基于角色访问控制在农业科研单位网站中的应用

根据农业科研单位网站院所两级管理人员的权限需求分析,将基于角色访问控制应用在网站后台管理用户权限分配系统中,并限制用户＂操作所有信息＂和＂仅操作自己的信息＂,满足了不同层次管理人员权限分配的要求。     

Effects of Sini decoction on the ultrastructure of small intestinal epithelial cells in rats with intestinal ischemia-reperfusion

AIM: To investigate the effect of Sini decoction (SND)on the ultrastructure of small intestinal epithelial cells in rats with intestinal ischemia-reperfusion. METHODS: Thirty-two Sprague-Dawley rats of both sexes were randomly divided into 4 groups: (1) Control group in which sham operation was performed; (2) Model group in which intestinal I/R was produced by clamping super mesenteric artery(SMA) for 1 hour and declamping SMA for 3 hours; (3) SND1 group in which SD (0.6 g/200 g rat) was given via stomach tube 3 d before intestinal I/R; (4) SND2 group in which SD (1.2 g/200 g rat)was given via stomach tube 3 d before intestinal I/R. A strip of small intestine was taken from distal end of ileum for electron microscopic examination. The two-dimensional structural parameters and three-dimensional structural parameters of mitochondria were calculated. RESULTS: (1)Morphological changes of small intestine: In control group, epithelial cells were orderly arranged, with normal mitochondria and intestinal villi. In model group, the gaps between epithelial cells widened. There were a lot of apoptotic cells. Microvilli were short and swelled. Mitochondria were swelled obviously with broken ridges. Endoplasmatic reticulum was severely dilated. In SND1 and SND2 groups, microvilli and epithelial cells were orderly arranged relatively, mitochondria was slightly swelled. (2) Structural parameters of mitochondria: In model group, there were the least mitochondria and the swelling of mitochondria was severe. In SND1 and SND2 groups, the mitochondria was more than that of model group and the swelling were slight. CONCLUSION: Sini decoction can protect small intestine from ischemia-reperfusion injury without dose-dependent effect.     

基于SFA的香菇生产技术效率及影响因素分析

技术效率是影响菇农生产的重要因素之一,以湖北随州市香菇种植户为例,运用随机前沿分析方法(SFA)探讨了农户食用菌生产技术效率及其影响因素。试验结果表明,香菇的生产过程中存在着一定程度的技术效率损失,进一步分析发现,户主受教育程度、是否具备专业技能、家庭劳动力数量、种植规模等因素对香菇农户生产技术效率都具有显著的正效应,而户主年龄、性别、是否担任干部以及是否加入食用菌合作组织等因素对香菇农户生产效率影响不显著,最后,提出了相关的政策启示。     

教育阻断民族地区多维返贫风险的机理与对策

教育阻断民族地区多维返贫风险对于巩固脱贫攻坚成果、有效衔接乡村振兴、走向共同富裕具有重要意义。通过分析民族地区多维返贫风险因素及其成因,在阐释教育阻断返贫风险的内在机理和作用的基础上,从大力发展社会教育,化解返贫风险;建立返贫风险户特殊教育机制;大力开展新民教育,阻断传递性返贫;加强科普教育,实现包容性增长;完善基本公共教育,消除多维返贫风险等方面提出了教育阻断民族地区返贫风险的对策。     

优化的小鼠STO细胞系重编程多功能干细胞的建立

研究鼠胚成纤维细胞系STO (SIM-6-thiogunanie-oualiain)诱导为多功能干细胞(induced pluripotent stem cells),(STO-iPSCs).通过磷酸钙法将连接有Oct4、Sox2、Klf4和c-Myc 4个转录因子的慢病毒载体FUW-OSKM转染293FT细胞包装病毒,然后用病毒感染STO细胞,以干细胞培养条件培养.挑取诱导15d的克隆并在有饲养层和无饲养层的培养体系中培养.对获取的STO-iPSCs进行生物学特性分析,具有典型胚胎干细胞的形态特征,碱性磷酸酶染色呈阳性;qPCR结果表明,表达很高的原癌基因Nanog和Oct4 mRNAs;免疫细胞化学表明,表达胚胎干细胞特异性标志Nanog和Oct4,并且能够体外诱导分化为神经细胞.实验获得了STO-iPSCs,建立了STO-iPSCs无饲养层培养体系.     

应用免疫荧光技术研究水稻条纹病毒(RSV)侵染介体灰飞虱卵巢的过程

由水稻条纹病毒(Rice stripe virus,RSV)引起的水稻条纹叶枯病,在许多水稻种植区引起严重的减产,水稻条纹病毒由灰飞虱(Laodelphax striatellus Fallén)以持久增殖型传播,并可以经卵传播方式以较高的比例传给子代灰飞虱。为研究水稻条纹病毒的经卵传播特性及其侵染介体昆虫卵巢的过程,分别利用RT-PCR和免疫荧光技术检测虫体各个器官以及卵巢的带毒率,结果表明,饲毒后尽管灰飞虱的带毒率有28.6%,但是仅有5.3%的卵巢被病毒侵染。同时在利用免疫荧光技术对饲毒后不同时间灰飞虱卵巢中的RSV进行定位,发现RSV首先在卵巢管柄位置出现,随后侵染滤室细胞及生殖区,最后转移到胚盘细胞。结果认为,病毒可能是在滤泡细胞以及生殖区向正在发育的卵母细胞提供营养时,伴随这些营养物质进入卵母细胞。且生殖区的卵原细胞可发育成卵母细胞和滤泡细胞,我们推测,尽管RSV可伴随营养输送进入卵母细胞,但是最初带毒卵母细胞的病毒可能来源于位于卵巢生殖区的病毒。研究结果提示,RSV可能通过营养输送途径运送至卵母细胞,并最终侵染卵的胚盘细胞     

