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121.
木粒--SPDA是我们根据木腐生性食用菌在自然状态下,均发生于树木上的特性,以及食用菌在营养需求上与其习性相关的原理,在SPDA基础上添加适量的木粒制成的一种母种培养基.在我们多年的使用中发现,用该培养基培养的母种生长势好,在转接原种时,适应能力强,萌发定植快;用作菌种保藏基质时,保藏时间长,且能很好保持菌种的优良性状.  相似文献   
122.
AIM: To investigate whether leukotriene D4(LTD4) would stimulates proliferation of cultured human airway smooth muscle (ASMC). METHOD: Human ASMC were isolated and subcultured, varying concentration of LTD4 were added to the media. Cell counts were obtained, -thymidine([3H]-TdR) incorporation and inositol 1, 4, 5-trisphosphate (IP3) accumulation were measured. RESULTS: LTD4(0.1nmol·L-1~10 nmol·L-1) increased cell number and also increased incorporation of[3H]-TdR and accumulation of IP3 in a concentration dependent manner(P<0.01). The latter response was blocked by phospholipase C inhibition with neomycin (1 μmoL·L-1(P<0.01). However, neomycin had no effect on the promitogenic action of LTD4. CONCLUSION: LTD4 stimulates proliferation of cultured human ASMC and may play a role in airway remodeling of asthma.  相似文献   
123.
AIM: To study the expression and its kinetics of rice phenylalanine ammonia-lyase gene encoding into E. coli as the basis of treatment for phenylketouria. METHODS: The phenylalanine ammonia-lyase-1-cDNA(rPAL-1-cDNA) from rice was recombined into E. coli high expression vector pET-28c and transformed into E. coli host strain BL21DE3. Engineering bacteria was then inducted by isopropyl-β-D-thiogalactoside (IPTG) for 1, 3, 5, 7 hours, in order to obtain high level expression. RESULTS: After induction, the expression level of fusion protein was 21.40%, 30.60%, 35.40%, 35.43% respectively. The fusion protein exhibited a band of 78.6 kD on SDS-PAGE analysis, but was not found in controls.The target protein was mainly existed in the form of inclusion body. CONCLUSION:Rice PAL gene expressing E. coli was established by gentic engineering technique.  相似文献   
124.
AIM and METHOD: The adhesion behavior of bone marrow stromal cells(BMSC) in children with acute lymphoblastic leukemia(ALL) to bone marrow mononuclear cells(BMMC) and Raji cells were investigated by MTT method. The expression of adhesion molecules ICAM-1 and VCAM-1 were detected by flow cytometry. RESULTS: The adhesion ability of BMSC in acute period of ALL to BMMC was lower than that of control group. The adhesion ability of BMSC in long term remission period of ALL to Raji cells higher than that of control group. The expression of ICAM-1 on the surface of BMSC in acute period of ALL is much lower than that of control group. CONCLUSIONS: The adhesion of BMSC to BMMC or tumor cells in children with ALL was abnormal. The abnormal adhesion behavior might be partially due to the changed expression of adhesion molecules on BMSC.  相似文献   
125.
AIM To observe the effect of adriamycin/doxorubicin (DOX) on the production of inflammatory cytokines and collagen in cardiac fibroblasts and its mechanism. METHODS Neonatal SD rat cardiac fibroblasts were isolated, cultured, and identified by immunofluorescence staining with monoclonal antibodies against vimentin observed under a confocal laser-scanning microscope. The Cell Counting Kit-8 assay was used to detect the toxicity of DOX on cardiac fibroblasts, and flow cytometry with annexin V-FITC/PI double staining was used to detect apoptosis. ELISA was used to detect the release of inflammatory factors in the supernatant of cultured cells. Immunofluorescence labeling assay was used to detected α-smooth muscle actin (α-SMA) expression and mitochondrial reactive oxygen species (mROS) in the cells. Western blot was used to detect the expression of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome-related proteins in cardiac fibroblasts. RESULTS (1) Compared with the control group, DOX inhibited the proliferation of cardiac fibroblasts (P<0.05), but had no significant effect on apoptosis (P>0.05). (2) Treatment with DOX promotes the release of proinflammatory factors interleukin-1β (IL-1β) and IL-6 in cardiac fibroblasts (P<0.05). (3) The expression of α-SMA, collagen type I and transforming growth factor-β in DOX treatment group increased significantly compared with control group (P<0.05). (4) Compared with the control group, the levels of mROS, cellular NLRP3 and cleaved caspase-1 in cardiac fibroblasts increased significantly after DOX treatment. CONCLUSION Doxorubicin promotes cardiac fibroblasts to secrete IL-1β and collagen type I by promoting mROS production and activating NLRP3 inflammasome.  相似文献   
126.
