简介:Thereisagrowingsupportforthelowlyingscalarmesonsf0(500),f0(980),a0(980),and(800)tobegenerateddynamicallyfromtheinteractionofpseudoscalarmesons,whilethecaseofthenextsetofscalarresonancesathigherenergies,f0(1370),f0(1710),K0(1430)ismoreaquestionofdebate.Soisthecaseofthetensorresonancesf2(1270),f′2(1525),K2(1430).AnewperspectiveonthesestateshasbeenofferedinRef.[1]wherethef0(1370)andf2(1270)resonancesareshowntobegeneratedfromtheinteractionprovidedbythelocalhiddengaugeLagrangiansimplementingunitarization.Itisshownthattheideaofthenatureofthesestatesasvectormeson-vectormesoncompositestateshasbeentestedinmanyreactions.Yet,thepermanentdiscussionoftheissuedemandsextrachecksforotherobservablesand,inthissense,theweakdecaysbringanewsourceofvaluableinformationthatshouldservetotestdifferentmodels.
简介:甘薯(Ipomoeabatatas(L.)Lam.)作为世界上一种重要的粮食、饲料、工业原料及新型能源作物,从有性生殖F1选择优良实生系进行选择育种一直是甘薯育种的重要方式。为了优化甘薯杂交育种方法,合理选配杂交组合,提高育种效率,本试验利用SSR标记研究了甘薯杂交群体基于SSR标记及13个农艺性状的遗传多样性,得到了群体内的聚类图,并且筛选出了甘薯的高产株系。群体SSR标记的聚类分析结果显示,群体材料与各亲本遗传距离比较远,被聚为3类,而亲本单独聚在另外一类。13个农艺性状的聚类将亲本与部分群体材料聚在了一起,且将群体材料和亲本材料作为一个整体时,其遗传距离的变异高达30%以上,远远高于SSR标记所获得的遗传变异系数。
简介:目的探索不同f2/f1比值对DPOAEs幅值的影响,寻找最佳的测试参数,以得到最大的DPOAEs测值.方法对12例(24耳)正常青年人进行不同f2/f1比值条件下的DPOAEs幅值测试.结果当f1/f1=1.220时,DPOAEs幅值最大(P<0.05或P<0.01).当f2/f1=1.232时,除了f2=2002Hz处以外,其DPOAEs幅值与f2/f1=1.220时无显著性差异(P>0.05).其他f2/f1值的DPOAEs幅值均较低,多数测值与f2/f1=1.220时相比均有显著性差异(P<0.05或P<0.01).结论f2/f1=1.220~1.232时,DPOAEs测值最大,此范围为最佳测试参数值.
简介:AbstractBackground:Pancreatic stellate cells (PSCs) activation plays a critical role in the development of chronic pancreatitis. Previous studies confirmed that thromboxane A2 receptor (TxA2r) was overexpressed in activated PSCs in rats. The purpose of this study was to investigate the role of TxA2r in the activation of PSCs induced by 8-epi-prostaglandin F2α (8-epi-PGF2α).Methods:TxA2r expression in both quiescent and activated PSCs was detected by immunocytochemistry and immunoblot assay. Isolated PSCs were treated with 8-epi-PGF2α (10-6, 10-7, 10-8 mol/L) for 48 h, and SQ29548 (10-4, 10-6, and 10-7 mol/L), a TxA2r-specific antagonist, for 48 h, respectively, to identify the drug concentration with the best biological effect and the least cytotoxicity. Then isolated PSCs were treated with SQ29548 (10-4 mol/L) for 2 h, followed by 10-7 mol/L 8-epi-PGF2α for 48 h. Real-time polymerase chain reaction was performed to detect the messenger RNA (mRNA) levels of α-smooth muscle actin (α-SMA) and collagen I. Comparisons between the groups were performed using Student’s t test.Results:TxA2r was up-regulated in activated PSCs in vitro compared with quiescent PSCs (all P < 0.001). Compared with the control group, different concentrations of 8-epi-PGF2a significantly increased mRNA levels of α-SMA (10-6 mol/L: 2.23 ± 0.18 vs. 1.00 ± 0.07, t= 10.70, P < 0.001; 10-7 mol/L: 2.91 ± 0.29 vs. 1.01 ± 0.08, t= 10.83, P <0.001; 10-8 mol/L, 1.67 ± 0.07 vs. 1.00 ± 0.08, t= 11.40, P < 0.001) and collagen I (10-6 mol/L: 2.68 ± 0.09 vs. 1.00 ± 0.07, t = 24.94, P < 0.001; 10-7 mol/L: 2.12 ± 0.29 vs. 1.01 ± 0.12, t = 6.08, P < 0.001; 10-8 mol/L: 1.46 ± 0.15 vs. 1.00 ± 0.05, t = 4.93, P = 0.008). However, different concentrations of SQ29548 all significantly reduced the expression of collagen I (10-4 mol/L: 0.55 ± 0.07 vs. 1.00 ± 0.07, t = 10.47, P < 0.001; 10-6 mol/L: 0.56 ± 0.10 vs. 1.00 ± 0.07, t = 6.185, P < 0.001; 10-7 mol/L: 0.27 ± 0.04 vs. 1.00 ± 0.07, t= 15.41, P < 0.001) and α-SMA (10-4 mol/L: 0.06 ± 0.01 vs. 1.00 ± 0.11, t= 15.17, P < 0.001; 10-6 mol/L: 0.28 ± 0.03 vs. 1.00 ± 0.11, t= 11.29, P < 0.001; 10-7 mol/L: 0.14 ± 0.04 vs. 1.00 ± 0.11, t= 12.86, P < 0.001). After being treated with SQ29548 (10-4 mol/L) and then 8-epi-PGF2α (10-7 mol/L), the mRNA levels of a-SMA (0.20 ± 0.08 vs. 1.00 ± 0.00, t= 17.46, P < 0.001) and collagen I (0.69 ± 0.13 vs. 1.00 ± 0.00, t = 4.20, P = 0.014) in PSCs were significantly lower than those of the control group.Conclusions:The results show that 8-epi-PGF2α promoted PSCs activation, while SQ29548 inhibited PSCs activation induced by 8-epi-PGF2α. The result indicated that TxA2r plays an important role during PSC activation and collagen synthesis induced by 8-epi-PGF2αin vitro. This receptor may provide a potential target for more effective antioxidant therapy for pancreatic fibrosis.
简介:摘要本文以一实际工程为例,对超高层剪力墙结构设计计算中的若干关键技术问题进行介绍,如结构选型、结构分析及抗震加强措施等内容。本文有关计算方法可为相关工程设计参考。
简介:摘要:如何保证隧道在富水区穿越断裂带地质条件下的安全施工是隧道施工的关键,本文结合工程实例,针对富水隧道在穿越F2断裂带且岩体为松散角砾岩地质条件下,详细介绍断裂带松散角砾岩隧道超前支护及初期支护措施,主要包含采用超前小导管、超前大管棚、水泥-水玻璃双浆液注浆、初期支护等通过断裂带塌方体的安全施工技术,技术实施后到达预期效果,对类似工程有较高的参考价值。