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71.
Volatile organic compounds (VOCs) from wood and their effects on artifacts are of intense interest to museum staff who must strictly manage the preservation environment. In this study, the causal substances of deterioration were inferred by comparison with laser Raman (LR) spectra of deterioration products. The artifact samples were deteriorated using VOCs from woods (WV test), and using specific substances that occur in wood VOCs (SV test). The deteriorated samples were analyzed by LR spectroscopy and the results of the WV and SV tests were compared. Hinokitiol and acetic acid were found to be two of the main causal substances of deterioration in western red cedar. Deterioration of iron and copper by spruce did not appear to be caused by acetic acid, as is generally assumed, but by some other unknown compound(s). Sensitivity to wood-based VOC components depended on the type of artifact. In western red cedar, mitsudasou (litharge) was very sensitive to acetic acid, while other artifacts were sensitive to hinokitiol. The LR method used in this study is very useful for the inference of causal substances of deterioration based on the detection of small amounts of deteriorated products such as those generated by deterioration due to wood VOCs. Part of this article was presented at the 25th Annual Meeting of the Japan Society for the Conservation of Cultural Property, Kyoto, June 2003  相似文献   
72.
Although tropomyosin is known to be a major allergen of crustaceans, its structural information is limited to only five species. In this study, tropomyosin was confirmed to be a major allergen in six species of crustaceans (black tiger prawn, kuruma prawn, pink shrimp, king crab, snow crab, and horsehair crab) by immunoblotting. Then, the amino acid sequences of tropomyosins from these crustaceans were elucidated by a cDNA cloning technique. Sequence data for crustacean tropomyosins including the obtained results reveal that fast tropomyosins are contained in shrimps (or prawns) and lobsters, slow tropomyosins in crabs, and both tropomyosins in crayfishes and hermit crabs. Although fast and slow tropomyosins share a high sequence identity (about 90%) with each other, significant differences are observed in specific regions between both tropomyosins.  相似文献   
73.
A method for the comprehensive analysis of hydrophilic metabolites, based on a combination of high-performance liquid chromatography and mass spectrometry, is described. We evaluated three types of stationary phases to achieve the separation of highly hydrophilic metabolites. Good chromatographic retention and separation of these metabolites were achieved on a pentafluorophenylpropyl-bonded silica column with gradient elution, using 0.1% aqueous formic acid and acetonitrile as the mobile phase. The optimized conditions allowed the comprehensive determination of the standard 49 kinds of amino acids, 6 kinds of amines, 45 kinds of organic acids, 18 kinds of nucleic bases, 5 kinds of nucleosides, and 14 kinds of nucleotides, and then the linearity, dynamic range, detection limit, and precision of the retention time and the peak area were validated. We applied this method for the targeted analysis of the components in soy sauce. The results from the quantitative determination of amino acids were compared to those obtained with an amino acid analyzer, and the accuracy was in the range between 85 and 119%. The accuracy of other detected components was confirmed to be 105-133% by the recovery rate after the addition of standard compounds. We also applied the method for the nontargeted metabolic profiling of the components in several kinds of soy sauces with the principal component analysis. They were classified by the manufacturing methods, and the components that corresponded to the differences were identified. This method could be useful for the targeted analysis of hydrophilic metabolites as well as their nontargeted metabolic profiling.  相似文献   
74.
