Cu、Cd、Pb、Zn、As复合污染对灯心草的生理毒性效应   总被引：3，自引：0，他引：3  

孙健  铁柏清  钱湛  杨佘维  毛晓茜  赵婷  罗荣  青山勋 《土壤》2007,39(2):279-285

通过盆栽试验,以现行土壤环境质量标准为浓度设置依据并结合实际污染土壤研究了不同处理水平的Cu、Cd、Pb、Zn、As5种重金属复合污染对灯心草生长、叶绿素含量及保护酶系统的影响。实验结果表明:5种重金属复合污染对灯心草地上部生长有一定程度的抑制作用,在土壤环境质量二级标准上限值处灯心草地上部生物量减产9.15%,<10%,但地下部生物量减产趋势不明显。复合重金属污染抑制灯心草的光合作用使叶绿素含量减少、叶绿素a/b值降低。在接近土壤环境质量标准低浓度设计范围内,灯心草3种保护酶有逐渐被激活的趋势,表现出一定的协调性共同抵制重金属的毒害。但在高浓度处理水平下,酶活性遭到抑制。生长在矿毒水和铅锌尾矿污染土壤中的灯心草地上部生物量分别下降28.23%和37.1%,但POD、SOD和CAT3种酶活性均高于对照。通过应用综合生态环境效益法,以灯心草为指示植物可以将土壤环境质量二级标准上限值设定为土壤中5种重金属的临界毒性效应值。  相似文献   

Quantitative analysis of the optic nerve of the horse (Thoroughbred)     

Guo X  Aoyama M  Sugita S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(9):971-975

Three optic nerves (L1, R2, R3) 12-18 mm behind the eyeball of the horse (Thoroughbred) were investigated quantitatively under light and electron microscopes. Thin sections at the thickness of 0.35 microm were cut, stained by toluidine blue and observed under the light microscope. The areas of the optic nerve and the axon bundles were 20.03 +/- 1.04 and 16.59 +/- 0.79 mm2 (mean +/- SD, n=3), respectively. The axon numbers for optic nerve L1, R2 and R3, estimated from light micrographs, were about 481 x 10(3), 543 x 10(3), and 494 x 10(3), respectively. Axons of optic nerve L1 were also counted from electron micrographs and the total number of 488 x 10(3) was received. Furthemore, axon diameters of optic nerve L1 were also measured from electron micrographs. The diameter of a circle with the same peripheral length as an axon, was regarded as its diameter. The medullary sheath of the axon was not included during measuring. Altogether 5,744 axons were measured and axon diameters were in a range of 0.23-12.69 microm, with a mean of 2.56 +/- 1.45 microm (mean +/- SD). A regional difference of axonal diameters was found across the optic nerve: the mean diameter of axons in the centrodorsal region (2.28 microm) was the smallest, and had significant difference with those in several peripheral regions (P<0.05).  相似文献   

Antifeedant activity of flavonoids and related compounds against the subterranean termiteCoptotermes formosanus Shiraki     

Wakako Ohmura  Shuichi Doi  Masakazu Aoyama  Sciji Ohara 《Journal of Wood Science》2000,46(2):149-153

Antifeedant activity of some flavonoids and their related compounds against the subterranean termiteCoptotermes formosanus Shiraki was examined with nochoice tests and two-choice tests. The activities of these compounds were evaluated in relation to their chemical structures. All flavonoids tested showed antifeedant activity, whereas catechinic acid, possessing no A-ring or pyran ring in the molecule, showed feeding-preference activity. For the structure-activity relations, it was found that compounds containing two hydroxyl groups at C-5 and C-7 in A-rings showed high antifeedant activity. Furthermore, the presence of a carbonyl group at C-4 in the pyran rings of the compounds was necessary for the occurrence of high activity. 3-Hydroxyflavones and 3-hydroxyflavanones with 3,4-dihydroxylated B-rings exhibited higher activity than those with 4-hydroxylated B-rings.Part of this paper was presented at the 49th annual meeting of the Japan Wood Research Society, Tokyo, April 1999  相似文献   

Sorption of Cr(VI) on the wood of Japanese larch treated with concentrated sulfuric acid     

