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841.
Attention‐deficit hyperactivity disorder (ADHD) is one of the most common neuropsychiatric disorders in children and adolescents with high heritability. Evidence is accumulating that SLC1A3 may play a role in ADHD etiology. Therefore, a two‐stage case‐control study was conducted on 752 cases and 774 controls to explore the role of SLC1A3 in ADHD. Bioinformatic annotations and functional experiments were applied to reveal the potential biological mechanisms. Finally, SLC1A3 rs1049522 showed significant association with ADHD risk in two stages with CA genotype vs AA genotype, odds ratio (OR) = 0.694 (95% confidence interval, CI = 0.570‐0.844) and dominant model, OR = 0.749 (95% CI = 0.621‐0.904) in the combined stage. Besides, rs1049522 was found to be related to ADHD hyperactive/impulsive symptom, and rs1049522‐C showed increased SLC1A3 mRNA expression in the cerebellar cortex. Dual‐luciferase reporter assay further indicated that rs1049522‐C allele enhanced SLC1A3 expression by disrupting the hsa‐miR‐3171 binding site. In conclusion, SLC1A3 variant rs1049522 was implicated in ADHD susceptibility in a Chinese Han population probably by enhancing the SLC1A3 expression in a miRNA‐mediated manner.  相似文献   
842.
Morphometric variation among populations of Sarotherodon melanotheron melanotheron across its natural range (Mahin, epe, Lekki, Apese, Kuramo, Lagos, Iyagbe, Ologe, Badagry, Yewa – Nigeria; Be Lagoon – Togo; Idenau – Cameroon, Aheme – Benin; Portonovo – Benin) were studied to assess the level of differentiation of one of the populations that is currently isolated from the rest, the Apese Lagoon population. S. m. melanotheron showed subtle differentiation from some of the other lagoon populations. However, the pattern of variation did not reflect the level of geographical barriers or geographical distance among populations. The characters that form the basis of the differentiation observed were mostly those related to feeding, vision and respiration.  相似文献   
843.
Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system.  相似文献   
844.
Chronic myeloid leukemia (CML) is a lethal malignancy, and the progress toward long‐term survival has stagnated in recent decades. Pristimerin, a quinone methide triterpenoid isolated from the Celastraceae and Hippocrateaceae families, is well‐known to exert potential anticancer activities. In this study, we investigated the effects and the mechanisms of action on CML. We found that pristimerin inhibited cell proliferation of K562 CML cells by causing G1 phase arrest. Furthermore, we demonstrated that pristimerin triggered autophagy and apoptosis. Intriguingly, pristimerin‐induced cell death was restored by an autophagy inhibitor, suggesting that autophagy is cross‐linked with pristimerin‐induced apoptosis. Further studies revealed that pristimerin could produce excessive reactive oxygen species (ROS), which then induce JNK activation. These findings provide clear evidence that pristimerin might be clinical benefit to patients with CML.  相似文献   
845.
Developing advanced supercapacitors with both high areal and volumetric energy densities remains challenging. In this work, self‐supported, compact carbon composite electrodes are designed with tunable thickness using 3D printing technology for high‐energy‐density supercapacitors. The 3D carbon composite electrodes are composed of the closely stacked and aligned active carbon/carbon nanotube/reduced graphene oxide (AC/CNT/rGO) composite filaments. The AC microparticles are uniformly embedded in the wrinkled CNT/rGO conductive networks without using polymer binders, which contributes to the formation of abundant open and hierarchical pores. The 3D‐printed ultrathick AC/CNT/rGO composite electrode (ten layers) features high areal and volumetric mass loadings of 56.9 mg cm?2 and 256.3 mg cm?3, respectively. The symmetric cell assembled with the 3D‐printed thin GO separator and ultrathick AC/CNT/rGO electrodes can possess both high areal and volumetric capacitances of 4.56 F cm?2 and 10.28 F cm?3, respectively. Correspondingly, the assembled ultrathick and compact symmetric cell achieves high areal and volumetric energy densities of 0.63 mWh cm?2 and 1.43 mWh cm?3, respectively. The all‐component extrusion‐based 3D printing offers a promising strategy for the fabrication of multiscale and multidimensional structures of various high‐energy‐density electrochemical energy storage devices.  相似文献   
846.
