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991.
Hatakeyama E Kajita H Sugawara T Sasaki A Takahashi S Komukai T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2006,47(4):137-145
A method for simultaneous determination of multiple pesticide residues in agricultural products was developed by using a pretreatment with ultrafiltration, followed by liquid chromatography-tandem mass spectrometry (LC/MS/MS). The pretreatment process (extraction of pesticides from agricultural products with methanol, dilution of the extract with water, and ultrafiltration) gave recoveries in the range of 50-150% for 63 of 83 pesticides spiked at 0.25 microg/ g into 6 agricultural products. The detection limits of pesticides by LC/MS/MS were below 0.0005-0.05 micro/g. This method is useful for screening purposes and for multiresidue analysis of pesticides in agricultural products. Pesticide residues in 50 domestic crops were investigated by this method, and residues of 14 pesticides were detected in 30 crops. 相似文献
992.
993.
To treat autoimmune diseases, it is important to identify which peptides bind to major histocompatibility complex (MHC) class II molecules (HLA-DRs). Predicting the peptides that bind to MHC class II molecules can effectively reduce the number of experiments required for identifying helper T cell epitopes. In our previous study, we applied fuzzy neural networks (FNNs) to solve this problem. However, an FNN requires a long calculation time and a large number of peptides; this means performing several experiments. In this study, we applied a boosted fuzzy classifier with the SWEEP operator method (BFCS) to solve this problem. For comparison, two other conventional modeling methods, namely, support vector machine and FNN combined with the SWEEP operator method (FNN-SWEEP) instead of using solely an FNN, were employed. Compared with FNN, FNN-SWEEP is extremely fast and has an almost identical prediction accuracy. The model constructed by BFCS showed an accuracy approximately 5%-10% higher than that constructed by FNN-SWEEP. In addition, BFCS was 30,000-120,000 times faster than FNN-SWEEP. This result suggests that BFCS has the potential to function as a new method of predicting peptides that bind to various protein receptors. 相似文献
994.
Tojo Y Syou R Yoshida M Momose J Ginya H Takahashi M Tajima H Yohda M 《Journal of Bioscience and Bioengineering》2006,102(5):474-477
A single-nucleotide-polymorphism-typing method using a novel three-dimensional DNA microarray, Bio-Strand, is promising because it is rapid, inexpensive and easily automated. It has been developed with the intent to overcome the drawbacks of conventional DNA microarrays, which use flat surfaces and impermeable materials such as glass slides; Bio-Strand as a novel DNA microarray, with its permeability, has a significantly improved stability compared with conventional DNA microarrays that use impermeable materials. In this study, we have developed a simple method of pretreating a polyamide monofilament to increase its surface area and to make it permeable, which makes Bio-Strand more sensitive and stable, allowing it to be adapted for clinical diagnostic applications. The fluorescence signal obtained with a nylon 6 monofilament pretreated under optimal conditions (hydrolysis by 5 M HCl/ethanol followed by washing with 50% ethanol and 100% ethanol) was significantly stronger than that obtained with an untreated monofilament. 相似文献
995.
A newly developed real-time PCR assay rapidly quantifies the total bacterial numbers in contaminated ready-to-eat vegetables and fruits compared with the standard plate count method. Primers targeting the rpoB gene, which encodes for the beta subunit of the bacterial RNA polymerase and which is common to most bacterial species, was used instead of the 16S rRNA gene, which has multiple copies and varies among bacterial species. A primer pair specific for rpoB was confirmed to amplify rpoB in a wide range of bacterial species after we assessed 49 strains isolated from five kinds of fruits and vegetables. We purchased fruits and vegetables from retail shops and enumerated the bacteria associated with them by use of real-time PCR and compared this to the number found by the culture method. We found a high correlation between the threshold PCR cycle number when compared with the plate count culture number. The real-time PCR assay developed in this study can enumerate the dominant bacterial species in ready-to-eat fruits and vegetables. 相似文献
996.
Kawabe Y Naka T Ando-Noumi N Matsumoto H Ono K Nishijima K Kamihira M Iijima S 《Journal of Bioscience and Bioengineering》2006,102(6):518-523
We examined the transport of human immunoglobulin G (IgG) subclasses and fusion proteins with the Fc region of human IgG to the egg yolk, after the proteins were injected into a vein of hens. Human IgGs were efficiently transported and accumulated into the yolk, whereas the proteins were not detected in the egg white. Among human IgG subclasses, IgG2 was transported most efficiently. Fc-fusion proteins injected were also transported into the yolk. A fusion protein with the Fc region derived from human IgG2 was more efficiently transported into the yolk than the counterpart fusion with the Fc region from human IgG1. This study shows that the recovery of recombinant antibodies and Fc-fusion proteins from the yolk is an effective method in transgenic chicken bioreactors. 相似文献
997.
998.
Akihiro Nakano Tetsuhiko Maeda Hiroshi Ito Masao Masuda Yoshiaki Kawakami Manabu Tange Toru Takahashi Keiichi Nishida 《International Journal of Hydrogen Energy》2012
We have been performing research on the Totalized Hydrogen Energy Utilization System (THEUS) which has applications to commercial buildings and a planned added function of supplying energy to stations for hydrogen and electric vehicles. In that case we will utilize liquid hydrogen transported from a hydrogen station and all Boil-Off Gas (BOG) will be recovered in THEUS’s metal hydride tanks. It is known that BOG is chiefly composed of para-hydrogen, which has different thermo-physical properties from normal hydrogen. It has been reported that some metal hydride alloys work as a catalyst to accelerate the para-ortho conversion and the conversion proceeds relatively fast in the case of La–Ni5. The conversion is considered to be an endothermic reaction. A misch metal (Mm)-Ni5 metal hydride alloy, which contained La and Ni, was used in our THEUS metal hydride tank. To examine the effect of the para-ortho conversion on the THEUS operation, we investigated the absorption/desorption characteristics of the metal hydride tank with BOG. We confirmed that the effect of the heat of conversion was very small and BOG could be treated as normal hydrogen for practical application. 相似文献
999.
1000.
Saito M Kitamura A Murahashi M Yamanaka K Hoa le Q Yamaguchi Y Tamiya E 《Analytical chemistry》2012,84(13):5494-5500
Herein, a nanoporous alumina was fabricated to use as a mold in transforming nanopillar structures onto a thin film polymer by thermal nanoimprint lithography (NIL). The size of the pores was successfully controlled by varying the applied voltages and etching time. These nanoporous structures were transferred to the Cyclo-olefin polymer (COP) film surface from the porous mold by a thermal nanoimprinting process. A plasmonic substrate was fabricated by sputtering a thin layer of gold onto this nanopillar polymer structure, and the refractive index response in a variety of media was evaluated. Finally, the biosensing capacity of this novel plasmonic substrate was verified by analysis of Human immunoglobulin and achieved a minimum detection limit of 1.0 ng/mL. With the advantages of mass production with consistent reproducibility stemming from the nanoimprint fabrication process, our gold-capped polymeric pillars are ready for the transition from academic interest into commercialization systems for practical use in diagnostic applications. 相似文献