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91.
不同喷施浓度及喷施次数对蕹菜产量及茎叶锌含量的影响结果表明:喷施0.05%及0.1%的硫酸锌液均能提高蕹菜的产量,但以0.05%的处理对产量的提高作用最明显,浓度超过0.1%时,对蕹菜生长有抑制作用提高喷锌浓度,蕹菜锌含量的增加为叶片大于茎;喷施1~2次,有明显的增产效果,喷施超过2次反而减产;随着喷施次数的增加,蕹菜锌含量也增加。  相似文献   
92.
AIM To study whether C1q/tumor necrosis factor (TNF)-related protein 3 (CTRP3)protect vascular endothelium in rats with hyperuricemia and its potential mechanisms. METHODS An animal model of hyperuricemia was established by using male SD rats drinking 10% fructose water (n=10). The rats drinking normal water served as normal controls (n=10). After 12 weeks, the rats were given a single injection with Ad-CTRP3 or Ad-GFP. The experiment was ended at 14th day after transfection.The serum levels of uric acid and nitric oxide (NO) were evaluated. The serum contents of TNF-α and interleukin-6 (IL-6) were measured by ELISA. HE staining and TUNEL assay were used to assess the morphological changes of intima and apoptosis of endothelial cells in thoracic aorta, respectively. The mRNA levels of endothelial nitric oxide synthase (eNOS), TNF-α and IL-6 were detected by RT-qPCR. The protein levels of CTRP3 and Toll-like receptor 4 (TLR4) were determined by Western blot. RESULTS Compared with normal control group, the rats with hyperuricemia showed lower CTRP3 and higher TLR4 protein levels in the thoracic aorta (P<0.05). Hyperuricemic rats had higher serum contents of uric acid, TNF-α and IL-6 (P<0.05). Also, the intima structure disturbance of thoracic aorta, increased apoptotic rate, higher mRNA levels of TNF-α and IL-6 as well as lower mRNA levels of eNOS were observed (P<0.05). By contrast, CTRP3 over-expression decreased TLR4 protein levels, reduced inflammatory cytokines, and obviously improved the morphology and function of thoracic aorta in the rats with hyperuricemia. CONCLUSION CTRP3 protect vascular endothelium in rats with hyperuricemia maybe via down-regulation of TLR4- mediated inflammatory signaling pathway.  相似文献   
93.
辣椒新品种辣优4号的选育   总被引:2,自引:0,他引:2  
辣优 4号是以湖南地方品种分离株Ⅱ经多代自交筛选纯化的优良自交系 33号椒为母本、以材料h7 1经多代单株自交筛选的优良自交系 30号椒为父本配制而成的辣味型一代杂种 ,熟性早 ,前期产量比对照品种湘研 1号增产 16 .5%~ 4 9.1%。一般产量 16 0 0~ 2 80 0kg·(6 6 7m2 ) - 1。田间表现抗疫病、青枯病和病毒病。结果性好 ,单果质量 35~ 50g ,果实长牛角形 ,果表面光滑 ,色绿 ,商品率高 ,品质优良。现已在广东、广西、江西、海南、湖南等地推广种植 ,面积达80 0hm2 。  相似文献   
94.
