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71.
中国畲族群体D17S30位点遗传多态性研究 总被引:5,自引:0,他引:5
郭俊明 钟为群 赖日勇 叶金花 黄功华 毕新生GUO Jun-Ming ZHONG Wei-Qun LAI Ri-Yong YE Jin-Hua HANG Gong-Hua BI Xin-Sheng 《遗传》1997,19(4):29-32
采用聚合酶链反应 (PCR)技术对中国畲族群体270名无关个体D17S30位点的VNTR进行了研究,共检出12个等位基因,片段大小为168bp-1008bp,基因频率为0.0056-0.3259,杂合度为79.10%,父权排除率为0.4358。家系分析表明,扩增片段按孟德尔方式遗传。统计学分析证明,本资料符合Hardy-W einberg平衡定律(x2=79.97,v=66,P=0.1158>0.05)。
Abstract:The variable number of tandem repeat(VNTR)of D17S30 locus in 270 unrelated individuals of She ethnic group was studied by polymerase chain reaction(PCR).The results showed that 12 alleles were detected and their sizes ranged from 168bp to 1 008bp.The allele frequencies were 0.0056~0.3259,the heterozygosity of this locus was 79.10% and the paternity exclusion probability was 0.4358.The number of D17S30 VNTR allele and allele frequency of She were different from those of Han ethnic group in Mendelian Law.Statistical analysis demonstrated that their geneotypes were consistent with Hardy-Weinberg equilibrium(x2=79.97,v=66,P=0.1158>0.05). 相似文献
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Pine wilt disease (PWD) is a devastating disease to pine trees, which was caused by the pine wood nematode (PWN), Bursaphelenchus xylophilus, and causes major losses in coniferous forests in many countries and regions in the world. In order to screen actinomycete strains with high nematicidal activity against PWN, marine actinomycetes were isolated from the marine environment and their nematicidal activity were tested.The marine actinomycetes were isolated from the samples collected from the subtidal zones near Qingdao coast using the dilution and streak plate method and their culture supernatant were assayed in vitro for nematicidal activity against PWN using immersion test. The strain with high nematicidal activity was identified on the basis of morphology, cultural characteristics and 16S rDNA sequence analysis, and its optimal culture conditions for the production of nematicidal substances were investigated through the single-factor experiments.A total of 28 marine actinomycete strains were isolated from the samples. One of these strains, designated as strain HT-8 and isolated from sea sand, exhibited stronger nematicidal activity with a 88.30% corrected mortality of PWN treated with the culture supernatant for 30 h. The strain HT-8 was identified as Streptomyces termitum on the basis of morphology, cultural characteristics, 16S rDNA sequence and phylogenetic analysis. The results of the single factor experiment demonstrated that the optimal cultivation conditions of HT-8 for the production of nematicidal substances were inoculum age was 48 h, inoculum concentration was 6%, concentration of seawater was 100%, initial pH was 7.5 and incubating at 25 ℃ for 7 days.This study provides a theoretical basis for the development of marine microorganism resources and the utilization of natural nematicidal substances. 相似文献
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MAI Tiejun* WANG Xin* ZHANG Zhiwen XIN Dianqi NA Yanqun & GUO Yinglu . Institute of Urology First Hospital of Peking University Beijing China . Department of General Surgery First Hospital of Peking University Beijing China . Department of Physiology Peking University Beijing China 《中国科学:生命科学英文版》2004,(5)
76.
