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51.
Previous research suggests that female sex hormones can increase the sensitivity of women's emotion processing systems. The largest rises in sex hormone levels in a woman's life are from early to late pregnancy. The current study, therefore, investigated whether changes in emotion processing are seen across pregnancy. Hypervigilant emotion processing has been implicated in the aetiology of anxiety. Therefore enhanced emotion processing across pregnancy has implications for women's vulnerability to anxiety. Ability to encode facial expressions of emotion was assessed in 101 women during early pregnancy and again in 76 of these women during late pregnancy. Symptoms of anxiety were measured using a clinical interview (The CIS-R). Consistent with previous research, the presence of anxiety symptoms was associated with greater accuracy to encode faces signalling threat (fearful and angry faces). We found that women had higher accuracy scores to encode emotional expressions signalling threat or harm (fearful, angry and disgusted faces) but also a more general negative emotion (sadness) during late, compared with early, pregnancy. Enhanced ability to encode emotional faces during late pregnancy may be an evolutionary adaption to prepare women for the protective and nurturing demands of motherhood by increasing their general emotional sensitivity and their vigilance towards emotional signals of threat, aggression and contagion. However, the results also suggest that, during late pregnancy, women's emotion processing style is similar to that seen in anxiety. The results have implications for our understanding of normal pregnant women's processing of emotional cues and their vulnerability to symptoms of anxiety.  相似文献   
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Group-living brown capuchins were given mirror-image stimulation as follows: (1) mirror 1 m away; (2) mirror attached to the cage-mesh; (3) angled mirrors creating a deflected image; (4) small mirror in the cage; and (5) small, transportable mirrors. The subjects were initially interested in the mirrors in each condition, but they generally habituated to them over the course of repeated presentations. Control (non-reflective) objects were attended to less than mirrors. Facial expressions occurred mostly in Condition 2, lateral and vertical head movements in Condition 3, reaching behind the mirror in Condition 2, looking obliquely into the mirror in Conditions 4 and 5. Despite these diverse conditions of exposure to mirrors, lasting for a total of over three months, no behaviours suggesting self-recognition were seen in the monkeys.  相似文献   
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ABSTRACT

Acerola fruits contain abundant ascorbic acid (AsA). The gene expression levels of three upstream enzymes in the primary AsA biosynthesis pathway were correlated with AsA contents in the fruits of two acerola cultivars. Multiple overexpression of the enzymes increased AsA contents, suggesting their high expression is important for high AsA accumulation in acerola fruits and the breeding of AsA-rich plants.

Abbreviations: AsA: ascorbic acid; PMI: phosphomannose isomerase; PMM: phosphomannomutase; GMP: GDP-d-mannose pyrophosphorylase; GME: GDP-d-mannose 3?,5?-epimerase; GGP: GDP-l-galactose phosphorylase; GPP: l-galactose-1-phosphate phosphatase; GDH: l-galactose dehydrogenase; GLDH: l-galactono-1,4-lactone dehydrogenase  相似文献   
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We investigated the behavior of primary rat hepatocytes in biochips using a microfluidic platform (the integrated dynamic cell culture microchip). We studied the effects of cell inoculation densities (0.2–0.5 × 106 cells/biochip) and perfusion flow rates (10, 25, and 40 µL/min) during 72 h of perfusion. No effects were observed on hepatocyte morphology, but the levels of mRNA and CYP1A2 activity were found to be dependent on the initial cell densities and flow rates. The dataset made it possible to extract a best estimated range of parameters in which the rat hepatocytes appeared the most functional in the biochips. Namely, at 0.25 × 106 inoculated cells cultivated at 25 µL/min for 72 h, we demonstrated better induction of the expression of all the genes analyzed in comparison with other cell densities and flow rates. More precisely, when primary rat hepatocytes were cultivated at these conditions, the time‐lapse analysis demonstrated an over expression of CYP3A1, CYP2B1, ABCC1b and ABCC2 in the biochips when compared to the postextraction levels. Furthermore, the AHR, CYP1A2, GSTA2, SULT1A1, and UGT1A6 levels remained higher than 50% of the postextraction values whereas values of HNF4α, CEBP, and PXR remained higher than 20% during the duration of the culture process. Nevertheless, an important reduction in mRNA levels was found for the xenosensors CAR and FXR, and the related CYP (CYP2E1, CYP7A1, CYP3A2, and CYP2D2). CYP1A2 functionality was illustrated by 700 ± 100 pmol/h/106 cells resorufin production. This study highlighted the functionality in optimized conditions of primary rat hepatocytes in parallelized microfluidic cultures and their potential for drug screening applications. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:401–410, 2014  相似文献   
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人眼房水动力学系统的建模与仿真方法研究   总被引:1,自引:0,他引:1  
为从宏观上应用工程方法进一步研究房水运行机理,提出了人眼前节房水流动系统的动力学仿真模型。依据目前眼科界较为公认的房水运行和眼压反馈机制建立系统构架,基于对眼科解剖学与生理学相关理论的分析、流体力学基本原理和临床参数进行系统辨识与参数确定。运用数字仿真的方法分剐在正常生理平稳状况和激发试验状况下对模型进行了仿真运行,获得了和临床结论较为一致的结果。能较好地模拟房水运行机制,在与临床可测量参数一致的同时能获得一些不易测量的参数,为研究房水动力学提供依据。  相似文献   
58.
卢慧  胡波  黄倩 《生物数学学报》2007,22(3):509-514
通过建立数学模型描述制作糖尿病大鼠模型的成本.针对成模率不确定导致的成本无法计算,本文通过分析成本支出项简化目标函数,使用血糖增加量代替以成模率表述的约束条件.简化后的成本模型可以直接计算,并能以此为基础在制作糖尿病大鼠模型时选择大鼠的体重和确定药物的注射剂量。  相似文献   
59.
为研究核基质结合区 (MAR)序列不同插入位置对转基因表达作用的影响,PCR扩增人β 珠蛋白MAR分别插入到含氯霉素乙酰转移酶(chloramphenicol acetyltransferase,CAT)报告基因真核表达载体pCATG表达盒两侧、5′端及3′端.酶切鉴定后,用阳离子聚合物转染CHO细胞,G418筛选出阳性细胞克隆,ELISA分析CAT基因的表达水平,半定量PCR分析CAT基因相对拷贝数.结果表明,表达盒两侧含MAR序列的载体能提高介导的转基因表达水平平均提高10.4倍,5′端含MAR序列的载体表达水平平均提高3.9倍,3′端含MAR序列的载体反而降低转基因表达水平.5′端含MAR序列的表达载体其转基因相对拷贝数高于其它两组载体的基因拷贝数,转基因表达量与基因拷贝数不成正比.  相似文献   
60.
Ten patients (five males and five females, 8–27 yearsof age) diagnosed cases of Usher's syndrome were tested fortheir gustative and olfactory functions. The tasting of thesemultiple handicapped patients was carried out by elicitationof innate reflex-like distinct facial expressions in responseto gustatory and nasal stimulation. Findings indicate normalgustatory and olfactory function as well as adequate hedonicresponses to presented stimuli. In view of the reported findingsit can be stated that Usher's syndrome affect selectively thesenses of vision, hearing and often also labyrinth, while tasteand smell functions are not affected.  相似文献   
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