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1.
串珠镰孢菌的孢子和细胞壁水解物可诱导棉花悬浮培养细胞产生反应性氧迸发。来自抗性品种豫棉8号的培养细胞表现为二次反应性摒迸发。培养细胞的生长状态,激发子浓度、反应介质中Ca^2+和K^+等金属离子含量、H^+-ATP酶的抑制剂(钒酸盐),NADPH氧化酶抑制剂和人工电子受体Fe(CN)6^3-均影响细胞的反应性氧迸发水平。  相似文献   

2.
通过在DCC(二环已基碳酰二亚胺)存在下用4β-氨基-4-去氧-4′-去甲表鬼臼毒与卤代苯甲酸缩合,合成了12个新的4β-卤代芳香酰胺基-4-去氧-4′-去甲表鬼臼毒衍生物(2~13).测定了这些化合物对KB,HCT-8,A-2780和HeLa-60细胞的杀伤效应(体外细胞试验).结果显示,这些化合物中大多数比目前临床使用的抗癌药物依托泊甙,即VP-16在HCT-8,A-2780和HeLa-60细胞的杀伤中有较强的效果.对这些化合物进行了大鼠肝微粒体脂质过氧化试验.结果显示这些化合物具有明显的抗脂质过氧化能力.用QSAR(定量的结构-活性相关关系)方法分析了该类化合物的结构和对KB,HCT-8和HeLa-60细胞抑制作用间的相互关系  相似文献   

3.
检测早孕蜕膜中淋巴细胞抗原的表达。以几种抗淋巴细胞表面标志的单克隆抗体,采用花环标记、碱磷酶抗碱磷酶(APAAP)法,对23例早孕蜕膜组织中的淋巴细胞进行测定。早孕蜕膜淋巴细胞中CD3+、CD4+、CD16+及B细胞百分率(x±s)分别为29.52±6.80%、23.60±4.80%、20.91±4.06%、1.07±1.00%、7.81±2.56%,CD4/CD8为1.2±0.2,CD3-淋巴细胞呈大颗粒淋巴细胞(LGL)形态。早孕蜕膜中存在较多CD3-、CD16-形态呈LGL的NK细胞,CD4+细胞与CD8+细胞的比值较正常外周血明显降低。  相似文献   

4.
温桂珍 《广西科学》1995,2(2):62-63
以巴西铁(Dracaena sanderiena)茎段为接种材料,MS为基本培养基,吲哚乙酸(IAA)、茶乙酸(NAA),2,4-二氯苯氧乙酸(2.4-D)、6-苄氨基嘌呤(6-BA)、6一糠基氨基嘌呤(6-FA)、吲哚丁酸(IBA)、生根粉(ABT1)、玉米素(ZT)为附加成分,进行诱导、分化、生根试验。诱导结果表明:IAA不起作用,2,4-D有较好的促进作用,0.5mg/L(2,4-D)+2mg/L(6-BA)组合,诱导率高达90%。分化结果表明:NAA、6-BA效果较好,6-FA作用不明显,lmg/LNAA+4ms/L(6-BA)+2ms/LZT组合,分化率最高.达81.1%。生根结果表明:MS+0.5mg/LNAA+0.5mg/L(6-FA),MS+0.4mg/LNAA+2mg/LIBA,MS+0.2mg/LNAA+0.1mg/L(6-FA)+ABT1三种培养基均发根,生根率70%以上,根粗,但有点脆,若培养基中加入活性碳产生的根则细而韧。  相似文献   

5.
对小鼠肺腺癌细胞系(LA-795)高、低转移亚系(LA-795-C_6和LA-795-C_7)体外培养第20及30代细胞染色体G显带核型进行比较,结果高转移亚系细胞染色体众数较低转移亚系细胞具有不稳定性的特点,表明转移潜能的差异和遗传物质的稳定程度密切相关.高、低转移亚系出现相同及不同的标志染色体和异常染色体,其中,高转移亚系出现标志染色体8种及del(8)q ̄(ter),del(12)q ̄(ter),11P ̄+,13P ̄+,tri(2M4),dic(2M5),M6:7q ̄+?;而低转移潜能亚系出现标志染色体12种及del(8)q ̄(ter),del(12)q ̄(ter),r(15),dic(M6;2M7),M8:7q ̄_?t(2:2),t(2:15),t(15:M10),t(15:M11),t(5:M12).表明来源于同一母系而转移潜能不同的亚系染色体核型具有本质上的差异,转移潜能与其密切相关.另外,分析低转移亚系出现t(2:2);t(C2:15)t(15:M10);t(15:M11); t(5:M12);r(15)等现象,推测高、低转移潜能亚系细胞可能存在本身H-2系统及CD44抗元表达的差异,这很可能  相似文献   

