Cr6+污染对水鳖的超微结构及菱、

Cr6+污染对水鳖超微结构的影响主要表现在胞间连丝呈现不同程度的断裂;细胞核出现各种各样的变形;叶绿体膨胀,其基粒解体.细胞损伤程度与Cr6+培养浓度呈正相关.Cr6+对水鳖、菱、莼菜和黑藻这几种水生高等植物的细胞膜影响主要表现在质壁发生分离,质壁之间有黑色颗粒存在.在做生理验证时发现处理组的膜脂过氧化产物丙二醛(MDA)和超氧阴离子(O2)均高于对照.     

Cr6+污染对水鳖的超微结构及菱、莼菜、黑藻细胞膜的影响

Cr⁶⁺污染对水鳖超微结构的影响主要表现在:胞间连丝呈现不同程度的断裂;细胞核出现各种各样的变形;叶绿体膨胀,其基粒解体。细胞损伤程度与Cr⁶⁺培养浓度呈正相关。Cr⁶⁺对水鳖、菱、莼菜和黑藻这几种水生高等植物的细胞膜影响主要表现在:质壁发生分离,质壁之间有黑色颗粒存在。在做生理验证时发现处理组的膜脂过氧化产物丙二醛(MDA)和超氧阴离子(O₂)均高于对照。     

Cr^3＋胁迫对苦草叶片活性氧清除系统和叶细胞超微结构的影响

研究了不同浓度Cr^3＋胁迫对苦草[Vallisneria natarts（Lour．）Hara]叶片活性氧清除系统及细胞超微结构的影响。结果表明,随Cr^3＋浓度的提高（0．5-15．0mg·L^-1）,苦草叶片中O2^-·和MDA含量、SOD和POD及CAT活性均呈现先上升后显著下降的变化趋势,且在10．0和15．0mg·L^-1 Cr^3＋胁迫条件下显著低于对照（P〈0．05）。在1．0mg·L^-1Cr^3＋胁迫条件下,O2^-·的含量达到最高（0．96 OD·g^-2）;在2．0mg·L^-1Cr^3＋胁迫条件下,MDA含量和SOD、POD及CAT活性最高。随Cr^3＋胁迫浓度的提高,苦草叶片细胞超微结构受损程度逐渐加深,导致核仁和高尔基体消失;线粒体脊突膨胀,线粒体膜受损并出现囊泡状结构;叶绿体变形、类囊体膨胀受损并最终导致叶绿体破损。表明高浓度Cr^3＋胁迫对苦草叶片细胞产生了不可逆的伤害。     

白术提取物对六价铬致人外周血淋巴细胞 抗突变作用研究

目的：探讨白术提取物抗六价铬的致突变作用。方法：采用人外周血淋巴细胞程序外DNA合成（UDS）试验检测了0．03g、0．015g和0．0075／ml白术提取物对重铬酸钾（含Cr^6＋0．31ug/ml）所致淋巴细胞程序外DNA合成的影响。同时检测白术提取物与重铬酸钾的加入顺序对UDS的影响。结果：阳性对照（重铬酸钾,含CCr^6＋0.31ug/ml）组CPM值显著高于阴性对照（蒸馏水）组,P〈0．01。白术提取物与重铬酸钾同时加入以及两者间隔2h先后加入均显示白术提取物浓度与CPM值呈显著负相关（P〈0.05）,在上述不同加入方法中,白术提取物的各浓度均显示CPM值显著低于阳性对照。结论：白术提取物具有抑制Cr^6＋的致突变作用。     

正加速度（＋Gz）暴露对冠脉不同程度狭窄猪血浆CK-MB和IL-6变化的影响研究

目的：观察正加速度（＋Gz）暴露处理后不同冠脉狭窄程度猪的血浆肌酸激酶同工酶（CK-MB）和白介素-6（IL-6）水平的变化特点,探讨心脏的危害,评估飞行员的飞行。方法：（1）20头巴马小型猪,在胸腔镜直视下手术丝线永久性结扎左前降支近端建立轻度（狭窄程度20-49%）、中度（狭窄程度50-69%）和重度（狭窄程度≥70%）狭窄的冠状动脉狭窄模型;（2）各组小型猪进行＋Gz暴露,分别观察其最大＋Gz加速度耐受值;（3）各组小型猪分别在其最大＋Gz加速度暴露处理前后1 min留取静脉血和分离血浆,测定CK-MB及IL-6的含量。结果：（1）各组小型猪最大＋Gz加速度耐受值分别为：①正常对照组：＋8 Gz;②轻度狭窄组：＋8Gz;③中度狭窄组：＋6 Gz;④重度狭窄组：＋5 Gz;（2）最大耐受＋Gz加速度暴露对各组小型猪血浆CK-MB及IL-6的影响差异有统计学意义（P〈0.01）,同时,在分别经过最大耐受＋Gz加速度暴露处理后,冠脉中度和重度狭窄模型猪血浆CK-MB和IL-6的浓度较正常对照组均显著升高（P〈0.01）,轻度狭窄组则升高不明显（P〉0.05）。结论：（1）＋Gz暴露对冠脉不同程度狭窄小型猪血浆CK-MB和IL-6水平的影响不同,狭窄程度越重,影响越大。（2）轻度狭窄模型猪在＋Gz暴露下血浆CK-MB和IL-6的浓度改变与正常对照组相似,提示冠脉轻度狭窄的飞行员可以继续飞行。     

