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1.
This paper gives a quantitative analysis on the non-CO2 emissions related to energy demand, energy activities and land use change of six scenarios with different development pattern in 2030 and 2050 based on IPAC emission model. The various mitigation technologies and policies are assessed to understand the corresponding non-CO2 emission reduction effect. The research shows that the future non-CO2 emissions of China will grow along with increasing energy demand, in which thermal power and transportation will be the major emission and mitigation sectors. During the cause of future social and economic development, the control and mitigation of non-CO2 emissions is a problem as challenging and pressing as that of CO2 emissions.This study indicates that the energy efficiency improvement, renewable energy, advanced nuclear power generation, fuel cell, coal-fired combined cycle, clean coal and motor vehicle emission control technologies will contribute to non-CO2 emissions control and mitigation.  相似文献   
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The structural and functional aspects of two specific centromeres, one drawn from the animal kingdom (Drosophila) and the other from the plant kingdom (maize), are compared. Both cases illustrate an epigenetic component to centromere specification. The observations of neocentromeres in Drosophila and inactive centromeres in maize constitute one line of evidence for this hypothesis. Another common feature is the divisibility of centromere function with reduced stability as the size decreases. The systems differ in that Drosophila has no common sequence repeat at all centromeres, whereas maize has a 150-bp unit present in tandem arrays together with a centromere-specific transposon, centromere retrotransposon maize, present at all primary constrictions. Aspects of centromere structure known only from one or the other system might be common to both, namely, the presence of centromere RNAs in the kinetochore as found in maize and the organization of the centromeric histone 3 in tetrameric nucleosomes.  相似文献   
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Cheng Z  Wang J  Su D  Pan H  Huang G  Li X  Li Z  Shen A  Xie X  Wang B  Ma X 《Human genetics》2011,130(5):657-662
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The paper analyses total of 58 samples representing 32 species of the 14 genera of shrub plant of the carbon isotope composition in Xinjiang representatives of Chenopodiaceae and a detailed discussion on the various factors that can influence them. The value of 38 samples fall between ?14.88‰ and ?11.55‰ with a mean of ?13.34‰, and values of 20 samples between ?27.93‰ and ?22.877‰ with a mean of ?25.38‰. So we obtained a total of 21 of C4 species (59.4%) and 11 of C3 species (40.6%) from 32 species studied Chenopodiaceae of shrubs plant. Then the relationship of plant-carbon-isotope and environmental factors has been analyzed. The results showed that the importance environmental factors for the δ13C-value of the Shrubs was annual precipitation (0.78) > temperature (0.66) > elevation (0.55). The three principal components has important factors to influence on C3/C4 shrub plant distribution. Environmental conditions play significant roles in the distribution and ecophysiological features of different photosynthetic types and even change the photosynthetic pathways. On the other hand, such as geographic location, Sunshine duration, evaporation capacity are more or less correlation with δ13C values, however, they would be interfered by annual precipitation. Desert plants to adapt to drought conditions by increasing water use efficiency (WUE) strategy. In short, plant physiology function is sensitive and timely to adapt environmental change.  相似文献   
6.
