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41.
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利用生物传感器——表面等离子共振传感器建立在活体动物中检测朊蛋白的方法,依据抗原—抗体特异性原理检测牛奶中朊蛋白。结果表明:应用表面等离子共振技术进行检测,1 h以内即可达到在缓冲液中标准最低检测限30 ng/mL的水平,牛奶样品的最低检测限是120 ng/mL。 相似文献
43.
非淀粉多糖酶对奥尼罗非鱼生长及抗菌力的影响 总被引:5,自引:0,他引:5
本文旨在研究非淀粉多糖酶对奥尼罗非鱼的生长及其抗菌力的影响。试验选用体重约60 g的奥尼罗非鱼(Oreochromis niloticus×O.aureus)560尾,随机分成4个处理组,每组7个重复,每重复20尾奥尼罗非鱼,分别投喂添加不同梯度的液体酶制剂(0、0.1、0.2和0.4 mL/kg的饲料)。结果表明:(1)非淀粉多糖酶对罗非鱼的特定生长率、饲料转化率等生产性能指标均有显著升高(P<0.05);(2)添加非淀粉多糖酶0.2 mL/kg和0.4 mL/kg显著提高了罗非鱼白细胞的吞噬活性(P<0.05)和血清的杀菌能力(P<0.01),试验组各组织溶菌酶活力也显著增加(P<0.05)。 相似文献
44.
电解水浸种对苦瓜种子发芽的影响研究 总被引:2,自引:0,他引:2
研究了电解水浸种对苦瓜种子发芽的影响.研究结果表明.电解水浸种对苦瓜种子发芽有促进作用.采用酸性电解水浸种,发芽势、发芽率和发芽指数均明显提高;采用碱性电解水浸种,不仅能显著提高种子活力,还有有效抑制霉菌的作用. 相似文献
45.
AIM: To investigate the effect of microwave radiation at different intensities on the rat myocardium and its possible mechanism.METHODS: The rats were radiated by the intensity of 500, 1 000, 1 500 and 2 000 W/m2 with 2 450 MHz microwave for 6 min. The heart tissue was collected 6 h after microwave radiation. ATP and mitochondria complex Ⅳ and Ⅴ were measured. The changes of the tissue structures were observed under transmission electron microscope. The apoptosis of the myocardial cells was detected by a cell analyzer. The protein level of cleaved caspase-3 was determined by Western blotting.RESULTS: The concentration of ATP and activity of mitochondria complex Ⅳand Ⅴ signi-ficantly decreased compared with control group in the cardiac tissues. The decreased number, morphological abnormalities such as dissolved cavitation, matrix and obvious tumefaction of mitochondria were observed under transmission electron microscope. The microwave radiation induced the apoptosis of myocardial cells in the rats. The cell apoptotic rate and the protein level of cleaved caspase-3 increased with increasing intensity of microwave radiation(P<0.05).CONCLUSION: Microwave radiation has obvious injury effect on the rat heart, which can cause cardiac energy metabolism dysregulation and cardiac myocyte apoptosis. 相似文献
46.
ZHANG Qiong WAN Chang-wu YU Yan-ni XIA-Bing LIU Jiang-jin ZHANG Qiao-jun LI Zhu WANG Cheng-fei DAI Jia-lin WANG Jie 《园艺学报》2021,36(12):2133-2138
AIM To explore the possible mechanism of cathepsin C (CTSC) and tumor necrosis factor-α (TNF-α) in coronary heart disease (CHD) by detecting the protein expression of CTSC and TNF-α in human coronary artery tissue. METHODS The coronary artery tissues from 52 cases of CHD and 25 cases of accidental death without any heart disease in the Forensic Judicial Expertise Center of Guizhou Medical University from October 2018 to December 2019 were collected as CHD group and control group, respectively. The coronary artery stenosis and intimal plaque formation were examined by histopathology, the protein expression of CTSC and TNF-α was determined by Western blot, and the intracellular expression of CTSC and TNF-α was analyzed by immunohistochemical staining. RESULTS The results of HE staining showed that the intima of coronary artery in control group was smooth, and no thickening or stenosis was observed. In CHD group, the intima thickened irregularly, atherosclerotic plaques formed, the intima became thinner and the lumen showed eccentric stenosis in varying degrees (P <0.05). The results of Western blot showed that the expression of CTSC and TNF-α in CHD group was significantly higher than that in control group (P <0.05). Immunohistochemical staining showed that both CTSC and TNF-α were expressed in the cytoplasm of foam cells, and their positive expression was significantly higher than that in control group (P <0.05). The results of Pearson moment correlation analysis showed that there was positive correlation between the expression of CTSC and TNF-α in CHD (r2 =0.743, P <0.05). CONCLUSION The up-regulated expression of CTSC in coronary artery tissue may promote the expression of TNF-α and affect the occurrence and development of CHD. 相似文献
47.
