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21.
中国一年生野生大豆群体的遗传多样性研究   总被引:4,自引:0,他引:4  
选用来自全国各地的一年生野生大豆200 余份材料,从形态性状、等位酶标记和细胞器DNARFLP标记的遗传丰富度和遗传离散度两方面分析了中国野生大豆群体的遗传多样性.结果表明:中国野生大豆天然群体存在着遗传分化,各地理生态群体间的遗传多样性水平不同,南方群体最高,黄淮海群体次之,东北群体最低.南方为一年生野生大豆的遗传多样性中心,也可能是起源中心.  相似文献   
22.
Introduction D istillery w astew ater m ainly includes spent w ash, w hich is one of the m ost com plex, troublesom e industrial organic effluents. This kind of w astew ater has previously been treated aerobically after dilution w ith other w ash w aters.…  相似文献   
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Keiji Abe  Keiichi Tanaka 《Chemosphere》1997,35(12):2837-2847
Mono-, di- and trichlorophenol including different isomers were degraded by O3, O3 + UV and O3 + UV + Fe3+. Disappearance rates are nearly identical among three ozonations. Whereas TOC elimination was not completed by ozone alone. UV illumination accelerated TOC elimination rate and the addition of Fe3+ (O3 + UV + Fe3+) further accelerated it. TOC elimination rates among different chlorophenols were in the order of mono > di > tri. The effect of Fe3+ was largest on the degradation of trichlorophenol. Hydroxylated aromatics, organic acids, formaldehyde and acetone were detected as intermediates.  相似文献   
25.
K. Abe  J. Vannier 《Marine Biology》1995,124(1):51-58
Combined high-resolution video-recordings of live specimens, SEM and serial microtome sections were used to document the morphofunctional aspects of blood (hemolymph) circulation in Ostracoda, exemplified by the nektobenthic myodocopid Vargula hilgendorfii from Japan. The circulatory system is comprised of a single-chambered dorsal heart (pericardium, myocardium with two ostia), efferent vessels (aorta and secondary arteries) and an integumental afferent network of sinuses radiating from the adductor muscle area to a peripheral channel leading to heart. The heartbeat and the linear velocity of hemolymph in sinuses range from 0.5 to 6 times s-1 and 200 to 1000 m s-1, respectively. Hemocytes (10 to 17 m) of irregular shapes occur within the circulating hemolymph. This typical open circulatory system is found in most myodocope ostracodes and other crustaceans. It is totally absent in small (mostly <2 mm) ostracodes such as Podocopa. We conclude that the fluid convection of hemolymph augments the diffusion process of O2 in larger animals. Oxygen uptake is assumed to occur preferentially through the inner (posterior) surface of the carapace where hemolymph sinuses are best developed and in close contact with sea water. Hemocytes may be involved in coagulation processes as in other crustaceans (e.g. Decapoda). Integumental circulation, preserved as anastomosing features in fossil Ostracoda, is known from the early Palaeozoic through to the Recent.  相似文献   
26.
T Abe  H Saito  Y Niikura  T Shigeoka  Y Nakano 《Chemosphere》2001,45(4-5):487-495
An assay system using Daphnia magna embryos was applied to investigate the adverse effects of aniline derivatives. The data were compared with our previous data for chlorophenols. This new assay provides useful information to evaluate the toxicity of chemicals and the differences in sensitivity between the life stages. The effects of 15 aniline derivatives on embryonic development of D. magna embryos were determined. At the start of exposure, 2-6-h old eggs (between stages 1 and 2, round in shape, diameter approx. 400 microm), were used. In control and solvent control groups, embryonic development from an egg to a free-swimming animal proceeded completely within 3 days with more than 90% hatchability. Median effective concentrations (EC50s) to reduce the numbers hatched were determined and gross morphological abnormalities of hatched animals recorded. Anilines induced no obvious morphological abnormalities and no developmental delay although premature deaths occurred. However, they affected the number of embryos hatching in a dose-dependent manner. In addition, this embryo assay was more sensitive to aniline derivatives (except for aniline) than acute juveniles immobilization assay. Ratios of 48-h EC50 (juvenile)/3-day EC50 (embryo) for eight anilines were greater than 5.0. Particularly, the ratios of 4-methyl-, 4-ethyl- and 3-methylaniline were 77, 23 and 11, respectively. EC50s for embryos and juveniles were poorly correlated (r = 0.41). This indicated that the sensitivities of the two life stages were different to the effects of anilines. EC50s were poorly correlated (r = -0.097) with the log Kow (1-octanol/water partition coefficient). These results were compared with previous results for phenols.  相似文献   
27.
