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91.
It is well known that an increase of and better grain can be obtained by the application of an adequate amount of quick-acting nitrogen fertilizers such as ammonium sulphate, thirty to twenty five days before heading, and this is a common practice of top-dressing, being called “Hogoe” in Japanese. It is also well known that excess of nitrogen supplied at this time makes plants weak against mechanical injury, insects and disease. For the application of “Hogoe”, therefore, an accurate diagnosis of the nitrogen nutrient condition of rice is required. In a series of investigations on the nitrogen metabolism, the author found that asparagine appeared in parallel with the increase of nitrogen concentration in rice plants, and considered that the detection of asparagine would be a good indicator for assessing the nitrogen requirement of rice lantstl).  相似文献   
92.
AIM:To investigate the roles of p21-activated kinase 6 (PAK6) and its target miRNA on the migratory and invasive abilities of non-small cell lung cancer cells. METHODS:miRNA candidates targeting PAK6 were predicted by a target prediction program. The expression of PAK6 was measured by real-time PCR and Western blotting after A549 cells were transfected with miR-23a mimics or inhibitory oligonucleotides. Luciferase reporter assay was used to determine whether PAK6 was the direct target of miR-23a. The abilities of cell migration and invasion were detected by Matrigel invasion assay and Transwell migration assay. The expression of PAK6 and matrix metalloproteinase 9 (MMP-9) was analyzed by Western blotting after A549 cells were transfected with siPAK6 or miR-23a mimics. RESULTS:miR-23a was identified by a target prediction program. Exogenetic over-expression of miR-23a resulted in a remarkable decrease in PAK6 expression (69%), whereas miR-23a inhibitory oligonucleotides induced pronounced increase in PAK6 expression (52%). The luciferase activity was significantly inhibited by 52% in wild-type PAK6 group, while there was no significant difference in the mutation group. The mRNA level of PAK6 had no change as detected by real-time PCR. Matrigel invasion assay and Transwell migration assay demonstrated there exogenetic over-expression of miR-23a markedly reduced the migration and invasion of PC-3 cells (73% and 59%, respectively). The MMP-9 expression remarkably decreased by 85% and 76% in the A549 cells transfected with siPAK6 and miR-23a mimics, respectively. CONCLUSION:miR-23a inhibits the migration and invasion of non-small cell lung cancer cells by repressing PAK6-MMP-9 signaling pathway.  相似文献   
93.
在室养条件下观察了MS-222、苯佐卡因和乌拉坦对稀有鮈鲫(Gobiocypris rarus)的麻醉效果。结果表明,乌拉坦不宜作为稀有鮈鲫的麻醉剂,而一定浓度的MS-222或苯佐卡因可导致稀有鮈鲫的快速麻醉;不同麻醉剂浓度、不同的作用时间下,稀有鮈鲫在行为上呈现不同的反应,据此可分为轻度镇静、深度镇静、轻度麻醉、中度麻醉、深度麻醉和髓质麻醉阶段;根据反应时间、恢复时间、维持时间和存活率等,建议使用60mg/L的苯佐卡因或100~110mg/L的MS-222作为深度麻醉剂量。  相似文献   
94.
合成了一种命名为多孔配位网络结构222(PCN 222)的金属有机骨架化合物(MOFs),并将其用作农药残留检测中酶抑制法的新型增敏剂。对所制备的PCN 222微观形态、结构、X射线衍射(XRD)和热稳定性进行了系统表征。证明该MOFs是一种多孔的棒状结构(棒状结构主轴为六面体),并具有大的表面积和强的热稳定性。基于PCN 222的性能,在有机磷农药快检中添加PCN 222材料,增强了传统酶抑制法的灵敏性。为进一步研究,将毒死蜱选为模型分析物,在最佳条件下,吸光度变化量提高了68.8%(3 min内)。此外,该方法具有简单、快速、成本低的优点,为复杂样品基质中有机磷农药的测定提供了一种实用工具。  相似文献   
95.
