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抑制差减杂交法克隆牙鲆变态早期差异表达的基因 被引量:6
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作者 鲍宝龙 杨桂梅 +1 位作者 施志仪 任大明 《水产学报》 CAS CSCD 北大核心 2006年第2期204-210,共7页
为了克隆变态早期牙鲆头部差异表达的基因,采用抑制差减杂交法,以变态前的仔鱼头部表达的RNA作为驱动RNA,建立了牙鲆变态早期的差减cDNA文库,并利用相对定量RT-PCR对其进行了筛选。差减库的平均插入片段558bp左右,阳性率为81.8%。随机... 为了克隆变态早期牙鲆头部差异表达的基因,采用抑制差减杂交法,以变态前的仔鱼头部表达的RNA作为驱动RNA,建立了牙鲆变态早期的差减cDNA文库,并利用相对定量RT-PCR对其进行了筛选。差减库的平均插入片段558bp左右,阳性率为81.8%。随机测定的45个克隆,在剔除假阳性克隆后,共得到22个不同的基因,其中13个为已知cDNA的同源基因,而另外9个为已知蛋白的同源基因,分别为prolactin receptor-like,COL1A1,M-3muscarinic receptor,Sfrs3,tropomyosin,ribosomal protein L27,ribosomal protein S12,GAPDH,COL1A3。在所有22个基因中,COL1A1基因在差减库中的分布频率最高,为22.2%。RT-PCR检测结果表明,在所检测的11个基因中,所有基因在右眼移动前后的牙鲆头部均有表达,只是体现在表达水平上的不同。 展开更多
关键词 抑制差减杂交 牙鲆 变态早期 变态 差异表达 相对定量RT-PCR
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调控蝌蚪变态 提高牛蛙越冬成活率
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作者 包乐天 《农业装备技术》 1997年第1期21-21,共1页
关键词 蝌蚪变态 动物性饵料 牛蛙 降低水温 越冬 日光温室 控制方法 变态幼蛙 越冬成活率 前变态
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Morphological changes of silver and bighead carp in the Yangtze River over the past 50 years 被引量:2
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作者 于红霞 唐文乔 李思发 《Zoological Research》 CAS CSCD 北大核心 2010年第6期651-656,共6页
Multivariate analysis was adopted to analyze 30 morphometrical characteristics of 121 one-year-old juvenile silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) bred during the 1950s ... Multivariate analysis was adopted to analyze 30 morphometrical characteristics of 121 one-year-old juvenile silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) bred during the 1950s ("the former population") and 2008 ("the current population") and collected from the middle reach of the Yangtze River. The average discriminant accuracies of the former and current silver and bighead carp population were 94.2% and 98.0%, respectively. Discriminant analysis also revealed that significant differences in morphology occurred between the former and current populations of both carp in overall characteristics. One-way analysis of variance indicated that between former and current populations, silver carp showed highly significant differences (P0.01) in twelve of their characteristics and significant differences (P0.05) in eight of their characteristics, while bighead carp showed highly significant differences (P0.01) in eight of their characteristics and significant differences (P0.05) in eight of their characteristics. Six head morphology variables of the current silver and bighead carp were significantly or highly significantly larger than the former populations; fourteen characteristics of silver carp and ten characteristics of bighead carp of the current populations, mainly reflecting truck and tail morphology, were significantly or very significantly smaller than the former populations. Our results indicate that silver and bighead carp have developed a larger head and smaller truck and tail during the last 50 years. Due to such morphological changes, it seems apparent that the heads of these fish species need to be considered in regards to human diets, particularly in relation to economic and nutritious value. 展开更多
关键词 Silver carp Bighead carp 50 years breeding Morphological change Yangtze River
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对抑郁研究方法的可行性评价
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作者 梁建春 《医学与哲学(A)》 1992年第10期46-46,共1页
目前,人们从社会、心理学的角度对抑郁进行的研究,很多是在控制了并发症的条件下,就抑郁与某一个重要的变量之间的关系进行的探讨,这些研究方法仍是可行的。比如,从横向研究来说,把抑郁组的被试和正常的控制组被试在抑郁情节期间和抑郁... 目前,人们从社会、心理学的角度对抑郁进行的研究,很多是在控制了并发症的条件下,就抑郁与某一个重要的变量之间的关系进行的探讨,这些研究方法仍是可行的。比如,从横向研究来说,把抑郁组的被试和正常的控制组被试在抑郁情节期间和抑郁恢复之后进行比较,这种研究虽然不适合对抑郁病因进行单向的因果推断,但至少能证明在抑郁情节期间。 展开更多
关键词 被试 横向研究 控制组 与某 可行性评价 研究方法 追踪研究 个体差异 纵向研究 前变态
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The Characteristics of the Precursory Anomaly prior to the Yiliang Earthquakes,Yunnan,China on September 7,2012
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作者 Sun Zongqiang Shi Yafang +6 位作者 Gao Huayan Rui Wenjun Feng Liangliang Xu Fangfang Cao Xiaoli Wang Bin Wang Yongmei 《Earthquake Research in China》 2014年第2期250-260,共11页
