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991.
Role of follicle stimulating hormone and epidermal growth factor in the development of porcine preantral follicle in vitro 总被引:2,自引:0,他引:2
The aim of the present study was to assess the role of follicle stimulating hormone (FSH), epidermal growth factor (EGF) or a combination of EGF and FSH on the in vitro growth of porcine preantral follicles, estradiol secretion, antrum formation, oocyte maturation and subsequent embryonic development. Porcine preantral follicles were cultured for 3 days in the absence or in the presence of FSH or EGF. Oocytes from these follicles were then matured, fertilized in vitro and embryos were cultured. Estradiol secretion and histological analysis of cultured follicles were also carried out. The results showed that when FSH, or a combination of EGF and FSH, was added to the culture medium, most of preantral follicles grew to antral follicles with high estradiol secretion and the oocytes from these antral follicles could mature, fertilize and develop to the blastocyst stage. Without FSH, or a combination of EGF and FSH, preantral follicles were unable to develop to the antral stage. Histology demonstrated that the resulting follicles were nonantral, estradiol production was reduced and none of their oocytes matured after in vitro maturation. The results indicate the essential role of FSH in promoting in vitro growth of porcine preantral follicle, estradiol secretion, antrum formation, oocyte maturation and subsequent embryonic development. EGF with FSH treatment of porcine preantral follicles improves the quality of oocytes, shown by a higher frequency of embryonic development. 相似文献
992.
Inclusion of dithiothreitol (DTT) in the extraction buffer and pre-incubation of apple leaf ADP-glucose pyrophosphorylase (AGPase) with DTT resulted in a decrease in AGPase activity whether the assay was performed in the presence or absence of 3-phosphoglycerate (PGA). When PGA was included in the pre-incubation mixture or when pre-incubation of AGPase with PGA was followed by DTT, the latter did not cause any decrease in AGPase activity. However, once AGPase was decreased by DTT, subsequent incubation of the enzyme with PGA did not reverse the decrease. Pre-incubation of AGPase from leaves of Arabidopsis thaliana, sorghum, soybean, tobacco, spinach, wheat, barley, tomato and potato, and tubers of potato with DTT, generally caused a decrease in AGPase activity when assayed in the presence of PGA. When assayed in the absence of PGA, however, a diverse response of AGPase was observed among species to pre-incubation with DTT. The activity of AGPase from potato tubers was increased by DTT; the activity of AGPase from both potato and tomato leaves was not affected by DTT; the activity of AGPase from leaves of other species was decreased by DTT. It is concluded that DTT decreases in vitro activity of AGPase from leaves of apple and many other plant species such that DTT should not be routinely included in the extraction or assay mixture of leaf AGPase. 相似文献
993.
Deskus JA Epperson JR Sloan CP Cipollina JA Dextraze P Qian-Cutrone J Gao Q Ma B Beno BR Mattson GK Molski TF Krause RG Taber MT Lodge NJ Mattson RJ 《Bioorganic & medicinal chemistry letters》2007,17(11):3099-3104
A series of indole tetrahydropyridine and indole cyclohexenylamines was prepared, and their binding affinities at the human serotonin transporter (SERT) were determined. In particular, a nitrile substituent at the C5 position of the indole ring gave potent SERT activity. The stereochemistry of the N,N-dimethylamine substituent was determined for the most potent indole cyclohexenylamine, 6a. The enantiomers of 6a were energy minimized and compared to other conformationally restricted SSRIs. Compound 6a was found to give a dose-response similar to the SSRI fluoxetine in microdialysis studies in rats. 相似文献
994.
描述了点翅盲蝽属2新种,记述了点盲蝽属中国1新纪录种.以新名Bryocoris(Cobalorrhynchus)latiusculus代替Bryocoris(Cobalorrhynchus)latus Hu et Zheng,2004.模式标本保存在南开大学昆虫学研究所.叉突点翅盲蝽,新种Compsidolom furcillatum Li et Liu,sp.nov.正模(♂),云南玉龙山(27°10'N,100°18'E),1979-08-10,郑乐怡、邹环光采.副模11(♂)(♂),16♀♀,同正模.眼间距大于眼宽,触角第Ⅰ节基部距黑色环斑,中部具2大黑斑,触角第Ⅱ节两端黑色,跗节基部黑色,雄虫体背斑点不明显,阳茎端细长,端部"Y"型,次生生殖孔近端部.全北点翅盲蝽Compsidolon salicellum(Herrich-Schaeffer,1841)中国新纪录观察标本:4(♂)(♂),2♀♀,湖北神农架保护区(31°45'N,110°40'E),2004-08-12,李传仁采;2(♂)(♂),2♀♀,湖北五峰(30°12'N,116°40'E,alt.1 000 m),1999-07-11,郑乐怡采.分布:湖北(神农架、五峰);瑞典,丹麦,俄罗斯,德国,斯洛伐克,法国,加拿大,美国.钩点翅盲蝽,新种Compsidolon uncum Li et Liu,sp.nov.正模(♂),西藏亚东(27°31'N,88°58'E,alt.2 600-2 900 m),2003-08-27,薛怀君、王新谱采.副模:20(♂)(♂),12♀♀,同正模.体背除楔片外被密集的黑褐色斑点,额区具暗纹,近头顶后缘处横行排列1排黑色圆斑,触角第Ⅰ、Ⅱ节基部黑色,阳茎端刺突两枚,一枚向下弯曲,钩状,一枚直.宽蕨盲蝽,新名Bryocoris(Cobalorrhynchus)latiusculus Hu et Zheng,nom.nov.Bryocoris(Cobalorrhynchus)latus Hu et Zheng,2004.Acta Zootaxonomica Sinica,29(2):272-275.Bryocoris(Cobalorrhynchus)latus Hu et Zheng 2004为B.(C.)latus Lin 2003的次同名,现命以新名Bryocoris(Cobalorrhynchus)latiusculus Hu et Zheng,次同名同时废止. 相似文献
995.