AIM To study the role and regulatory mechanism of microRNA-433 (miR-433) in fibrosis. METHODS TargetScan was used to predict the potential target genes of miR-433. The changes of miR-433 expression were detected after transforming growth factor β1 (TGF-β1) treatment of mouse embryonic fibroblasts (NIH-3T3 cells) for 24 h. The effects of miR-433 mimic on the expression of p-SMAD2, fibronectin (FN), α-smooth muscle actin (α-SMA) and connective tissue growth factor (CTGF) in TGF-β1 treated cells were examined. The effects of miR-433 mimic transfection on the viability and S-phase fraction of NIH-3T3 cells induced by TGF-β1 were detected by CCK-8 assay and flow cytometry. A model of silica-induced pulmonary fibrosis in mice was established, and agomiR-433 was used for intervention. HE staining and Masson staining were used to observe the effect of miR-433 on pulmonary fibrosis in the mice. The expression of α-SMA in lung tissues was detected by immunohistochemistry. RESULTS miR-433 specifically bound to the 3'-UTR of SMAD2 and inhibited its expression at protein and mRNA levels. TGF-β1 down-regulated the expression of miR-433 in NIH-3T3 cells, up-regulated the protein level of p-SMAD2 and the expression of FN, α-SMA and CTGF at protein and mRNA levels, and increased the viability and the number of S-phase cells. miR-433 mimic reversed the effects of TGF-β1 on NIH-3T3 cell viability and S-phase arrest. In a model of silica-induced pulmonary fibrosis in mice, agomiR-433 inhibited the progress of pulmonary fibrosis and reduced the expression of α-SMA in mouse lung tissues. CONCLUSION miR-433 may interfere with TGF-β1/SMAD2 signaling pathway through targeting SMAD2, thus participating in the regulation of fibrosis process.  相似文献   
96.
AIM To investigate the effect of sinomenine (SIN) on the apoptosis of human rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS) and its molecular mechanism. METHODS Human RA FLS were isolated and cultured. The cells treated with lipopolysaccharide (LPS) at 100 mg/L was recorded as LPS group. The cells treated with SIN at 3.2 mmol/L and LPS at 100 mg/L were recorded as LPS+SIN group. The cells without any treatment served as blank group. The cells transfected with miR-con, miR-23b-3p, si-con and si-fibroblast growth factor 9 (FGF9) and treated with 100 mg/L LPS were recorded as LPS+miR-con group, LPS+miR-23b-3p group, LPS+si-con group and LPS+si-FGF9 group, respectively. The anti-miR-con, anti-miR-23b-3p, pcDNA and pcDNA-FGF9 were also transfected into RA FLS, and then the cells were treated with SIN at 3.2 mmol/L and LPS at 100 μg/mL. These cells were recorded as LPS+SIN+anti-miR-con group, LPS+SIN+anti-miR-23b-3p group, LPS+SIN+pcDNA group, LPS+SIN+pcDNA-FGF9 group, respectively. The cell viability was measured by CCK-8 assay. The number of colonies was accessed by colony formation experiment. The protein levels of FGF9, cleaved caspase-3, Bax and Bcl-2 were determined by Western blot. The apoptosis was analyzed by flow cytometry. The expression of miR-23b-3p and FGF9 mRNA was detected by RT-qPCR. Dual-luciferase reporter assay was used to verify the targeting relationship between miR-23b-3p and FGF9. RESULTS Treatment with SIN promoted LPS-induced apoptosis of RA FLS, inhibited cell proliferation, up-regulated miR-23b-3p expression, and down-regulated FGF9 expression. miR-23b-3p targeted FGF9. Over-expression of miR-23b-3p or silencing of FGF9 inhibited LPS-induced proliferation and enhanced apoptosis of the RA FLS. Interfering with miR-23b-3p or over-expression of FGF9 reversed the effects of SIN on the proliferation and apoptosis of LPS-induced RA FLS. CONCLUSION Sinomenine induces RA FLS apoptosis and inhibits cell proliferation through miR-23b-3p/FGF9 signaling.  相似文献   
97.