为探究三峡水库典型支流小江太湖新银鱼(Neosalanx taihuensis)种群摄食对浮游动物群落结构的影响,于2019年1~12月逐月对太湖新银鱼与浮游动物样品进行采集并分析太湖新银鱼胃含物组成与浮游动物群落结构特征。分析结果表明:(1)太湖新银鱼的饵料生物主要为桡足类(相对重要指数百分比(IRI%)=79.97%),其次为枝角类(IRI%=18.86%),轮虫占比较少(IRI%=0.001%)。(2)3至6月(太湖新银鱼春群繁殖期)太湖新银鱼生物量迅速上升,并在5、6月维持较高水平的生物量,而浮游动物群落结构呈现小型化趋势,生物量由28.93 mg/L下降至1.13 mg/L;密度由21173.39 ind./L增加至26808.23 ind./L。7月小江禁捕结束,太湖新银鱼生物量开始急剧下降,小江浮游动物中桡足类和枝角类的密度与生物量迅速升高,于8月(密度为151.98 ind./L;生物量为3.39 mg/L)达到全年最高。(3)在太湖新银鱼生物量较高的时期,由于太湖新银鱼对于枝角类和桡足类具有较强的选择性,导致水体中枝角类和桡足类生物量占比(17%~58%)显著低于其它时期(P<0.05)。由此认为,太湖新银鱼生物量与浮游动物群落结构变化存在较强的关联性,太湖新银鱼种群摄食的下行效应可能是小江浮游动物生物量下降及群落结构小型化的关键原因。明晰太湖新银鱼种群生长与浮游动物群落结构的动态变化关系可为小江水华暴发的控制与水生态健康管理提供理论依据。 相似文献
48.
49.
WAN Jian-xin GUO Qi WANG Jing-han PAN Yang-bin CUI Jiong FU Bin-bin XU Yan-fang 《园艺学报》2009,25(8):1628-1634
AIM: To observe the effects of cytokines on renovation of acute renal failure (ARF) in mouse with bone marrow derived mesenchymal stem cell (MSC) transplantation. METHODS: ARF animal model was induced in mouse by subcutaneous injection of cisplatin. Mice were randomly assigned into 3 groups: normal control group, ARF group and MSC group. After 24 h cisplatin injection, animals were injected intravenously with MSC in MSC group. Animals were sacrificed at 1 d, 4 d, 7 d, 14 d and 28 d after cisplatin injection. The blood urea nitrogen (BUN) and serum creatinine (Scr) were measured. The renal morphologic changes were scored with Paller’s criterion on hematoxylin and eosin (HE) stained sections. The mRNA and protein expressions of HGF, BMP-7, TNF-α and IL-10 were detected by RT-PCR and immunohistochemistry method. RESULTS: After 4 d of cisplatin injection, the BUN and Scr values in MSC group were significantly lower than those in ARF group (P<0.01). After 7 d and 14 d, the values of BUN and Scr in MSC group were still lower than those in ARF group (P<0.01, P<0.05). The renal morphologic scores of MSC group were also lower than those of ARF group. After 7 d, the expressions of HGF, BMP-7 and IL-10 were higher in MSC group than those in ARF group, the expression of TNF-α in MSC group was lower than that in ARF group. CONCLUSION: MSC promotes the recovery of acute renal failure induced by cisplatin. The mechanism may partly depend on paracrine of growth factor and amelioration of inflammatory. 相似文献
50.
为充分阐明草皮生产对其生产基地土壤质量的影响,对长春市二道区朝阳沟草皮基地连续草皮生产7年土壤;哈尔滨市松北区乐业镇魏家屯连续草皮生产8年土壤40个样本进行了土壤性质测试分析与探讨。结果表明:连续7、8年草皮生产后,其基地土壤比表面增加;微团聚体组成中,〈0.001 mm,0.001~0.005 mm粒级均增加,0.01~0.05 mm粒级均降低。pH值、CEC(阳离子交换量)、EC(电导率)变幅不大;有机质含量降低,降低幅度达20.00%以上。土壤腐殖质的胡敏酸碳/富里酸碳(HA/FA)比降低。土壤速效氮、磷、钾含量均降低,以磷、钾含量降低幅度较大,分别高达80.00%、65.00%以上。提高了外源施入氮、磷、钾素的吸附能力,降低其释放能力,特别是磷、钾素。调查结果,表明连续7、8年草皮生产对土壤物理性质及土壤肥力造成严重破坏。 相似文献