甘肃省药用植物秦艽野生资源现状及开发利用 总被引:2,自引:0,他引:2
甘肃省是秦艽的原产地之一,蕴藏着丰富的野生资源.由于不合理的采挖利用,致使资源遭到破坏.对甘肃省秦艽野生资源的种类、分布及生态环境特征、生长情况、采挖与收购现状进行了阐述,并提出了合理开发利用的对策. 相似文献
996.
基因芯片技术检测3种肠道病原微生物方法的建立 总被引:2,自引:0,他引:2
目的:建立一种运用多重PCR和基因芯片技术检测和鉴定伤寒沙门氏菌、痢疾杆菌和单核细胞增生利斯特菌的方法。方法:分别选取伤寒沙门氏菌染色体ViaB区域中编码调控Vi抗原表达的基因(vipR)、痢疾杆菌编码侵袭质粒抗原H基因(ipaH)和单核细胞增生利斯特菌溶血素基因(hlyA)设计引物和探针,探针3'端进行氨基修饰,下游引物标记荧光素Cy3。在优化的PCR和杂交反应条件下,进行三重PCR扩增,产物与包括3种致病菌特异性探针的基因芯片杂交。在评价基因芯片的特异性和灵敏度之后,对临床样本进行检测。结果:只有3种目的致病菌的PCR产物在相应探针位置出现特异性信号,其他阴性细菌均无信号出现;3种致病菌的检测灵敏度均可达到103CFU/mL;检测30例临床样本的结果与常规细菌学培养结果一致。结论:所建立的可同时检测伤寒沙门氏菌、痢疾杆菌和单核细胞增生利斯特菌的基因芯片方法快速、准确,特异性高,重复性好,为3种肠道致病菌的快速检测和鉴定提供了新方法和新思路。 相似文献
997.
998.
对山罗花和天柱山罗花的4个居群的15项形态特征进行了数值分析。结果表明:形态性状在4个居群间均存在一定程度的变异,居群间变异系数的平均值从小到大排列为:天柱山居群(天柱山罗花)、天柱山居群(山罗花)、黄山居群(山罗花)、鹞落坪居群(山罗花);天柱山罗花与山罗花种间的形态差异已达到极显著水平,山罗花的3个居群间部分性状也具有极显著的形态差异;以形态特征为基础的Q-聚类分析可以把天柱山罗花和山罗花聚为两类,但山罗花(天柱山居群)和其他2个居群在较远处聚在一起,R-聚类分析发现了强正相关关系、弱正相关关系、弱负相关关系的性状。 相似文献
999.
Du L Chen J Qi Y Li D Yuan C Lin MC Yew DT Kung HF Yu JC Lai L 《International journal of nanomedicine》2007,2(4):805-812
We report the preparation of a non-polymer coated superparamagnetic nanoparticle that is stable and biocompatible both in vitro and in vivo. The non-polymer, betaine, is a natural methylating agent in mammalian liver with active surface property. Upon systemic administration, the nanoparticle has preferential biodistribution in mammalian liver and exhibits good reduction of relaxivity time and negative enhancement for the detection of hepatoma nodules in rats using MRI. Our data demonstrate that the non-polymer coated superparamagnetic nanoparticle should have potential applications in biomedicine. 相似文献
1000.
Kim YS Xiao HZ Du EQ Cai GS Lu SY Qi YP 《Journal of biochemistry and molecular biology》2007,40(4):571-576
Three anti-apoptosis genes, Ls-iap2, iap3 and p49 were found in Leucania separata multiple nuclear polyhedrovirus. Amino acid sequence homology of Ls-IAP2 and Ls-IAP3 with Op-IAP2 and Op-IAP3 from Orgyia pseddotsugata MNPV were 20% and 42%, while that of Ls-P49 is 28% with Sl-P49 from Spodoptera littorolis MNPV. Ls-IAP2 contains one baculoviral IAP repeat (BIR) domain followed by a RING domain, while Ls-IAP3 contains two BIRs and a RING. Ls-P49 contains a reactive site loop, predicted cleavage site (KKLD(74) downward arrow G) that is different from Sl-P49 (TVID(94) downward arrow G). Expressed Ls-iap3 or Ls-p49 under presence of actinomycin D in SF9 cells, DNA ladder assay revealed that Ls- IAP3 or Ls-P49 could block the apoptosis of SF9 cells induced by actinomycin D. Replication of p35 deficient-mutant Autographa californica MNPV in SF9 cells was also rescued when Ls-iap3 or Ls-p49 was expressed transiently. No anti-apoptotic activity was observed for Ls-IAP2. The results showed that both of Ls-IAP3 and Ls-P49 were functional apoptotic suppressors in SF9 cells. 相似文献