三尖杉枝叶粉末防治花生根结线虫病

采用盆栽及大田小区试验,研究了三尖杉Cephalotaxus fortunei枝叶干粉末对花生根结线虫病的防治效果.盆栽试验结果表明,每盆(2kg土)施用三尖杉枝叶干粉末10、15及20 g三种处理,与对照组相比,初侵染相应推迟4、6、10天,并能减少侵染量,降低根结增长率,显著减轻花生根结线虫病病情.大田小区试验结果与盆栽试验结果相似,每小区(5m2)沟施三尖杉枝叶干粉末120、80、50 g,处理后34及53天的2次平均防治效果分别为89%、82%及50%,施药对照10%益舒宝颗粒剂25g处理(相当于45kg/hm2)为74%.综合使用剂量及花生生长情况,建议沟施150kg/hm2三尖杉枝叶干粉为宜.     

Characteristics in the secretion of liver TNF-α induced by infusion of LPS into veins in goats

AIM: To study the role of liver in immune regulation in experimental endotoxemia. METHODS: 17 castrated male goats were subjected to simultaneously installing catheters in jugular, hepatic and portal veins by surgery. Four days later, lipopolysaccharide (LPS) was infused in term of three groups as followings: In group ①, LPS of 20 EU (endotoxin unit, EU)·kg^-1 was infused into portal vein; In group ②, LPS of 20 EU·kg^-1 was infused into jugular vein and LPS of 1 500 EU·kg^-1 infused into jugular vein in group ③. Before and after infusion, blood samples were collected from the three veins through the catheters for 8 h.The plasma levels of TNF-α were measured by RIA. RESULTS: In group ①, the plasma TNF-α levels of hepatic and portal vein rose to peak value at 5 h, but that of the jugular vein did not changed. In group ②, the plasma TNF-α levels in hepatic vein rose to peak value at 3 h. The TNF-α levels of jugular vein rose to peak value at 1 h and the one in portal vein enhanced continuously between 0-8 h. In group ③, the plasma TNF-α levels in jugular, hepatic and portal vein rose to significant peaks at 1 h simultaneously. CONCLUSION: During experimental endotoxemia,liver showed different dynamic characteristics in TNF-α secretion according to the pathway and doses of LPS delivery.     

Expression of cyclooxygenase-2 in IL-1β-stimulated mesangial cells is medicated by NF-κB/IκB signal pathway

AIM: To investigate the role of NF-κB/IκB signal pathway in the regulation of cyclooxygenase-2 (COX-2) expression in human mesangial cells (HMC). METHODS: The PGE₂ concentration in supernatants of HMC was measured by radioimmunoassay. COX-2 mRNA and protein expression were determined by RT-PCR and Western blot. Electrophoretic mobility shift assay (EMSA) and Western blot were used to detect the activity of NF-κB and degradation of IκB. RESULTS: IL-1β significantly upregulated COX-2 expression and PGE₂ production in HMC. Significant up-regulation of NF-κB activation, nuclear translocation of p65 subunit, and degradation of IκB α and IκB β were observed in IL-1β-induced HMC. CONCLUSION: Expression of COX-2 in IL-1β-induced HMC is mediated by NF-κB/IκB signal pathway.     

北京春季沙尘天气特征和预报

根据北京地区资料分析了沙尘的年代变化、月变化,春季是沙尘天气的高发期并以浮尘和扬沙为主。造成沙尘天气的冷空气主要有三条路径,它与蒙古气旋、冷锋、高空急流等大尺度天气系统紧密相连。     

农民旅游市场开发浅议

近几年 ,我国国内旅游发展迅速 ,城镇居民旅游市场日益成熟 ,无论出游人口还是旅游花费都明显增加 ,但农民旅游市场却没有得到应有的重视 ,旅游供给严重不足。鉴于农民旅游的重要地位 ,本文分析了当前农民旅游特征及其发展潜力 ,在此基础上尝试性地提出了开拓农民旅游市场的几点措施建议。     