模拟酸雨条件下Pb2+和Cr6+对蕹菜光合作用及品质的影响

以蕹菜（Ipomoea aquatica Forsk．）为供试对象,通过盆栽试验,研究了不同酸度模拟酸雨（AR）条件下,Pb^2＋和Cr^6＋对其光合作用、营养品质及食用安全性的影响。结果表明：酸雨条件下,重金属对蕹菜叶片光合作用和品质的胁迫表现为Pb〉Pb＋Cr〉Cr;随酸度增加,AR＋Pb和AR＋Pb＋Cr处理的危害性显著增加,pH=3．5时,AR＋Pb＋Cr处理的胁迫性明显大于其他处理水平,对蔬菜造成伤害;3个光合作用参数均随酸雨酸度增加有不同程度的下降,但对胁迫的敏感性存在差异;pH〈5．6时,蕹菜中蛋白质和游离氨基酸含量与pH值呈正相关;随酸度增加,可溶性糖含量增加,而还原性糖含量下降,表现出对环境胁迫的应激反应;除了Cr污染处理外,Pb污染和Pb＋Cr污染都能显著促进蕹菜中硝态氮积累,其含量随酸雨酸度上升而增加;蕹菜中Pb和Cr存在竞争吸附作用,且随着酸雨酸度下降,蕹菜对2种重金属的富集有加快趋势。     

六价铬对水绵生长的毒性效应

为研究六价铬（Cr^6＋）对水绵（Spirogyrasp．）的毒性效应和水绵对六价铬的毒性响应,实验设置5个暴露组（4、6、8、10和12mg／L）和1个对照组。结果表明：96h后各暴露组对水绵的生长均有抑制作用,铬浓度越高,藻细胞叶绿素a越低,显示出较明显的剂量一效应关系;六价铬对水绵的96h的Ec。值为7．25mg／L。细胞浸出液电导率在低浓度（4～6mg／L）组上升较缓慢,在高浓度组（8～12mg／L）上升显著;丙二醛（MDA）累积含量在Cr6＋≥4mg／L时,累计含量上升较高（P〈0．01）,当Cr^6＋≥8mg／L时,累积含量上升较少。水绵细胞浸出液电导率与MDA存在显著正相关（P〈0．05,r=0．891）。水绵细胞浸出液电导率和MDA含量与六价铬浓度分别存在显著（P〈0．05,r=0．951）和极显著（P〈0．01,r=0．977）的非线性的毒性响应关系。     

铬对重金属去除菌影响的研究

考察了Cr^6 浓度和培养时间对4株重金属去除菌致死率的影响、重金属去除菌除铬性能的稳定性、吸附铬前后胞内外的变化、Cr^6 对胞内可溶性还原糖含量的影响以及多种因素对重金属去除菌毒性,初步探讨了重金属去除菌的抗Cr^6 机理。实验结果表明,4株实验菌的致死率随培养时间的变化趋势都是先升高后降低,最后再升高;假丝酵母的可驯化性较好;掷孢酵母7-3对高浓度Cr^6 的耐受性最好;Cr^6 对4株实验菌的各种代谢过程有一定影响;扫描电镜,透射电镜及原子力显微镜等实验结果表明：产朊假丝酵母的除铬机理是表面吸附和胞内积累并存;在正交实验中,Cr^6 浓度、pH、培养时间、N源、C源、吸附时间等6个因素对4株实验菌的影响各不相同。     

铝、镉对小麦幼苗生长的影响及其DNA损伤效应研究

本研究旨在探索Al^3＋、Cd^2＋对小麦幼苗生长的影响及其DNA损伤效应。结果表明：（1）所试浓度Al^3＋、Cd^2＋不仅不同程度抑制2d龄和12d龄幼苗根系和地上部分的生长,而且表现明显的DNA损伤效应;（2）除Al^3＋对幼苗地上部分鲜重、干重的影响及Cd^2＋对幼苗根系生长速率的影响外,其余生长指标显示2d龄幼苗比12d龄幼苗对Al^3＋、Cd^2＋更敏感,这与导致2d龄幼苗DNA损伤的Al^3＋、Cd^2＋浓度明显低于12d龄幼苗的结果一致。研究结果表明,DNA损伤可能是Al^3＋、Cd^2＋抑制2d龄和12d龄小麦幼苗生长的重要原因之一。     