Two new nonfullerene small molecule acceptors (NF‐SMAs) AT‐NC and AT‐4Cl based on heptacyclic anthracene(cyclopentadithiophene) (AT) core and different electron‐withdrawing end groups are designed and synthesized. Although the two new acceptor molecules use two different end groups, naphthyl‐fused indanone (NINCN) and chlorinated INCN (INCN‐2Cl) demonstrate similar light absorption. AT‐4Cl with chlorinated INCN as end groups are shifted significantly due to the strong electron‐withdrawing ability of chlorine atoms. Thus, desirable Voc and photovoltaic performance are expected to be achieved when polymer PBDB‐T is used as the electron donor with AT‐NC as the acceptor, and fluorinated analog PBDB‐TF with down‐shifted energy levels is selected to blend with AT‐4Cl. Consequently, the device based on PBDB‐TF:AT‐4Cl yields a high power conversion efficiency of 13.27% with a slightly lower Voc of 0.901 V, significantly enhanced Jsc of 19.52 mA cm?2 and fill factor of 75.5% relative to the values based on PBDB‐T:AT‐NC. These results demonstrate that the use of a new electron‐rich AT core, together with energy levels modulations by end‐group optimizations enabling the match with polymer donors, is a successful strategy to construct high‐performance NF‐SMAs.  相似文献   
847.
Zhang  Hai-Feng  Zhang  Hao  Yang  Jing  Li  Hai-Ming 《Plasmonics (Norwell, Mass.)》2019,14(4):985-991
Plasmonics - In this paper, we propose a three-dimensional tunable absorber to realize a controllable unidirectional absorption and unidirectional transmission based on the plasma metamaterial,...  相似文献   
848.
Fabrication of efficient Pb reduced inorganic CsPbI2Br perovskite solar cells (PSC) are an important part of environment‐friendly perovskite technology. In this work, 10% Pb reduction in CsPb0.9Zn0.1I2Br promotes the efficiency of PSCs to 13.6% (AM1.5, 1sun), much higher than the 11.8% of the pure CsPbI2Br solar cell. Zn2+ has stronger interaction with the anions to manipulate crystal growth, resulting in size‐enlarged crystallite with enhanced growth orientation. Moreover, the grain boundaries (GBs) are passivated by the Cs‐Zn‐I/Br compound. The high quality CsPb0.9Zn0.1I2Br greatly diminishes the GB trap states and facilitates the charge transport. Furthermore, the Zn4s‐I5p states slightly reduce the energy bandgap, accounting for the wider solar spectrum absorption. Both the crystalline morphology and energy state change benefit the device performance. This work highlights a nontoxic and stable Pb reduction method to achieve efficient inorganic PSCs.  相似文献   
849.
KLF8(Krüppel-like factor 8)是Krüppel 样转录因子家族最新成员。KLF8广泛表达于皮肤、脂肪、食道等组织中。早期研究表明,KLF8蛋白具有转录抑制活性,在胚胎发育过程中起重要作用。而近些年大量的研究发现KLF8在多种肿瘤组织中异常高表达,具有转录活化因子活性,可通过对细胞增殖、迁移、侵袭、EMT、细胞干性等多项生理过程调控促进肿瘤发生发展。综述了近年来KLF8研究进展,系统阐述了KLF8表达修饰调控及致瘤机制,为全面深入了解KLF8在肿瘤中作用及后续相关研究提供参考。  相似文献   
850.
建立多重液相基因芯片方法快速检测狐狸、水貂成分   总被引:1,自引:0,他引:1  
基于xMAP液相芯片新型生物技术平台,分别以狐狸线粒体DNA D-loop区序列、水貂线粒体DNA细胞色素b基因序列为模板设计特异扩增引物和探针,并对探针进行锁核酸修饰,建立了二重xMAP液相基因芯片方法,用于快速检测狐狸和水貂源性成分。该法能准确鉴定鉴别狐狸和水貂DNA,对其他18种动物物种DNA均呈检测阴性,对狐狸、水貂DNA的检测低限分别为2. 8pg/μl、0. 9pg/μl,对肉类混样检出限为0. 05%(m/m)。对目标源性DNA含量为1%(V/V)的32份饲料与食品核酸添加样本均呈对应目标检测阳性。结果表明,该方法特异性强、灵敏度高,适用于食品与饲料领域相关原料和产品的质量与安全检验。  相似文献   
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