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991.
The present investigation provides an efficient diagnostic method based on polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) analysis to discriminate between two cryptic species of scabbardfish, Aphanopus carbo and A. intermedius, with commercial relevance in several European fish markets. Two DNA fragments from the mtDNA, including control region and partial cytochrome oxidase subunit I genes of about 1100 bp and 700 bp, respectively, were isolated by PCR amplification. Digestion of the amplicon including the control region with HaeII and the amplicon including the COI gene with Sau3AI restriction enzymes allowed an unequivocal discrimination between the two scabbardfish species. This PCR–RFLP method allowed a clear and rapid discrimination of the trichiurid species studied. 相似文献
992.
Ki-Yeol Kim Gui Youn Lee Jin Kim Hei-Cheul Jeung Hyun Cheol Chung Sun Young Rha 《Genomics》2009,94(5):317-323
Array comparative genomic hybridization (aCGH) provides a technique to survey the human genome for chromosomal aberrations in disease. The identification of genomic regions with aberrations may clarify the initiation and progression of cancer, improve diagnostic and prognostic accuracy, and guide therapy. The analysis of variance (ANOVA) model is widely used to detect differentially expressed genes after accounting for common sources of variation in microarray analysis. In this study, we propose a method, shifted ANOVA, to detect significantly altered regions. This method, based on the standard ANOVA, analyzes changes in copy number variation for regions. The selected regions have the group effect only, but no effect within samples and no interactive effects. The performance of the proposed method is evaluated from the homogeneity and classification accuracies of the selected regions. Shifted ANOVA may identify new candidate genes neighboring known because it detects significantly altered chromosomal regions, rather than independent probes. 相似文献
993.
Angeline S. Andrew Jiang Gui Arthur C. Sanderson Rebecca A. Mason Elaine V. Morlock Alan R. Schned Karl T. Kelsey Carmen J. Marsit Jason H. Moore Margaret R. Karagas 《Human genetics》2009,125(5-6):527-539
Bladder cancer is the fourth most common malignancy in men and the eighth most common in women in western countries. Single nucleotide polymorphisms (SNPs) in genes that regulate telomere maintenance, mitosis, inflammation, and apoptosis have not been assessed extensively for this disease. Using a population-based study with 832 bladder cancer cases and 1,191 controls, we assessed genetic variation in relation to cancer susceptibility or survival. Findings included an increased risk associated with variants in the methyl-metabolism gene, MTHFD2 (OR 1.7 95% CI 1.3–2.3), the telomerase TEP1 (OR 1.8 95% CI 1.2–2.6) and decreased risk associated with the inflammatory response gene variant IL8RB (OR 0.6 95% CI 0.5–0.9) compared to wild-type. Shorter survival was associated with apoptotic gene variants, including CASP9 (HR 1.8 95% CI 1.1–3.0). Variants in the detoxification gene EPHX1 experienced longer survival (HR 0.4 (95% CI 0.2–0.8). These genes can now be assessed in multiple study populations to identify and validate SNPs appropriate for clinical use. 相似文献
994.
Isolation of Y- and X-linked SCAR markers in yellow catfish and application in the production of all-male populations 总被引:3,自引:0,他引:3
Sex controls have been performed in some farmed fish species because of significant growth differences between females and males. In yellow catfish ( Pelteobagrus fulvidraco ), adult males are three times larger than female adults. In this study, six Y- and X-linked amplified fragment length polymorphism fragments were screened by sex-genotype pool bulked segregant analysis and individual screening. Interestingly, sequence analysis identified two pairs of allelic genes, Pf33 and Pf62 . Furthermore, the cloned flanking sequences revealed several Y- and X-specific polymorphisms, and four Y-linked or X-linked sequence characterized amplified region (SCAR) primer pairs were designed and converted into Y- and X-linked SCAR markers. Consequently, these markers were successfully used to identify genetic sex and YY super-males, and applied to all-male population production. Thus, we developed a novel and simple technique to help commercial production of YY super-males and all-male populations in the yellow catfish. 相似文献
995.
干细胞移植患者口腔粘膜上皮细胞基因型观察 总被引:1,自引:0,他引:1
目的观察异基因外周血干细胞移植患者口腔上皮细胞基因型的变化,判断干细胞生长情况。方法采用PCR-STR分型技术对31例外周血干细胞移植患者血液、口腔拭子及部分患者毛根进行基因分型。结果31例患者移植后血液均为供体基因型;25例患者口腔上皮细胞基因型为受体与供体嵌合体型,4例为受体原有基因型,2例转为供体基因型;11例检测了毛根基因型,均为受体的原有基因型。结论移植后外周血干细胞可以转变为口腔粘膜上皮细胞,这种转变有望成为判断患者干细胞生长情况及移植后治疗效果的一项新指标。这对干细胞治疗各种血液恶性疾病及法医学应用具有较高的参考价值。 相似文献
996.
