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101.
The phenolic compositions of non-germinated/germinated seeds and seed sprouts (at 6–10 day-old) of common (Fagopyrum esculentum Möench) and tartary (Fagopyrum tataricum Gaertn.) buckwheats were investigated. Phenolic compounds, including chlorogenic acid, four C-glycosylflavones (orientin, isoorientin vitexin, isovitexin), rutin and quercetin, were determined in the seed sprouts by high-performance liquid chromatography (HPLC). In the edible parts of common buckwheat sprouts, individual phenolics significantly increased during sprout growth from 6 to 10 days after sowing (DAS), whereas in tartary buckwheat sprouts they did not. While the sum contents of phenolic compounds in the edible part (mean 24.4 mg/g DW at 6–10 DAS) of tartary buckwheat sprouts were similar to those of common buckwheat sprouts, rutin contents in the non-germinated/germinated seeds (mean 14.7 mg/g DW) and edible parts (mean 21.8 mg/g DW) of tartary buckwheat were 49- and 5-fold, respectively, higher than those of common buckwheat. Extracts of the edible parts of both species showed very similar free radical-scavenging activities (mean 1.7 μmol trolox eq/g DW), suggesting that the overall antioxidative activity might be affected by the combination of identified phenolics and unidentified (minor) components. Therefore, buckwheat seed sprouts are recommended for their high antioxidative activity, as well as being an excellent dietary source of phenolic compounds, particularly tartary buckwheat sprouts, being rich in rutin.  相似文献   
102.
三坐标测量机的空间曲面测量路径优化分析   总被引:6,自引:0,他引:6  
本文主要介绍了广泛应用于反求工程中的三坐标机的测量原理,并介绍了应用三坐标机进行测量时,几种曲面测量规划和测量路径优化的方法。最后例举了建筑安全帽的测量过程。  相似文献   
103.
Advanced glycation end products (AGEs) are produced in response to a high-glucose environment and oxidative stress and exacerbate various diseases. Nε-(Carboxymethyl)lysine (CML) is an AGE that is produced by the glycation of lysine residues of proteins. There are a few reports on alterations in protein function due to CML modification; however, its association with cancer is not clear. We investigated the significance of CML modification in high mobility group box protein-1 (HMGB1), a cytokine that is significantly associated with cancer progression. Treatment of the gastric cancer cell lines TMK1 and MKN74 with glyoxal or glucose resulted in increased CML modification compared to untreated cells. CML-HMGB1 was modified via oxidation and more pronouncedly activated the receptor for AGE and downstream AKT and NF-κB compared to naïve HMGB1 and oxidized HMGB1. CML-HMGB1 bound with reduced affinity to DNA and histone H3, resulting in enhanced extranuclear translocation and extracellular secretion. Treatment of gastric cancer cells with CML-HMGB1 enhanced cell proliferation and invasion, sphere formation, and protection from thapsigargin-induced apoptosis, and decreased 5-FU sensitivity in comparison to HMGB1. Further, CML-HMGB1 was detected at various levels in all the 10 gastric cancer tumor specimens. HMGB1 levels correlated with primary tumor progression and distant metastasis, whereas CML-HMGB1 levels were associated with primary tumor progression, lymph node metastasis, distant metastasis, and stage. In addition, CML-HMGB1 levels correlated with oxidative stress in cancer tissues and resistance to neoadjuvant therapy. Therefore, CML modification of HMGB1 enhanced the cancer-promoting effect of HMGB1. In this study, CML-HMGB1 has been highlighted as a new therapeutic target, and analysis of the molecular structure of CML-HMGB1 is desired in the future.  相似文献   
104.
ABSTRACT

At Japan Atomic Energy Agency (JAEA) MOX fuel facilities, a worker usually wears a protective lead apron; therefore, the dose to the lens of the eye (lens dose) outside the apron is higher than that to the torso. To estimate the potential impact on the current facility operation of the International Commission of Radiological Protection (ICRP)-proposed lens dose limit reduction from 150 mSv/y to average 20 mSv/y, the authors carried out an analysis on the past dose records for the workers over the last 18 years. Of a total of 4,312 workers’ records analyzed, two workers’ annual lens doses exceeded the lowered limit of 20 mSv (23.3 mSv and 20.7 mSv), although the maximum effective dose was below 10 mSv in each case. These compiled dose data reveal that in the glovebox and related operations the lens dose will be a limiting factor in radiological control under the newly lowered dose limit. To ensure that the number of workers with an annual lens dose greater than 15 mSv (approximately 0.6% of the workers) is kept to a minimum, the implementation of an administrative control level for the lens dose is considered.  相似文献   
105.
