表面技术在内燃机气缸套中的新进展

论述了气缸套的失效机理，针对这一缺点，较全面地阐述了当前表面技术在气缸套上的应用现状，并提出了未来气缸套的发展方向。为同行提供了参考和启迪，也为拓宽热喷涂技术的应用指明了一个方向。     

The potential use of plasma glutamate dehydrogenase activity for the evaluation of hepatic disease in the cockatiel (Nymphicus hollandicus)

A reference interval for plasma glutamate dehydrogenase (GD) (E.C. 1.4.1.3) activity, of 0-8 IU/L, was established for the cockatiel (Nymphicus hollandicus). An automated modification of a commercial manual assay was used. This enzyme is considered liver specific in humans and numerous domestic animals, due to its organ distribution. A similar distribution was found in cockatiels in this study. Maximal enzyme activity was recovered from liver and kidney homogenate supernatants. Minimal activity was detected in skeletal muscle preparations. These results suggest a potential use for plasma GD activity in the evaluation of hepatocelluar injury/necrosis in cockatiels.     

干旱胁迫对蒲公英渗透调节物质、酶保护系统及质膜水孔蛋白PIP2-3基因表达的影响

为了揭示蒲公英在干旱胁迫下渗透调节和酶保护系统的作用机理以及质膜水孔蛋白PIP2-3基因的表达特征,采用盆栽控水试验,研究了不同干旱胁迫RWC=(90±5)%、RWC=(75±5)%、RWC=(50±5)%下蒲公英渗透调节物质、酶保护系统以及质膜水孔蛋白基因的相关表达。结果表明:随着干旱胁迫的加重,蒲公英叶片中的可溶性糖、可溶性蛋白、游离脯氨酸的含量显著增加,超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)的活性显著提高,在轻度胁迫(MS)中呈持续上升的趋势,重度胁迫(SS)中则呈现先升高后下降的趋势(可溶性糖除外);质膜水孔蛋白PIP2-3基因的相对表达量上调,轻度胁迫(MS)显著高于重度胁迫(SS)。复水7 d后,渗透调节物质的积累以及SOD的含量下降,但仍显著高于CK,POD、CAT的含量以及质膜水孔蛋白PIP2-3基因的相对表达量恢复正常,说明在干旱胁迫条件下蒲公英通过增加渗透调节物质的积累,提高酶保护系统的活性来增强植株的抗逆性,上调质膜水孔蛋白基因的相对表达量来加强水分运输能力。     

一株产胶霉菌素菌株的ARTP诱变及筛选

试验旨在选育出胶霉菌素高产菌株,以胶霉菌素产生菌TY-009为初始菌株,利用常压室温等离子体(ARTP)诱变技术对产胶霉菌素的绿色木霉菌株进行诱变处理,并设置时间梯度,检测不同处理时间样品的胶霉菌素产量。通过平板筛选以及摇瓶复筛选出8株正突变菌株,其中产率最高达到0.86 mg/m L,较初始菌株的产率提高了45.76%。ARTP诱变方法快速、高效,对绿色木霉菌株的诱变效果良好,在提高胶霉菌素产量方面有很好的应用前景。     

等离子体脉冲荷电喷雾装置

设计了一套用于荷电喷雾的高压脉冲电源和等离子发生环 ,详细介绍了脉冲电源电路、电极结构和脉冲荷电喷雾系统 ,分析了脉冲电源的荷电原理 ,检测了系统的荷质比。理论分析和试验结果表明 :在同样试验条件下 ,脉冲电源优于普通直流高压电源 ,具有起晕电压低、能耗省、工作平稳、结构紧凑等特点 ,可靠、经济、实用     

Fat feeding increases equine heparin-released lipoprotein lipase activity

The aim of this study was to establish the dose-response relationship between fat intake and heparin-released plasma lipoprotein lipase (LPL) activity in horses. Eight mature trotters were fed 4 rations with different fat levels (3.0, 5.0, 7.7, or 10.8% fat in the dry matter) according to a 4 X 4 Latin square design. The experimental rations consisted of hay and different concentrates; the concentrates and hay were given in a 3:1 ratio on an energy basis. Soybean oil was added to the concentrates at the expense of isoenergetic amounts of glucose. Blood samples were taken at the end of each dietary period, which lasted 3 weeks. Fat feeding was found to increase heparin-released plasma LPL activity in a dose-dependent fashion. When the data from this study and previous studies were combined it was calculated that an increase in fat intake by 1 g/kg dry matter is associated with an increase in LPL activity by 0.98 micromol fatty acid released-mL(-1) x h(-1). Fat feeding raised the plasma concentrations of total cholesterol, high-density lipoprotein cholesterol, and phospholipids. Diet did not have a statistically significant effect on plasma triacylglycerol concentrations. The results are discussed in the light of the possible enhancing effect of fat feeding on the oxidative capacity of skeletal muscle.     

