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141.
Objective: We needed to establish an embryonic fibroblast cell line from the Langshan chicken (LSCEF61) to preserve their important genetic resources at the cellular level. Material and methods: The cell line was established from 9‐day‐old embryos by direct explant culture and cryopreservation techniques. Cell morphology, dynamic proliferation and any contamination present were tested, and the karyotype and levels of isoenzymes of lactic dehydrogenase and malic dehydrogenase were analysed. Four types of fluorescent protein exogenous genes for pEGFP‐C1, pEGFP‐N3, pEYFP‐N1 and pDsRed1‐N1 were transfected into the cells. Results: Showed that the cells were healthy and were of spindle shaped structure, without change in morphology. Cell growth curves were of typical S‐shape. Assays for microbial contamination were negative. The LSCEF61 line showed no cross‐contamination when assessed by isoenzyme analysis. Chromosome number (2n) = 78 on more than 90% of occasions. The four types of fluorescent protein extro‐genes appeared to be expressed effectively with high transfection efficiency between 15.6% and 38.6%. Conclusion: The cell line met each of the quality control standards required for the American Type Culture Collection. It had not only preserved the genetic resources of the important Langshan chicken at the cellular level, but also provided valuable material for genomic, post‐genomic and somatic cell cloning research and other applications. 相似文献
142.
Vinod R. Hegde Scott Borges Haiyan Pu Mahesh Patel Vincent P. Gullo Bonnie Wu Paul Kirschmeier Michael J. Williams Vincent Madison Thierry Fischmann Tze-Ming Chan 《Bioorganic & medicinal chemistry letters》2010,20(4):1384-1387
Several analogs of aristolochic acids were isolated and derivatized into their lactam derivatives to study their inhibition in CDK2 assay. The study helped to derive some conclusions about the structure–activity relation around the phenanthrin moiety. Semi-synthetic aristolactam 21 showed good activity with inhibition IC50 of 35 nM in CDK2 assay. The activity of this compound was comparable to some of the most potent synthetic compounds reported in the literature. 相似文献
143.
从拓扑结构的角度分析生化反应网络是生物信息学研究中的一个热点问题。通过将两种传统的途径分析方法(基元模式和极端途径)与Petri网的T不变量分析进行了比较,结果表明:它们本质上是一致的,但是采用Petri网的T不变量分析更便捷。然后,利用Petri网技术构建了PHB代谢模型。对该模型作了结构分析,将计算得到的23个T不变量进行了分组:I组表示简单的可逆反应,II组表示循环的反应,III组可用于调控ATP/ADP比率,IV组是与PHB生产直接相关的反应,可用于代谢工程以提高PHB的产率。最后讨论了Petri网的T不变量分析在这个领域中的应用。 相似文献
144.
利用RACE技术,首次从丽蝇蛹集金小蜂Nasonia vitripennis中克隆获得一个气味结合蛋白全长cDNA序列.该基因全长553 bp,开放阅读框411 bp,3'和5'端非编码序列分别为13 bp和129 bp.其推导的氨基酸序列编码136个氨基酸,推测编码蛋白质的分子量为15.4 kDa,等电点为8.76.同源性比对分析发现,丽蝇蛹集金小蜂气味结合蛋白基因与现已报道的其它昆虫气味结合蛋白基因在氨基酸水平上的相似性均低于30%,拥有6个保守半胱氨酸位点等气味结合蛋白所具有的典型特征.系统进化树分析表明,丽蝇蛹集金小蜂气味结合蛋白与意大利蜜蜂Apis mellifera气味结合蛋白2,3,4,5,6,7,8和12聚为同一族,与意大利蜜蜂气味结合蛋白5,6和8的进化程度最近.RT-PCR分析表明,丽蝇蛹集金小蜂气味结合蛋白基因不仅在雌、雄成虫触角中高度表达,而且在头部和足中有微弱表达. 相似文献
145.
