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111.
An electron microscopic DOPA reaction test of fetal skin was used for the prenatal diagnosis of tyrosinase-negative oculocutaneous albinism (OCA). The subject was a 34-year-old Japanese woman in her second pregnancy. Her first child, born in 1982, had been previously examined and confirmed to have tyrosinase-negative OCA. The parents requested a prenatal diagnosis and we sampled skin from the upper trunk of the fetus. On conventional electron microscopy, the development of melanosomes in interfollicular melanocytes had progressed no further than stage II. Fetal skin samples incubated with L-DOPA solution indicated a lack of tyrosinase activity and showed that the melanosomes had not progressed beyond stage II. In skin samples from the trunks of three Japanese fetuses aborted for other reasons at 19–20 weeks of gestation, most premature melanosomes were further melanized to stage IV after incubation with L-DOPA solution. A prenatal diagnosis of tyrosinase-negative OCA was made. The parents requested a termination and skin biopsies of the abortus confirmed the diagnosis. This study shows that tyrosinase is normally present in melanocytes of the fetal epidermis at 20 weeks' gestation, and that the electron microscopic DOPA reaction test of a fetal skin biopsy specimen is safe and practical, and provides reliable information for making a prenatal diagnosis of tyrosinase-negative OCA in the second trimester.  相似文献   
112.
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous in the atmosphere and they mostly stem from the imperfect combustion of fossil fuels and biofuels. PAHs are inherently associated with homogenous fine particles or distributed to different-sized particles during the aging of air masses. PAHs carried by fine particles undergo a long-range transport to remote areas while those adsorbed on coarse particles have a shorter lifetime in ambient air. More importantly, PAHs with higher molecular weights tend to be bound with finer particles and can deeply enter the lungs, posing severe health risks to humans. Thus, the environmental fate and health effects of particulate PAHs are strongly size-dependent. This review summarizes the size distributions of particulate PAHs freshly emitted from combustion sources as well as the distribution patterns of PAHs in ambient particles. It was found that PAHs from stationary sources are primarily bound to fine particles, which are slightly larger than particles to which PAHs from mobile sources are bound. In ambient air, particulate PAHs are distributed in larger size modes than those in the combustion fume, and the particle size decreases with PAH molecular weight increasing. The relevant mechanisms and influencing factors of particle size distribution changes are illustrated in this article, which are essentially attributed to combustion and ambient temperature as well as the physical and chemical properties of PAHs. Overall, the study on the particle size distribution of PAHs will contribute for a full understanding of the origin, atmospheric behaviors and health effects of particulate PAHs.  相似文献   
113.
To evaluate the influence of anthropogenic emission of HCl on the air quality in the Kanto district of Japan, the atmospheric budgetof non-seasalt Cl (nssCl) was analyzed. The Kanto district, which consists of the Tokyo metropolis and the six surrounding prefectures, is the most densely populated region in Japan. The emission intensity of HCl is extremely high compared with those in other regions and most western countries. In this study, the annual wet and dry depositions of nssClwere estimated on a 0.25 × 0.25° grid over the Kanto district based on the concentration monitoring resultsand meteorological data. The budget analysis was conducted by comparing the estimated deposition with the emission of HCl. As a result, the annual total (wet + dry) deposition of nssCl was estimated to be 32 kt yr-1, which closely agreed with HCl emission (36 kt yr-1) from waste incineration in this area. The result suggested that the anthropogenic emission of HCl had a significant influence on the air quality and the deposition of acidity in this area.  相似文献   
114.
Parasporin, a Bacillus thuringiensis parasporal protein, is unique in having a strong cytocidal activity preferential for human cancer cells. In this study, we characterized parasporin activities associated with three novel geographical isolates of B. thuringiensis. Parasporal inclusion proteins of the three isolates were highly toxic to human uterus cervix cancer cells (HeLa), but not to non-cancer uterine smooth muscle cells (UtSMC). Inclusions of the isolates lacked insect toxicity and hemolytic activity against sheep erythrocytes. Ouchterlony immunodiffusion tests revealed that the proteins of the three isolates are immunologically closely related to parasporin-1 (Cry31A), but dissimilar to the three other existing parasporin groups. Our results provide evidence that the parasporin-1-producing organism is a common member in B. thuringiensis populations occurring in natural environments of Japan.  相似文献   
115.
In order to develop effective conservation strategies for endangered migratory species, the link between feeding and breeding grounds needs to be clarified. In this study, the genetic compositions of consecutive Japanese feeding aggregations of green turtles (Chelonia mydas) along the Kuroshio Current were examined by mixed-stock analyses of mitochondrial DNA control-region sequences. The results indicated that the southern feeding aggregation around Yaeyama (24.3°N, 124.0°E) was sourced from various Pacific rookeries in the Yaeyama, Ogasawara, Western Pacific, and Indian Oceans and Southeast Asia. Among northern feeding aggregations, the Ginoza (26.5°N, 128.0°E) aggregation was also sourced from the Western Pacific Ocean, but the Nomaike (31.4°N, 130.1°E), Muroto (33.2°N, 134.2°E), and Kanto (35.6°N, 140.5°E) aggregations were contributed mostly by the closer Ogasawara rookeries. The reduced contribution from tropical Pacific rookeries to northern feeding aggregations and the significant correlation between genetic differentiation and geographical distance matrices of feeding aggregations indicated that most hatchlings from these regions transported by the Kuroshio Current settle in upstream feeding grounds along the Japanese archipelago, implying that current flow influences the composition of feeding aggregations. Differences in the composition of relatively close neritic feeding aggregations have important conservation implications, for which both regional and multinational conservation strategies are needed.  相似文献   
116.