Pb2+、Cd2+对3种水生动物致毒效应影响的比较研究

在特定时间（12、24、48、72h）内,研究了Pb^2＋和Cd^2＋对草履虫（Paramecium caudatum）、三角涡虫（Dugesia japonica）和中华圆田螺（Cipangopaludia viviparrus）3种水生动物的单一和联合毒性效应.结果表明：在同等条件下,Cd^2＋对三者的致毒效应都明显强于Pb^2＋;3种动物中,草履虫最敏感,而圆田螺耐受能力最强;随单一毒物浓度的增大以及暴露时间的延长,两者的致毒效应都显著增大,表现出明显的浓度—效应和时间—效应关系;二者复合作用时,对3种动物的致毒效应主要表现为与二组分的浓度比例有关.复合致毒效应也表现出了明显的浓度—效应关系,并且浓度和暴露时间的交互作用对3种水生动物毒性都有显著的影响.     

Reliability of Analyses of Hg,Fe, Ca,K, P,pH, Alkalinity,Conductivity, Hardness and Colour from Lakes

The aim of this report has been to present results concerning analytical quality controls of Hg analysis of fish and sediment, analyses of Fe, Ca, total-P, K, pH, alkalinity, conductivity, colour and hardness (Ca + Mg) of lake water samples. Despite the fact that these are standard parameters in many regular water control programs, there are major differences in the reliability with which these parameters can be determined. The focus here is on an overall inter-laboratory comparison between the parameters. Six laboratories have been involved in the analysis. Selected results: pH gives the lowest (average) relative standard deviation (error), about 2 %; conductivity gives an error of about 5–7 %; alkalinity yields an average error of as much as 13–25 %, which is the largest among the parameters studied here; colour also gives a high error, 9–15 %; hardness gives a relative standard deviation of about 6–7 %. Of the other parameters (i. e., Hg, Fe, Ca and P), Hg gives the best reliability and Fe and P the lowest. To have knowledge of the reliability of the analytical data is of paramount importance in most control programs and research projects.     

Distribution of N,P, K,Ca, Mg,S, Zn,Fe, Mn and Cu in groundnut

Summary Concentration of N, P, K, Ca, Mg and S in summer groundnut crop was higher than in kharif while Zn, Fe, Mn and Cu contents were higher in summer crop. Kernel's N, P and Zn; Leaflet's Ca and Mn; Stem's K and Fe; Root's S and Cu and Petiole's Mg contents were highest. Shell's N, P, K, Mg, S, Zn and Cu; Kernel's Ca, Fe and Mn contents were the least. N, P, K, S, Zn and Cu concentrations decreased linearly as the crop grew. Ca, Mg, Fe and Mn concentrations did not display any distinct pattern. Ca concentration was positively correlated with pod yield in both the seasons.     

Uniform hypothesis of cell behavior--movement, contact inhibition of movement, adhesion, chemotaxis, phagocytosis, pinocytosis, division, contact inhibition of division, fusion.

The cell has been represented as a charged liquid drop. Contrary to the DLVO-theory, the effect of the surface potential upon the value of the interfacial tension of the cell membrane has also been taken into consideration. The cell membrane has visco-elastic properties and its constituents may move against each other. Cell movement is caused by the appearance of a small number of the electrically charged constituents of the cell membrane on the leading edge of the cell. This produces a local decrease in the surface tension and the cell membrane expansion. At the moment of contact between two cells proton transfers occur between the strongly negatively charged microvilli of one cell and the body of the other, analogous to a condenser breakdown. This, through the effect on the surface tension, causes contact inhibition of movement. The distribution of the proton dissociable groups modifies the interaction between the cells (differentiation) and between the cell and the substratum (adhesion). Adsorption of the charged compounds at the surface of the cell membrane, decreasing the surface potential and increasing the surface tension, causes the phenomena of chemotaxis, phagocytosis and pinocytosis. Cell division, considered in the terms of the surface energy, requires an adequate supply of considerable quantities of energy inversely proportional to the surface potential value. In case of a reduction of the distance between the cells, their surface potential and the energetic barrier of the cell division processes increases, and causes contact inhibition of cell division. Due to their high charge, division of neoplastic cells is inhibited much later than division of normal cells, or is completely ininhibited due to geometric conditions. Fusion of the cell membrane in the intra-cellular and intercellular processes is a reverse process in relation to the cell division.     

