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231.
The construction of linkage map is both a funda-mental research area and an important aspect of gene analyses in genetics. It provides the guidelines for breeding. A sound linkage map is also necessary for further genetic analysis. In recent years, great and rapid progress has been made in molecular biology, which enables fingerprinting of organisms at the ge-nomic level. Many molecular marker techniques have been well established. Heartening progress has been made in many organisms in the co…  相似文献   
232.
The endogenous retrovirus (ERV) is one kind ofretroviruses that integrated in the genome in the formof provirus and replicates with the proliferation of hostcells. The ERV may play a significant role in the evo-lution, pathology and physiology of animals[1]. Now,proviral sequences of ERV have been found in the ge-nome of many vertebrates, and the release of virionshas also been detected both in vivo and in vitro. Porcine endogenous retrovirus (PERV) embeddedin the genome of pigs belo…  相似文献   
233.
应用100条RAPD引物对三江白猪及其杂交亲本长白猪和东北民猪,以及大约克夏、圣特西和法系大白猪进行亲缘关系的DNA多态分析。其中15条引物的扩增结果具有明显的多态,将其扩增结果进行聚类分析,发现三江白猪与长白猪(遗传距离d = 0.090)、与东北民猪(d = 0.175)的亲缘关系较近,与大约克夏(d = 0.263)、法系大白(d = 0.223)、圣特西猪(d = 0.580)的亲缘关系较远。Abstract: One hundred primers were used to analyze the polymorphism of kinship of Sanjiang White pig and its parents, Landrace and Dongbei Min pig, Yorkshire, French Hybrids(Fh 019 strain),French Yorkshire by RAPD. Amplification results of 15 primers showed obvious polymorphisms, which were analyzed by clustering. The results indicate that the genetic relationship of Sanjiang White Pig, and Landrace, and Dongbei Min pig are respectively closer(d=0.090,,0.175), and that of Sanjiang White pig and Yorkshive(d=0.263), French Yorkshire(d = 0.223), Fh 019strain (d = 0.580) are respectively further.  相似文献   
234.
赵庆新ZHAO  Qing-xin 《遗传》2001,23(5):449-640
在同一背景条件下,对草鱼、白鲢、团头鲂和鲤鱼等4种鱼的肠道菌群中好氧性菌或兼性厌氧菌进行分析鉴定,得到4种鱼之间的肠道菌群相似值.用UPGMA和NJ法构建鲤科的雅罗鱼亚科、鲢亚科、鳊亚科和鲤亚科等4种亚科的系统演化树.不同亚科的鱼间菌群分布有较大差异,但雅罗鱼亚科和鳊亚科在菌群分布方面有极显著的正相关性.哈夫尼亚菌属、致病杆菌属、气单胞菌属、柠檬酸菌属、假单胞菌属等在4种鱼肠道中均有分布,链球菌属、拉恩氏菌属、芽孢杆菌属、葡萄球菌属等属于共生菌.雅罗鱼亚科和鳊亚科相邻邻接为一个共同接点,该接点与鲤亚科连接为一个接点,鲤亚科可能是最原始的类型。 Abstract:This paper is an analysis and appraisal of aerobe and facultative anaerobe among intestinal bacterium of the following fishes:Ctenophar yngodomidellus,Hypophtha lmichthys molitrix,Megalorama ambly cephala Yih and Cyprinus carpio haematopterus under same surroundings.After that,We contain similarity values of intestinal bacteria were obtained between every two kinds of the four fishes.We constructed the revolutionary trees of in Cyprinidate,Leuciscinae,Abramidinae,Cyprininae and Hypophthalmi by NJ method and UPGMA method according to the similarity values.  相似文献   
235.
Transfection of cDNA in 3'untranslated region of human nuclear factor for interleukin-6 (NF-IL6 3'UTR) induced tumor suppression in a human hepatoma cell line. cDNA array analysis was used to reveal changes in gene expression profile leading to tumor suppression The results indicate that this suppression was not due to activation of dsRNA-dependent protein kinase, nor to inactivation of oncogenes; rather, all the changes in expression of known genes, induced by NF-IL6 3'UTR cDNA may be ascribed to the suppression of cellular malignancy. Therefore, our results imply that this 3'untranslated region may have played role of a regulator of gene expression profile.  相似文献   
236.
