四种杀虫剂对七星瓢虫和松毛虫赤眼蜂的负效应

七星瓢虫Coccinella septempunctata Linnaeus和松毛虫赤眼蜂Trichogramma dendrolimi Matsumura作为多种害虫的天敌昆虫，广泛应用于生物防治中。本研究按标准采用药膜法分别测定了37%联苯·噻虫胺悬浮剂、24%溴虫腈·甲维盐悬浮剂、45%吡虫·虫螨腈悬浮剂和20%甲维盐·茚虫威悬浮剂四种杀虫剂对七星瓢虫2龄幼虫和松毛虫赤眼蜂成蜂的急性接触毒性，并进行了安全性评价。结果表明：37%联苯·噻虫胺悬浮剂、24%溴虫腈·甲维盐悬浮剂、45%吡虫·虫螨腈悬浮剂和20%甲维盐·茚虫威悬浮剂对七星瓢虫的LR₅₀分别为0.0327、6.90、5.00和1.25 g a.i./hm²，其中24%溴虫腈·甲维盐悬浮剂对七星瓢虫为高风险性，其余药剂为极高风险；对赤眼蜂的LR₅₀分别为2.35×10^-3、0.0129、6.46×10^-3和0.127 g a.i./hm²，均属极高风险。本研究为杀虫剂对七星瓢虫和松毛虫赤眼蜂的负效应影响研究提供一定数据支持。     

Effects of BCL6B on proliferation and migration of human colorectal carcinoma LoVo cells and its potential mechanism

AIM: To detect the endogenous expression of B-cell leukemia/lymphoma 6 member B (BCL6B) in FHC and LoVo cells, and to investigate the effects of BCL6B on proliferation and migration of LoVo cells for further exploring the underlying mechanism. METHODS: The endogenous expression of BCL6B in the FHC and LoVo cells was detected by RT-PCR and Western blot. The methods of MTT assay, colony formation assay, wound healing assay and Transwell chamber experiment were employed to examine the biological functions of BCL6B in the LoVo cells. The mRNA and protein levels of BCL6B, cyclin D1 and matrix metalloproteinase-9 (MMP-9) were determined by RT-PCR and Western blot, respectively. The level of phosphorylated protein kinase B (p-AKT) was detected by Western blot. RESULTS: BCL6B expression was notably repressed in the LoVo cells as compared with the FHC cells, which were significantly increased by transfection with pcDNA3.1-BCL6B. The abilities of proliferation and migration of the LoVo cells at 72 h were inhibited by 28.33%(P<0.01) and 36.11%(P<0.05) in BCL6B group. The mRNA levels of cyclin D1 and MMP-9 in the cells of BCL6B group were decreased by 39.90%(P<0.01) and 77.36% (P<0.05), and the protein levels of cyclin D1, MMP-9 and p-AKT were reduced by 44.00%(P<0.05), 47.06%(P<0.01) and 32.88% (P<0.05), respectively. CONCLUSION: BCL6B inhibits proliferation and migration of the LoVo cells, and the PI3K/AKT signaling pathway is involved in this process.     

Roles of endogenous nitric oxide in acute mountain sickness

Acute mountain sickness (AMS) is the greatest challenge of military medicine and wilderness medicine, as the increasing populations of entering Tibet and others who rapidly ascend to high altitude. AMS is considered as a kind of vascular dysfunction and disequilibrium of body fluid diseases induced by environmental stress. Studies reveal that endogenous nitric oxide (NO), a predominant endogenous vessel dilator, plays a crucial role in the pathogenesis of AMS. The decreased production and blocked delivery of NO cause dysfunction of the vascular system in hypoxic situations. Subsequently, AMS develops under the facilitations of alterations in brain and pulmonary blood vessels. NO or L-arginine (the precursor of NO) can also be used to prevent and treat AMS. This review will summarize the progress on the roles of NO in the pathogenesis, pathophysiology, treatment and prophylaxis of AMS.     

