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71.
青龙湖冬季浮游植物群落结构及其与环境因子的关系   总被引:1,自引:0,他引:1  
为探究青龙湖浮游植物群落结构特征及其水环境影响因子,确定水体营养化现状,于2016年12(冬季)对青龙湖10个采样点浮游植物种类组成、丰度与生物量以及水质理化指标进行调查分析。结果显示,冬季青龙湖共鉴定出浮游植物5门、17属、50种(含变种),硅藻和绿藻是青龙湖浮游植物优势类群,浮游植物种类组成表现为硅藻-绿藻型;优势类群为硅藻门颗粒直链藻(Melosira granulata)、颗粒直链藻极狭变种(M.granulata var.angustissima)、颗粒直链藻极狭变种螺旋变型(M.granulata var.angustissima f.spiralis)及蓝藻门类颤鱼腥藻(Anabaena oscillarioides)、水华束丝藻(Aphanizomenon flos-aquae),优势种在各采样点分布差异不明显。冬季浮游植物丰度均值为6.71×104个/L,生物量均值为0.07mg/L;各采样点Margalef指数、Shannon-Wiener指数与Pielou指数分别为0.98~2.31、0.61~2.37及0.19~0.84。冗余分析(RDA)表明,pH、溶解氧、溶解氧饱和度、水温与氧化还原电位与青龙湖浮游植物群落结构关系最为密切。Margalef丰富度指数、Shannon-Wiener多样性指数与Pielou均匀度指数评价水质结果为中度污型水平。  相似文献   
72.
AIM:To investigate the expression of nestin, a kind of cytoskeletal protein in cultured murine podocytes and the role of nestin in the maintenance of the podocyte structure.METHODS:The immortalized murine podocytes were cultured. The expression of nestin was determined by immunofluorescence. In differentiated podocytes, the expression of nestin was knock-down by RNAi. The effect of nestin knock-down was examined by Western blotting and immunofluorescence. The projections longer than maximal length of the cell body in which the cells transfected with siRNA and control vector that contained nonhomologous oligo were counted, respectively. RESULTS:Nestin siRNA markedly reduced or abolished nestin expression. In cells transfected with nestin siRNA, the percentage of cells with processes was significantly lower than that in cells transfected with control vector (77.0%±6.3% vs 16.0%±4.6%, n=3, P<0.01). CONCLUSION:Nestin may play an important role in maintaining normal function of podocytes.  相似文献   
73.
AIM: To investigate the role of stress hyperglycemia on condition assessment and predicting prognosis in patients with sepsis. METHODS: The study included 44 patients with sepsis, divided into three groups according to their blood glucose profile within 24 h after admission: patients with stress hyperglycemia (group SH, n=15), diabetes mellitus type 2 (group DM, n=10), and normal glucose levels (group NG, n=19). CD4+/CD8+ ratio, Th1/Th2 ratio and HLA-DR% of the patients were measured within 24 h after admission by flow cytometry as assessment of their immune function. The sepsis-related organ failure assessment (SOFA) scores and acute physiology and chronic health evaluation II (APACHE II) scores of patients were recorded at the same time to analyze whether stress hyperglycemia affects the immune function and the 28 d mortality in patients with sepsis. RESULTS: A higher mortality rate of septic patients with stress hyperglycemia was observed compared to diabetic patients (53.3% vs 10.0%) and group NG (53.3% vs 21.1%). SOFA score and APACHE II score were higher in group SH than those in group DM and group NG while lower levels of human leucocyte antigen DR (HLA-DR) expression and CD4+/CD8+ ratio was found in group SH than those in group DM and group NG. No difference in the levels of Th1/Th2 among the three groups was observed. Non-survivors had higher levels of SOFA score, APACHEⅡ score, Th1/Th2 ratio and HLA-DR%. No difference was detected for CD4+/CD8+ ratio, mean glucose values and age. CONCLUSION: Stress hyperglycemia is associated with decreased immune function and an adverse clinical outcome in patients with sepsis.  相似文献   
74.
[ABSTRACT]AIM: To study the effect of 13-methyltetradecanoic acid (13-MTD), a saturated branched-chain fatty acid, on apoptotic induction in breast carcinoma cell line MCF-7 and its underlying mechanisms. METHODS: Breast carcinoma cell line MCF-7 and normal breast epithelial cells MaEC were treated with solvent or 13-MTD at concentration of 140 mg/L. Apoptosis was analyzed by flow cytometry. Phosphorylation of JNK, p38, FADD and Akt after treated with 13-MTD were detected by Western blotting. RESULTS: 13-MTD effectively induced apoptosis of breast carcinoma cell line MCF-7 and no influence to normal breast epithelial cells MaEC, which were confirmed by flow cytometry analysis, was observed. The results of Western blotting showed that obvious increase in p38 and JNK phosphorylation. No significant difference of FADD phosphorylation was observed. However, evidently decrease in Akt phosphorylation was found after treated with 13-MTD. CONCLUSION: 13-MTD was a new safe, effective chemotherapeutic drug. Its underlying mechanisms are through activating MAPK pathway and inhibiting Akt pathway to induce the cancer cells apoptosis.  相似文献   
75.
