小肽对大黄鱼仔鱼生长和小肠发育的影响及其在低温胁迫下的抗氧化应激效应

本试验分为生长试验和低温胁迫试验2部分.先分别投喂大黄鱼(Larimichthys cro-cea)仔鱼经不同浓度(0、0.5、1.0、2.0和3.0 mL/m3)小肽营养强化后的轮虫和卤虫12 d,以探讨小肽对大黄鱼仔鱼生长和小肠发育的影响;再将大黄鱼仔鱼暴露在温度为12℃的水体中24 h,以探讨小肽对低温胁迫下大黄...     

Effect of dietary vitamin B6 supplementation on growth and intestinal microflora of juvenile golden pompano (Trachinotus ovatus)

In order to investigate the dietary vitamin B₆ (VB₆) requirement for juvenile golden pompano, an experiment of six different diets with six dietary VB₆ levels (0, 3.75, 7.47, 10.6, 13.7 and 18.5 mg/kg) was conducted. The results indicated that the content of dietary VB₆ significantly increased weight gain rate (WGR), specific growth rate (SGR) and feed conversion ratio (FCR; p < 0.05). Golden pompano fed diet containing 7.47 mg/kg VB₆ achieved the maximum ALT, AST, GPx, hepatic VB₆ concentrations as well as the minimum MDA, however, the ALT, AST, GPx and hepatic VB₆ concentrations decreased while MDA increased with a further increase in dieatry VB₆. The highest values of GR and POD occurred at the 10.6 and 13.7 mg/kg dietary VB₆ (p < 0.05) respectively. A diet supplemented with 7.47 mg/kg VB₆ increased intestinal Na⁺, K⁺‐ATPase, Chymotrypsin, γ‐glutamyl transpeptidase, creatine kinase and amylase activities (p < 0.05). The relative abundance of Tenericutes and Bacteroidetes decreased while Proteobacteria and Firmicutes improved with an increase in dietary VB₆ levels up to 7.47 mg/kg. Quadratic regression analysis on WGR, hepatic VB₆ concentrations, AST and ALT indicated that the optimum dietary VB₆ levels for juvenile golden pompano were 8.84–9.28 mg/kg.     

Regeneration of adventitious shoots from mature stored cotyledons of Japanese plum (Prunus salicina Lind1)

Adventitious shoot regeneration from mature stored cotyledons of Japanese plum (Prunus salicina Lind1) was achieved in vitro. The influences of the presence and absence of the light, different concentrations of thidiazuron (TDZ) and benzyladenine (BA) in the culture media, TDZ pretreatments and different basal salts on shoot regeneration were evaluated. TDZ was more effective in inducing shoot regeneration from mature stored cotyledons than BA. Dark incubation significantly increased the regeneration frequencies. Quoirin/Lepoivre (QL) basal salts stimulated shoot regeneration more than woody plant (WPM) or B5 salts did. The frequency of adventitious shoot formation varied among the varieties and the regeneration ability appeared to be genotype depended. The frequency of regeneration under the optimum tested conditions for ‘Bruce’, ‘Shiro’, ‘Redheart’, ‘Gladstone’ and ‘Early Golden’ cotyledons were 66.7%, 46.7%, 43.3%, 26.7% and 6.7%, respectively.     

An assessment of the variation in the prevalence of renal myxosporidiosis and hepatitis in wild brown trout, Salmo trutta L., within and between rivers in South-West England

The prevalence of renal myxosporidiosis in wild brown trout, Salmo trutta, in seven river catchments in South-West England was investigated. Three hundred and twenty-seven fish were sampled from 16 sites, of which 54 (16.5%) were found, by histological examination of the kidney, to be infected with Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease. No T. bryosalmonae infected fish were found in one river catchment, in other catchments the prevalence ranged from 2.5% to 36%. Hepatitis was strongly associated with the presence of T. bryosalmonae (odds ratio = 20.2, P < 0.001). Chloromyxum schurovi was found in 25% of fish and in six of seven river catchments, where the prevalence ranged from 2.4% to 63%. There was a strong negative association between the presence of T. bryosalmonae and C. schurovi (odds ratio = 0.10, P < 0.001). A hierarchical binomal model of the variance indicated that for T. bryosalmonae most of the variance existed at the site level, whereas for C. schurovi most variance existed at the river catchment level, suggesting that prevalence of T. bryosalmonae infection is determined largely by site level factors (e.g. presence of alternate host). The intraclass correlation coefficients (ICC) were 0.2 and 0.4 for T. bryosalmonae and C. schurovi, respectively, indicating the latter has higher effective transmission because of a higher level of infectiousness and/or abundance of alternate oligochaete hosts. These values can be used in future studies to estimate the sample sizes required to generate prevalence estimates with the required precision.     

