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1.
用不同浓度的Hg^2 处理豌豆种子,研究其对种子活力、幼苗生长及生理指标的影响.结果表明,Hg^2 能降低种子活力,抑制幼苗生长,当Hg^2 浓度为10^-5,10^-4,10^-3mol/L时,种子活力指数分别比对照组降低了25.08%,51.05%和76.11%,单株鲜重降低19.64%,42.86%和67.86%.随Hg^2 浓度的升高,幼苗根系活力和叶片硝酸还原酶活性降低,叶绿素和可溶性蛋白质含量下降,当Hg^2 浓度为10^-4,10^-3mol/L时,根系活力分别下降16.98%和48.58%,硝酸还原酶活性分别下降16.06%和22.70%,叶绿素含量分别降低19.55%和13.69%,可溶性蛋白质含量分别降低19.28%和22.25%;豌豆叶片膜脂过氧化产物丙二醛(MDA)含量增加,Hg^2 浓度为10^-3mol/L时,MDA的含量比对照组增加85.69%;超氧化物歧化酶(SOD)活性先升后降,当Hg^2 浓度为10^-5mol/L时,SOD活性达到最大,比对照组提高20.0%;过氧化物酶(POD)活性升高,过氧化氢酶(CAT)活性降低,当Hg^2 浓度为10^-3mol/L时,POD活性比对照组提高96.31%,CAT活性比对照组降低21.80%.随Hg^2 浓度的升高,根系过氧化物同工酶的表达受到抑制.  相似文献   

2.
温州薯蓣贮藏期间生理生化指标的变化   总被引:2,自引:0,他引:2  
对浙江瑞安真薯贮藏期间含水量、电导率和紫外吸收值、褐变度、总酚含量、PPO、POD、SOD活性和MDA含量的变化进行了研究。结果表明:随着贮藏时间的延长,浙江瑞安真薯含水量下降,电导率和紫外吸收值增大,褐变度、总酚含量和MDA含量不断增加,PPO、POD和SOD活性先升后降.  相似文献   

3.
锗对铁皮石斛原球茎的生长及抗氧化酶系的影响   总被引:4,自引:0,他引:4  
研究了不同浓度的锗(GeO2)对组培铁皮石斛原球茎的鲜重、可溶性蛋白质、叶绿素含量以及保护酶系统(SOD,CAT,POD)活性的影响.结果表明:适宜浓度的GeO2(5.00mg/L)能够显著增加铁皮石斛原球茎的鲜重,提高可溶性蛋白质和叶绿素含量,使SOD、CAT活性明显升高,而POD的活性则呈现缓慢的下降趋势.由此可见,培养基中添加5.00mg/L的锗时,对铁皮石斛原球茎的生长是有明显促进作用的.  相似文献   

4.
氨氮胁迫对背角无齿蚌三种酶活性的影响   总被引:1,自引:0,他引:1  
程剑  胡宝庆  饶育才 《江西科学》2008,26(6):887-890
本研究测定了在不同浓度氨氮胁迫下背角无齿蚌(Anodonta woodiana Lea)血清和肝胰腺中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)及溶菌酶(LSZ)活性的变化。结果表明,血清SOD活性在氨氮浓度为10mg/L时最低,之后随浓度的增加而上升,而肝胰腺SOD活性在氨氮浓度为2.5mg/L-10mg/L时随氨氮浓度增加而上升,当浓度为10mg/L时达到最大值,之后随浓度的增加其活性有所下降,但仍略高于对照组;在氨氮浓度为2.5mg/L~20mg/L时,肝胰腺CAT活性明显低于对照组,在浓度为2.5mg/L时为最小值,此后略有回升,在浓度为40mg/L时高于对照组,而血清CAT活性明显下降,在浓度为40mg/L时下降至最小值;肝胰腺LSZ活性随氨氮浓度增加成起伏变化,在氨氮浓度为10mg/L时达到最小值,之后明显上升,当浓度为20mg/L时达到最大值,而血清LSZ活性在氨氮浓度为2.5mg/L-10mg/L时与对照差别不大,在浓度为20mg/L时下降到最低值,在浓度为40mg/L时明显升高并达到最大值。  相似文献   

5.
通过萌发试验和盆栽试验,研究了不同浓度的硝酸钐溶液对白术的种子活力、丙二醛(MDA)含量、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性、叶绿素含量、光合速率等一系列生理生化指标的影响.结果表明,用20、30 mg.L-1的硝酸钐溶液浸种,使白术种子的发芽率和活力指数增加,白术幼苗的MDA含量、SOD和POD活性降低;用100 mg.L-1以下质量浓度的硝酸钐溶液喷施白术植株叶面,使其叶绿素含量增加,MDA含量减少,POD、SOD活性下降;当硝酸钐质量浓度达到300 mg.L-1时,白术叶片的POD、SOD活性和MDA含量增加.  相似文献   