目的:探讨根治性膀胱全切术后的最佳营养支持方法。方法:采用随机数法将60例根治性膀胱全切患者随机分为肠外营养支持(PNS)组和肠内营养支持组(ENS),比较两组患者的营养时间、术后下床时间以及住院时间、营养支持费用、血清总蛋白、白蛋白、前白蛋白以及术后并发症的发生情况。结果:术后7 d,ENS组血清总蛋白、白蛋白及前白蛋白均显著高于PNS组(p0.05)。ENS组的营养时间、术后下床时间以及住院时间均短于PNS组(P0.05),且营养支持费用少于PNS组(P0.05)。两组患者术后均未发生肠梗阻等手术相关并发症,PNS组发生静脉炎3例。结论:早期肠内营养是根治性膀胱全切患者术后理想的营养支持模式。  相似文献   
237.
研究了UV-C辐射下短期和长期脱落酸(ABA)处理对小麦幼苗CO2同化作用、羧化效率、光合CO2响应以及抗氧化酶活性等的影响.结果表明,在无UV-C辐射情况下,短期和长期ABA处理能提高光合速率,比对照增加14.69%和20.46%,降低气孔导度,比对照降低14.74%和17.31%,但对胞间CO2浓度和羧化效率影响不大.当受到UV-C辐射时,光合速率、羧化效率、气孔导度和胞间CO2浓度逐渐降低.长期ABA处理变化最小,其次为ABA短期处理,对照降低最大.ABA处理能够提高小麦光合对CO2的响应,UV-C辐射抑制光合对CO2的响应.ABA处理能够提高小麦抗氧化酶(CAT、SOD、POD)活性而降低MDA含量.在UV-C辐射下,CAT活性先升高随后降低,在辐射处理1 h时活性达最大值,ABA处理的SOD和POD活性先升高后降低,且ABA长期处理比短期处理增加明显,对照则逐渐降低.ABA处理可能通过提高小麦CO2同化作用和抗氧化酶活性增强对UV-C胁迫的抗性,且ABA长期处理比短期处理效果更明显.  相似文献   
238.
目的 通过文献数据挖掘与实验研究相结合的方法,挖掘洛哌丁胺诱导便秘小鼠模型造模特点及影响因素,为建立稳定的实验便秘模型提供一定参考.方法 文献研究部分以便秘及动物模型为主题词,检索中英文数据库,筛选使用洛哌丁胺诱导便秘小鼠模型的实验研究,提取资料并进行分析;动物实验部分,采用雄性C57BL/6小鼠,给予5 mg/kg及...  相似文献   
239.
Diverse a nimal species use multimodal communica tion signals to coordina te reproductive behavior.Despite active research in this field,the brain mechanisms underlying multimodal communication remain poorly understood.Similar to humans and many mammalian species,anurans often produce auditory signals accompanied by conspicuous visual cues(e.g.,vocal sac inflation).In this study,we used video playbacks to determine the role of vocal-sac inflation in little torrent frogs(Amolops torrentis).Then we exposed females to blank,visual,auditory,and audiovisual stimuli and analyzed whole brain tissue gene expression changes using RNAseq.The results showed that both auditory cues(i.e.,male advertisement calls)and visual cues were attractive to female frogs,although auditory cues were more attractive than visual cues.Females preferred simultaneous bimodal cues to unimodal cues.The hierarchical clustering of differentially expressed genes showed a close relationship between neurogenomic states and momentarily expressed sexual signals.We also found that the Gene Ontology terms and KEGG pathways involved in energy metabolism were mostly increased in blank contrast versus visual,acoustic,or audiovisual stimuli,indicating that brain energy use may play an important role in response to these stimuli.In sum,behavioral and neurogenomic responses to acoustic and visual cues are correlated in female little torrent frogs.  相似文献   
240.
激光显微切割(Laser microdissection,LMD)质谱(Mass spectrometry,MS)联用技术(LMD/MS)已成功应用于肾活检组织甲醛固定石蜡包埋切片的蛋白质组学研究,提高了某些肾脏病的诊断水平,显示出较好的临床应用前景。文中就LMD/MS蛋白质组学技术的原理、方法及该技术在肾淀粉样变性、膜增殖性肾小球肾炎等肾脏疾病的发病机制及诊断分型的应用进展进行综述。  相似文献   
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