Masakazu Aoyama  Shingo Saito  Masaaki Tagami 《Journal of Wood Science》2007,53(6):545-549

A carbonaceous sorbent was prepared from the wood of Japanese larch (Larix leptolepis) by dehydration with concentrated sulfuric acid in a 69% yield. The abilities of the sorbent to remove Cr(VI) from aqueous solutions were investigated. Research parameters included the initial solution pH, temperature, and initial concentration of Cr(VI) in solution. The removal of Cr(VI) was highly solution pH dependent and was mainly governed by physicochemical sorption under weak acidic conditions. The equilibrium data fit well in the Langmuir isotherm model. The Langmuir constants were calculated at different temperatures, and the sorption capacity increased with rising temperature, indicating the endothermic nature of the Cr(VI) sorption onto the sorbent. The desorption experiments suggest that the Cr(VI) sorption is generally irreversible, owing to strong interaction of HCrO ₄ ⁻ with the active sites of the sorbent.  相似文献   

Removal of trichloroethylene from aqueous solution by pyrolyzed Japanese cedar bark     

Yasuji Kurimoto  Shuichi Doi  Masakazu Aoyama 《Journal of Wood Science》2001,47(1):76-79

The bark of Japanese cedar (Cryptomeria japonica D. Don) was heated in an N₂ atmosphere at 300–900C for 3h to investigate the surface properties of the pyrolyzed residuces and their ability to remove trichloroethylene (TCE) from aqueous solutions. The specific surface areas (S _N) and total pore volumes (V _N) of the pyrolyzed barks steadily increased with rising pyrolysis temperature; no significant differences in the average pore diameters (D _N) were observed at higher temperatures (600–900C). The adsorption capacities of the pyrolyzed residues for TCE were determined under batch mode conditions using an aqueous solution containing 500g TCE dm^–3. The adsorption data were well fitted to the Freundlich equation. The adsorption capacity of the bark pyrolyzed at 900C was about five times larger than that of commercial activated carbon.This study was presented at the 10th International Symposium on Wood and Pulping Chemistry, Yokohama, June 1999  相似文献   

Changes of decay and termite durabilities of Japanese larch (Larix leptolepis) wood due to high-temperature kiln drying processes     

Shuichi Doi  Masakazu Aoyama  Shigeru Yamauchi  Yasuji Kurimoto 《Journal of Wood Science》2005,51(5):526-530

We investigated the effects of high-temperature drying schedules (120°–130°C) on decay and termite feeding of Japanese larch timbers. Thermogravimetric analysis was conducted to investigate changes of the wood components. Decay and termite feeding tests showed that specimens dried under high-temperature schedules were susceptible against a decaying fungus Fomitopsis palustris and attacks from termites Coptotermes formosanus and Reticulitermes speratus. These drying schedules changed chemical components, which were suggested by the thermal analytical result compared to the control sample. The results of this study indicated that the acceleration of termite feeding takes place even under temperatures that are comparatively lower than that used in our previous research in which 170°C steaming treatment was applied to Japanese larch wood. Decay durability against a brown rot fungus also decreased, possibly from production of low molecular weight fragments when hemicellulose decreased during the high-temperature drying processes.  相似文献   

Structure of xylan from culms of bamboo grass (Sasa senanensis Rehd.)     

Shigeki Yoshida  Atsushi Kuno  Naoto Saito  Masakazu Aoyama  Isao Kusakabe 《Journal of Wood Science》1998,44(6):457-462

Xylan prepared from culms of kumaizasa (Sasa senanensis Rehd.), a representative species of bamboo grass, was hydrolyzed with-xylanase ofStreptomyces olivaceoviridis E-86. Four arabinoxylo-oligosaccharides and two glucuronoxylo-oligosaccharides were isolated from the enzymatic hydrolysate of the xylan by chromatography on a charcoal column, a Dowex 1-x8 column, a Toyo-pearl HW-40S column, and a LiChrospher 100 NH₂ column and on preparative paper chromatography. The results of the structural analyses of the saccharides showed that the isolated oligosaccharides had the structures of 3²--l-arabinofuranosyl-xylobiose, 3²--l-arabinofuranosyl-xylotriose, 3²--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylobiose, 3³--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylotriose, 2³--4-O-methyl-d-glucuronosyl-xylotriose, and 2³--d-glucuronosyl-xylotriose. From the structural analysis of the oligosaccharides derived from the xylan, kumaizasa xylan was concluded to be a kind of arabinoglucuronoxylan having not only stubs of singlel-arabinose and singled-glucuronic acid but also stubs of disaccharide units such as-d-xylopyranosyl-(1 2)-l-arabinofuranose.  相似文献   