为了检测雷公藤制剂对长爪沙鼠繁殖功能的影响,根据预实验结果,将40只雄性长爪沙鼠分为40 mg/kg连续用药4周组(n=16)、100 mg/kg一次给药组(n=10)和1%CMC灌胃对照组(n=14)处理,6周后剖检,比较睾丸、附睾的脏器系数、精子密度、精子活力、精子形态和繁殖率等指标.结果表明40 mg/kg连续用药组鼠的睾丸、附睾脏器系数与对照组比较差异显著;精子密度、精子活力和活精子百分率显著下降;精子畸形率显著上升;繁殖率显著下降(df=1,P<0.05).100 mg/kg一次给药组除附睾脏器系数显著下降、精子畸形率显著上升外,其它指标与对照组无明显差异.该药对长爪沙鼠连续作用4周后不育效果明显,并且具有致畸性,在药物有效范围内,高浓度一次性给药方式不如较低浓度连续多次给药效果显著. 相似文献
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Suppression of angiotensin Ⅱ stimulated responses in aortic vascular smooth muscle cells of experimental cirrhotic rats 总被引:1,自引:0,他引:1
ZHANG RU GUO LIANG WANG PI LI ZHANG YING XIONG WEN BO ZHANG XING PENG WANG DE LING YIN QING JING 《Cell research》1999,(2)
INTRODUCTIONLivercirrhosisisoftencomplicatedbyhyperdynamiccirculation,whichischaracterizedbyadecreaseinarterialbloodpressureandperipheralvascularresistanceandanincreaseincardiacoutputandsplanchnicbloodnow[1].Thesehaemodynamicdisturbancesareproposedtocontributetothedevelopmelltofportalhypertension,retentionofsodiumandwater,ascitesformationandcorrelatewithprognosisoflivercirrhosis[2].Ithasbeensuggestedthatprimaryarterialvasodilationmayinducethishyperdynamiccirculation[3].Buttheunderlyingmec… 相似文献
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外源基因导入黄瓜获得突变新品系 总被引:9,自引:0,他引:9
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Mao-Zhi REN Quan-Jia CHEN Li LI Rui ZHANG San-Dui GUO 《植物学报(英文版)》2005,47(10):1254-1259
For the first time, a nodulin-like gene promoter was isolated from Gossypium hirsutum L. Guo Y18 by means of inverse PCR. Three plant expression vectors were constructed for functional identification of the promoter. These vectors were different only in promoter regions; three truncations of the nodulinlike promoter took the place of the CaMV35S promoter in the pBI121 plant expression vector. Then, the three vectors were introduced into cotton plants via the pollen tube pathway. The expression patterns of the gus gene driven by nodulin-like promoter truncations were investigated in the offspring of transgenic cotton plants. Histochemical GUS staining and fluorescence quantitative analysis were performed to achieve this goal. The results showed that the nodulin-like promoter was a strong, highly reproductive organspecific promoter, which demonstrated a much higher driver activity than the CaMV35S promoter did in cotton reproductive organs, but relatively lower activity in vegetation. Identification of the speciality and strength-determining regions of the nodulin-like promoter was also undertaken. 相似文献
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间歇性低压低氧与连续性低压低氧对大鼠血液动力学作用的比较(英文) 总被引:2,自引:0,他引:2
本研究旨在探讨并比较慢性间歇性低压低氧(intermitten thypobaric hypoxia,IHH)和慢性连续性低压低氧(continuous hypobaric hypoxia,CHH)对大鼠血液动力学作用的影响。40只成年Sprague—Dawley大鼠随机分为5组:对照组(CON),28天IHH处理组(IHH28),42天IHH处理组(IHH42),28天CHH组(CHH28)和42天CHH组(CHH42)。IHH火鼠于低压氧舱分别接受28或42天模拟5000m海拔高度低氧(11.1%O2)处理、每天6h。CHH处理大鼠生活在低压氧舱环境中,除每天半小时常氧供食、供水和清洁外,其余时间均分别接受时程为28或42天的模拟5000m海拔高度低氧(11.1%O2)处理。每周定时测定大鼠体重。通过导管法测定基础常氧和急性低氧状态下的血液动力学,包括半均动脉压(meanartery blood pressure,MAP)、心率(heartrate,HR)、左审收缩峰压(1eft ventricular systolic pressure,LVSP)、正负左率最人压力变化速率(maximum change rate of left ventricular pressure,±LVdP/dtmax)。通过生物化学方法测定大鼠心肌超氧化物岐化酶活性和丙二醛含量。并分别测定全心、左心室和右心室重量。结果显示:(1)CHH42大鼠基础HR和MAP低于CON,IHH和CHH28大鼠(P〈0.05)。(2)IHH大鼠表现出明显的抗心肌缺氧/复氧损伤作用,表现为急性低氧状态下的HR、MAP、LVSP和+LVdP/dtmax,改变明显低于CON大鼠(P〈0.05);CHH大鼠表现出更为明显的抗急性低氧心脏保护作用,表现为急性低氧的HR、MAP、LVSP和±LVdP/dtmax;改变明显低于CON和IHH火鼠(P〈0.05),但出现复氧损伤作用,表现为复氧过程中血液动力学的恢复明显低于CON和IHH大鼠(P〈0.05)。(3)与CON大鼠相比较,IHH和CHH大鼠心肌抗氧化能力明显增强(P〈0.05,P〈0.01)。(4)与IHH和CON大鼠相比较,CHH大鼠表现明显的右心室肥厚(P〈0.01)。结果表明,IHH可诱导有效的心脏保护作用,而无明显的不良反应,因而具有潜在的实际应用价值。 相似文献