瘦素受体表达量在苏钟猪脂肪沉积调控中的作用

瘦素受体（leptin receptor,LEPR）在机体的体质量平衡、造血、生殖、血管生成和免疫过程中发挥着重要作用。为进一步了解LEPR基因在苏钟猪脂肪沉积调控中的作用机制,本研究利用Real-time PCR方法和Western-blot方法分析该基因在12头苏钟猪中5个脂肪易沉积组织（心脏、肝脏、肾脏、背膘和眼肌）RNA和蛋白水平的表达谱信息。结果表明：LEPR的mRNA在这5种组织中均有表达,其在各组织中的mRNA表达丰度表现为：背膘〉眼肌〉心脏〉肝脏〉肾脏,其中在背膘的表达量极显著高于其他几种组织（P〈0.01）;LEPR蛋白在这5种组织中也均有表达,其中在心脏中的表达量最高,显著高于其他组织（P〈0.01）,且在公猪组织的表达量显著高于母猪组织（P〈0.05）;另外,LEPR第18外显子在苏钟猪群中检测到3个高突变率的SNPs。LEPR对苏钟猪的背膘、肌肉、心脏、肾脏、肝脏等组织的脂肪沉积有重要影响,是苏钟猪肉质改良育种中潜在的重要候选基因。     

Effects of different mulching practices on the photosynthetic characteristics of hot pepper (Capsicum annuum L.) in a greenhouse in Northwest China

Mulching is considered a desirable management technology for improving and stabilizing agricultural crop production. The aim of the present study was to evaluate the effect of different mulching practices on hot pepper (Capsicum annuum L.) performance in terms of leaf photosynthetic capacity, photosynthetic light response (PLR) curves, and growth parameters, under greenhouse conditions. Consequently, field experiments were conducted during the 2011 and 2012 growing seasons in Northwest China using four types of mulching practices (without mulch; wheat straw mulch; plastic film mulch; and combined mulch with plastic film and wheat straw). The results showed that mulching increased the leaf net photosynthesis rate, stomatal conductance to water vapor, intercellular CO₂ concentration, water-use efficiency, and transpiration rate. Mulching significantly affected the PLR curves, and important parameters (such as the apparent quantum yield, maximum net photosynthetic rate, light compensation point, and light saturation point) were all improved under combined mulching conditions when compared with other mulching practices. Therefore, it is inferred that hot pepper leaf photosynthetic capacity and light-use efficiency were significantly improved under combined mulching, and thereby the combined mulching is recommended for hot pepper cultivation in greenhouses due to working well to facilitate soil condition (moisture and temperature), plant growth, and marketable photosynthetic characteristics.     

Simulation of groundwater table dynamics based on Feflow in the Minqin Basin,China

As groundwater table declination is an important factor resulting in degradation of eco-environment in the Minqin Basin,China,it is significant to investigate and understand the groundwater table dynamics in this area. According to the physical and geographical conditions of the Minqin Basin,a hydrogeological conceptual model and a mathematical model were established,and the mathematical model was figured out by using Finite Element subsurface Flow system(Feflow).Accurate hydrogeological parameters were acquired,and the spatio-temporal distribution dynamics of groundwater table for 1983–2001 were also simulated.The model performed well with a correlation coefficient of 0.977 and a mean error of 0.9768 m.The inflow and outflow of the groundwater system were predicted by time series analysis,and the groundwater table dynamics for 2011 were further acquired.Generally the groundwater table in the Minqin Basin would continue to decline.The groundwater table would decline during spring and summer irrigation,while it would rise during autumn-winter irrigation.The groundwater depression cones would expand with the increase of center depths.Therefore,regulatory measures should be taken to prevent the declination of groundwater table and improve the eco-environment of this area.     

醋柳红素胶囊对老龄小鼠的抗氧化作用

本文研究醋柳红素胶囊对老龄小鼠的抗氧化作用。给予老龄小鼠不同剂量的醋柳红素胶囊内容物灌胃，连续30d，检测小鼠血清中超氧化物歧化酶（SOD）活性，全血谷胱甘肽过氧化物酶（GSH—PX）活性和过氧化脂质（MDA）的含量。结果表明醋柳红素胶囊无提高小鼠红细胞SOD活性，能提高GSH—PX活性，显著降低小鼠血中MDA含量，结果显示醋柳红素胶囊具有抗氧化作用。     

对南方油菜生产机械化技术现状的分析及思考

针对南方油菜生产机械化水平较低的现状,结合油菜生产过程中的移栽、播种、收获等主要环节,对南方油菜生产机械化技术现状做了详细阐述,分析了油菜生产机械化存在的主要问题,总结了目前制约油菜生产机械化发展的几个因素:适宜品种问题、种植规模与田块布局问题、种植技术的配套问题、机具性能和可靠性较低的问题等,指明了今后油菜生产机械化技术的发展方向.