ABSTRACT

NMR( Nuclear Magnetic Resonance ) measurements were car ried out to study the molecular movement of CMPO and La(III)(NO3) 3? CMPO complex and the ligand-exchange reaction for Eu(III) and Gd(III)-CMPO systems. From the 13C relaxation time measurement of La(NO3) 3 3CMPO it was found that the T1 value for the isobutyl CH and CH2 carbons and the carbonyl carbon became considerably shorter on complexation, indicating that the carbonyl group participates in the bonding between CMPO and La3+ ion as well as the phosphoryl group. The numbers of CMPO molecules coordinated to Eu3+ and Gd3+ ions in CDCl3 solution were estimated to be 3 and 2, respectively, in the presence of excess CMPO. The activation parameters for the ligand-exchange reaction were evaluated to be ΔH* = 37.8±1.9[kJ/mol],ΔS* = -59.9±6.5[J/molk? K] and ΔH* = 41.3±1.6[kJ/mol], ΔS* = -44.1±5.3[J/mol-K] for Eu(III)-CMPO and Gd(III)-CMPO systems, respectively. The independence of the exchange rate constants on the concentration of CMPO indicates that these ligand-exchange reactions seem to proceed through either a dissociative ( D ) mechanism or an interchange dissociative ( Id ) mechanism characterized by a stability constant of outer-sphere complex( KQ ) ≥ 100.  相似文献   
106.
The human immunodeficiency virus type 1 (HIV‐1) uses CD4 and the co‐receptor CCR5 or CXCR4 in the process of cell entry. The negatively charged extracellular domains of CXCR4 (CXCR4‐ED) interact with positive charges on the V3 loop of gp120, facilitating binding via electrostatic interactions. The presence of highly conserved positively charged residues in the V3 loop suggests that CXCR4‐ED‐derived inhibitors might be broadly effective inhibitors. Synthetic peptide derivatives were evaluated for anti‐HIV‐1 activity. The 39‐mer extracellular N‐terminal region (NT) was divided into three fragments with 10‐mer overlapping sites ( N1 – N3 ), and these linear peptides were synthesized. Peptide N1 contains Met 1–Asp 20 and shows significant anti‐HIV‐1 activity. Extracellular loops 1 and 2 (ECL1 and 2) were mimicked by cyclic peptides C1 and C2 , which were synthesized by chemoselective cyclization. Cyclic peptides C1 and C2 show higher anti‐HIV‐1 activity than their linear peptide counterparts, L1 and L2 . The cytotoxicities of C1 and C2 are lower than those of L1 and L2 . These results indicate that Met 1–Asp 20 segments of the NT and cyclic peptides of ECL1 and ECL2 are potent anti‐HIV‐1 drug candidates.  相似文献   
107.
Fine particulate and phase pure barium titanate with its average particle size as small as 120 nm and its tetragonality as high as 1.0085 was obtained by adding bovine serum albumin (BSA) to the reactant mixture comprising fine particulate BaCO3 and TiO2. In the presence of BSA, BaCO3 decomposed at substantially lower temperatures as a consequence of coordination of BSA preferentially to the ligand field of Ba. Elimination of remaining free carbon by increasing oxygen partial pressure under flowing air was one of the technical key issues of the high crystallinity and sinterability of the product.  相似文献   
108.
109.
In the rainfall-runoff process, interaction between surface and subsurface flow components plays an important role, especially in rainwater abstraction and overland flow initiation at the early stage of rainfall events. Coupling of surface and subsurface flow submodels, therefore, is necessary for advanced comprehensive and sophisticated rainfall-runoff simulation. This article presents a conjunctive two-dimensional (2D) surface and three-dimensional (3D) subsurface flow model, which uses the noninertia approximation of the Saint-Venant equations for 2D unsteady surface flow and a modified version of the Richards equation for 3D unsteady unsaturated and saturated subsurface flows. The equations are written in the form of 2D and 3D heat diffusion equations, respectively, and solved numerically. The surface and subsurface flow components are coupled interactively using the common boundary condition of infiltration through the ground surface. The conjunctive model is verified with Smith and Woolhiser’s experimental data (reported in 1971) of initially dry and initially wet soil. Subsequently the model is applied to a hypothetical soil plot of clay or sand to simulate the overland flow, infiltration, and subsurface flow for four different rainfalls. The conjunctive model contributes as a tool for improved detailed simulation of 2D surface and 3D subsurface flows and their interaction.  相似文献   
110.
We compared the repellency and toxicity against adzuki bean beetles among six troponoid compounds, and examined the relationship between their structure and activity. γ-Thujaplicin showed the highest repellency against the beetles among the compounds tested, while the repellency of tropiliden was quite low. The results suggested that the keto and hydroxyl groups are important in the repellent properties of troponoid compounds. Although an isopropyl group was also important in repellency, the effect varied according to its position on the seven-member ring; the farther the isopropyl group was from the keto and hydroxyl groups, the higher the repellency became. As with its repellency effect, the toxicity of tropiliden was quite low. Tropone showed the highest toxicity among the compounds tested while its repellency was relatively low. Similar to its repellency, γ-thujaplicin showed the highest toxicity among the thujaplicins. However, the toxicities of α-thujaplicin and β-thujaplicin (hinokitiol) were similar, unlike the repellency. In summary, it appears that the toxicity of troponoid compounds does not always coincide with their repellency. Furthermore, the repellency and toxicity of a mixture of γ-thujaplicin and β-thujaplicin, whose production cost is cheaper than that of hinokitiol alone, were investigated. The mixture strongly repelled the adzuki bean beetles. We conclude that the mixture of γ-thujaplicin and β-thujaplicin is a promising repellent.  相似文献   
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