6.
2种无银保鲜剂对切花菊的保鲜效应   总被引:3,自引:0,他引:3  
杨振德  梁机 《广西科学》1999,6(2):154-156
研究保鲜剂(2%蔗糖+50mg/L柠檬酸+100mg/L8-羟基喹啉+1mg/L6-BA)和保鲜剂2号(2%蔗糖+50mg/L水杨酸+100mg/L8-羟基喹啉+1mg/L6-BA)对“黄秀凤”切花菊(Chrysanthemummorifoliumcv.“HuangXiufeng”)瓶插寿命和瓶插期间花枝的水分状况,叶绿素和可溶性蛋白质含量以及过氧化物酶(POD)活性等生理延长2d但与延长花冠寿命  相似文献   

7.
本文研究了1-苯基-3-甲基-4-(α-呋喃甲酰基)-5-吡唑酮(HA)单独萃取Y(Ⅲ)及其与二苯亚砜(DPSO),磷酸三丁酯(TBP)或三辛基氧膦(TOPO)协同萃取Y(Ⅲ)的行为。确定了萃合物的组成分别为YA_3,YA_3·DPSO,YA_3·TBP和YA_2(NO_3)·2TOPO.算得萃取平衡常数分别为:logK_(A(HA))=-6.86,1ogK_(AB(HA+DPSO))=-3.89,logK_(AB(HA+TBP))=-2.53和logK_(AB(HA+TOPO))=5.13.  相似文献   

8.
绵枣儿两个不同居群的核型研究   总被引:2,自引:0,他引:2  
本文报道了安徽省芜湖和琅琊山产绵枣儿Scilla scilloides(Lindl.)Druce的染色体数目和核型,其结果如下:芜湖材料有两个细胞型:AA和BB型,A和B分别代表A染色体组(x=8)和B染色体组(x=9)。细胞型I;2n=16+1Bs=6m+2sm+8st+1Bs;细胞型Ⅱ:2n=18+1Bs=8m+2sm+8st+1Bs,二者均属Stebbins“3B”核型。琅琊山材料仅发现一个细  相似文献   

9.
F~-离子和Ti~(4+)离子在CaO-Al_2O_3-SiO_2系玻璃晶化时的作用   总被引:3,自引:0,他引:3  
在CaO-Al2O3-SiO2(CAS)系玻璃中单独引入F-离子或Ti4+离子,以及同时引入F-离子和Ti4+离子,通过DTA(差热分析)、XRD(X-射线衍射)、Raman、XPS(光电子能谱)和SEM(扫描电镜)方法进行了研究。结果表明在CAS系玻璃中一部分F-离子取代非桥氧离子处于玻璃网络内部,另一部分F-离子处于玻璃网络间隙,F-离子能促使CAS系玻璃分相,在稍高于Tg的某一温度热处理时,CaF2晶体首先从玻璃中析出;Ti4+离子对玻璃晶化影响不大,在稍高于Tg的某一温度热处理时,加Ti4+离子和不加Ti4+离子的玻璃首先析出的晶相均是钙长石(CaAl2Si2O8);在CAS系玻璃中同时引入F-离和Ti4+离子时,在稍高于Tg的某一温度热处理后首先析出的晶体是CaF2和钙长石(CaAl2Si2O8),F-离子和Ti4+离子混合使用能更好地促进CAS系玻璃的晶化。  相似文献   

10.
茴香原生质体培养研究   总被引:1,自引:0,他引:1  
以茴香(FoeniculumvulgareL.)幼苗茎切段在MS附近2,4-D1mg/L、6-BA0.5mg/L的培养基上诱导产生愈伤组织,经4~5次继代后形成胚性愈伤组织。将胚性愈伤组织转至MS+NAA1mg/L+2,4-D0.5mg/L+6-BA0.25mg/L的液体培养基中培养,形成胚性细胞悬浮系。悬浮细胞在含有1.5%纤维素酶、1%果胶酶、0.5%蜗牛酶的混合酶液中酶解得到大量的原生质体,原生质体用修改的KM8P培养基中做液体浅层培养。2天后细胞发生一裂,两个月后形成0.5~1mm大小的小愈伤组织,转入含琼脂糖的固体培养基中3周后形成2~3mm的愈伤组织  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.
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   

13.
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   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
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   

16.
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   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
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   

19.
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   

20.
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