Concentrations of 22 elements (Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, total Hg (T-Hg), Pb) and organic Hg (O-Hg) were examined in the liver, kidney and brain of the Javan mongoose (Herpestes javanicus) and in liver of the Amami rabbit (Pentalagus furnessi) from Amamioshima Island in Japan. Relatively high levels of T-Hg levels (from 1.75 to 55.5 microg g-1 wet wt.) were found in the Javan mongoose. As for a comparison of hepatic T-Hg concentrations between the two areas, there was no significant difference between the Javan mongoose in Amamioshima and those in the Okinawa islands. In addition, T-Hg levels in the livers of the Amami rabbit were the same as in the livers of other herbivorous mammals. Taken together, it suggested that T-Hg accumulation in the livers of the Javan mongoose was not affected by the environment but by a specific physiological mechanism. The comparison of Hg and other heavy metal accumulations between terrestrial mammals (13 species, 61 individuals) including the Javan mongoose and marine mammals (18 species, 508 individuals) were also discussed.  相似文献   
28.
An alkaline comet assay and a micronucleus test were carried out on erythrocytes of the European chub, Squalius cephalus L., collected in spring and autumn in 2005 and 2006 at three sampling sites in River Sava, near Zagreb, Croatia. The results of comet assay showed the lowest genotoxic influence at the least polluted site, while higher DNA damage was observed at the polluted sites. Although the basal levels of DNA damage were elevated, a clear gradation of DNA damage was found due to pollution intensity in all sampling periods. The lowest cytogenetic damage as revealed by the micronucleus test (MNT) was observed as well at the least polluted site. High variations in MN frequency were observed between sampling periods, although the number of micronucleated erythrocytes was consistently the highest one at the polluted site. The comet assay as a biomarker of genotoxic effect exhibited higher sensitivity in discriminating the genotoxic capacity of studied polluted sites while the MNT was less sensitive. However, both tests should be used together in biomonitoring studies because they can reveal different aspects of DNA damage; comet assay, the early event of genotoxic exposure, and MNT, its final result as a mutagenic potential.  相似文献   
29.
In vitro reporter gene assays using vertebrate cell lines or yeast have been used for assessment of the estrogenic chemicals. However, estrogen receptor α (ERα)- and ERβ-mediated reporter gene system in fish has yet to be developed. In the present study, we developed an ERα- and ERβ-mediated reporter gene assay in fish and estimated estrogenic activities of 17β-estradiol (E2), p-nonylphenol (NP), bisphenol A (BPA), p,p′-DDE, and genistein (Gen) using the in vitro reporter assay. The activity was intensely induced by transfection with either ERα or ERβ expression plasmid under E2 or Gen administration, whereas it was significantly induced by transfection with ERα expression plasmid, but not with ERβ expression plasmid under NP administration. On the other hand, the activity was induced more intensely by transfection with ERα expression plasmid than ERβ expression plasmid under BPA or p,p′-DDE administration. These results indicate that there are obvious differences in the activity through ERα and ERβ among the estrogenic chemicals examined in vitro. Thus, the in vitro reporter assay provides an excellent system for elucidating the action mechanism of estrogenic chemicals in fishes. Physical and Chemical Impacts on Marine Organisms, a Bilateral Seminar Italy–Japan held in November 2004  相似文献   
30.
An axis is an undirected line where there is no reason to distinguish one end of the line from the other. Phenomena in nature that can be described as axial data are numerous. In this paper a method of trigonometric moments for the axial normal or axial von Mises distribution as an alternative to the method by Arnold and SenGupta (Environ Ecol Stat 13:271–285, 2006) is discussed. Sine-skewed axial Jones–Pewsey, von Mises and wrapped Cauchy distributions are introduced as special cases of a more general construction of skew axial distributions. As an example the methods are applied to a data set which consists of the orientations of logs on the floor of a primeval spruce forest.  相似文献   
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