The effect of malathion,diazinon, and various concentrations of zinc,copper, nickel,lead, iron,and mercury on fish

Acute and chronic toxicity tests for malathion, diazinon, copper (Cu), mercury (Hg), lead (Pb), zinc (Zn), nickel (Ni), and iron (Fe) were conducted. Mortalities ofBarilius vagra andCyprinus carpio (common carp) were variable but LC50-96 hr were similar for pesticides. AdultB. vagra seem to be more sensitive to malathion than juvenile carp. Both juvenile carp and adultB. vagra were extremely sensitive to diazinon. Long-term exposure to pesticides modified morphology and behavior. The LC50-96 values for Cu, Hg, and Pb were 0.3, 0.16, and 0.44, respectively, for smaller fish and 1.0, 0.77, and 1.33, respectively, for larger fish. Replicate LC50 values for Zn, Ni, and Fe were somewhat variable, and for these metals, the size of the fish seemed to affect response because LC50 values increased as fish size increased. Cooper, Pb, Zn, and Fe residues following exposure to sublethal concentrations of these metals for 15 d were significantly greater in whole juvenile common carp than in controls.     

The Effect of Age and Gender on Al, B, Ba, Ca, Cu, Fe, K, Li, Mg, Mn, Na, P, S, Sr, V, and Zn Contents in Rib Bone of Healthy Humans

The effect of age and gender on major, minor, and trace element contents in the intact rib bone of 80 relatively healthy 15–55-year-old women and men was investigated. Contents or upper limit of contents of 16 chemical elements in the rib bone were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Mean values (M?±?SΕΜ) for the mass fraction of Ba, Ca, Cu, Fe, K, Li, Mg, Na, P, S, Sr, and Zn (milligram per kilogram of dry bone) were as follows: 2.54?±?0.16, 171,400?±?4,050, 1.35?±?0.22, 140?±?11, 1,874?±?71, 0.049?±?0.011, 2,139?±?38, 5,378?±?88, 75,140?±?1,660, 1,881?±?51, 291?±?20, and 92.8?±?1.5, respectively. The upper limits of contents of Al, B, Mn, and V were <7.20, <0.65, <0.36, and <0.03, respectively. Statistically significant tendency for the Ca, Mg, and P content to decrease with age was found in the human rib bone, regardless of gender. The mass fraction of Fe in the male rib bone increases with age. It was shown that higher Ca, Mg, Na, P, and Sr mass fractions as well as lower Fe content were typical of female ribs as compared to those in male ribs.     

Further studies of the sieve-element plastids of theCaryophyllales includingBarbeuia,Corrigiola, Lyallia,Microtea, Sarcobatus,andTelephium

The sieve-element plastids of 69 species of theCaryophyllales were investigated by transmission electron microscopy. All contained the specific subtype-P3 plastids characterized by a peripheral ring of protein filaments. The presence or absence of an additional central protein crystal and their shape being either polygonal or globular as well as the average sizes of the sieve-element plastids are useful features in the characterization of some families.—Barbeuia contains sieve-element plastids that confirm its placement within thePhytolaccaceae. Lyallia differs fromHectorella by including small starch grains in their sieve-element plastids, which otherwise by their globular crystals negate a closer connection to theCaryophyllaceae. The lack of a central protein crystal in its form-P3fs plastids placesMicrotea best within theChenopodiaceae. Sarcobatus, a so far uncontested member of theChenopodiaceae, contains form-P3cf plastids, i.e., including a central crystal not found elsewhere in this family.Telephium andCorrigiola, shifted back and forth betweenMolluginaceae andCaryophyllaceae, have form-P3cf(s) plastids with a polygonal crystal which favor their placement within theCaryophyllaceae.     

Translocation of radionuclides of Co, Zn, Se, Rb, Y, Tc, and Re into organs of tomato plant via roots

The translocation of the radionuclides of Co, Zn, Se, Rb, Y, Tc, and Re into red and green fruits, flesh, seeds, rind, calyxes, flower, leaves, and stems via the root of the tomato plant at two different growth stages was studied by a multitracer technique. The contents (%/g) of Co, Zn, Se, and Y in the roots were the highest among the organs, but only small amounts of them were translocated into the aerial parts after 5 d cultivation with a multitracer. In contrast, Rb, Tc, and Re showed rapid translocation into the stems and leaves from the root. In the plants cultivated for 95 d with a multitracer, Zn, Se, and Rb distributed in all of the organs, Co in the organs except for flowers, and Y, Tc, and Re in the limited organs. The translocation ratio of the elements for the edible part of the plants cultivated for 95 d decreased in the order of Rb>Zn>Co≈Se>Tc≈Y>Re. The transfer factor of the elements for tomato fruit was determined to be in the range of 10⁻⁵–10⁻². The characteristic translocation behavior of the elements gives us fundamental information on the assessment of pollutant uptake by the tomato plant.