Antioxidant activity of carotenoids is suggested to be one of the factors for their disease preventing effects. Marine carotenoids fucoxanthin and its two metabolites, fucoxanthinol and halocynthiaxanthin, have been shown to exhibit several biological effects. The antioxidant activities of these three carotenoids were assessed in vitro with respect to radical scavenging and singlet oxygen quenching abilities. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of fucoxanthin and fucoxanthinol was higher than that of halocynthiaxanthin, with the effective concentration for 50% scavenging (EC 50) being 164.60, 153.78, and 826.39 microM, respectively. 2,2'-Azinobis-3-ethylbenzo thizoline-6-sulphonate radical scavenging activity of fucoxanthinol (EC 50, 2.49 microM) was stronger than that of fucoxanthin (EC 50, 8.94 microM). Hydroxyl radical scavenging activity as measured by the chemiluminescence technique showed that the scavenging activity of fucoxanthin was 7.9 times higher than that by fucoxanthinol, 16.3 times higher than that by halocynthiaxanthin, and 13.5 times higher than that by alpha-tocopherol. A similar trend was observed when the hydroxyl radical scavenging was assessed by the electron spin resonance (ESR) technique. ESR analysis of the superoxide radical scavenging activity also showed the superiority of fucoxanthin over the other two carotenoids tested. Singlet oxygen quenching ability of the three carotenoids was lower than that of beta-carotene, with quenching rate constants ( k Q, x10 (10) M (-1) s (-1)) being 1.19, 1.81, 0.80, and 12.78 for fucoxanthin, fucoxanthinol, halocynthiaxanthin, and beta-carotene, respectively. The higher radical scavenging activity of fucoxanthin and fucoxanthinol compared with halocynthiaxanthin is assumed to be due to presence of the allenic bond.  相似文献   
75.
Helminth parasites were collected from 14 raccoon dogs (Nyctereutes procyonoides viverrinus) and 2 Japanese weasels (Mustela itatsi sho) on Yakushima Island, Kagoshima Prefecture (Kyushu), Japan. In addition to trematodes and nematodes reported separately, everted cystacanths of 3 bird acanthocephalans (Mediorhynchus robustus in 5 animals, Porrorchis leibyi in 2 animals, and Sphaerirostris lanceoides in 1 animal) were collected from the raccoon dogs introduced recently on this World Natural Heritage Area. A cystacanth of P. leibyi was collected also from a weasel indigenous to this island that were killed by traffic accidents. Recovery of everted cystacanths of M. robustus from the intestine of raccoon dogs was remarkably frequent (36%), suggesting that this acanthocephalan should be highly prevalent in passerine hosts on Yakushima Island, and the animals might vigorously take insect hosts or paratenic hosts. Furthermore, the present report is the second on M. robustus after its first record in Japan (Aichi Prefecture, Honshu) as M. garruli from a Eurasian jay (Garrulus glandarius japonicus) by Yamaguti in 1939. Porrorchis leibyi has never been recorded in Japan.  相似文献   
76.
The purpose of present study was to determine annual changes in serum progesterone (P(4)) concentrations and to clarify basic reproductive characteristics, such as breeding season, estrous cycle, and puberty in female bharals (Pseudois nayaur). Blood was collected from 9 female bharals once or twice weekly for approximately one year. Serum P(4) concentrations were determined by radioimmunoassay. Serum P(4) concentrations showed remarkable and cyclic changes between November/December (winter) and May/June (late spring). The mean estrous cycle was 24.9 +/- 0.5 days. Chasing insistently to other females and discharge of mucus from the vulva were observed around the time when the serum P(4) concentrations began to increase. The chasing behavior and discharge of mucus were considered to be external indicators of estrus in female bharals. Serum P(4) concentrations of a pregnant female had non-cyclic changes, and the values remained high. In this study, all 37 deliveries were between April and September, and about 70% of these were concentrated in May and June. The conception month determined on the day of birth was between October and April for all animals, and the most common month was in December (54%). This month corresponded to an early stage of the period when the serum P(4) concentrations changed cyclically. These results indicate that many female bharals become pregnant at the beginning of the breeding seasons and, if they do not become pregnant, the estrous cycle, about 25 days in length, is repeated.  相似文献   
77.