LI Zheng  SUN Zi-lin  WANG Li  FANG Ming 《园艺学报》2009,25(8):1621-1624
AIM: To study the effect of fractalkine (CX3CL1, Fkn) on the expression and secretion of matrix metalloproteinase-2 (MMP-2) in cultured human monocyte line U937 cells. METHODS: The cultured U937 cells were incubated with recombinant human Fkn, the supernatant of human renal mesangial cells (HRMC) and Fkn neutralizing antibodies for 24 h. The mRNA expression of MMP-2 was analyzed by RT-PCR. The production of MMP-2 in the supernatant was analyzed by gelatin zymography. RESULTS: The level of MMP-2 mRNA and protein in the cells incubated with recombinant human Fkn decreased compared to control group. Similarly, the level of MMP-2 mRNA in the cells incubated with the supernatant of HRMC reduced compared to control group. However, the level of MMP-2 mRNA and protein in the cells incubated with the supernatant of HRMC adding Fkn neutralizing antibodies increased compared to that incubated with the supernatant of HRMC. CONCLUSION: Fkn inhibits the expression and secretion of MMP-2 in cultured U937 cells. HRMC might mediate the expression and secretion of MMP-2 in U937 cells through Fkn.  相似文献   
76.
野菊嫩茎的组织培养   总被引:2,自引:1,他引:1  
在适宜的培养条件下,利用野菊花的嫩茎作为外植体,用组织培养的方法,在MS培养基上生长良好,获得再生植株.练苗后,成活率达100%,生长势强,茎粗壮叶色浓绿.结果表明:利用组织培养的方式对野菊花进行扩繁,简便易行.  相似文献   
77.
介绍了云南陇川县水田新植和宿根甘蔗的高产高糖种植技术。  相似文献   
78.
随着城镇化水平的不断提高,农村劳动力供给过剩以及城市劳动力相对短缺导致农民工群体的出现。农民工从外在就业表象来看已融入城市社会生活,为城镇补充了劳动力这一基本的要素,带来经济总量的增长与经济结构的变化。但同时也存在一定的分化,农民工与城镇劳动力存在理论上的就业竞争,城市中存在着双重分割的劳动力市场,使农民工与城镇劳动力从属的劳动力市场存在层次上的差别。对农民工与城市劳动力就业状况进行比较研究,并以沈阳市为例,得出两者就业关系的相关结论。分析表明:沈阳市农民工与城镇劳动力个体特征上存在较大差异,两者在就业途径、工作类型与工作条件上有较大不同;农民工与城镇劳动力处于劳动力就业的两个分层上,城镇劳动力由于文化程度较高、接受培训可能性大,因此,尽管平均年龄较农民工稍高,但其下岗人员可以得到政府相关就业政策的扶持,在劳动力市场就业选择时处于较高层次;而农民工由于文化程度较低、平均年龄较小、接受培训比例较低等个体特征,多依靠亲戚朋友及一技之长寻找工作,所从事的工作类型也多是较低的职业与行业。因此,沈阳市农民工与城镇劳动力的就业关系表现应以互补性为主。当地政府应从创造更为宽松的就业环境、加大政府培训力度、改善农民工就业条件等方面入手,促进沈阳市农民工及城镇劳动力充分就业。  相似文献   
79.
农业专业镇是广东省农村经济发展的重要推动力。如今农业专业镇的发展面临着结构调整、产业升级和增长方式转变的巨大挑战,服务平台发展的战略选择对农业专业镇发展至关重要。专业镇的中小微企业服务平台建设发展呈现出以创新为核心、产学研紧密结合的趋势:加快中小微企业服务平台发展,在战略上必须以政府为主导,市场化配合运作,将载体建设与功能培育协同运作,将产学研合作与联盟服务协同运作,将品牌建设与重点扶持紧密结合,形成协同运作体系网。  相似文献   
80.
针对华南地区大豆田杂草防除问题,采用种子库诱萌法和田间药效试验法,研究田间杂草种子库的预测方法,筛选最佳化学防除方案.结果表明:杂草种子库共有杂草7科10属,主要分布在0~ 10 cm的土层,总出草量为6 861株·m-2.田间实际出草种类为6科9属,实际出草量平均为208株·m-2,占土壤杂草种子库总量的3.03%;6种除草剂都具有良好的防除效果,其中7.5%禾阔灵乳油的防除效果最佳,能有效防除禾本科杂草、莎草科杂草以及阔叶杂草,药后45 d鲜重防效仍达到70.7%~72.4%,可使大豆增产20.5%~ 34.5%.  相似文献   
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