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Jun Murotsuki MD Shigeki Uehara Kunihiro Okamura Akira Yajima Kazuhiro Murakami 《黑龙江环境通报》1994,14(7):637-639
A case of type III congenital cystic adenomatoid malformation of the lung was successfully diagnosed prenatally by fetal lung biopsy. We performed this procedure at 22 weeks of gestation, using a biopsy gun system under ultrasound guidance. The pregnancy was undisturbed by the procedure but as the condition was incompatible with life, an abortion was performed. The diagnosis was confirmed at post-mortem examination. Fetal lung biopsy appears to be a useful method for prenatal diagnosis of fetal lung disorders. 相似文献
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为实现对苯酚废水治理工艺的优化,针对传统包埋法制备固定化细胞的工艺方法进行改进,选用磁性纳米颗粒制备磁固定化细胞,将其与电芬顿法结合构建耦合体系,利用耦合协同作用实现催化剂的重复利用,并依托微生物的良好降解性能与稳定性提高苯酚降解率,进一步实现对苯酚废水治理工艺的系统优化。 相似文献
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Removal of organic polyelectrolytes and their metal complexes by adsorption onto xonotlite 总被引:1,自引:0,他引:1
Katsumata H Kaneco S Matsuno R Itoh K Masuyama K Suzuki T Funasaka K Ohta K 《Chemosphere》2003,52(5):909-915
Natural organic polyelectrolytes (humic and fulvic acids) and their metal complexes were removed by adsorption onto xonotlite. The removal percentages of humic and fulvic acids by xonotlite were approximately 80% and 30%, respectively. Humic acid removal from solution by adsorption onto xonotlite took place more readily than fulvic acid removal. The molecular weight distributions of the humic substances remaining in solution after adsorption with the xonotlite were measured with size exclusion chromatography. A comparison of molecular weight distributions demonstrated conclusively that large molecular weight components were adsorbed preferentially, indicating that adsorption efficiency depends on the number of functional groups of humic substances. Furthermore, the surface topography of the adsorbent was observed before and after adsorption by scanning electron microscopy. The calculated heat of adsorption was of 330 kJ mol(-1) which was evaluated from the Clapeyron-Clausius equation. Therefore, the adsorption type can be considered chemical. Since xonotlite can be easily synthesized and obtained at low cost, the adsorption method of humic and fulvic acids is superior to their precipitation. 相似文献
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Yoshitaka Yonezawa Manabu Fukui Shigeki Masunaga Yoshikuni Urushigawa 《Chemosphere》1994,28(12):2179-2184
The relation between dechlorination activities of 1,2,4-trichlorobenzene and anaerobic microbial activity were studied in the sediment collected at three sites in Ise Bay in Japan. The degradation rate of spiked 1,2,4-trichlorobenzene (3nmol ml−1) ranged from 15 to 35 pmol day−1 ml−1 wet sediment and about 1/3 to 1/2 of degraded the trichlorobenzene was recovered as dechlorinated products. Among the dichlorobenzenes, the 1,2-isomer had the highest and 1,3-isomer had the lowest production rate. Comparing the three sampling sites, the trichlorobenzene degradation and dichlorobenzenes production rates were related to the sulfate reducing activity for the unit number of sulfate reducing bacteria. Production rates of dichlorobenzenes were completely inhibited by adding molybdate (20 mM), nitrate (60 mM), and formaldehyde solution (4 %). These results indicated that dechlorination activity in the Ise Bay sediment was supported by sulfate reduction activity in the sediment, and not supported by any other anaerobic microbial activity. 相似文献
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Jiro Moriguchi Takafumi Ezaki Teruomi Tsukahara Katsuya Furuki Yoshinari Fukui Satoru Okamoto 《毒物与环境化学》2013,95(1):119-133
