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81.
AIM:To investigate the effects of fibronectin (FN) on the proliferation and collagen synthesis in cultured rat cardiac fibroblasts (CFb) derived from SHR (CFbSHR) and WKY (CFbWKY). METHODS:CFb derived from 12-week-old spontaneously hypertensive rat (SHR) and WKY was cultured by outgrowth of tissue block. Cell proliferation of CFb was measured by cell number counting and[3H]-TdR incorporation using 24-well plates pre-coated with 5 μg/cm2 of FN. Collagen synthesis was determined by [3H]-proline incorporation. RESULTS:As compared with control, the cell number of fibroblasts derived from SHR and WKY were significantly increased to 163.75% and 170.42% respectively after 72 h incubation with FN in the presence of 0.4% FCS from a intial cell density of 1×104 cells/mL. DNA synthesis of CFb was markedly promoted by FN. FN induced an increased in [3H]-proline incorporation in both CFbSHR and CFbWKY. CONCLUSION:FN is able to promote cell proliferation and collagen synthesis of CFb derived both from SHR and WKY. 相似文献
82.
十种常用农药与球孢白僵菌的生物学相容性 总被引:24,自引:2,他引:24
球孢白僵菌孢子粉与10种常用农药相容性的测定结果显示,随着孢子浓度上升,所试农药对孢子的抑制作用均有不同程度的增强。在1/10田间常规使用浓度下,百菌清和代森锰锌均能抑制或杀死孢子(萌发率<1%)。除阿维菌素外,所有杀虫剂均与白僵菌孢子相容,在常规使用浓度的10倍稀释液中孢子萌发率达90%以上。吡虫啉、蚜虱灵、灭多威和氟虫腈与孢子的相容性最好,其中吡虫啉和蚜虱灵对孢子萌发率的影响不明显随药剂浓度的变化而变化,即使在田间常规使用浓度下孢子萌发率也在95%以上,而阿维菌素与白僵菌的相容性极差。因此,应用白僵菌制剂防治害虫,选择生物学相容性好的农药以低剂量与白僵菌制剂混用,既可使菌剂增效,又可大幅度降低化学药剂用量。 相似文献
83.
莲子草假隔链格孢的寄主范围及对空心莲子草的控制作用 总被引:18,自引:0,他引:18
空心莲子草(Alteranthera philoxeroides)由于具有繁殖迅速、适应性强等特点,于20世纪50年代被引人我国江苏和浙江等地作为牲畜饲料植物栽培,随后相继传人全国各地并引起危害,成为我国大部分省区旱地和水域的恶性杂草之一。其微生物防治目前仍处于生物防治物的调查筛选阶段,已发现的病原真菌有假隔链格孢菌(Nimbya alternantherae)、炭疽菌(Colletotrichum gloeosporioides)、立枯丝核菌(Rhizoctonia solani)及链格孢(Alternaria sp.)等。 相似文献
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86.
AIM: To investigate the effect of berberine (Ber) on the activation and proliferation of T lymphocytes and its mechanism of action. METHODS: Whole peripheral blood from normal subjects was stimulated with phytohemagglutinin (PHA) or phorbol ester (PDB) plus ionomycin (Ion) and the expression levels of CD69 and CD25 were evaluated with flow cytometry after the staining with appropriate fluorescent monoclonal antibody. The distribution of cell cycles was analyzed by propidium iodide staining and dead cells by 7-aminoactinomycin live staining. RESULTS: 100 μmol/L and 50 μmol/L of Ber had significant inhibition of the expression of CD69 on T cells stimulated with PDB plus Ion or PHA, while effect of 25 μmol/L Ber was not significant. And as time of action extended, the extent of inhibition decreased. For the expression of CD25, Ber at the concentrations as above all exerted significant inhibitory effect in a dose-dependent manner. Moreover, Ber could block lymphocytes cell cycle progression from G0/G1 phase to S and G2/M phase without phase specificity. Besides, live staining analysis revealed that Ber did not have significant cytotoxicity on lymphocytes. CONCLUSIONS: Ber significantly inhibits the expression of early and mid activation antigens of T cells and also blocks the progression of lymphocytes cell cycles. These results suggest that Ber exerts immunosuppression effect through inhibiting the activation and proliferation of T cells. 相似文献
87.
AIM:To investigate the mechanism responsible for albumin microbubbles adherence to activated leukocytes. METHODS: In vitro studies were performed in which activated or nonactivated leukocytes were incubated with albumin microbubbles and observed under microscopy. The suspensions of leukocytes and microbubbles which contained or absented of integrins were analyzed with flow cytometry.RESULTS: A minimum of 50cells were identified under transillumination. 5 min after microbubbles were incubated with leukocytes, the number of cells interacting with microbubbles was greater for activated cells than for nonactivated cells(20.30±2.67 vs 4.50±1.43, P <0.01).Microbubbles attached to the surface of activated leukocytes were phagocytosed and remained intact for up to 30min. Microbubble attachment was inhibited notably by blocking the leukocyte β2-integrin Mac-1(P <0.01) and by VLA-4mAb slightly(P <0.05) CONCLUSION: The mechanism of albumin microbubbles attaching to and phagocytosed by leukocytes was due to β2-integrin and VLA-4 mediation. Phagocytosed microbubbles can remain at the regions of inflammation for15 min, also responsible to ultrasound. 相似文献
88.
89.
应用Kromasil-C18色谱柱(250 mm×4.6 mm,5 μm),WatersTM480型可调波长紫外检测器,0.01M磷酸钾(pH=7):乙腈(3:1)为流动相,检测波长265 nm,含量测定采用标准曲线法,建立了RP-HPLC法检测绵羊尿中克洛素隆含量的方法.方法有效性评价结果表明,尿药含量在0.01~5.0μg/ml及5.0~30.0μg/ml范围呈良好线形关系(r=0.9993、0.9995),方法平均回收率99.32%,日内、日间变异系数分别为3.91%、6.28%.尿药最低检测限0.005μg/ml.试验绵羊以7 mg/kg单剂量经静脉、肌肉及口服三种途径给药后,尿中药物浓度分析表明,克洛素隆经体内处理后主要经肾脏排泄,给药96 h内,静注经尿排泄原药为81.76%,肌注为64.03%,口服为48.50%. 相似文献
90.