侧沟茧蜂触角感觉器的扫描电镜观察

扫描电镜观察表明：侧沟茧蜂Microplitis sp．的触角上存在5种感觉器，分别为毛状感觉器A型、B型、C型，槽状感觉器，锥形乳头状感觉器，刺形感觉器和钟形感觉器。对触角感觉器的形态和分布进行了描述，并对两性间的差别进行了讨论，为研究该蜂寻找生境和寄生行为提供依据。     

Mariner转座子与小菜蛾抗性关系的研究

以抗溴氰菊酯、杀虫双、杀螟丹小菜蛾种群及其敏感品系为研究对象,借助聚合酶链式反应(PCR)、载体筛选、琼脂糖凝胶电泳等实验技术,检测了小菜蛾4个品系的Mariner转座子的存在及其与抗性的关系。结果表明,在抗溴氰菊酯、杀虫双、杀螟丹以及敏感品系的小菜蛾中都存在两种大约500 bp的Mariner转座子片断,初次证明在小菜蛾4个品系中均含有两种Mariner转座子,并发现一种新的转座子基因片断,但是没有发现Mariner转座子与抗性之间存在直接的联系。研究结果将为利用Mariner转座子标签法在小菜蛾中分离定位基因、转化外源基因、转基因昆虫防治害虫等研究提供理论基础。     

Osmolarity,cell volume and proliferation in nasopharyngeal carcinoma cells

AIM: To investigate the relationship between osmolarity, cell volume and cell proliferation in nasopharyngeal carcinoma cells. METHODS: MTT method was applied to detect the proliferation ability of the poorly-differentiated nasopharyngeal carcinoma cell (CNE-2Z) under various osmolarity conditions. The flow cytometry was used to analyse cell cycle distribution. Cell volume was obtained by the image analysis of living cells and cell viability was determined by the trypan blue assay. RESULTS: Cultivation of cells under the hypertonic conditions of 370 and 440 mOsmol/L increased cell volume by 8.7% and 27.8% and facilitated cell proliferation by 22.2% and 33.9%, respectively. However, hypotonic incubation of cells with osmolarity of 160 and 230 mOsmol/L decreased cell volume by 12.8% and 4.1% and inhibited cell proliferation by 34.0% and 15.6%, respectively. Cell volume was positively correlated with cell proliferation rate. Long-term cultivation of cells under anisotonic conditions did not significantly alter cell cycle distribution, but hypotonic cultivation decreased cell viability. CONCLUSION: Proliferation of nasopharyngeal carcinoma cells was closely correlated with the osmolarity of culture medium and cell volume. Hypotonic cultivation may inhibit cell proliferation by decreasing cell volume to facilitate cell death mechanisms.     

Influence of Sini decoction on the proliferation and apoptosis of artery smooth muscle cells after balloon injury

AIM: To investigate the influence of Sini decoction (SND) on the proliferation and apoptosis of rabbit abdominal aorta smooth muscle cells after ballon injury and discuss the effect of vascular smooth muscle cell's (VSMCs) proliferation and apoptosis in post-percutaneous coronary intervention (PCI) restenosis (RS) and the feasibility of SND preventing post-PCI RS. METHODS: The animal model of rabbit abdominal aorta ballon injury was set up and the therapertic group was treated with SND. The shape of proliferative and apoptotic cell were investigated by electron microscope. Immunohistochemistry staining was performed using α-actin,PCNA and Cyclin E monoclonal antibodies. In situ Cell Death Detection Kit was used to identify apoptotic cells. Abdomial aorta angiography was operated in the 84th day subgroup and the stenosis degree was evalued by quantitative angiographic analysis. RESULTS: As compared with the control group, the therapeutic group displayed a lower proliferative percentage and a higher apoptosic percentage (P<0.05). Moreover, the apoptosic peek time was on the 14th day after operation,which was longer than the control group. CONCLUSION: SND effectly inhibited the proliferation of VSMCs and iuduced apoptosis in VSMCs.