An analysis was carried out on the seismic activity and the precursory anomaly prior to the earthquakes in Yiliang on September 7,2012. The characteristics of the seismic activity,the dynamic changes of underground fl... An analysis was carried out on the seismic activity and the precursory anomaly prior to the earthquakes in Yiliang on September 7,2012. The characteristics of the seismic activity,the dynamic changes of underground fluid and deformation were investigated. As a result of the investigation,we found that: before the earthquake,the seismicity level of M4. 0earthquakes had enhanced,and seismic gap of a small earthquake had appeared; the precursory anomalies emerged about 1 year before the earthquake; there was phenomenon of short-term anomaly migrating from the periphery to the epicenter area; the imminent anomaly appeared in a relatively concentrated period of time, a week before the earthquake. The research has shown a significant guidance for the analysis and prediction of strong earthquakes( Ml> 5. 0). 展开更多
关键词 Yiliang earthquake Seismicity anomaly Precursor anomaly
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Dynamic Variations of the Gravity Field before and after the M5. 1 Wen’an Earthquake in Hebei Province
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作者 Wang Wuxing Shi Yaolin +1 位作者 Zhang Jing Shi Yanhua 《Earthquake Research in China》 2010年第1期22-30,共9页
In order to explore the abnormal variations before and after the Wen'an MS. 1 earthquake on July 4, 2006, the gravity data observed by the Wenba Gravity Observation Network before and after the earthquake was analyze... In order to explore the abnormal variations before and after the Wen'an MS. 1 earthquake on July 4, 2006, the gravity data observed by the Wenba Gravity Observation Network before and after the earthquake was analyzed. The relationships between gravity change and vertical displacement and shallow groundwater level were discussed, and elevation correction of the gravity was preliminarily performed. The results show that there were abnormal gravity changes before the MS. ! earthquake, which appeared as gravity rising in the whole observation network, especially in the south part. A high gradient of gravity variation appeared around the epicenter before the MS. 1 earthquake, especially during the short period between October 2005 to April 2006. The boundary of the positive and negative gravity variations gradually deflected and began to recover from October 2007. 展开更多
关键词 Wen'an earthquake Wenba Gravity Observation Network Dynamic gravity change
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The Dynamic Characteristics of Strain Fields and Crustal Movement before the Wenchuan Earthquake (M_S=8.0) 被引量:1
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作者 Jiang Zaisen Wu Yanqiang Fang Ying Li Peng Wang Wuxing 《Earthquake Research in China》 2009年第3期257-265,共9页
In this paper, we analyze the crustal movements, strain field changes and large scale dynamic characteristics of horizontal deformation before the Wenchuan earthquake ( Ms = 8.0) using GPS data obtained from the Cru... In this paper, we analyze the crustal movements, strain field changes and large scale dynamic characteristics of horizontal deformation before the Wenchuan earthquake ( Ms = 8.0) using GPS data obtained from the Crustal Movement Observation Network of China. The following issues are discussed. First, the strain fields of the Longmeushan fault zone located at the epicenter show slow accumulation, because of the tectonic dynamics process subjected to the eastward movement of the Bayan Har block. Second, the different movements between the Longmenshan fault and South China block are smaller than the errors of GPS observation. Third, the high value of compressive strain (2004 - 2007) is located at the epicenter, which shows that the local squeezing action is stronger than before. Fourth, the data from GPS reference stations in the Chinese Mainland show that crustal shortening is faster than before in the north-eastern direction, which is part of the background of the local tectonic dynamics increase in the Longmenshan fault zone. 展开更多
关键词 Wenchuan earthquake Ms = 8.0 GPS Crustal movement Strain field Tectonic dynamics background
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