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1.
蛇毒心脏素对荷瘤小鼠的抗肿瘤作用初步研究   总被引:6,自引:1,他引:5  
梁敏仪  陈家坤 《蛇志》1998,10(2):1-4
目的 探讨蛇毒心脏毒素(CTX)对荷瘤小鼠S180腹水瘤细胞生长抑制的影响。方法 小鼠腹腔接种S180活瘤细胞,连续10d分别腹腔注CTX0.8mkg、0.4mg/kg、0.2mg/kg,分别统计荷瘤小鼠的体重变化和癌细胞死亡率,并用有丝分裂完全民法分析体内癌细胞的有丝分裂过程,结果 CTX各剂量组荷瘤小鼠的体重抑制和癌细胞的有丝分裂,表现在0.4mg/kg实验组腹水S180细胞处于有丝分裂前期和  相似文献   

2.
眼镜蛇毒细胞毒素的抗肿瘤作用   总被引:1,自引:0,他引:1  
王锡锋  曹宜生 《蛇志》1999,11(3):16-20
目的 研究眼镜蛇毒细胞毒素( C V C T X)的体内抗肿瘤作用。方法 小鼠皮下、腹腔接种 S180 、 E A C后, 于接种部位注射不同剂量的 C V C T X, 每天 1 次, 连续10 天, 观察瘤重抑制率和生命延长率。结果 适当剂量(02~08m g/kg) 的 C V C T X 能明显抑制肿瘤的生长 ( P< 001),小鼠的存活时间明显延长( P < 001)。结论  C V C T X 在小鼠体内对 S180 、 E A C有明显地抗肿瘤作用。  相似文献   

3.
眼镜蛇毒心脏毒素对人肺癌A549细胞株的遗传毒性研究   总被引:6,自引:0,他引:6  
梁敏仪  陈家坤 《蛇志》1997,9(4):10-13
探讨蛇毒心脏毒素(CTX)对人肺癌A549细胞株的遗传毒性。方法应用眼镜蛇毒(CTX)处理体外培养的人肺癌A549细胞株,通过细胞生长速率、有丝分裂指数(MI)、细胞周期动力学指数(CKI)、银染核仁组织区计数(AgNOR)、姐妹染色单体交换(SCE)频率、二倍体细胞比率的分析,观察CTX所产生的遗传毒性作用。结果CTX能明显抑制肺癌A549细胞的DNA复制过程和rRNA的合成,且随着浓度增大,癌细胞受抑制程度越大。用2mg/LCTX作用肺癌细胞后,SCE频率比对照组明显下降(P<0.01),但对照组和实验组出现的二倍体细胞比率差异不明显(P>0.05)。结论眼镜蛇毒CTX可抑制肺癌细胞的生长恶性程度,但使其恶性表型逆转的作用不明显。  相似文献   

4.
艾氏腹水癌细胞和肉瘤S-180细胞是抗肿瘤药物筛选常用细胞株.实验采用取自小鼠腹腔的第7~8天的艾氏腹水癌和S-180细胞,用31P磁共振谱测得了细胞内小分子含磷代谢成分;计算了细胞内pH值;还用31P谱探讨了作用机制不同的三种抗代谢物:碘乙酸、2,4-二硝基苯酚及棉酚对艾氏腹水癌细胞代谢的影响  相似文献   

5.
蛇毒心脏毒素对动物细胞的遗传损伤和生殖毒性研究   总被引:1,自引:0,他引:1  
梁敏仪  管锦霞 《蛇志》1998,10(1):7-10
目的 应用眼镜蛇毒心脏毒素(CTX)作用于小鼠的骨髓细胞和生殖细胞,以探讨CTX对动物体的生殖毒性和遗传毒性。方法 对小鼠腹腔注射不同剂量CTX,通过生殖毒性实验和致突变实验,分析孕鼠的胚胎存活率,骨髓细胞和精母细胞的染色体畸变率。结果:CTX能影响胎鼠的生长发育,使孕鼠的增重和活胎率均明显地降低(P〈0.001),染色体畸变实验显示CTX0.4mg/kg剂量上精母细胞多倍体和非整倍体细胞数目增高  相似文献   

6.
本文从亮叶扬酮中分离提取出类生物活性物质,并进行小鼠体内抗肿瘤试验和小鼠S-180肿瘤细胞中p53基因表达抑制实验。研究结果表明,亮叶所桐中总黄酮含量达28.4%,黄酮提取物在剂量500mg·kg^-1时对小鼠肉瘤S-180的抑瘤率为64.0%,对艾氏腹水癌(EAC)Ⅰ小鼠的生命延长率为51.25%,有显著的抗肿瘤作用,并且药效与用药量有关。同时发现,黄酮类提取物的抗肿瘤活性优于化疗药物呋喃氟尿嘧  相似文献   

7.
甲型流感病毒PR8株两次注射治疗S180腹水瘤小鼠(6周龄),第一次注射后小鼠存活率为52%,间隔不同时间二次注射PR8,小鼠存活率均有不同程度提高,达60%—90%;小鼠植入S180细胞后第2、5、7、10天分别给予病毒治疗,其存活率分别是70%、35%、17.5%和0,对照组则100%死亡。为观察荷瘤鼠体内抗病毒抗体对疗效的影响,首先用PR8免疫小鼠,待产生抗体后植入S180细胞再行病毒治疗,小鼠存活率为62.5%;而未经病毒免疫过的荷瘤鼠,其存活率仅33.3%。PR8治疗“老”龄荷瘤鼠(10月龄),存活率为0,平均生存时间为22.3天,对照组为20.5天。环磷酰胺可增加病毒对瘤细胞的感染率,二者协同作用,能提高小鼠存活率。  相似文献   