Ingestion of water-soluble soybean fiber prevents osteopenia and hypercholesterolemia induced by ovariectomy in rats   总被引：2，自引：0，他引：2  

Mitamura R  Hara H  Aoyama Y  Takahashi T  Furuta H 《Journal of agricultural and food chemistry》2003,51(4):1085-1089

This study examined the effects of feeding water-soluble soybean fiber (WSSF), a highly fermentable dietary fiber with low viscosity, on intestinal calcium (Ca) absorption, bone mineral content, and serum total cholesterol levels using female Sprague-Dawley rats (5 weeks old) with or without ovariectomy (OVX). The rats in each group were fed a WSSF (50 g/kg of diet) or WSSF-free diet for 4 weeks. Ca absorption was higher in OVX rats fed the WSSF diet than in OVX rats fed the WSSF-free diet. Femoral Ca content in both sham and OVX rats fed the WSSF diet was higher than that in rats fed the WSSF-free diet. The serum total cholesterol levels were elevated after OVX compared with that in the sham rats, and this elevation was prevented by the WSSF diet. In conclusion, ingestion of WSSF prevented osteopenia and hypercholesterolemia induced by ovariectomy in rats.  相似文献   

单一重金属胁迫对灯心草生长及生理生化指标的影响   总被引：15，自引：0，他引：15  

孙健  铁柏清  钱湛  毛晓茜  杨佘维  青山勋  罗荣 《土壤通报》2007,38(1):121-127

通过盆栽试验研究了不同浓度处理水平的Cu、Cd、Pb、Zn、As五种重金属单一胁迫对灯心草生长及其生理生化特性的的影响。结果表明:种植灯心草土壤中的Cd、Pb、Cu三种重金属临界值可分别设定为10mg kg-1、100 mg kg-1、100mg kg-1。灯心草不适合在Zn污染的土壤中种植,土壤中As临界值尚需作进一步的研究来确定。各单一重金属胁迫对灯心草叶绿素的合成均有很大程度的抑制作用,剂量-效应关系明显。灯心草三种保护酶对于不同浓度处理水平重金属胁迫的响应不同:在土壤环境质量低浓度设置范围内三种酶有较好的协同效应能共同抵御重金属胁迫造成的膜伤害,表现出较强的自我调节能力。而在高浓度处理水平时,三种酶活性呈现不同的变化趋势。灯心草生理生化指标对重金属胁迫的响应存在元素种类之间的差异。各单一重金属对灯心草生长抑制及生理毒害效应大小排序为:Zn>As>Cu>Pb>Cd。  相似文献   

Effect of incubation temperature or maternal antibody on virus growth and mortality of embryonated chicken eggs inoculated with the B1 strain of lentogenic Newcastle disease virus     

S Yachida  S Aoyama  N Takahashi  Y Iritani  K Katagiri 《Avian diseases》1979,23(4):983-988

The effects of incubation temperature on virus growth and mortality patterns were studied in antibody-free chicken eggs inoculated with the B1 strain of Newcastle disease virus. Embryo mortality patterns did not differ much between 37, 39, and 41 C of incubation, although virus growth curves were higher at 39 C and 41 C than at 37 C. Below 35 C, embryo mortality was delayed, although from 48 hours after incubation the virus growth curves were similar to those at 37 C. In eggs with and without maternal antibody, virus titers were maximum 48 hours after incubation, although slightly higher in antibody-free eggs than in eggs with antibody whether the eggs were alive or dead. Eggs with maternal antibody had delayed mortality patterns.  相似文献