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1.
桑黄菌质多糖体外抑瘤及抗环磷酰胺致突变的作用   总被引:5,自引:0,他引:5  
采用MTT法研究桑黄固态发酵菌质多糖(PISPS)对肝癌细胞(HepG-2)、乳腺癌细胞(MCF-7)生长的抑制作用,测定出多糖对细胞生长的最高抑制率为59.18%、55.39%,半数抑制浓度为196.9、162.5μg/mL,且随药物浓度的增加抑制率有增大的趋势,与正常组比较作用较为显著(P〈0.05);选用小鼠骨髓嗜多染红细胞微核试验和小鼠精子畸形试验,对多糖的抗环磷酰胺(CP)致突变作用进行评价,结果表明桑黄菌质多糖使环磷酰胺诱发的细胞微核率和精子畸形率明显降低(P〈0.01).  相似文献   

2.
目的探讨有机磷农药敌百虫(dipterex,Dip)和敌敌畏(DDV)联合染毒对雄性小鼠生殖细胞的毒性作用。方法选择雄性小鼠32只,随机分为4组(3个染毒组和1个对照组)每组8只。染毒组小鼠每天分别给予2、10、50ms/kS剂量Dip和2、10、50mg/kg剂量DDV,经口染毒;对照组给予等容积的生理盐水。每天每只小鼠染毒1次,连续染毒27d。首次染毒后35d处死小鼠,观察精子数量、精子活率、精子畸形率及骨髓细胞微核率的变化。结果Dip、DDV联合染毒中、高剂量组精子数量、精子活率均低于对照组,精子畸形率、骨髓细胞微核率均显著高于对照组,差异具有统计学意义,并呈剂量一反应关系。结论Dip、DDV联合染毒可引起雄性小鼠生殖细胞的遗传损伤,导致生殖毒性效廊.并具有致突变作用。  相似文献   

3.
苯酚和邻甲酚的遗传毒理学研究   总被引:4,自引:4,他引:0  
采用小鼠骨髓细胞微核试验及人外周血淋巴细胞、小鼠睾丸生殖细胞、鲫鱼红细胞慧星试验,研究了苯酚和邻甲酚的致突变效应及对生殖细胞的DNA损伤作用。实验结果表明,苯酚和邻甲酚能诱发小鼠骨髓细胞微核率的增加,并在一定剂量范围内呈剂量效应关系。苯酚和邻甲酚对人淋巴细胞、小鼠睾丸生殖细胞及鲫鱼红细胞的DNA均有不同程度的损伤作用。3种彗星试验的结果均表明,阴性对照组仅有2.5%-7.5%的细胞出现DNA迁移,且迁移距离很小,损伤程度为2.5-8.0(专用单位),而阳性对照组表现出99.5%-100%的细胞拖尾率,并且细胞严重损伤,其损伤程度为248-361.8(专用单位),这证明了实验系统的可靠性。试验结果还表明,苯酚和邻甲酚对3种细胞DNA损伤作用随剂量的增加而增加,并呈现剂量效应关系。小鼠睾丸细胞及鲫鱼红细胞与人外周血淋巴细胞相比,NDA损伤程度更为严重,揭示上述两种细胞对苯酚和邻甲酚的损害作用更为敏感。  相似文献   

4.
对成年绵羊耳部皮肤细胞进行培养传代,将培养出的成纤维细胞经血清饥饿法处理后,作为核供体移植到MII期去核卵母细胞中进行核移植胚胎的生产,用细胞驰素B法与离子霉素+6-DMAP法对核移植胚胎(重构胚)在电融合后进行化学激活,然后在38.6度,5%CO2,最大相对湿度条件下,进行体外培养(IVC),重构胚卵裂率分别为37.8%与43.8%(51/135与81/185),囊/桑葚胚率分别为9.8%和12.3%(5/51和10/81),在融合电压1.5kV/cm,持续时间30us,脉冲次数为2次的条件下,孤雌激活胚胎的卵裂率和囊/桑葚胚率分别为81.0%和12.9%。  相似文献   