8.
低分子量硫酸葡聚糖对小鼠造血干细胞动员作用的研究   总被引:3,自引:0,他引:3  
给小鼠静脉注射低分子量(<10 ̄4u)硫酸葡聚糖(DS)15mg/kg后外周血中白细胞、单个核细胞(mononuclearcek,MNC)、CFU-GM、BFU-E和CFU-Mix产率等指标出现时相性变化。给药后1h开始升高,2h达到高峰、分别为药前值的2.2、2.6、3.8、4.4和3.0倍,7h时趋向正常。给药后2h上述各类细胞在外周血中的含量随着DS的剂量增加而增加。白细胞、MNC计数在DS180mg/kg时达到峰值,均为对照组的4倍。240mg/k8时未见明显增加。不同剂量DS对各系祖细胞均有不同程度的动员作用,DS剂量15-30mg/kg效果最好,每升血中CFU-GM、BFU-E、CFU-Mix的数量分别相当于对照组的5.0、11.9和8.8倍。其峰值出现时间与白细胞、MNC不同,表明DS对不同类型细胞的作用机制也不尽一致。经口给小鼠投以DS240和48omg/kg后,未见外周血中白细胞、MNC计数有显著性升高,提示对造血干细胞没有动员作用。  相似文献   

9.
SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)检测中国眼镜蛇毒蛋白酶水解纤维蛋白原的作用方式,发现该蛋白酶可迅速水解纤维蛋白原Aα链,对γ链作用较弱,对Bβ链无作用,是一种新型的α-纤维蛋白原本科,用比浊法测定血小板聚集率,证实中国眼镜蛇毒蛋白酶低剂量()0.025)mg/kg)、中剂量(0.05mg/kg)以及高剂量(0.1mg/kg)体内给药浓度依赖性地抑制ADP(10μmol/L)和胶原(1  相似文献   

10.
雄性SD大鼠33只,体重180—250g,随机分成四组。正常对照组6只;哌唑嗪组8只,于实验第1、2、3日上午用哌唑嗪灌胃(1mg/kg体重)共3次,第2日下午腹腔注射半乳糖胺(600mg/kg体重)1次,第4日上午处死动物,取肝脏及血清作有关检查;普萘洛尔组及N.S对照组分别用普萘洛尔(2mg/kg体重)及N.S(10ml/kg体重)代替哌唑嗪灌胃,处理程序同哌唑嗪组。结果表明:一、哌唑嗪能显著减轻肝脏病变及血清ALT的升高。二、哌唑嗪对肝损害后肝组织SDH、Mg2+-AT-Pase、ChE、ACP、CCo等酶活性的恢复有显著效果。三、哌唑嗪组LPO明显低于N.S对照组(P<0.01)而SOD活性明显高于N.S对照组(P<0.01)。普萘洛尔组各项指标同对照组比较均无显著差异(P>0.05)。提示:哌唑嗪对大鼠实验性肝损害有一定的保护作用。  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

13.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

14.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

15.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

16.
17.
Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H2-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H2 with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD+, FMN+, and NAD(P)+ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H2OCO2+2H++2e- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation  相似文献   

18.
Since the introduction of the concepts of allostery about four decades ago, much advancement has been made in elucidating the structure-function correlation in allostery. However, there are still a number of issues that remain unresolved. In this review we used mammalian pyruvate kinase (PK) as a model system to understand the role of protein dynamics in modulating cooperativity. PK has a triosephosphate isomerase (TIM)(α/β)8 barrel structural motif. PK is an ideal system to address basic questions regarding regulatory mechanisms about this common (α/β)8 structural motif. The simplest model accounting for all of the solution thermodynamic and kinetic data on ligand-enzyme interactions involves two conformational states, inactive ET and active ER. These conformational states are represented by domain movements. Further studies provide the first evidence for a differential effect of ligand binding on the dynamics of the structural elements, not major secondary structural changes. These data are consistent with our model that allosteric regulation of PK is the consequence of perturbation of the distribution of an ensemble of states in which the inactive ET and active ER represent the two extreme end states. Sequence differences and ligands can modulate the distribution of states leading to alterations of functions. The future work includes: defining the network of functionally connected residues; elucidating the chemical principles governing the sequence differences which affect functions; and probing the nature of mutations on the stability of the secondary structural elements, which in turn modulate allostery.  相似文献   

19.
20.
(鱼句)亚科花(鱼骨)型鱼类骨骼系统的比较   总被引:2,自引:0,他引:2  
对我国花型Hemibarbuspattern鱼类作了骨骼系统比较,结果表明,此类型鱼类脑颅较长,副蝶骨平直或稍弯曲,眶蝶骨腹纵嵴发达(铜鱼Coreius septentrionalis例外),下颞窝和咽突中等大,基枕骨后突发达;脑颅中的上筛骨的后突、侧筛骨的外筛突,蝶耳骨的外突、上耳骨的后突、围眶骨和后颞窝等均有明显的差异;咽颅中的舌颌骨、尾舌骨、鳃盖骨和下咽齿的列数等又有显著的区别;附肢骨骼中的腰带骨、脊椎骨中的复合神经骨和第4椎骨腹侧的悬器等也有不同之处。据此,这些差异和区别可作为属间或种间的分类依据。  相似文献   

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