Insulin-like growth factor-I receptor (IGF-IR) is important for maintaining proliferation and apoptosis in osteoblasts. However, the details about the effect of sodium fluoride supplementation on primary osteoblast cultures on mediating IGF-IR expression are still not well-known. In this study, we used mouse osteoblasts to examine the impact of sodium fluoride on the proliferation and apoptosis; the cells were treated with IGF-IR small interfering RNA (or left untreated) and subsequently divided into a control group and six experimental groups, which were exposed to different concentrations of NaF (10(-6), 10(-5), 10(-4), 10(-3), 5?×?10(-3), and 10(-2)?mol/L) for analysis at 48?h. In particular, we examined cell proliferation, apoptosis, IGF-IR messenger RNA, and protein expression levels of the various cell groups. In summary, our findings suggest that the administration of NaF affects the expression of IGF-IR in mouse osteoblasts, contributing to the proliferation and apoptosis induced by fluoride.  相似文献   
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Hyperhomocysteinemia (Hhcy) may induce memory deficits with β‐amyloid (Aβ) accumulation and tau hyperphosphorylation. Simultaneous supplement of folate and vitamin B12 partially restored the plasma homocysteine level and attenuated tau hyperphosphorylation, Aβ accumulation and memory impairments induced by Hhcy. However, folate and vitamin B12 treatment have no effects on Hhcy which has the methylenetetrahydrofolate reductase genotype mutation. In this study, we investigated the effects of simultaneous supplement of betaine on Alzheimer‐like pathological changes and memory deficits in hyperhomocysteinemic rats after a 2‐week induction by vena caudalis injection of homocysteine (Hcy). We found that supplementation of betaine could ameliorate the Hcy‐induced memory deficits, enhance long‐term potentiation (LTP) and increase dendritic branches numbers and the density of the dendritic spines, with up‐regulation of NR1, NR2A, synaptotagmin, synaptophysin, and phosphorylated synapsin I protein levels. Supplementation of betaine also attenuated the Hcy‐induced tau hyperphosphorylation at multiple AD‐related sites through activation protein phosphatase‐2A (PP2A) with decreased inhibitory demethylated PP2AC at Leu309 and phosphorylated PP2AC at Tyr307. In addition, supplementation of betaine also decreased Aβ production with decreased presenilin‐1 protein levels. Our data suggest that betaine could be a promising candidate for arresting Hcy‐induced AD‐like pathological changes and memory deficits.  相似文献   
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目的:建立可快速检测化学物致敏性和刺激性的局部淋巴结试验( LLNA:BrdU-ELISA)改良法,并对化妆品产品进行评价。方法3种化学物(2,4二硝基氯苯( DNCB)、丁子香酚、己基肉桂醛)和3种化妆品产品作为受试物,雌性BALB/c小鼠连续染毒3天,测量小鼠耳缘厚度,第5天腹腔注射BrdU,第6天称耳廓重,分离颌下淋巴结称重并制取单细胞悬液,用ELISA试剂盒检测淋巴细胞增殖。结果 DNCB(1.0%)、己基肉桂醛(25%、50%)和3号粉底霜引起耳肿胀和耳廓重显著增加(P <0.05或P <0.01),可能为刺激物,其他均无刺激性;3种化学物和3号粉底霜致敏检测阳性,其他均为阴性。结论结合小鼠耳肿胀和耳廓重的LLNA:BrdU-ELISA改良法可较好地评价化学物和化妆品产品的致敏性和刺激性,有望在化妆品安全性评价中发挥重要作用。  相似文献   
10.
[目的]雄蜂对蜂群繁衍有着非常重要的作用.本研究旨在探究吡虫啉对意大利蜜蜂Apis mellifera Ligustica雄蜂生长发育和基因表达产生的影响.[方法]以意大利蜜蜂雄蜂为研究对象,分别以0.00001、0.0001和0.001 μg/μL浓度的吡虫啉对雄蜂幼虫进行连续饲喂处理.每天观察并记录幼虫的发育形态及死亡率,在雄蜂幼虫后期(移虫后6d)测量幼虫体重.利用Illumina HiSeq测序技术对经吡虫啉处理的雄蜂进行转录组测序,进而对差异表达基因进行深入分析.[结果]取食吡虫啉后的雄蜂幼虫,体重低于正常雄蜂,当浓度高于0.0001μg/μL时差异显著;雄蜂幼虫取食吡虫啉后出现死亡现象,且死亡率随吡虫啉浓度的升高而增大;差异表达基因分析结果上调与下调基因数量分别为390个和130个.GO富集分析结果上调基因共分布于55个GO条目,富集基因数量最多的是细胞进程、细胞、细胞组件、细胞膜、细胞膜组件、结合,下调基因共分布于48个GO条目,富集基因数量最多的是细胞进程、细胞、细胞组件.富集在有关生殖功能的差异表达基因中,上调基因数量为21个,下调基因数量为5个.KEGG代谢通路富集分析结果上调基因富集在159个通路上,其中富集基因数最多的是蛋白质消化吸收和神经活性配体-受体相互作用通路.下调基因富集在71个通路上,其中富集基因数最多的是溶酶体、胰液分泌、神经活性配体-受体相互作用通路.[结论]吡虫啉能抑制意大利蜜蜂雄蜂的生长发育,甚至造成幼虫死亡,同时,可以影响雄蜂的神经系统、代谢系统和生殖系统等.本研究结果为蜜蜂资源保护提供理论依据.  相似文献   
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