抚仙湖重金属污染强度、历史及来源的沉积记录

This study focused on the concentration change of heavy metals of sediment cores in heavily polluted north area and less polluted middle area of Fuxian Lake in Southwest China.On the basis of the analysis of Cu,Ni,Ti,V,Pb,Cd,and Zn concentration-depth profiles,the pollution history of heavy metals was studied using ¹³⁷cesium (¹³⁷Cs) dating.The sources of heavy metals were distinguished by normalization of their profiles to aluminum and analysis of heavy metal concentrations of potential source materials.Geoaccumulation index (I_geo) was used to quantify their contamination intensity.The results showed that all the heavy metals found in the Fuxian Lake sediments originated naturally before 1980s.Cu,Ni,Ti,and V were still mainly natural in the north lake after 1980s,Cu,Ni,Ti,V,and Pb were mainly natural in the middle lake at all time,but the concentrations of Pb and Zn in the north lake were influenced by industrial wastes from the phosphorus fertilizer factory and cement plants.In all the lake,the contaminations of Cd and Zn were the results of agricultural cultivation using a large amount of fertilizers and the atmospheric fallouts of dusts from cement plants.At present,the geoaccumulation indices showed that the Fuxian Lake sediments were moderately to strongly polluted by Cd in the middle lake,and unpolluted to moderately polluted by Pb and Zn and strongly polluted by Cd in the north lake.Moreover,the pollution intensities of Cd,Zn,and Pb have been increased since 1980s.     

郑州市夏玉米生物量积累与增长分配规律分析

根据郑州市1994—2006年夏玉米生物量观测资料分析了不同生育期单株各器官的生物量变化和增长分配规律，得出：在玉米整个生长期，单株各器官的重量变化在不同生育阶段不同，结果导致各部分干重占全株干重百分比的差异。总体上看，拔节前叶片增长较快，占比率最高，达68％～88％；叶鞘增长也快但所占比例一直不大，最高时占20％；茎在拔节一抽雄期增长较快，最高时占41％；果穗在抽雄后直线增长，最高时占63％。同时，通过定量分析得到了各器官在整个生育期增长分配率的变化过程，模拟取得不同气候年型生物量积累曲线，研究结果可为当地玉米生长的定量化模拟提供参考。     

DEM内插算法对坡度坡向的影响

虽然DEM的应用越来越广泛,但是在实际研究运用中获取DEM的方式主要是利用各种矢量高程信息通过插值而来,不同的插值算法必然会影响DEM分析的结果;以南方丘陵地区为研究区域,利用样区的1∶10000的矢量地形图为数据源,通过对不同算法生成不同分辨率的DEM坡度、坡向的对比研究发现:在坡度小于30°时,不同的算法对坡度具有显著的影响,而大于30°时分辨率和算法均不会对坡度产生显著影响;研究表明:在具有大量平坦区域的地区,尽管ANUDEM算法生成的DEM总体上的精度最高,但是不会产生平坦区域,所以并不适合于这类地区的地形分析。     

Effect of salvianolic acid B on vasodilatory function,NF-κB activation and inflammatory cytokine expression in diabetic rats

AIM: To investigate the ameliorative effect of salvianolic acid B on vasodilatory function in diabetic rats and the possible mechanisms. METHODS: SD rats (n=40) were fed on high-sugar and high-fat diet for 4 weeks, followed by a single intraperitoneal injection of streptozotocin (40 mg/kg). The rats with random blood glucose level over 16.7 mmol/L were considered diabetic and randomly allocated to 3 groups, namely model group, low dose (80 mg·kg^-1·d^-1) of salvianolic acid B group and high dose (160 mg·kg^-1·d^-1) of salvianolic acid B group. The rats in salvianolic acid B groups were intragastrically administered with corresponding doses of salvianolic acid B for 6 weeks. Vasodilatory function was measured as endothelium-dependent and-independent vasodilation of the aortic rings. The primary histopathological changes of aorta were observed by HE staining. Serum levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were measured by ELISA. The levels of total antioxidant capacity, malondialdehyde (MDA) and nitric oxide (NO) in aortic tissues were evaluated by colorimetric assays. The protein levels of intercellular adhesion molecule-1 (ICAM-1) and monocyte chemotactic protein-1 (MCP-1), and the activation of nuclear factor-κB (NF-κB) were determined by Western blot. RESULTS: Treatment with salvianolic acid B evidently ameliorated endothelium-dependent diastolic function and pathological changes of aorta in diabetic rats (P<0.05 or P<0.01). Supplementation with salvianolic acid B resulted in significant increases in NO content and total antioxidant capacity in aortic tissues, accompanied by marked decreases in the level of MDA in aorta tissues and the serum levels of IL-6, TNF-α and CRP (P<0.05 or P<0.01). Salvianolic acid B markedly down-regulated NF-κB p65 nuclear translocation and protein expression of ICAM-1 and MCP-1 in aorta tissues (P<0.05 or P<0.01). CONCLUSION: Salvianolic acid B effectively ameliorates endothelium-dependent diastolic function of aorta in diabetic rats, which might be attributed to suppression of NF-κB activation and subsequent expression of inflammatory cytokines. The beneficial effect of salvianolic acid B on vascular endothelium might be derived from its antioxidant capacity.