AIM: To investigate the expression of microRNA (miRNA)-93 in acute lymphocytic leukemia (ALL) and its effect on the proliferation of acute T-cell leukemia Jurkat cells.METHODS: The expression of miRNA-93 in the bone marrow samples of patients with ALL was measured by real-time PCR. After down-regulation of miRNA-93 by transfection with miRNA-93 inhibitor in the Jurkat cells, the cell viability, cell proliferation and cell cycle distribution were detected by CCK-8 assay, EdU assay and flow cytometry, respectively. Furthermore, the protein levels of cell cycle-related molecules such as cyclin D1, cyclin-dependent kinase 4 (CDK4), phosphorylation retinoblastoma (Rb) and P27 were measured by Western blot.RESULTS: miRNA-93 was highly expressed in the patients with ALL, and the expression level was highest in the high risk patients. Down-regulation of miRNA-93 inhibited Jurkat cell viability, arrested cell cycle in G1/S transition. In addition, the protein levels of cyclin D1, CDK4 and p-Rb were significantly decreased, the protein expression of P27 was increased in Jurkat cells trasfected with miRNA-93 inhibitor.CONCLUSION: miRNA-93 expression is increased in ALL patients. Down-regulation of miRNA-93 restrains cell proliferation in the acute T cell leukemia cell line Jurkat via regulating cell cycle-related molecules.  相似文献   
98.
99.
AIM: To study the expression of microRNA (miRNA)-181a in different human lung adenocarcinoma cell lines, and to investigate the effect of miRNA-181a on cell function and its mechanism in human lung adenocarcinoma drug resistant cell A549/DDP. METHODS: Real-time PCR was used to detect the expression of miRNA-181a in BEAS-2B cells, A549 cells and A549/DDP cells. The A549/DDP cells were transfected with pGenesil-miRNA-181a eukaryotic expression plasmid. At the same time, the untransfection group and negative transfection group were also set up. The expression of miRNA-181a, cell viability, cell growth inhibition and apoptosis rate during cis-diamminedichloroplatinum (DDP) treatment, cell cycle, cell invasion, the protein expression of miRNA-181a target genes bcl-2 and p53 in the A549/DDP cells were determined by real-time fluorescence quantitative PCR, MTT assay, flow cytometry, Transwell method and Western blot, respectivly. RESULTS: The expression of miRNA-181a in A549 cells and A549/DDP cells was significantly lower than that in BEAS-2B cells, and the lowest expression level was observed in A549/DDP cells (P<0.05). The expression of miRNA-181a in A549/DDP cells was significantly increased after transfection with pGenesil-miRNA-181a (P<0.05). The cell viability, cell cycle and invasion ability of the A549/DDP cells were inhibited after miRNA-181a transfection (P<0.05). The cell growth inhibition rate and apoptotic rate of the A549/DDP cells were increased (P<0.05). The expression of Bcl-2 was reduced, but the expression of P53 was increased after transfection with miRNA-181a in A549/DDP cells (P<0.05). CONCLUSION: miRNA-181a may be correlated with the development of human lung adenocarcinoma. miRNA-181a can serve as a new target for treatment of lung cancer.  相似文献   
100.
AIM: To investigate the expression of microRNA-375 (miR-375) in hepatocellular carcinoma (HCC) and to analyze the target genes and signaling pathways regulated by miR-375. METHODS: The expression of miR-375 was examined at tissue microarray of HCC by in situ hybridization. The whole human genome chip and bioinformatics analysis were applied to screen out the differential expression genes and signaling pathways in 4 HCC cell lines transfected with miR-375 mimic. RESULTS: In situ hybridization showed the expression of miR-375 in HCC tissues were obviously higher than that in tumor-adjacent tissues (P < 0.05). There were 20 co-upregulated genes and 17 co-downregulated genes in all 4 cell lines. Bioinformatic analysis showed that there were 54 signaling pathways related to up-regulated genes and 48 signaling pathways related to down-regulated genes in all 4 cell lines. CONCLUSION: miR-375 may play a key role in the pathological process of HCC. The bioinformatic analysis is able to screen the target genes and signaling pathways regulated by miR-375 and to provide an explicit direction for further mechanism research on HCC.  相似文献   
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