6.
利用不同质量分数PEG-6000溶液,对牛膝菊(Galinsoga parviiflora)植株(株高30-40cm)进行干旱胁迫处理,研究了其叶片MDA(丙二醛)和可溶性蛋白含量、SOD(超氧化歧化酶)及POD(过氧化物酶)活性.结果表明,随着干旱胁迫强度增加,MDA含量、sOD活性和POD活性均呈现先上升后下降的趋势.PEG质量分数为20%时,MDA含量、SOD活性和POD活性达到最大值;PEG质量分数为15%时,可溶性蛋白含量达到最大值;PEG质量分数达到25%时,MDA含量、可溶性蛋白含量、SOD活性和POD活性降低.不同PEG质量分数处理,MDA含量、SOD活性、POD活性(除5%PEG外)均高于CK,但差异不显著(P〉0.05),而不同PEG质量分数处理下可溶性蛋白的含量均低于CK,差异也不显著(P〉0.05);随着干旱胁迫时间的延长,在不同PEG质量分数处理下,牛膝菊叶片MDA含量、SOD活性显著增加,可溶性蛋白含量显著减少,而POD活性具有明显阶段性变化:0~24h时间段,10%~20%PEG处理组POD活性呈递增趋势;24~48h时间段,10%~20%PEG处理组POD活性下降显著;48-72h时间段,10%~20%PEG处理组POD活性变化不明显,25%PEG处理组和CK的POD活性上升显著.  相似文献   

7.
研究了Hg^2+对茭白(Zizania latifolia Turcz.)体内共生的茭白黑粉菌(Ustilago dctdenta P.Henn.)的影响.对不同浓度Hg^2+胁迫下茭白黑粉菌在幼茎中的分布状态进行了解剖观察,分析了在此过程中的MDA含量、可溶性蛋白含量、SOD活性和POD活性等一系列指标.试验结果表明,2mg/L以上的Hg^2+胁迫能导致茭白黑粉菌的消亡,导致茭白茎尖不能膨大.  相似文献   

8.
以0.1、1和10mg/L3个浓度的多环芳烃萘和芘室内栽培红树植物秋茄(Kandelia candel)幼苗,培养基海水盐度15,培养期60d,以不加污染物培养为对照,分析了萘和芘对秋茄幼苗膜透性及抗氧化酶活性的影响.结果表明:在0.1mg/L萘和芘的环境胁迫对秋茄幼苗叶片细胞膜透性影响不明显,而浓度达1mg/L及以上水平则随着萘和芘浓度的增加叶片细胞膜透性显著增加.低浓度萘和芘(0.1mg/L)的环境胁迫对幼苗叶片、根尖超氧化物歧化酶(SOD)和过氧化物酶(POD)活性影响不明显;高浓度芘和萘(10mg/L)的环境胁迫下,秋茄幼苗叶片、根尖POD和SOD活性与对照组相比均显著提高.萘和芘胁迫诱导了秋茄幼苗抗氧化酶SOD和POD活性增加,其中根尖抗氧化酶活性增加的幅度明显大于叶片.  相似文献   

9.
硒对铁皮石斛拟原球茎生长及抗氧化系统的影响   总被引:1,自引:0,他引:1  
通过在培养基中添加Na2SeO3研究不同浓度硒对铁皮石斛组织培养拟原球茎的生长及抗氧化系统的影响.结果表明:适量加硒(≤0.2 mg/L)促进了拟原球茎的增殖生长,而高浓度硒(0.2 mg/L)则抑制了增殖,并且发现拟原球茎生长的最佳硒浓度为0.05 mg/L.低浓度硒(≤0.05 mg/L)显著增强了拟原球茎SOD、CAT、GSH-PX活性,而使POD活性降低、O2-产生速率变小,MDA含量明显下降;硒浓度过高(0.1 mg/L),SOD、CAT、GSH-PX活性被抑制,POD活性升高,O2-产生速率变大,MDA含量大幅上升.总之,适量加硒可增加产量,提高机体抗氧化能力.  相似文献   

10.
采用盆栽控水试验,研究了水分胁迫下我国亚热带地区森林演替过程中的重要树种木荷(Schima superba)和白楸(Mallotus paniculatus)的幼苗叶片叶绿素、类胡萝卜素、SOD活性、POD活性、脯氨酸和MDA含量的变化.结果表明:在干旱胁迫下,白楸叶片SOD活性、POD活性、脯氨酸和MDA含量在22%土壤相对含水量下均出现剧增,而Chla、Chlb和Car含量在22%的土壤相对含水量下则均出现降低;在同样的干旱胁迫下,木荷叶片SOD活性、POD活性和脯氨酸含量在19%的土壤相对含水量下才出现增加,而Chla、Chlb和Car含量则变化不大.在轻度淹水胁迫下,白楸叶片SOD活性、POD活性、脯氨酸和MDA含量基本呈增加趋势,而Chla、Chlb和Car含量星降低趋势;木荷叶片SOD活性、POD活性和脯氨酸含量在同期规律不明显.相关分析表明,白楸叶片SOD活性同脯氨酸含量变化呈显著正相关(r=0.815,P〈0.05)和MDA含量的变化呈极显著正相关(r=0.932,P〈0.01).由此说明,水分胁迫下,白楸比木荷敏感,木荷的耐受力强于白楸.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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