The present study was initiated to examine urinary α1-microglobulin (α1-MG-U) levels among non-smoking women in the general population in Japan. A previously established database on spot urine samples from adult woman volunteers in 10 non-polluted areas all over Japan was re-examined. The data examined were on α1-MG-U, cadmium, calcium, magnesium and zinc levels in urine (Cd-U, Ca-U, Mg-U and Zn-U, respectively), urinary creatinine (CR or cr), urine specific gravity (SG or sg), smoking habits and age. Thus, 8975 never-smoking women were selected for statistical analyses. The grand geometric mean (GM) for α1-MG-U among the population was 2.1?mg/L or 2.5?mg/g?cr, depending on the correction for urine density. It was 1.1?µg/L or 1.3?µg/g?cr for GM Cd-U. The inter-area difference in α1-MG-U was <1.5?mg/g?cr or <0.7?mg/L; the area with the highest or lowest GM Cd-U was not always highest or lowest in GM α1-MG-U. The correlation coefficient (0.53) between log?Cd-U and log?α1-MG-U (both without urine density correction) became substantially smaller when the analyte levels were corrected for CR (0.25) or SG (0.26). In multiple regression analysis, the power of influence of the five independent variables (log?Cd-U, Ca-U, Mg-U, Zn-U and age) in combination was small (R 2?≦?0.13). In contrast, logistic regression analysis suggested that α1-MG-U might be elevated as a function of an increase in Cd-U, depending on the cut-off values. Discussion was made on dose (Cd-Ucr) and response (α1-MG-Ucr) relationship based on information available in literatures to show that the increment in α1-MG-Ucr per Cd-Ucr was much greater when Cd-Ucr was large, e.g., in excess of 10?µg/g?cr. 相似文献
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Yoko Fujikawa Masami Fukui Doug J. Drew Tjalle T. Vandergraaf 《Journal of contaminant hydrology》1993,14(3-4)
Breakthrough curves of 137Cs and tritiated water injected instantaneously into artificial fractures in Lac du Bonnet granite were analyzed using the analytical solution for a single rock-fracture system and assuming the linear sorption isotherm of the solute. Parameters of nuclide diffusion and sorption in rock matrices, obtained by fitting, varied depending on the flow velocity in the fractures. According to theoretical calculations, different fracture flow velocities lead to different diffusion distances of nuclides in matrices at the same injection volume. As microscopic inhomogeneity is considered to exist in the rock matrix, the average diffusion-sorption characteristics of the matrix within the diffusion distance may have varied with the fracture flow velocity. Surface sorption was marked in fractures that had relatively high matrix sorption-diffusion capacities. The phenomenon was interpreted using the theoretical relationships developed between the surface sorption, matrix sorption and pore diffusion coefficient, and the porosity of matrices.The effect of the nonlinear sorption of solute was examined by numerically solving model equations that incorporate the nonlinear isotherm. This incorporation may contribute to the reduction of deviations between theoretical and experimental BTC's. 相似文献
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Shin Fukui 《Die Naturwissenschaften》2014,101(5):437-446
Symbiosis is one of the most fundamental relationships between or among organisms and includes parasitism (which has negative effects on the fitness of the interacting partner), commensalism (no effect), and mutualism (positive effects). The effects of these interactions are usually assumed to influence a single component of a species’ fitness, either survival or fecundity, even though in reality the interaction can simultaneously affect both of these components. I used a dual lattice model to investigate the process of evolution of mutualistic symbiosis in the presence of interactive effects on both survival and fecundity. I demonstrate that a positive effect on survival and a negative effect on fecundity are key to the establishment of mutualism. Furthermore, both the parasitic and the mutualistic behaviour must carry large costs for mutualism to evolve. This helps develop a new understanding of symbiosis as a function of resource allocation, in which resources are shifted from fecundity to survival. The simultaneous establishment of mutualism from parasitism never occurs in two species, but can do so in one of the species as long as the partner still behaves parasitically. This suggests that one of the altruistic behaviours in a mutualistic unit consisting of two species must originate as a parasitic behaviour. 相似文献
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