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71.
Methanol, ethanol, straight-chain propanol, isopropanol, straight-chain butanol, sec-butanol, tert-butanol, straight-chain pentanol, and iso-pentanol were used for the reaction of coal with NaOH-alcohol at 290 °C for 1 h. All the products dissolved in pyridine with an extraction yield > 80 wt%. Straight-chain alcohols are less reactive than the secondary alcohols owing to the differences in hydrogen donating ability.  相似文献   
72.
The environmental stability in distilled water and the failure mechanism of cathodically chromated tin, lead, and lead/tin alloy joints bonded with an ethylene–acrylic acid copolymer have been investigated by T-peel tests and ESCA and SEM analyses of the fractured surfaces. The peel strength of chromated lead/tin alloy joints and of both untreated and chromated tin joints is kept unchanged with water immersion, whereas that of untreated lead/tin alloy joints and of both untreated and chromated lead joints decreases rapidly with water immersion. ESCA and SEM observations show that lead/tin alloy surfaces consist of both lead and tin phases and that the tin phase interface deteriorates gradually with water immersion after premature deterioration of the lead phase interface. The stabilization effect of chromate treatments for lead/tin alloy joints is due to retardation of the underfilm corrosion of the tin phase.  相似文献   
73.
Fatty acid synthetase was isolated from guinea pig Harderian gland. This enzyme complex exhibited a unique character as compared with the fatty acid synthetase from the liver of the same animal. The former enzyme produced many odd-numbered and methyl-branched fatty acids in the presence of methylmalonyl-CoA. These fatty acids are characteristic components of the lipid secreted from this gland. The chemical structure of this lipid has been identified as 1-O-alkyl-2,3-diacylglycerol by previous work from this laboratory (Yamazaki, T., Seyama, Y., Otsuka, H., Ogawa, H., & Yamakawa, T. (1981) J. Biochem. 89, 683-691). Apparent Km values (5 X 10(-6) M) for acetyl-CoA and propionyl-CoA were the same, but the Vmax for propionyl-CoA was much higher than that for acetyl-CoA. The pI value of the fatty acid synthetase from Harderian gland was 5.3, and the molecular weight of the enzyme was 9 X 10(5) daltons. The beta-ketoacyl reductase had pro-S stereospecificity and the enoly reductase had pro-R stereospecificity for NADPH. The results presented in this paper indicate that the fatty acid synthetase from guinea pig Harderian gland can produce a set of fatty acids needed for the synthesis of the lipid secreted from this gland, and that the fatty acid synthetase has a characteristic organ specificity.  相似文献   
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75.
To obtain a coding system for multiplex detection, we have developed a method to synthesize a new type of nanomaterial called composite organic-inorganic nanoparticles (COINs). The method allows the incorporation of a broad range of organic compounds into COINs to produce surface enhanced Raman scattering (SERS)-like spectra that are richer in variety than fluorescence-based signatures. Preliminary data suggest that COINs can be used as Raman tags for multiplex and ultrasensitive detection of biomolecules.  相似文献   
76.
The extraction mechanism of copper from an aqueous ammonia-ammonium nitrate mixture by an n-hexane solution of Versatic 10 was studied from the standpoints of the equilibrium distribution of copper between aqueous and organic phases, the aqueous solubility and interfacial adsorption equilibrium of Versatic 10 and the extraction rate of copper.The equilibrium relations of the distribution of copper and the aqueous solubility and the interfacial adsorption of Versatic 10 were interpreted quantitatively and these equilibrium constants were evaluated.The extraction rate of copper was found to be proportional to the copper concentration in the aqueous phase, inversely proportional to the hydrogen ion concentration and independent of the Versatic 10 concentration in the organic phase. From the experimental results of the extraction rate and the interfacial adsorption equilibrium, it was inferred that the extraction rate was controlled by the elementary reaction between the copper ion in the aqueous phase and the anionic species of Versatic 10 adsorbed at the interface.  相似文献   
77.
78.
PURPOSE: Extracellular signal-regulated kinase 2 (ERK2) participates in the phosphorylation cascade that is activated in the an early intracellular response to various hormones and growth factors. We examined the expression and distribution of the ERK2 protein and mRNA in the rat retina before and after light exposure. METHODS: Rats were held on a 12 hr light/dark cycle and their retinas were removed and examined either just before or 2 or 30 min after light exposure. The tissue was processed for Western blotting to evaluate the presence of the protein for ERK2, and for in situ hybridization to evaluate the mRNA of ERK2. RESULTS: The Western blotting method showed a strong specific staining of a 42 kDa protein band in the retinal samples. This band corresponded to the expected size of p42 MAP kinase (ERK2). In situ hybridization histochemistry showed an intense localization of ERK2 mRNA in the outer nuclear layer (ONL), the inner nuclear layer (INL), and the ganglion cell layer (GCL) of the retina. The intensity and distribution of these signals did not differ among the animals, regardless of exposure to light. CONCLUSIONS: While ERK2 may be involved in the signal transduction system activated in retinal cells by light exposure, its precise role remains to be defined.  相似文献   
79.
80.
To clarify the effects of purple corn color, enzymatically modified isoquercitrin (EMIQ), and isoquercitrin (IQ), registered as natural food additives in Japan, on liver carcinogenesis in vivo, a medium-term bioassay was employed. A total of 100 male F344 rats were divided into 5 groups; groups 1 to 4 were given a single intraperitoneal injection of diethylnitrosamine (200 mg/kg b.w.) on day 1. From weeks 2 to 8, they were administered basal diet purple corn color, EMIQ, or IQ as containing test chemicals at doses of 1.0% (groups 1 and 5), 0.1% (group 2), 0.01% (group 3), or 0% (group 4) (experiments 1, 4, and 5). All rats were subjected to two-thirds partial hepatectomy at week 3 and were sacrificed at week 8. Purple corn color exerted no significant modifying effects on GST-P positive foci, preneoplastic foci, development in the liver. However, serum of rats treated with purple corn color provided evidence of antioxidant power significantly by potential antioxidant (PAO) test in vivo (experiment 2). And microarray analyses showed purple corn color to induce RNA expression such as P450 (cytochrome) oxidoreductase, phosphatidylinositol 3-kinase, and phospholipase A2 (experiment 3). Higher doses of EMIQ or IQ with strong antioxidant power in vivo by PAO test treated groups were correlated with smaller numbers of GST-P positive foci, with Spearman's rank correlation coefficients of P= 0.002 and P= 0.049, respectively (experiments 4 and 5). Therefore, the tested food additives may be effective as antioxidants in vivo and have chemopreventive potential against liver preneoplastic lesion development.  相似文献   
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