5.
在pH8.3的NH3-NH4Cl介质中,KSCN存在下铜(Ⅱ)与2-(5-溴-2-吡啶偶氮)-5-二乙氮基酚(5-Br-PADAP)生成络合物,在线性扫描示波极谱仪上于-0.35V(vs.SCE)出现一络合物吸附波。二阶导数峰高与铜(Ⅱ)浓度在7.81×10-9~8.00×10-6mol/L范围内里线性关系,检出限为3.13×10-9mol/L。用多种电化学方法研究了极谱波的性质及电极反应机理,峰电流由中心离子铜(Ⅱ)还原产生。试验了多种离子对峰电流的影响,方法已用于矿样中铜的测定,结果满意。  相似文献   

6.
甲醛对雄性小鼠生殖细胞毒作用的研究   总被引:6,自引:0,他引:6  
研究了液态和气态甲醛对雄性小鼠生殖细胞的毒作用,选用SPF级昆明种纯系雄性小鼠作为研究对象,液态甲醛染毒剂量分别为0.20,2.00,20.00mg/kg体重,采用腹腔注射染毒7d,观察睾丸组织的病理改变,并计算脏器系数、精子存活率、活动率、精子数及畸形率.气态甲醛染毒剂量分别为0.5,1.0,3.0mg/m^3,连续动态染毒72h,于首次染毒后第15天观察睾丸细胞的微核率,结果表明,液态甲醛能引起睾丸组织病理损伤,脏器系数、精子存活率、活动率和精子数减少,畸形率升高;气态,甲醛能诱导早期精细胞微核率增加,均呈现一定的剂量反应关系,液态甲醛和气体甲醛均具有小鼠生殖细胞毒性。  相似文献   

7.
水稻(辽盐9)种子在LS+2,4-D(2,4-二氯苯氧乙酸)2.0~3.0mg/L的培养基上进行诱导培养,经3~4次继代后,即可得到淡黄色颗粒性愈伤组织;将该种愈伤组织在LS+2,4-D2.0~3.0mg/L+LH(水解乳蛋白)300mg/L的液体培养基上进行振荡培养,经4~5次继代后,即可建立起良好的细胞悬浮系;培养基中附加2.0~2.5mg/LKT,使愈伤组织和悬浮细胞均可再生,其再生率分别为15.9%~17.9%和18.1%~20.8%。  相似文献   

8.
酵母菌多糖对肉鸡促长增重的作用   总被引:1,自引:0,他引:1  
酵母菌多糖(YPS)是一种具有生物活性的新型微生态调节剂。用适量的YPS对肉鸡进行肌注和饮服,均可使鸡增重,在喂给含喹乙醇添加剂的全价商品饲料中,1-2组(饮服YPS剂量为20mg/kg)和3-4组(肌注YPS剂量为2mg/只)肉鸡的增重效果显著,分别为4.00%和3.45%;在喂给不含喹乙醇添加剂的全价商品饲料中,2-2组(饮服YPS剂量为40mg/kg)和2-3组(肌注YPS剂量为2mg/只)肉鸡的增重效果显著,分别为6.30%6.03%。此外,2-2组的肉料比最低(1:2.08),饲料报酬比对照组提高6.72%。  相似文献   

9.
呋喃二烯的体内外抗肿瘤作用研究   总被引:2,自引:1,他引:1  
探讨了呋喃二烯的体内外抗肿瘤作用及作用机理.采用MTT法检测呋喃二烯对10种人肿瘤细胞的体外增殖抑制作用,研究发现呋喃二烯对体外培养的多种肿瘤细胞具有很强的抑制和杀伤效应,其IC50在0.98-4.81μg/mL.并对敏感的白血病细胞HL-60进行初步的作用机制研究,其形态学和流式细胞分析试验均表明它能有效诱导细胞调亡.整体动物试验结果可证实呋喃二烯乳注射液能明显延长荷腹水癌S180小鼠的生存期,生命延长率分别为80mg/kg(91.2%),30mg/kg(82.4%),10mg/kg(70.59%).  相似文献   

10.
以大麦为材料,研究了二氧化硫(SO2)体内衍生物NaHSO3-Na2SO3混合液(1:3,mmol/L)对大麦幼苗叶片叶绿素含量、叶片和根系过氧化物酶(POD)活性,及对根尖细胞姊妹染色单体交换(SCE)的影响.研究结果表明:一定浓度的NaHSO3-Na2SO3混合液对大麦叶片叶绿素含量、根尖细胞SCE频率、叶片和根系细胞POD活性有明显影响,且呈浓度和时间效应;对大麦根尖SCE及POD增值的诱导在时间上具有一致性.  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.
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   

14.
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   

15.
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   

16.
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   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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