蛋用型鸡血浆极低密度脂蛋白浓度,肥度,生产性能之间的相关研究

以褐壳蛋鸡祖代母本种鸡为研究材料，用比浊法测定血浆极低密度脂蛋白浓度。试验结果表明，母鸡８１周龄腹脂重，腹脂率，鲜肝脂肪含量的变异系数分别高达４７％，３９％，４７％。表明这些性状在鸡群中未做过选择。血浆ＶＬＤＬ浓度与腹脂重，腹脂度，肝重，肝脂含量均呈正表型相关趋势。     

日粮能量和蛋白水平对肉鸡腹脂和血脂的影响

对７０８只（公、母各半）５～９周龄黄羽肉鸡进行３个代谢能水平（１３．４,１２．５,１１．６ＭＪ／ｋｇ）和３个粗蛋白水平（２２．４％,１９．４％,１６．４％）交叉的饲养试验,以探讨日粮代谢能和粗蛋白水平时黄羽肉鸡腹脂和血脂水平的影响。日粮代谢能和粗蛋白水平对腹脂有明显影响,腹脂随日粮代谢能水平的升高而升高（Ｐ＜０,０１）。随粗蛋白水平的升高而降低（Ｐ＜０．０５）。日粮能量和蛋白水平对板油的影响与腹脂相似。日粮代谢能水平对肌胃脂无明显影响;日粮粗蛋白水平对肌胃脂重无明显影响,但对肌胃脂率有一定影响（Ｐ＝０．０７）。日粮粗蛋白和代谢能水平对血浆极低密度脂蛋白（ＶＬＤＬ）、甘油三酯、胆固醇及总脂浓度均有显著影响（Ｐ＜８．０５）,８周龄血浆ＶＬＤＬ浓度随日粮代谢能的升高而降低（Ｐ＜０．０００１）;血浆总脂和胆固醇浓度均随日粮代谢能、粗蛋白水平的升高而降低（Ｐ≤０．００１）。肉鸡８周龄血浆ＶＬＤＬ水平明显存在日粮能量和蛋白的互作效应（Ｐ＜０．０１）,而血浆甘油三酯、胆固醇和总脂水平不存在明显的能量和蛋白的互作（Ｐ＞０．０５）。     

The combined effects of temperature and GnRHa treatment on the final stages of sexual maturation in Atlantic salmon (Salmo salar L.) females

Atlantic salmon (Salmo salar L.) females (2 SW), maturing for the first time, were reared under one of three temperature regimes (high: 14.3 ± 0.5°C; natural: 10.6 ± 1.0°C; and cold: 6.9 ± 1.0°C) in combination with one of two experimental treatments; an injection of GnRH analogue (GnRHa) contained in biodegradable microspheres, or a sham injection (microspheres only). The six experimental groups were then reared under simulated natural photoperiod for 4 weeks. Blood samples were drawn for analysis of plasma steroid levels and the fish were inspected for ovulation weekly. Batches of stripped eggs were incubated in triplicate incubators in raceways until the eyed stage. Treatment with GnRHa resulted in a substantial advancement and synchronization of ovulation at all temperatures, while exposure to cold water also appeared to advance ovulation slightly. While 75% (warm and cold) to 90% (natural) of GnRHa fish ovulated during the 4-week trial, only 30% of sham-treated females exposed to cold water, and none of the sham-treated fish held at higher temperatures, ovulated during this period. Survival rates of embryos to the eyed-stage were significantly higher for broodstock exposed to cold water. Plasma levels of testosterone (T), 17β-oestradiol (E₂), and 17α,20β-dihydroxy-4-pregnen-3-one (17,20βP) were all significantly affected by treatment with GnRHa and, to a lesser extent, temperature. The efficiency of GnRHa in counteracting the negative effects of high temperature on ovulation and the associated changes in circulating sex steroids suggest that temperature inhibition operates at least in part at the brain or pituitary.     

耐受自身代谢产物及耐二甲基亚砜红霉素高产菌株的选育

为提高红霉素发酵单位,考察了二甲基亚砜(DMSO)添加时间和体积分数对红霉素合成的影响,采用筛选自身代谢产物突变株的方法,将突变株进行常压室温等离子体(ARTP)诱变和耐受高浓度DMSO处理。结果显示,在36 h向发酵瓶中添加30000μg/m L红霉素,筛选得到化学效价比对照提高22.4%的菌株。DMSO最适添加时间为发酵48 h,最适添加剂量为0.2%,其可提高发酵单位10.1%。