Chun-Nan Lin A-Mei Huang Kai-Wei Lin Tzyh-Chyuan Hour Horng-Huey Ko Shyh-Chyun Yang Yeong-Shiau Pu 《Phytochemistry》2010,71(17-18):2140-2146
The diterpenoids (+)-ferruginol (1), ent-kaur-16-en-15-one (2), ent-8(14),15-sandaracopimaradiene-2α,18-diol (3), 8(14),15-sandaracopimaradiene-2α,18,19-triol (4), and (+)-sugiol (5) and the triterpenoids 3β-methoxycycloartan-24(241)-ene (6), 3β,23β-dimethoxycycloartan-24(241)-ene (7), 3β,23β-dimethoxy-5α-lanosta-24(241)-ene (8), and 23(S)-23-methoxy-24-methylenelanosta-8-en-3-one (9), isolated from Amentotaxus formosana, showed inhibitory effects on xanthine oxidase (XO). Of the compounds tested, compound 5 was a potent inhibitor of XO activity, with an IC50 value of 6.8 ± 0.4 μM, while displaying weak ABTS radical cation scavenging activity. Treatment of the bladder cancer cell line, NTUB1, with 3–10 μM of compound 5 and 10 μM cisplatin, and immortalized normal human urothelial cell line, SV-HUC1, with 0.3–1 μM and 10–50 μM of compound 5 and 10 μM cisplatin, respectively, resulted in increased viability of cells compared with cytotoxicity induced by cisplatin. Treatment of NTUB1 with 20 μM cisplatin and 10 or 30 μM of compound 5 resulted in decreased ROS production compared with ROS production induced by cisplatin. These results indicate that 10 or 30 μM of compound 5 in NTUB1 cells may mediate through the suppression of XO activity and reduction of reactive oxygen species (ROS) induced by compound 5 cotreated with 20 μM cisplatin and protection of subsequent cell death. 相似文献
146.
147.
Luis Gracia Elena Ibarz Sergio Puértolas José Cegoñino Fernando López-Prats Juan J Panisello Antonio Herrera 《Biomedical engineering online》2010,9(1):22
Background
A hip replacement with a cemented or cementless femoral stem produces an effect on the bone called adaptive remodelling, attributable to mechanical and biological factors. All of the cementless prostheses designs try to achieve an optimal load transfer in order to avoid stress-shielding, which produces an osteopenia. 相似文献148.
Sergio Puértolas José M Pérez-García Luis Gracia José Cegoñino Elena Ibarz José A Puértolas Antonio Herrera 《Biomedical engineering online》2010,9(1):49
Background
The proximal interphalange joint (PIP) is fundamental for the functional nature of the hand. The contracture in flexion of the PIP, secondary to traumatisms or illnesses leads to an important functional loss. The use of correcting splints is the common procedure for treating this problem. Its functioning is based on the application of a small load and a prolonged stress which can be dynamic, static progressive or static serial. 相似文献149.
Melek Güler-Yüksel Naomi B Klarenbeek Yvonne PM Goekoop-Ruiterman Jeska K de Vries-Bouwstra Sjoerd M van der Kooij Andreas H Gerards H Karel Ronday Tom WJ Huizinga Ben AC Dijkmans Cornelia F Allaart Willem F Lems 《Arthritis research & therapy》2010,12(3):R96
Introduction
To investigate whether accelerated hand bone mineral density (BMD) loss is associated with progressive joint damage in hands and feet in the first year of rheumatoid arthritis (RA) and whether it is an independent predictor of subsequent progressive total joint damage after 4 years.Methods
In 256 recent-onset RA patients, baseline and 1-year hand BMD was measured in metacarpals 2-4 by digital X-ray radiogrammetry. Joint damage in hands and feet were scored in random order according to the Sharp-van der Heijde method at baseline and yearly up to 4 years.Results
68% of the patients had accelerated hand BMD loss (>-0.003 g/cm2) in the first year of RA. Hand BMD loss was associated with progressive joint damage after 1 year both in hands and feet with odds ratios (OR) (95% confidence intervals [CI]) of 5.3 (1.3-20.9) and 3.1 (1.0-9.7). In univariate analysis, hand BMD loss in the first year was a predictor of subsequent progressive total joint damage after 4 years with an OR (95% CI) of 3.1 (1.3-7.6). Multivariate analysis showed that only progressive joint damage in the first year and anti-citrullinated protein antibody positivity were independent predictors of long-term progressive joint damage.Conclusions
In the first year of RA, accelerated hand BMD loss is associated with progressive joint damage in both hands and feet. Hand BMD loss in the first year of recent-onset RA predicts subsequent progressive total joint damage, however not independent of progressive joint damage in the first year. 相似文献150.
对α-氯丙酸脱卤酶发酵动力学进行了研究。基于Logistic方程和Luedeking-Piret方程,得到了描述Pseudomonas W20菌发酵过程菌体生长、α-氯丙酸脱卤酶生成及基质消耗的动力学数学模型和模型参数,对试验数据与模型进行了验证比较,模型计算值与试验结果拟合良好,平均相对误差大部分小于10%;对脱卤酶反应动力学进行了研究,结果表明脱卤酶的脱卤反应基本符合米氏方程,并求得最大反应速率V_(max)=1.11×10~(-5)mol/(g·min),表观米氏常数K_m=3.72×10~(-3)mol/L。 相似文献