【目的】为探讨水稻幼苗根系NH_4~+、K~+吸收的交互作用,深化水稻养分吸收理论,【方法】采用溶液培养的方法,对低钾及高钾浓度下水稻在有铵和无铵时的K~+吸收动力学特征进行了研究,对不同钾浓度下水稻根系NH_4~+的吸收速率进行了比较。【结果】1)当K~+0.2 mmol/L时,水稻根系通过高亲和转运系统吸收K~+服从Michaelich-Menten动力学方程;NH_4~+的存在显著降低K~+的最大吸收速率(Vmax),且降幅随着NH_4~+浓度的增加而增大;NH_4~+对水稻根表载体与K~+的亲和力(Km)影响较小,在1.62 mmol/L NH_4~+浓度下,水稻品种齐粒丝苗和沪科3号的Km分别下降了12.33%和16.46%,远低于Vmax 47.30%和39.21%的降幅。2)当K~+0.5 mmol/L时,水稻根系K~+低亲和转运系统发挥作用,K~+吸收速率随浓度的增加而不断增加,呈不饱和特征;但在相同K~+浓度下,水稻根系的K~+吸收速率随NH_4~+浓度的增加而下降。3)水稻根系对NH_4~+的吸收速率随着NH_4~+浓度的增加而增加;在相同NH_4~+浓度下,水稻根系对NH_4~+的吸收速率受K~+浓度的影响很小。【结论】NH_4~+抑制水稻苗期根系K~+的高亲和转运和低亲和转运,NH_4~+对K~+高亲和吸收的影响主要是由于铵竞争细胞膜上的钾载体所致;外界K~+浓度的变化对水稻幼苗的NH_4~+吸收速率影响很小。水稻铵钾的交互作用主要表现在NH_4~+对K~+吸收的抑制作用。  相似文献   
95.
水通道蛋白不仅控制着水分和一些小分子溶质的跨膜运输,也是植物体应对非生物胁迫的重要组成部分。为了进一步研究小麦水通道蛋白的功能,本研究以NCBI和Ensemble Plant数据库中查找出的已报道的小麦水通道蛋白基因序列为模板,针对其保守区设计了19对引物,应用PCR的方法从5个小麦品种中克隆出19个基因片段。通过比对鉴定到一个此前未曾报道的新基因,并对其进行生物信息学分析,将其命名为TaNIP4-1。理化特性分析表明,该基因位于3A染色体短臂,基因全长1 315bp,CDS序列长度864bp,含有3个外显子和2个内含子,编码含有288个氨基酸的多肽,含有保守的沙漏模型,有6个跨膜区和2个保守的NPA基序。亚细胞定位预测结果表明该基因位于质膜上。该基因启动子序列含有与逆境响应相关的顺式调控元件,而对7日龄的麦苗进行干旱和盐胁迫处理后,其qRT-PCR结果显示,干旱和盐处理5h后,TaNIP4-1基因在小麦叶片中的表达量明显上调;盐处理7d后,TaNIP4-1基因在小麦根部的表达量显著上调。由此可见,TaNIP4-1基因参与了小麦应对逆境的过程。  相似文献   
96.
97.
AIM: To investigate whether Toll-like receptor 4 (TLR4) and Nod-like receptor protein 3 (NLRP3) inflammasome were involved in contrast medium (CM)-induced inflammation and injury in renal tubular epithelial cells. METHODS: Iopromide was used to injure NRK-52E cells in the study. The cell viability was measured by CCK-8 assay. The protein levels of TLR4, NLRP3, apoptosis-associated speckle-like protein (ASC), caspase-1 and cleaved caspase-3 were determined by Western blot. The releases of interleukin (IL)-1β and IL-18 were detected by ELISA. The apoptotic rate was evaluated by Hoechst staining, and mitochondrial membrane potential (MMP) was analyzed by JC-1 staining. siRNA was transfected into the NRK-52E cells to silence NLRP3 expression. RESULTS: CM decreased the viability of NRK-52E cells (P<0.05). CM also elevated the protein levels of cleaved caspase-3, TLR4, NLRP3, IL-1β and IL-18 (P<0.05). Silencing NLRP3 attenuated CM-induced releases of inflammatory cytokines. Moreover, treatment with TLR4 inhibitor TAK-242 or knockdown of NLRP3 by siRNA transfection both attenuated cell apoptosis and loss of MMP caused by CM. CONCLUSION: TLR4/NLRP3 inflammasome takes part in the pathogenesis of CM-induced acute kidney injury, and mediates CM-induced injury and inflammation in renal tubular epithelial cells.  相似文献   
98.
