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1.
以E.coli和耐辐射生球菌(Deinococcusradiodurans)为试材,研究了N^+离子注入对其SOD,CAT和POD活性的影响及共对自由基的清除,结果表明:D.radiodurans经N^+离子注入后SOD和CAT酶活高于E.coli的,而POD酶活不仅很低于E.coli的;随剂量的增大,两者SOD和CAT酶活均为增后减,只是其SOD酶活的变化峰值对应剂量分别为6×10^15N^+/  相似文献   

2.
鸡GnRH对体外培养的鸡卵泡膜细胞合成甾类激素的作用   总被引:1,自引:0,他引:1  
在建立鸡卵泡膜细胞体外无血清贴壁培养模型基础上,研究了鸡促性腺激素释放激素(cGnRHⅡ)对鸡卵胞膜细胞合成睾酮(T)和雌二醇(E2)的直接作用;以及在绵羊促黄体激素(oLH)或促卵泡激素(oFSH)存在时,cGnHⅡ对膜细胞合成T或E2的影响。实验结果如下:①在培养液中单独加入cGnRHⅡ,能促进F5、F3卵泡膜细胞合成T及E2,并具有剂量依赖关系;而对于F1卵泡膜细胞的作用效果不明显。②cGnRHⅡ与oLH(50ng)共同处理,当cGnRHⅡ低剂量(100g)时,膜细胞T合成量明显增加,而加大剂量时,T合成量则显著降低。③cGnRHⅡ(500ng)与oFSH(50ng)共同处理对膜细胞E2的合成有抑制作用,降低cGnRHⅡ的含量,可逐渐恢复oFSH对膜细胞E2合成的刺激作用。  相似文献   

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盐分和水分胁迫盐地碱蓬幼苗渗透调节效应的研究   总被引:15,自引:0,他引:15  
利用不同浓度NaCl和等渗PEG处理4d龄的盐地碱蓬(Suacda salsa(L.)Pall.)幼苗,10d后测定植株中主要有机溶质和无机离子的含量及叶片涌透势和涌透调节能力。结果表明,NaCl处理的无机离子总含量急剧增加,其中Na^2+、Cl^-半加最多,占总计算渗透势(COP)的71% ̄88%,总无机离子占COP的95% ̄97%。而有机溶质总含量则稍有降低,约上COP的2% ̄5%。PEG处理  相似文献   

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2min脉冲式10nmol鲑GnRH高效类似物sGnRH-A(Arg^6Trp^7Leu^8Pro^9NEt-LHRH)刺激导致离体灌流培育的鲤脑垂体迅速产生显著的GtH分泌峰,GtH分泌在刺激后30min内恢复到基础水平。4h10nmol/L sGnRH-A持续性刺激导致灌流培育的鲤脑垂体GtH分泌出现脱敏反应,整个过程包括刺激后迅速的GtH分泌峰相和随后持续低水平的GtH分泌相。无Ca^++的  相似文献   

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用PAGEA活性染色分析了D.radiodurans过氧化氢酶(Cat)和起氧化物歧化酶(SOD)。2种同种异型D.radiodurans(R1和Sark)的Cat在电泳带型上存在差异,两者Kat均可分为A、B和C3条带,但各带所占比例明显不同,SOD的分析结果表明,D.radiodurans SOD以Fe^2+和Mn^2+离子的嵌合体形式存在,其中Fe-SOD成分占90%以上。PAGE活性染色法  相似文献   

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X. C. ZHANG 《植物研究》1998,18(1):107-117
GENUSANTROPHYUMKAULF.FROMCHINAANDNEIGHBORINGREGIONSX.C.ZHANG(Theherbarium(PE),InstituteofBotany,ChineseAcademyofSciences,Bei...  相似文献   

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贵州冷蕨属一新种   总被引:2,自引:0,他引:2  
贵州冷蕨属一新种王筱英王培善(贵州科学院,贵阳550001)ANEWSPECIESOFCYSTOPTERIS(ATHYRIACEAE)FROMGUIZHOUWangXiaoying,WangPeishan(GuizhouAcademyofScienc...  相似文献   

8.
干旱胁迫对红松幼苗保护酶活性及脂质过氧化作用的影响   总被引:65,自引:3,他引:62  
阎秀峰  李晶  祖元刚 《生态学报》1999,19(6):850-854
随着土壤的逐渐干旱,红松(Pinus koraiensis Sieb.et.Zucc)幼苗叶中膜质过氧化产物丙二醛(MDA)含量和膜相对透性均在干旱处理后第3天迅速上升;组织自动氧化速率先是增加,在干旱处理第3天后恢复到处理前水平。保护酶SOD、POD、CAT的活性明显提高,只有ASP的活性下降。用PEG模拟干旱胁迫与土壤自然干旱胁迫结果略有不同,-1.0MPa PEG溶液对红松幼苗具有较为明显的  相似文献   

9.
NNK诱发BEP2D细胞产生活性氧及其对DNA的损伤   总被引:4,自引:0,他引:4  
通过测定细胞内和细胞上清中活性氧(reactive oxygen species,ROS)水平,以及DNA 加合物——8-羟基脱氧鸟嘌呤核苷(8-hydroxydeoxyguanosine,OH8dG)含量,对烟草特异亚硝胺类化合物4-甲基亚硝胺-1(3-吡啶基)-1-丁酮(4-(m ethylnitrosam ino)-1-(3-pyridyl)-1-butanone,NNK)诱发人乳头状病毒永生化的人支气管上皮细胞(hum an papillom avirus-im m ortalized hum anbronchialepithelialcellline,BEP2D)产生的ROS及其对DNA 的氧化损伤进行研究,并观察纳米硒的保护作用.结果表明,BEP2D 细胞经不同浓度的NNK 作用后,细胞内和细胞上清中ROS以及OH8dG含量均显著增加,并有较好的剂量效应关系.1 μm ol·L- 1纳米硒(nanoselenuim ,NS)能明显抑制NNK 诱发BEP2D细胞产生的ROS及OH8dG 水平.揭示NNK 能造成细胞的氧化损伤,而NS对NNK 所致细胞的氧化损伤有保护作用.  相似文献   

10.
高成芝   《广西植物》1994,14(1):20-22
广西獐牙菜属一新种高成芝(广西中医药研究所,南宁530022)ANEWSPECIESOFSWERTIAFROMGUANGXI¥GaoChengzhi(GuangxiInstituteofTraditionalMedical&Pharmaceutica...  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

18.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

19.
Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

20.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

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