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1.
利用RT-PCR方法扩增了猪ERK6基因编码区的序列,将扩增产物与pMD18-T载体连接,构建了重组质粒;重组质粒经PCR、酶切鉴定后进行测序;采用Northern杂交和半定量RT-PCR方法在猪不同部位骨骼肌中分析了ERK6基因转录本的个数、大小及组织表达谱。结果显示,所克隆的猪ERK6基因片段长1 113 bp,含有1个1 104 bp的开放阅读框(ORF),该ORF编码367个氨基酸;该基因与已报道的人ERK6基因核苷酸序列相似性为90%;猪ERK6基因在肌肉组织中只有一个转录本,大小约1.5 kb。此基因在骨骼肌中的表达量最高,心、子宫次之,卵巢最低;而在脂肪、胃、肝、脾、肺、肾、十二指肠和胰腺中未见表达。结果表明,猪ERK6基因与已报道的小鼠和人ERK6基因一样,主要在骨骼中特异表达。  相似文献   
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Links between schools’ demographic composition and students’ achievement have been a major policy interest for decades. Using a racially/ethnically diverse sample from the National Longitudinal Study of Adolescent Health (N = 6,302; 54 % females; 53 % White, 21 % African American, 15 % Latino, 8 % Asian American, 2 % other race/ethnicity), we examined the associations between demographic marginalization, students’ later social integration (loneliness at school, school attachment), and educational performance and attainment. Adolescents who were socioeconomically marginalized at school [i.e., having <15 % same-socioeconomic status (SES) peers] had lower cumulative grade point averages across high school and lower educational attainment. A similar disadvantage was observed among students who were both socioeconomically and racially/ethnically marginalized at school (i.e., having <15 % same-SES peers and <15 % same-racial/ethnic peers). Indirect effects were also observed, such that demographic marginalization was linked to poorer school attachment, and poorer school attachment, in turn, was related to poorer academic performance. These results highlight the educational barriers associated with demographic marginalization and suggest potential targets for future intervention efforts.  相似文献   
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The transition to high school is disruptive for many adolescents, yet little is known about the supportive relational processes that might attenuate the challenges students face as they move from middle to high school, particularly for students from more diverse backgrounds. Identifying potential buffers that protect youth across this critical educational transition is important for informing more effective support services for youth. In this study, we investigated how personal characteristics (gender, nativity, parent education level) and changes in support from family, friends, and school influenced changes in socioemotional adjustment and academic outcomes across the transition from middle to high school. The data were drawn from 252 students (50% females, 85% Latina/o). The results revealed declines in students’ grades and increases in depressive symptoms and feelings of loneliness across the high school transition, with key variation by student nativity and gender. Additionally, stable/increasing friend support and school belonging were both linked to less socioemotional disruptions as students moved from middle to high school. Increasing/stable school belonging was also linked to increases in school engagement across the high school transition. These findings suggest that when high school transitions disrupt supportive relationships with important others in adolescents’ lives, adolescents’ socioemotional well-being and, to a lesser extent, their academic engagement are also compromised. Thus, in designing transition support activities, particularly for schools serving more low-income and race/ethnic minority youth, such efforts should strive to acclimate new high school students by providing inclusive, caring environments and positive connections with educators and peers.  相似文献   
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YANG Jie, 23, starts work at his office on Youth Road in Wuhan, Hubei Province at 9 am each day and returns to his dorm to sleep at 10 pm. He eats a modest lunch in the small restaurant downstairs and has a takeaway for supper. It was in the summer of 2005 that Yang Jie and Li Chao opened their Qi Hang Advertising Company. Their small firm deals with large and small concerns alike, and in order to stay solvent, they spend their lives either at the office, where they deal with clients an…  相似文献   
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二战结束至今,日朝之间仍未建立外交关系,因此,两国又被称作“近而远的国家”。目前,战争赔偿问题、日本人绑架问题、导弹发射及出售问题已成为日朝恢复邦交关系的一些障碍因素。尤其是朝核问题成为今后相当长一段时期影响日朝关系的一个主要因素。  相似文献   
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This paper discusses results of a supercritical fluid extraction-gas chromatography/mass spectrometry (SFE-GC/MS) study of small samples ( 100 microg to 1 mg) of human scalp hair. The method offers a number of benefits including greater sensitivity than liquid extraction methods because the entire extractable mass is transferred to the analytical system, compared with only a few percent from a conventional liquid extraction/injection. The project's goals were to determine if SFE-GC/MS analyses of the surface-extractable components of an individual's hair yield consistent chemical profiles and to investigate if the profiles are sufficiently different to distinguish them from those of other individuals. In addition, the mtDNA sequences from ten of the same individuals used in the SFE-GC/MS study from four family units were determined, and, while the families were distinguishable, the maternal relations yielded identical sequences. In tandem, SFE-GC/MS and mtDNA techniques may provide valuable complementary data from forensic hair samples.  相似文献   
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进入20世纪80年代以后,作为经济强国的日本已经不再满足于“经济大国政治小国”的地位,历届内阁开始要求与经济大国地位相适应的政治大国地位。日本政府在寻求实现政治大国目标的过程中,主要选择了以军事领域作为突破口,以成为军事大国带动政治大国目标的实现。具体体现在强化日美同盟、建立和完善有事法制、保持自主、高效的自卫力量与积极参与联合国维和行动四个方面。  相似文献   
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Research in many forensic science fields commonly uses domestic pigs (Sus spp.) as proxies for human remains, due to their physiological and anatomical similarities, as well as being more readily available. Unfortunately, previous research, especially that which compares the decompositional process, has shown that pigs are not appropriate proxies for humans. To date, there has not been any published research that specifically addresses whether domestic pigs are adequate human proxies for the geophysical detection of clandestine graves. As such, the aim of this paper was to compare the geophysical responses of pig cadavers and human donor graves, in order to determine if pigs can indeed be used as adequate human proxies. To accomplish this, ground penetrating radar (GPR) and electrical resistivity tomography (ERT) responses on single and multiple pig cadaver graves were compared to single and multiple human donor graves, all of which are in known locations within the same geological environment. The results showed that under field conditions, both GPR and ERT were successful at observing human and pig burials, with no obvious differences between the detected geophysical responses. The results also showed that there were no differences in the geophysical responses of those who were clothed and unclothed. The similarity of the responses may reflect that the geophysical techniques can detect graves despite what their contents are. The study implications suggest that experimental studies in other soil and climate conditions can be easily replicated, benefiting law enforcement with missing persons cases.  相似文献   
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