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71.
We examined a method to produce bread from crystalline rice flour without using thickening agents such as gluten, polysaccharide thickening, and amorphous rice flour. Rice grains were pulverized by a jet mill to produce flour. Samples of rice flours of various particle size distributions were prepared by using a size shifter. The degree of starch damage and the dynamic viscoelasticity of rice batter were measured in this work. We also baked bread of the flour of each size distribution to study processability for making bread. The batter made by the pulverized flour of rice particle size ranging from 75 to 106 μm had the highest expansion ratio and a good processability for baking breads compared to other particle size batters. The rice bread with high expansion ratio was produced by controlling particle size of crystalline rice flour without using thickening agents.  相似文献   
72.
To reduce the cost and time required to routinely perform the genetically modified organism (GMO) test, we developed a duplex quantitative real-time PCR method for a screening analysis simultaneously targeting an event-specific segment for GA21 and Cauliflower Mosaic Virus 35S promoter (P35S) segment [Oguchi et al., J. Food Hyg. Soc. Japan, 50, 117-125 (2009)]. To confirm the validity of the method, an interlaboratory collaborative study was conducted. In the collaborative study, conversion factors (Cfs), which are required to calculate the GMO amount (%), were first determined for two real-time PCR instruments, the ABI PRISM 7900HT and the ABI PRISM 7500. A blind test was then conducted. The limit of quantitation for both GA21 and P35S was estimated to be 0.5% or less. The trueness and precision were evaluated as the bias and reproducibility of the relative standard deviation (RSD(R)). The determined bias and RSD(R) were each less than 25%. We believe the developed method would be useful for the practical screening analysis of GM maize.  相似文献   
73.
The partition of divalent cobalt, copper, zinc and cadmium between hydrochloric acid solutions and solutions of tri-n-butyl phosphate (TBP) in benzene or kerosene has been investigated under different conditions. Further the absorption spectra of both the aqueous and organic phases have been studied, and the infrared spectra of the organic phases have been examined. It was found that the order of the extraction efficiency of TBP for divalent metalsis Zu > Cd > Cu > Co for [HCl]aq < 8M and Zn > Cd > Co > Cu for [HCl]aq > 8M.  相似文献   
74.
The distribution equilibria of hydrochloric, nitric, perchloric, sulphuric and phosphoric acids between aqueous solutions and a solution of tricaprylmethyl-ammonium chloride in organic solvent have been investigated. The organic phases have been studied by infra-red and nuclear magnetic resonance spectroscopy. As a result, it is found that at low aqueous acidity the extraction of these acids is governed by the ion exchange reaction, forming the mono-quaternary ammonium salts of monobasic acids and the mono-, di- (and tri-) quaternary ammonium salts of di- (and tri-) basic acids, and at higher acidity by the formation of the adducts to quaternary ammonium salts with additional acids.  相似文献   
75.
In the last decade, dielectric barrier discharge (DBD) plasma actuators using a combination voltage of AC and a nanosecond pulse have been studied. The combined‐voltage‐driven plasma actuator increases the body force effect, including wall jet and flow suction, by overlapping the nanosecond pulse voltage, while the DBD plasma actuator driven by nanosecond pulses is a flow control actuator generating compression waves due to pulse heating, which makes it possible to supply an active flow control at a high‐speed flow, reported as up to Mach 0.7. In this study, a DBD plasma actuator driven by a combination voltage of sinusoidal AC and nanosecond pulse was experimentally investigated. The time‐averaged net thrust and cycle‐averaged power consumption of the actuator were characterized by using an electrical weight balance and the charge‐voltage cycle of a DBD plasma actuator, respectively. The plasma actuator thrust driven with the combination voltage showed increased thrust with increasing pulse repetition rate. The energy consumption of the actuator was controlled by varying the AC phase when the nanosecond pulse was applied. Therefore, the thrust and power consumption in the actuator were almost independently controlled by the pulse repetition rate and the pulse imposed phase.  相似文献   
76.
