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51.
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通过土培试验,研究了土壤水分和供硼状况对不同硼效率油菜苗期生长、叶片水分含量和硼形态的影响.结果表明:低水分胁迫条件下,硼高效甘蓝品种和硼低效甘蓝品种在高供硼水平下的单株鲜质量比低供硼水平分别增加了43.1%和31.7%,但品种间没有显著差异;硼高效品种在两种供硼水平下的束缚态水分含量分别比低效品种高11.4%和1.7%,半束缚态硼分配比例分别比低效品种高6.9%和23.8%.正常水分条件下,硼高效甘蓝品种和硼低效甘蓝品种在高供硼水平下的单株鲜质量比低供硼水平分别增加了11.1%和27.4%;硼高效品种在两种供硼水平下的自由态水分含量较硼低效品种多,自由态硼累积量为低效品种的2倍多,这有利于硼在高效植物体内的移动运输. 相似文献
53.
Chen Zhong Xin-Hua Liu Jun Chang Jian-Ming Yu Xun Sun 《Bioorganic & medicinal chemistry letters》2013,23(15):4413-4418
Four types of resveratrol dimerized analogues were synthesized and evaluated in vitro on LPS-induced NO production in RAW 264.7 cells. The results showed that several compounds, especially those containing 1,2-diphenyl-2,3-dihydro-1H-indene core (type I), exhibited good inhibitory activities. Among 25 analogues, 12b showed a significant inhibitory activity (49% NO production at 10 μM, IC50 = 3.38 μM). Further study revealed that compound 12b could suppress LPS-induced iNOS expression, NO production, and IL-1β release in a concentration-dependently manner. The mechanism of action (MOA) involved for its anti-inflammatory responses was through signaling pathways of p38 MAPK and JNK1/2, but not ERK1/2. 相似文献
54.
Xun Liu Yanni Wang Cheng Wang Chenggang Shi Cailian Cheng Jinxia Chen Huijuan Ma Linsheng Lv Lin Li Tanqi Lou 《PloS one》2013,8(11)
Background
We sought to develop a new equation to estimate glomerular filtration rate (GFR) in Chinese elderly population.Methods
A total of 668 Chinese elderly participants, including the development cohort (n = 433), the validation cohort (n = 235) were enrolled. The new equation using the generalized additive model, and age, gender, serum creatinine as predictor variables was developed and the performances was compared with the CKD-EPI equation.Results
In the validation data set, both bias and precision were improved with the new equation, as compared with the CKD-EPI equation (median difference, −1.5 ml/min/1.73 m2 vs. 7.4 ml/min/1.73 m2 for the new equation and the CKD-EPI equation, [P<0.001]; interquartile range [IQR] for the difference, 16.2 ml/min/1.73 m2 vs. 19.0 ml/min/1.73 m2 [P<0.001]), as were accuracies (15% accuracy, 40.4% vs. 30.6% [P = 0.02]; 30% accuracy, 71.1% vs. 47.2%, [P<0.001]; 50% accuracy, 90.2% vs. 75.7%, [P<0.001]), allowing improvement in GFR categorization (GFR category misclassification rate, 37.4% vs. 53.2% [P = <0.001]).Conclusions
A new equation was developed in Chinese elderly population. In the validation data set, the new equation performed better than the original CKD-EPI equation. The new equation needs further external validations. Calibration of the GFR referent standard to a more accurate one should be an useful way to improve the performance of GFR estimating equations. 相似文献55.
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本研究探讨利用荧光定量PCR技术评价Sindbis病毒经亚甲蓝光化学处理后灭活效果的可行性。研究采用不同光照强度对Sindbis病毒进行亚甲蓝光化学灭活处理,并用SYBR Green I荧光定量PCR对Sindbis病毒的cDNA进行扩增,同时以细胞病变法做平行对照以测定病毒残余滴度。结果显示在亚甲蓝光化学处理过程中,随着光照强度的增强,病毒残余滴度由6.50 LgTCID50/mL逐渐降低至检测限以下,同时病毒核酸的拷贝数显著下降(P<0.05),并与病毒感染性的降低呈线性相关(R2>0.98)。以上结果表明,亚甲蓝光化学灭活法对Sindbis病毒核酸有破坏作用,病毒核酸损伤程度随光照强度的增强而增加,且与病毒感染性的降低存在相关性,提示荧光定量PCR技术评价亚甲蓝光化学法的病毒灭活效果具有可行性。 相似文献
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Parental Monitoring,Parent-Adolescent Communication,and Adolescents’ Trust in Their Parents in China
Purpose
Trust is an important aspect of interpersonal relationships, but little is known about adolescents’ interpersonal trust. The aim of the present study was to examine the associations among parental monitoring, parent-adolescent communication, and adolescents’ trust in their parents in China.Methods
Data in this study were collected as part of the cross-sectional study of children in China. 3349 adolescents (female 48.6%, age range of 12–15 years) were randomly selected from 35 secondary schools in April, 2009 and administered to the Adolescent Interpersonal Trust Scale, the Parental Monitoring Scale, and the Parent-Adolescent Communication Scale.Results
Adolescents’ trust in their parents was positively related to parental monitoring and parent-adolescent communication. Furthermore, parent-adolescent communication mediated the association between parental monitoring and adolescents’ trust in their parents. The mediation model fit data of both genders and three age groups equally well.Conclusions
Parental monitoring and parent-adolescent communication play an importance role in fostering adolescents’ trust in their parents. 相似文献60.
Regulation of autophagy protects against liver injury in liver surgery-induced ischaemia/reperfusion
Chenxia Hu Lingfei Zhao Fen Zhang Lanjuan Li 《Journal of cellular and molecular medicine》2021,25(21):9905-9917
Transient ischaemia and reperfusion in liver tissue induce hepatic ischaemia/reperfusion (I/R) tissue injury and a profound inflammatory response in vivo. Hepatic I/R can be classified into warm I/R and cold I/R and is characterized by three main types of cell death, apoptosis, necrosis and autophagy, in rodents or patients following I/R. Warm I/R is observed in patients or animal models undergoing liver resection, haemorrhagic shock, trauma, cardiac arrest or hepatic sinusoidal obstruction syndrome when vascular occlusion inhibits normal blood perfusion in liver tissue. Cold I/R is a condition that affects only patients who have undergone liver transplantation (LT) and is caused by donated liver graft preservation in a hypothermic environment prior to entering a warm reperfusion phase. Under stress conditions, autophagy plays a critical role in promoting cell survival and maintaining liver homeostasis by generating new adenosine triphosphate (ATP) and organelle components after the degradation of macromolecules and organelles in liver tissue. This role of autophagy may contribute to the protection of hepatic I/R-induced liver injury; however, a considerable amount of evidence has shown that autophagy inhibition also protects against hepatic I/R injury by inhibiting autophagic cell death under specific circumstances. In this review, we comprehensively discuss current strategies and underlying mechanisms of autophagy regulation that alleviates I/R injury after liver resection and LT. Directed autophagy regulation can maintain liver homeostasis and improve liver function in individuals undergoing warm or cold I/R. In this way, autophagy regulation can contribute to improving the prognosis of patients undergoing liver resection or LT. 相似文献