AIM To investigate the activation of related repair pathways after bupivacaine-induced neuronal DNA damage by cDNA gene screening. METHODS The bupivacaine-induced SH-SY5Y neuronal damage and DNA damage model was established. The technique of cDNA microplate array was used to screen the 21 important regulatory factors in the DNA damage repair pathway. Post-analysis of these differentially expressed repair genes for the repair pathway enrichment and distribution was performed. The data were analyzed by GraphPad Prism 6 statistical software to compare differences between groups. RESULTS The viability of SH-SY5Y cells treated with bupivacaine at different concentrations (detected by CCK-8 assay) showed that the IC50 value of bupivacaine was 1.5 mmol/L. The comet assay related index (the comet tail) was increased (P<0.05), the phosphorylation level of γH2AX protein was increased (P<0.05), indicating that DNA damage in the SH-SY5Y cells was significantly aggravated after bupivacaine treatment. The results of cDNA microplate assay showed that compared withcontrol group, the differentially expressed genes after bupivacaine treatment were DNA-PKcs, PTEN, NTH1, RAD9, CSB, GADD45, XPD, XPC-HR23B and P53. The analysis showed that these repair genes were mainly concentrated in the following 3 repair mechanisms: base excision repair, nucleotide excision repair, and non-homologous reconstitution. CONCLUSION The repair genes differentially expressed after neuronal DNA damage caused by local anesthetics are mainly concentrated in the pathways of non-homologous end-joining, base excision repair and nucleotide excision repair.  相似文献   
127.
AIM To investigate whether interleukin-1β (IL-1β) regulates endothelial nitric oxide synthase (eNOS) phosphorylation at Ser1177 site in human umbilical vein endothelial cells (HUVECs), and to explore its possible mechanism. METHODS The HUVECs were randomly divided into normal control group, tumor necrosis factor-α (TNF-α) group, IL-1β group, IL-6 group, SC79 [protein kinase B (PKB/AKT) specific agonist] group and SC79+IL-1β group. Western blot was used to determine the protein levels of eNOS, p-eNOS-Ser1177, AKT and p-AKT-Ser473 in the HUVECs. Chemical colorimetry was used to detect the nitric oxide (NO) content in the culture medium of HUVECs. RESULTS No statistically significant difference of p-eNOS-Ser1177 level in HUVECs treated with TNF-α and IL-6 was observed as compared with normal control group (P>0.05), while the protein level of p-eNOS-Ser1177 in the HUVECs and the content of NO in the culture medium of HUVECs decreased significantly in IL-1β group (P<0.05), and the protein level of p-AKT-Ser473 in the HUVECs was decreased as compared with normal control group (P<0.05). The AKT agonist SC79 blocked the down-regulation effect of IL-1β on p-eNOS-Ser1177 level in the HUVECs and NO content in the culture medium of HUVECs (P<0.05). CONCLUSION IL-1β down-regulates the protein level of p-eNOS-Ser1177 in HUVECs and affects the activity of eNOS, which may be involved in AKT/eNOS signaling pathway.  相似文献   
128.
氯丹和灭蚁灵在污染场地中的空间分布研究   总被引:9,自引:1,他引:8  
氯丹和灭蚁灵是两种杀虫剂类POPs,在我国仍然生产和使用。在多年生产氯丹、灭蚁灵的企业厂区内及周围布设采样点,采取不同深度的土壤进行分析,研究了POPs生产企业土壤中污染物的空间分布规律。结果表明,生产厂区内污染严重,在土壤表层,靠近生产车间的土壤中氯丹的浓度高达2927.95mg·kg-1,灭蚁灵浓度高达61.90mg·kg-1,并且已经扩散到周边土壤。在土壤深层,氯丹和灭蚁灵有明显的垂直扩散,10m深处土壤均能检出两种污染物。由于灭蚁灵产量小于氯丹产量,灭蚁灵的污染不及氯丹的污染严重。  相似文献   
129.
采用田间试验方法,研究了莫比朗在柑桔和土壤中的消解动态和最终残留。样品用乙腈提取,过Envi-Florial固相小柱净化,液相色谱紫外检测器检测,外标法定量。残留动态试验结果表明,施药浓度为推荐剂量的两倍时(有效成分120g·hm-2),莫比朗在柑桔中的半衰期分别为7.00~8.90d,土壤中为4.00~6.38d。在有效成分为60g·hm-2的剂量下,施药3次,施药后第21d柑桔中莫比朗残留量低于0.10mg·kg-1。  相似文献   
130.
2022-2023年在河南和海南以玉米自交系驻85、驻136、ZM3358为试验材料,研究自交系苞叶与穗轴同步发育特性。结果表明,河南苞叶驻85第1~7 d伸长迅速,速增期与ZM3358一致,低于驻136;穗轴,驻85第1~11 d急剧伸长。海南苞叶ZM3358伸长速增期为13 d,比驻85、驻136延长2~3 d;穗轴ZM3358伸长渐增期最长为19 d,显著高于驻85、驻136。河南苞叶驻85宽度持续变宽,驻136苞叶宽度第11 d开始增幅变缓,ZM3358苞叶宽度速增期最短为7 d;穗轴粗度驻136第1~17 d持续变粗,第19 d稍有下降。海南ZM3358苞叶宽度速增期为13 d,驻85、驻136苞叶宽度速增期均为9 d;驻85穗轴粗度速增期最长为19 d,苞叶与穗轴可保持同步发育特性。  相似文献   
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