林改宗地数据的网络共享与管理

随着集体林权制度改革的全面展开,宗地信息的网络共享与管理成为一个急需解决的问题。以昆明市宜良县林权制度改革宗地数据为例,基于ASP+HTML+Microsoft SQL Server,采用B/S结构设计实现了宗地数据的网络共享与管理。ASP开发简单而且直观,开发过程易于HTML集成。系统操作简单,维护方便,可让不同用户通过网络获取所需的宗地信息,以及对数据进行管理与维护。     

硼肥在水稻生产上应用效果对比试验

通过在水稻苗期、初花期、齐穗期和灌浆期喷施不同种类的硼肥与空白对照进行对比试验,结果表明:喷施硼肥可增强植株的抗逆性,有利于减少水稻病害的发生,还可改善株型,增强抗倒伏能力;喷施硼肥可以增加水稻的株高、穗长、分蘖数、穗粒数、结实率和千粒重,可以提高水稻产量,各处理的产量均高于对照,增产55.2～93.4 kg/667 m2,增产率12.4%～17.6%,其中产量最高的是速乐硼30 g/667 m2,实际产量达624.1 kg/667 m2,增产率17.6%,增产效果显著。     

Deferoxamine Compensates for Decreases in B Cell Counts and Reduces Mortality in Enterovirus 71-Infected Mice

Enterovirus 71 is one of the major causative agents of hand, foot and mouth disease in children under six years of age. No vaccine or antiviral therapy is currently available. In this work, we found that the number of B cells was reduced in enterovirus 71-infected mice. Deferoxamine, a marine microbial natural product, compensated for the decreased levels of B cells caused by enterovirus 71 infection. The neutralizing antibody titer was also improved after deferoxamine treatment. Furthermore, deferoxamine relieved symptoms and reduced mortality and muscle damage caused by enterovirus 71 infection. This work suggested that deferoxamine has the potential for further development as a B cell-immunomodulator against enterovirus 71.     

高校实验室信息管理系统的设计与实现

基于对高校实验室科学化、网络化管理的目的,采用查阅大量相关文献资料,分析国内外研究现状,进行系统设计、实现,并通过实践验证研究效果的技术路线,构建了基于B/S结构模式的高校实验室信息管理系统。通过在河北农业大学基础化学实验室的具体应用,达到了实验室无纸化办公、高效率管理的效果。     

选育甘蓝型春油菜波里马不育胞质三系杂种的研究

在青海春油菜生态区的田间试验结果表明,长江中游的单,双低半冬性甘蓝型油菜品种资源,绝大部分能正常生长适时成熟,这些品种资源与波里马细胞质雄性不育材料测交和连续回交,大部分半冬性品种的回交后彻底不育,而春性品种的后代出现微粉。半冬性品种转有的不育系或恢复系与春性品种转育的恢复纱或不育系配制的杂种优势明显。今后春油菜区在马不育胞质三系杂种的选育,应用长江中游双低半冬性品种（系）转育的不育系与加拿大和欧     

乌贼墨多糖提取物的制备及其对B16F10细胞的影响

为了探索乌贼墨多糖(SIP)对体外培养的B16F10细胞的生物学效应,以乌贼墨为原材料,对SIP进行提取分离,并研究SIP提取物对B16F10细胞活力、细胞内酪氨酸酶活性及黑色素合成等的影响。结果表明,SIP提取的最优条件为提取温度40℃,料液比1∶3,提取时间4h,提取次数3次,在此条件下SIP得率为14.12 mg·g~(-1)。SIP提取物对B16F10细胞形态有一定影响,对细胞活性、酪氨酸酶活性和黑色素合成均有一定抑制作用,且呈现一定剂量效应。综上可知,SIP提取物能抑制黑色素合成,具有作为美白剂的发展前景,这为乌贼墨合理利用提供了一定科学依据。