An intensive field survey, with 6-h measurement intervals, of concentrations of chemical species in particulate matter and gaseous compounds was carried out at coastal sites on the Sea of Japan during winter. The concentration variation of SO2(g) and HNO3(g) were well correlated, whereas the NH3(g) concentration variation had no correlation with those of SO2(g) and HNO3(g). The NH4 + (p)/non-sea-salt- (nss-)SO4 2 −(p) ratio in particulate matter was mainly affected by the location of the sampling site. One or more concentration peaks of nss-Ca2 + for survey period were observed. Backward trajectories analyses for the highest nss-Ca2 + concentration peaks showed some inconsistency in pathways. We consider that insufficient mixing of the atmosphere and/or insufficient time for the transported air pollutants to react with those discharged locally are the most likely explanations for the discrepancies between the measured products [HNO3][NH3] and the calculated values.  相似文献   
117.
To estimate the contribution of transboundary transported air pollutants from other Asian countries to Japan in ionic concentrations in fog water in March 2005, the Community Multiscale Air Quality (CMAQ) modeling system was utilized with meteorological fields produced by the 5th generation Mesoscale Model (MM5). For meteorological predictions, the model well reproduced the surface meteorological variables, particularly temperature and humidity, and generally captured fog occurrence. For chemical predictions, most of the model-predicted monthly mean concentrations were approximately within a factor of 2 of the observations, indicating that the model well simulated the long-range atmospheric transport from the Asian Continent to Japan. For SO42?, NO3? and NH4+, the contribution rates of the transboundary air pollution in the Kinki Region of Japan ranged from 69 to 82% for aerosols, from 47 to 87% for ionic concentrations in rain, and from 55 to 79% for ionic concentrations in fog. The study found that the transboundary air pollution also affected ionic concentrations in fog as well as aerosol concentrations and ionic concentrations in rain.  相似文献   
118.
Chemical recycling of waste poly(carbonate) (PC) to coproduce bisphenol A (BPA) and carbohydrate carbonates was studied by selecting glycerol (Gly) and glucose (Glu) as model carbohydrates (CHs). In advance of the reaction of PC with CHs, reactions with diphenyl carbonate were examined as a model PC. In dioxane at 100°C using NaOH as catalyst, Gly was converted to cyclic carbonate hydroxymethyldioxolane (HMDO) at 98% and Glu was converted to the dicarbonate (Glu-DC) at 46%, in pyridine, in addition to the production of phenol. Similar treatment of PC with Gly using KOH as a catalyst produced HMDO and BPA at very high yields and treatment with Glu produced Glu-DC and BPA in 38%–42% yields. Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6  相似文献   
119.
The chemistry and flow of water in the abandoned Tomitaka mine of Miyazaki, western Japan were investigated. This mine is located in a non-ferrous metal deposit and acid mine drainage issues from it. The study was undertaken to estimate the quantities of mine drainage that needs to be treated in order to avoid acidification of local rivers, taking into account seasonal variations in rainfall. Numerical models aimed to reproduce observed water levels and fluxes and chemical variations of groundwater and mine drainage. Rock–water interactions that may explain the observed variations in water chemistry are proposed. The results show that: (1) rain water infiltrates into the deeper bedrock through a highly permeable zone formed largely by stopes that are partially filled with spoil from excavations (ore minerals and host rocks); (2) the water becomes acidic (pH from 3 to 4) as dissolved oxygen oxidizes pyrite; (3) along the flow path through the rocks, the redox potential of the water becomes reducing, such that pyrite becomes stable and pH of the mine drainage becomes neutral; and (4) upon leaving the mine, the drainage becomes acidic again due to oxidation of pyrite in the rocks. The present numerical model with considering of the geochemical characteristics can simulate the main variations in groundwater flow and water levels in and around the Tomitaka mine, and apply to the future treatment of the mine drainage.  相似文献   
120.
The degree of cadmium (Cd) contamination in wildlife is often used as an indicator in the environmental monitoring of Cd poisoning. However, previous studies have not clarified the correlation between levels in wildlife and levels in the environment by comparing levels among different species of animals; therefore, assessing the level of pollution in this manner is not considered a reliably accurate indicator of levels in the environment. The aim of this study was to establish a new indicator for the non-polluted warm-blooded animals, one that is not species-dependent, which will facilitate using different species for Cd monitoring. First, the previous publications regarding Cd contents in wildlife, 27 reports in which Cd contents were represented as arithmetic means and described for both kidney and liver were selected. A regression line (CSRL) between Cd contents of kidney and that of liver was obtained in a high correlation coefficient (R 2 = 0.943, P < 0.01). The mean values from land and waterfowl, terrestrial mammals, seabirds, marine mammals, and non-polluted humans were located on the line and aligned in order. CSRL might allow an accurate determination of whether an animal is polluted by Cd. CSRL was confirmed using well-established and widely recognized pollution models such as Itai-itai patients and Cd-exposed experimental animals. The Cd contents from these models were located in different positions relative to CSRL depending on the level of contamination. Thus, this new indicator determining the Cd-pollution status of animals would be useful for environmental monitoring.  相似文献   
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