the fast tool servo-based diamond turning, are superposition of periodic sine-waves along the cylinder axis and the cylinder circumference with amplitudes of 100 nm and wavelengths of 100 μm, respectively. An optical two-dimensional (2D) slope sensor with a multi-spot light beam is developed for measurement of the 2D local slopes of the sinusoidal micro-structured surface. A cylindrical lens is employed in the sensor for removing the influence of the curvature of the cylinder surface. Experiments of fabrication and measurement of the sinusoidal micro-structured surface on an ultra-precision diamond turning machine are carried out.  相似文献   
73.
The effect of a high extracellular glucose concentration on the mitogenic response of rat vascular smooth muscle cells (SMCs) to heparin-binding epidermal growth factor-like growth factor (HB-EGF) was investigated. The mitogenic effect of HB-EGF was significantly greater in SMCs cultured in high glucose (25 mmol/L) than in cells cultured in low glucose (5.5 mmol/L) or at high osmolarity (5.5 mmol/L glucose plus 19.5 mmol/L mannitol). The mitogenic effect of epidermal growth factor (EGF), which shares the EGF receptor with HB-EGF, was not affected by glucose concentration. The mitogenic effect of HB-EGF was greater when incubated with heparan sulfate (HS) isolated from SMCs cultured in high glucose than with HS from cells cultured in low glucose. HS synthesized by cells in high glucose was of smaller molecular size and less sulfated than HS synthesized by cells in low glucose. The abundance of mRNA encoding HS-N-deacetylase/N-sulfotransferase (HS-NdAc/NST), a regulatory enzyme in the biosynthesis of HS, was decreased by high glucose in a protein kinase C-independent manner. These observations suggest that the enhanced mitogenic response to HB-EGF in SMCs cultured in high glucose may be attributable to changes in cell-associated HS. Downregulation of HS-NdAc/NST gene expression by high glucose may be related to the altered HS biosynthesis.  相似文献   
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75.
This study was carried out to determine the chemical composition, cholesterol contents and fatty acids profile of Brazilian commercial chicken giblets. The analysis were performed in gizzard, liver and heart in natura and also in cooked gizzard, fried liver and roasted heart. Fat and cholesterol contents ranged from 0.88% and 72.68 mg/100 g, in cooked gizzard, to 22.19% and 213.18 mg/100 g, in roasted heart. As the fat content gets higher, so does the cholesterol content. Palmitic (C16:0) and stearic acids (C18:0) were the predominant saturated fatty acids (SFA). The C16:0 ranged from 6.39% in cooked gizzard to 18.51% in fried liver. The C18:0 level ranged from 6.62% in roasted heart to 19.19% in cooked gizzard. Linoleic acid (C18:2 omega 6) was the predominant polyunsaturated fatty acid (PUFA). The data revealed that the three different analysed giblets presented a good PUFA/SFA ratio, with values of 1.11, 1.14 and 1.40 for cooked gizzard, fried liver and roasted heart, respectively.  相似文献   
76.
The breakup of non-Newtonian emulsion jets into drops was experimentally studied by ejecting both O/W and W/O emulsions vertically downward into stagnant air through nozzles. Breakup lengths of non-Newtonian emulsion jets were found to be almost equivalent to those of Newtonian jets. Experimental breakup data establish that the static surface tension of the oil phase can be used as the surface tension of W/O emulsion jets, whereas the dynamic surface tension of aqueous surfactant solutions is used as that of O/W emulsion jets. Diameters of drops formed from non-Newtonian emulsion jets are in good agreement with the prediction from the stability theory previously developed by the authors. When the rheological index in a power law model is appreciably smaller than unity and the Ohnesorge number is significantly large, however, drop sizes are larger than the prediction because of the profile relaxation in jets. The critical velocity of emulsion jets, either O/W or W/O emulsion, is significantly lower than that of homogeneous Newtonian jets.  相似文献   
77.
A new catalyst, ruthenium-tin-alumina is found to selectively hydrogenate oleic acid to 9-octadecen-1-ol (oleyl + elaidyl alcohol) at low pressure with high yield. Catalyst preparation methods, catalyst raw materials and activation conditions have a significant effect on the activity of the catalyst. The optimum atomic ratio of ruthenium to tin is about 1:2. Catalyst prepared by an improved sol-gel method shows higher activity and selectivity than catalysts prepared by impregnation and coprecipitation methods. Chloride is found to have a negative effect on catalytic activity. The best catalyst is prepared from chloride-free ruthenium and tin raw materials. Under the optimum reaction conditions of 250°C and 5.6 MPa, the selectivities for 9-octadecen-1-ol and total alcohol (9-octadecen-1-ol + stearyl alcohol) formation are 80.9% and 97%, respectively, at a conversion of 81.3%.  相似文献   
78.
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases.  相似文献   
79.
Periodontal inflammation is a common inflammatory disease associated with chronic inflammation that can ultimately lead to alveolar attachment loss and bone destruction. Understanding autophagy and pyroptosis has suggested their significant roles in inflammation. In recent years, studies of differentiated embryo-chondrocyte expressed genes 1 and 2 (Dec1 and Dec2) have shown that they play important functions in autophagy and in pyroptosis, which contribute to the onset of periodontal inflammation. In this review, we summarize recent studies on the roles of clock genes, including Dec1 and Dec2, that are related to periodontal inflammation and other diseases.  相似文献   
80.
Certain foodstuffs exhibit matrix interference effects on the vitamin B1 analysis prescribed in the official methods of the European Union, AOAC International, and Japan. In this study, we demonstrated that one of the problematic polyphenols in green tea or cocoa was tannin. For these matrices, thiamine was found to interact with tannin in the extraction step and was thus removed by filtration as a residue. To resolve the matrix interference, we proposed lowering the pH of the extraction solution by adding hydrochloric acid after the enzyme reaction. High precision (2–3% RSDr) and good recovery (98.3–103%) were obtained with reference materials using the proposed method. We also confirmed the equivalence of the obtained data from the proposed method and the Japanese official method for nutritional labeling. From these results, the method was found to be effective for vitamin B1 analysis regardless of the presence of interference matrices.  相似文献   
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