A female congenic rat produced by repeated backcrossing of Nihon rats, a model for hereditary renal cell carcinoma, to Brown Norway rats was necropsied at 24 months of age. At necropsy, a white mass about 1 centimeter in size was observed in the thoracic cavity, and the mass partly adhered to the esophagus and the diaphragm. Histologically, the mass was clearly circumscribed by connective tissue, and consisted of neoplastic cuboidal epithelial cells that showed cystic tubular proliferation. Some islands of well-differentiated hepatocytes and some vessels were observed in the mass. Immunohistochemically, the tumor cells were strongly positive for cytokeratin and partly positive for vimentin but were negative for mesothelin and Von Willebrand Factor. The positive rate for Ki-67 was 2.4%. Based on these histological and immunohistochemical evidences, we diagnosed this tumor as a cystic cholangioma that might have arisen from the ectopic hepatic tissue in the thoracic cavity.  相似文献   
78.
Although our previous report demonstrated that adiponectin and AdipoR1 gene expressions changed among different lactation stages in the bovine mammary gland, its in vivo kinetics remain unclear in ruminant animals. In this study, we investigated the changes in circulating concentrations of adiponectin, as well as other metabolic hormones and metabolites, (i) during the periparturient period and (ii) among different lactation stages, in Holstein dairy cows. In experiment 1, serum adiponectin concentrations increased after parturition. Serum insulin concentrations were lower in the postpartum than prepartum period, whereas serum growth hormone (GH) concentrations increased in the postpartum period. Serum nonesterified fatty acids (NEFA) levels were increased during the postpartum period and were dependent on the parity. In experiment 2, there was no significant difference in plasma adiponectin concentrations among lactational stages. Plasma insulin concentrations tended to be lower in early lactation while plasma GH levels tended to be higher. Plasma NEFA concentrations were significantly lower in mid‐ and late‐lactation stages than non‐lactation stages. These findings indicate that elevation of serum adiponectin might be involved in energy metabolism just around parturition, and might exert its action through regulation of receptor expression levels in target tissues in each lactational stage in Holstein dairy cows.  相似文献   
79.
Rice (Oryza sativa L.) is the main food for people in Laos, where it has been grown and eaten since prehistory. Diverse landraces are grown in Laos. ‘Khao Kai Noi’, a landrace favored for its eating quality, is held in the nationwide collection of traditional landraces in the Lao national genebank. Genetic diversity is crucial for sustainable use of genetic resources and conservation. To investigate the genetic diversity of ‘Khao Kai Noi’ for conservation, we genotyped 70 accessions by using 23 polymorphic simple sequence repeat markers. The markers generated 2 to 17 alleles (132 in total), with an average of 5.7 per locus. The total expected heterozygosity over all ‘Khao Kai Noi’ accessions was 0.271. Genetic variation was largest among accessions and smallest within accessions. Khao Kai Noi accessions were classified into three different genetic backgrounds, but there was unclear association between the three inferred population and name subgroups and geographical distribution. Most of the accessions were clustered with temperate japonica and showed genetic relatedness to rice from neighboring provinces of Vietnam, suggesting a Vietnamese origin. The results of this study will contribute to the conservation, core collection and future breeding of the Khao Kai Noi population.  相似文献   
80.
As part of our exploratory drug research on the larva migrans that causes roundworm in dogs and cats, this study was carried out to clarify the effect of free and liposome-entrapped (LE) albendazole in Toxocara canis infected mice. In infected mice, evaluation of mobility and number of larva were examined in detail in the brain, skeletal muscle and liver. Larva mobility was evaluated by using the relative mobility (RM) value. Albendazole was LE as one of the drug delivery systems (DDSs). Polyethylene glycol (PEG) was added to the liposome in order to avoid evoking a response by the reticuloendothelial system (RES). By using the albendazole PEG-LE delivery system, it was possible to target the larvae in the mouse brain and liver resulting in a decrease in the number of larvae. In the skeletal muscle of the infected mice, the intraperitoneal dosages of PEG-LE albendazole did not cause a complete decrease in the number of larvae, even though free albendazole did cause the number to decrease. Therefore, it is necessary to take into consideration the migrating stage of the larvae before the initiation of any drug administration.  相似文献   
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