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Yang Su-Rong Sun Huan-Xin Hu Zhen-Zhen Wang Si-Heng Sun Hui Xue Yin-Jia Ye Chen-Bo 《Sleep and biological rhythms》2017,15(1):57-65
Sleep and Biological Rhythms - Chronic sleep deprivation (SD) is an overwhelming problem in young students. Firstly, we investigated whether different levels of pre-training SD had effects on... 相似文献
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Genome‐wide detection of CNVs associated with beak deformity in chickens using high‐density 600K SNP arrays
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H. Bai Y. Sun N. Liu Y. Liu F. Xue Y. Li S. Xu A. Ni J. Ye Y. Chen J. Chen 《Animal genetics》2018,49(3):226-236
Beak deformity (crossed beaks) is found in several indigenous chicken breeds including Beijing‐You studied here. Birds with deformed beaks have reduced feed intake and poor production performance. Recently, copy number variation (CNV) has been examined in many species and is recognized as a source of genetic variation, especially for disease phenotypes. In this study, to unravel the genetic mechanisms underlying beak deformity, we performed genome‐wide CNV detection using Affymetrix chicken high‐density 600K data on 48 deformed‐beak and 48 normal birds using penncnv . As a result, two and eight CNV regions (CNVRs) covering 0.32 and 2.45 Mb respectively on autosomes were identified in deformed‐beak and normal birds respectively. Further RT‐qPCR studies validated nine of the 10 CNVRs. The ratios of six CNVRs were significantly different between deformed‐beak and normal birds (P < 0.01). Within these six regions, three and 21 known genes were identified in deformed‐beak and normal birds respectively. Bioinformatics analysis showed that these genes were enriched in six GO terms and one KEGG pathway. Five candidate genes in the CNVRs were further validated using RT‐qPCR. The expression of LRIG2 (leucine rich repeats and immunoglobulin like domains 2) was lower in birds with deformed beaks (P < 0.01). Therefore, the LRIG2 gene could be considered a key factor in view of its known functions and its potential roles in beak deformity. Overall, our results will be helpful for future investigations of the genomic structural variations underlying beak deformity in chickens. 相似文献
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Social responsibility links personal behavior with societal expectations and plays a key role in affecting an agent’s emotional state following a decision. However, the neural basis of responsibility attribution remains unclear. In two previous event-related brain potential (ERP) studies we found that personal responsibility modulated outcome evaluation in gambling tasks. Here we conducted a functional magnetic resonance imaging (fMRI) study to identify particular brain regions that mediate responsibility attribution. In a context involving team cooperation, participants completed a task with their teammates and on each trial received feedback about team success and individual success sequentially. We found that brain activity differed between conditions involving team success vs. team failure. Further, different brain regions were associated with reinforcement of behavior by social praise vs. monetary reward. Specifically, right temporoparietal junction (RTPJ) was associated with social pride whereas dorsal striatum and dorsal anterior cingulate cortex (ACC) were related to reinforcement of behaviors leading to personal gain. The present study provides evidence that the RTPJ is an important region for determining whether self-generated behaviors are deserving of praise in a social context. 相似文献
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人体小卫星DNA探针的制备 总被引:3,自引:2,他引:1
根据人体小卫星DNA核心顺序,化学合成长23碱基寡核苷酸探针,筛选人体基因组文库,旨在获得能用作遗传分析探针的小卫星顺序。结果得到15个含小卫星的阳性重组子。随机取其一(C_(35.9))作探针,试做群体分析。所有个体均可检出多条杂交带。其中某些带具有多态性。在一定检测条件下,检出的DNA图谱在有限的个体内具有个体特异性。结果表明筛选文库得到的小卫星顺序可用于小卫星多态性的检测。其它小卫星探针的筛选和应用性研究正在进行。 相似文献
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我们曾观察到大鼠经γ-射线照射后胰淀粉酶活性降低和分泌减少[1],为进一步探讨照射后胰酶分泌减少的机制,本研究制备出分散的大鼠胰腺腺泡悬液并以不同浓度的~3H-二苯羟乙酸-3-喹咛环酯(~3Hquinuclidinyll benzilatc,简称~3H-QNB)进行M受体结合测定,同时观察胆碱能介质氨甲酰胆碱刺激腺泡所引起的淀粉酶释放反应。结果表明,γ-射线10Gy照射后3天,大鼠分散的胰腺腺泡在氨甲酰胆碱刺激时淀粉酶释放量减少到对照的50%,腺泡M受体与~3H-QNB最大结合量(Bmax)减少到对照的38%,伋M受体与~3H-QNB结合的解离常数(K_D)无改变,说明胰腺腺泡细胞M受体数量的减少可能是照射后胰腺腺泡分泌淀粉酶减少的原因之一。 相似文献
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Catalytic properties of chloroplast F1-ATPase modified at catalytic or noncatalytic sites by 2-azido adenine nucleotides 总被引:1,自引:0,他引:1
When heat-activated F1-ATPase from chloroplasts was repeatedly exposed to Mg2+ and 2-azido-ATP, followed by separation from medium nucleotides and photolysis, a total of two sites per enzyme, both catalytic and noncatalytic, were labeled. In a coupled assay with pyruvate kinase about half the activity was lost when one site per enzyme was modified. However, increased modification resulted in no further loss of activity. In contrast, methanol-sulfite activation of the enzyme showed a loss of most of the catalytic capacity when one site per enzyme was modified. Predominant labeling of either one catalytic or one noncatalytic site caused a loss of most of the activity in either assay. An indication that the enzyme modified at one site retained some catalytic activity was verified by measurement of the [18O]Pi species formed when [gamma-18O]ATP was hydrolyzed by partially derivatized enzyme. With either catalytic or noncatalytic site modification, the distributions of [18O]Pi species formed showed that the modified enzyme had different catalytic characteristics. An interpretation is that with modification by azido nucleotides at either catalytic or noncatalytic sites, capacity for rapid catalysis is largely lost but the remaining sites retain weak modified catalytic properties. 相似文献
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A S Edelman B Xue P Sanchez G J Thorbecke 《Journal of immunology (Baltimore, Md. : 1950)》1985,135(3):2206-2212
Dimethylbenz[a]anthracene (DMBA)-induced transplantable fibrosarcomas in B2 homozygous chickens (SC line) grow progressively in normal chickens, but are rejected by chickens immunized previously with irradiated tumor cells and Corynebacterium parvum. Tumor-immune chickens resist challenge by the immunizing tumor lines as well as by some, but not all, fibrosarcoma lines. The pattern of cross-reactivity between four DMBA-induced transplantable tumor lines was examined in detail. Ability to reject a tumor challenge correlated very well (p less than 0.001) with the presence of delayed-type hypersensitivity (DTH) to that tumor. Immunization with one of two of the DMBA-induced lines tested also caused rejection of transplantable tumors developed from methylcholanthrene-induced and benzo(a)pyrene-induced primary fibrosarcomas. Although immunization with tumor caused DTH to chicken embryo fibroblasts (CEF), immunization with CEF failed to cause protective immunity or DTH to tumors. Presence of protective immunity, where tested, also correlated with the ability of spleen cells from immune donors to inhibit tumor growth in Winn tests. Humoral immunity exhibited even greater cross-reactivity than did cellular immunity. Distinct patterns of cross-reactivity were nevertheless observed with respect to the serum antibodies as detected in ELISA. Two of these patterns were also observed in several sera from primary tumor-bearing chickens, both including reactivity with CEF. Such reactivity was absent from normal chicken sera. 相似文献