人OC-3-VGH卵巢癌细胞裸小鼠肿瘤模型的建立 总被引:1,自引:0,他引:1
目的建立人OC-3-VGH细胞株卵巢癌裸小鼠模型并观察该肿瘤生物学生长特性。方法OC-3-VGH细胞株复苏后加入10 mL RPMI-1640培养液,放入培养箱,传2~3代后,取细胞悬液,均以4×106个细胞,每只0.2 mL分别接种至BALB/c雌性裸小鼠皮下,2月后处死取材,观察肿瘤生长特性和转移情况。结果皮下接种一周后,裸鼠长出肿瘤,并随时间而增大,体积呈指数增长,第42天始,明显增大(P〈0.05)。组织学检查发现裸鼠皮下肿瘤细胞均细胞体积较大,细胞核大而染色深,核分裂相较多、异型性明显,接种2个月时,未发生其他组织转移。结论建立了新的卵巢癌动物模型,并初步研究了其生物学特性,为卵巢癌治疗方法的研究拓宽了道路。 相似文献
997.
998.
Secretion of citrate from roots in response to aluminum and low phosphorus stresses in Stylosanthes 总被引:2,自引:0,他引:2
Xiao Feng Li Fang Hua Zuo Gui Zhi Ling Yao Yan Li Yong Xiong Yu Pei Quan Yang Xing Lian Tang 《Plant and Soil》2009,325(1-2):219-229
Excess aluminum (Al) ions and phosphorus (P) deficiency are the key factors that limit plant growth in acid soils. Secretion of organic acids (OA) from roots has been proposed as an Al-resistance mechanism. Nonetheless, the correlation between Al resistance and this mechanism has not been tested beyond a very small number of Al-resistant and Al-sensitive genotypes. To elucidate the mechanisms responsible for plant adaptability to acid soils, we studied the secretion of OA from roots of Stylosanthes in response to high-Al and low-P stresses using six different genotypes. Relative root inhibition by 50?µM Al ranged from 25–71% and differed significantly among six Stylosanthes genotypes. Al treatment induced the secretion of citrate from the roots of Stylosanthes seedling in a dose- and time-dependent manner. Moreover, the secretion rate was significantly higher in the Al-resistant genotype. On the other hand, inhibition of Al-induced citrate secretion by phenylisothiocyanate or 9-anthracenecarboxylic acid resulted in an increase in Al content in Stylosanthes root apices. P deficiency also induced citrate secretion from Stylosanthes seedling roots. Furthermore, citrate secretion was much more robust with exposure to both excess-Al and P-deficiency stresses than under either stress alone. Unlike Al-induced citrate secretion, which was rapid, low-P-induced secretion was a slow process, with significant increases in secretion only becoming evident after 6 d of treatment with free phosphate. The lag between treatment with Al and citrate secretion was approximately 4 h. These results suggest that the secretion of citrate is a mechanism for resistance to both excess-Al and low-P stresses in Stylosanthes. 相似文献
999.
1000.
甘薯愈伤组织对干旱胁迫和盐胁迫的生理反应对比 总被引:15,自引:3,他引:12
研究干旱胁迫和盐胁迫对“芦选一号”。日‘薯愈伤组织可溶性蛋白、可溶性糖、脯氨酸含量、SOD活性等的影响,从而在细胞水平上探讨甘薯抵御渗透胁迫的生理机制。并分析甘薯细胞对干旱处理(PEG-6000)和盐处理(NaCl)的反应差异。结果表明,可溶性蛋白质含量在干旱胁迫下缓慢升高,在轻度和中度盐胁迫的生长前期和中期有较大幅度的上升。但后期下降,表明短时间盐胁迫下,Na^+可能促进可溶性蛋白的合成;MDA在重度干旱胁迫下的含量显著低于重度盐胁迫,而SOD活性显著高于盐胁迫。表明在盐胁迫下细胞膜透性增加的主要原网是膜脂过氧化作用。干旱处理则是PEG-6000脱水的直接结果;重度干旱胁迫下,可溶性糖含量在短期内迅速升高,然后下降,而脯氨酸含量则在胁迫中后期迅速上升。脯氨酸可能有补偿可溶性糖含量降低的作用。 相似文献