Currently, pyripyropene A, which is isolated from the culture broth of Aspergillus fumigatus FO‐1289, is the only compound known to strongly and selectively inhibit the isozyme sterol O‐acyltransferase 2 (SOAT2). To aid in the development of new cholesterol‐lowering or anti‐atherosclerotic agents, new A‐ring simplified pyripyropene A analogues have been designed and synthesized based on total synthesis, and the results of structure–activity relationship studies of pyripyropene A. Among the analogues, two A‐ring simplified pyripyropene A analogues exhibited equally efficient SOAT2 inhibitory activity to that of natural pyripyropene A. These new analogues are the most potent and selective SOAT2 inhibitors to be used as synthetic compounds and attractive seed compounds for the development of drug for dyslipidemia, including atherosclerotic disease and steatosis.  相似文献   
77.
78.
Chimeric T84.66 (cT84.66) is a monoclonal antibody (mAb) of high specificity and affinity for the tumor-associated carcinoembryonic antigen (CEA). Radiolabeled cT84.66 has demonstrated utility in the clinic as a reagent for the radioimmunoscintigraphy and radioimmunotherapy of CEA-positive colorectal and breast malignancies. To extend the therapeutic efficacy of T84.66, humanization by complementary determining region (CDR) grafting was employed. CDR grafting is a well-established technique, though often a series of framework back-mutations is required to restore high affinity. Recently, the crystal structure of the T84.66 diabody (scFv dimer) derived from the murine T84.66 mAb was determined, facilitating the humanization process by the availability of crystal structure data for both the graft donor and graft acceptor. A search of the Protein Data Bank revealed close structural similarity (r.m.s.d. of 1.07 A) between the Fv of T84.66 and the Fv of 4D5v8, a humanized anti-p185HER2 antibody marketed as Herceptin (Trastuzumab). This resulted in two humanized versions of the T84.66 M5A and M5B mAbs that differed only in the number of murine residues present in the C-terminal half of CDR-H2. Biochemical analysis and animal biodistribution studies were conducted to evaluate the humanized mAbs. The M5A, M5B and cT84.66 mAbs showed sub-nanomolar affinity for CEA and as radiolabeled mAbs exhibited specific tumor localization in tumor bearing mice. The T84.66 M5A mAb was selected for clinical development due to a slightly higher tumor uptake and a larger content of human residues, and was renamed hT84.66. A limited-scale production and animal imaging study have demonstrated hT84.66's ability to support clinical trials. Planned clinical trials will determine the effective utilization of this structure-based approach in the development of a promising new therapeutic.  相似文献   
79.
An engineered anti-carcinoembryonic antigen (CEA) diabody (scFv dimer, 55 kDa) was previously constructed from the murine anti-CEA T84.66 antibody. Tumor targeting, imaging and biodistribution studies in nude mice bearing LS174T xenografts with radiolabeled anti-CEA diabody demonstrated rapid tumor uptake and fast blood clearance, which are favorable properties for an imaging agent. Current radiolabeling approaches result in random modification of the protein surface, which may impair immunoreactivity especially for smaller antibody fragments. Site-specific conjugation approaches can direct modifications to reactive groups located away from the binding site. Here, cysteine residues were introduced into the anti-CEA diabody at three different locations, to provide specific thiol groups for chemical modification. One version (with a C-terminal Gly-Gly-Cys) existed exclusively as a disulfide-bonded dimer. This cysteine-modified diabody (Cys-diabody) retained high binding to CEA and demonstrated tumor targeting and biodistribution properties identical to the non-covalent diabody. Furthermore, following reduction of the disulfide bond, the Cys-diabody could be chemically modified using a thiol-specific bifunctional chelating agent, for radiometal labeling. Thus, the Cys-diabody provides a covalently linked alternative to conventional diabodies, which can be reduced and modified site-specifically. This format will provide a versatile platform for targeting a variety of agents to CEA-positive tumors.  相似文献   
80.
T cell growth factor receptor, interleukin-2 receptor alpha chain (IL-2R alpha) is constitutively expressed on human T-cell leukemia virus type-1 (HTLV-1) infected T cells. We have established L cell lines which express both IL-2R alpha and the Rex protein of HTLV-1. We found that IL-1R alpha mRNA is stabilized in a cell line, Ltk/1-2a, which expresses a high amount of the Rex protein. In the presence of lower amounts of Rex, stabilization of the mRNA was not observed. These results may well explain the mechanism by which most of the lymphocytes infected with HTLV-1 escape from malignant transformation.  相似文献   
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