AIM: To detect the expression of miRNA-363 and SOX4 in osteosarcoma tissues and to investigate the effect of miRNA-363 on the viability and apoptosis of human osteosarcoma cell line MG-63.METHODS: Real-time PCR was used to detect the expression level and the relationship of miRNA-363 and SOX4 mRNA in the osteosarcoma tissues and the corresponding paratumorous tissues collected from 63 patients. The expression levels of miRNA-363 and SOX4 in osteosarcoma cell line MG-63 after transfected with miRNA-363 mimics were measured. The cell viability was measured by CCK-8 assay. Flow cytometry was used to monitor the changes of cell cycle and apoptosis. The changes of SOX4 and miRNA-363 expression levels in the MG-63 cells after transfection with SOX4 siRNA or pcDNA/SOX4 was detect by real-time PCR.RESULTS: The expressed level of miRNA-363 was lower, and the expression level of SOX4 was higher in the osteosarcoma tissues than those in the adjacent normal tissues. A significantly negative correlation between the expression levels of miRNA-363 and SOX4 was observed. The expression of miRNA-363 in the MG-63 cells after transfection with miRNA-363 mimics was significantly up-regulated, while the expression of SOX4 in the MG-63 cells was significantly down-regulated, with significant difference as compared with the cells transfected with miRNA-NC and control cells. The viability of MG-63 cells was inhibited, the cell cycle was arrested in G0/G1 phase, and the cell apoptosis was increased by transfection with miRNA-363 mimics. The relative protein expression levels of SOX4 in SOX4 siRNA group and pcNDA/SOX4 group were significantly different from those in negative control group, but the relative expression levels of miRNA-363 had no significant difference. Over-expression of SOX4 restored the viability of the MG-63 cells reduced by miR-363.CONCLUSION: The expression level of miRNA-363 is low in human osteosarcoma tissue. miRNA-363 may inhibits the viability of osteosarcoma cell line MG-63 and promotes cell apoptosis in vitro via inhibiting the SOX4 expression.  相似文献   
99.
基于CuFe2O4纳米粒子能显著增强Luminol-EDTA体系的发光,首次建立了Luminol-EDTA-CuFe2O4 NPs化学发光新体系。紫外吸收光谱和化学发光光谱表明纳米CuFe2O4注入Luminol-EDTA体系后,未生成新发光物质,结合纳米CuFe2O4的特性,提出了CuFe2O4 NPs参与Luminol-EDTA体系可能的发光机理。研究发现芦丁能抑制Luminol-EDTA-CuFe2O4 NPs体系的化学发光,结合流动注射技术,将此化学发光体系应用于芦丁片中芦丁含量的测定。在优化实验条件下,芦丁浓度在2×10-8~2×10-5 mol/L范围内芦丁浓度的对数和相对化学发光值呈线性,芦丁浓度检出限(LOD)为1.21×10-9 mol/L。将本方法应用于芦丁片中的芦丁含量测定,回收率为97%~102%,RSD为2.54%(c=1×10-7mol/L,n=11)。  相似文献   
100.
以GA_4处理的果梅休眠芽和转PmRGL2基因杨树叶片为材料,通过测定H_2O_2含量、抗氧化酶类活性及其编码基因和信号转导相关基因表达的变化,分析了H_2O_2在外源GA_4解除果梅休眠中的信号作用。结果表明:GA_4处理的果梅花芽的萌芽率显著高于对照,且H_2O_2含量在休眠解除时达到峰值,信号转导相关基因表达发生规律性变化;‘桃形梅’和‘丰后’的需冷量分别为574 CH(低温小时数Chilling hours)和1 108 CH,休眠解除前后,两品种叶芽中的H_2O_2含量没有显著差异,但需冷量低的‘桃形梅’具有更高的抗氧化酶类活性;转Pm RGL2杨树中NADPHoxi下调表达,有利于使H_2O_2含量维持在较低水平,并对赤霉素合成及信号转导相关基因的表达产生影响,而抗氧化酶类活性及其编码基因的表达量上升。推测GA_4通过调控抗氧化酶类活性而影响H_2O_2含量的变化,并引起上下游多种信号相关基因表达水平的变化,最终对休眠解除起作用。  相似文献   
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