北沙柳研究进展

北沙柳属杨柳科柳属植物,具有萌蘖力强,耐旱、耐盐碱和抗风沙的特点,是中国西北地区固沙造林的主要树种之一,兼具生态效益、经济效益和社会效益。我们综述了国内外近年来北沙柳的相关研究成果包括生长繁殖、生理生态特征、与真菌共生作用、防风固沙、分子生物学及产业化开发与利用,并对未来发展前景做出展望,提出优良种质资源收集、分子定向育种和资源合理开发等建议,旨在为北沙柳的种质资源库管理、资源保护和合理开发应用提供科学依据。     

进口棉花数字化样品标识系统的建立

针对进口棉花到货时间相对集中、检测工作量大、检验人员和仪器设备配置相对不足的现状,开发了进口棉花数字化样品标识系统。本文介绍了该系统的开发背景、硬件构成、系统架构和数据库管理设计,分析了其取代纸质抄录样品标识的优势,如通过实现样品标识信息传递自动化、检验数据传递及其处理的自动化提升工作效率。     

濒危中华鲟人工群体的繁殖生物学

以1998―2008年孵出的子一代(F1)中华鲟(Acipensersinensis)为材料,研究了人工养殖中华鲟的繁殖生物学特征。结果表明:年龄10～20龄的492尾人工养殖子一代中华鲟体重为30～169 kg,体长为140～258 cm,肥满度为0.77～1.26,体长(L)与体重(W)之间的关系式为W=1×10~(–5)L~(2.9658) (R~2=0.9076,n=492)。74尾中华鲟性腺发育成熟,成熟比例为15.04%,成熟个体中雄鱼体重[(60.73±14.53)kg]和体长[(172.27±13.46)cm]均小于雌鱼体重[(88.39±29.14)kg]和体长[(193.37±18.90) cm];雄鱼最小性成熟年龄为10龄,平均为(14.96±1.93)龄,雌鱼最小成熟年龄为12龄,平均为(17.84±1.80)龄。雄鱼催产成功率为76.36%,精子快速运动时间为(49.11±13.38) s,精子寿命为(220.75±56.47)s;雌鱼催产成功率为57.89%,产卵量为(13.43±6.79)万粒,卵径(3.97±0.15)mm,卵重(0.046±0.013)g,受精率为(42.72±27.82)%,孵化率为(51.61±32.41)%,出苗量为(4.44±5.67)万尾。与野生中华鲟相比,人工养殖中华鲟成熟个体体格、繁殖力和繁殖效果均有下降趋势,人工保种面临挑战。     

基于无人机多光谱遥感的夏玉米冠层叶绿素含量估计

为探讨利用无人机多光谱遥感影像监测夏玉米冠层叶绿素含量的可行性,基于2019年不同施氮水平下(0,105,210,315 kg·N/hm²)夏玉米多光谱遥感影像和田间实测冠层叶绿素含量数据,分析了不同施氮水平下夏玉米冠层叶绿素含量的变化规律,同时选取10种常用光谱植被指数与实测冠层叶绿素含量进行相关性分析,采用与实测叶绿素含量极显著相关的9种植被指数,构建了基于遥感光谱指数的夏玉米冠层叶绿素含量遥感监测模型,并通过精度检验确定最优估测模型.结果表明,施用氮肥能够提高夏玉米冠层叶绿素含量,过量氮肥不能持续提高叶绿素含量,同一施氮水平下不同追肥处理之间叶绿素含量没有明显差异.绿色归一化植被指数与叶绿素含量的相关性系数最高,达到了0.892.采用逐步回归分析方法建立的模型表现最优,决定系数为0.87,均方根误差及相对误差分别为0.15和2.68%.因此,无人机多光谱遥感结合逐步回归模型可以实现田间尺度的夏玉米冠层叶绿素含量的实时监测.     

黑麦草叶蛋白提取工艺研究

采用酸化和加热相结合的方法，研究了从黑麦草中提取叶蛋白的最佳工艺条件，并分析了黑麦草叶蛋白中的氨基酸组成。结果表明黑麦草叶蛋白提取的最佳工艺条件为pH4.0，料水比1：2，凝聚温度为70℃，加热时间5min。该条件下提取的叶蛋白含量可高达70.48%。氨基酸分析显示黑麦草叶蛋白中人体必需氨基酸、鲜味氨基酸和药效氨基酸分别占总氨基酸的40.3247%、22.2439%和77.5609%。黑麦草叶蛋白具有很好的营养、保健和药用价值。     

Role of PKC and MMPs in the pathogenesis of the rat experimental atherosclerosis and the action of Danshen injection

AIM: To study the effects of protein kinase C on the expression of MMPs that may play an important role in the formation of atherosclerosis and the possible mechanism of Danshen injection to treat atherosclerosis. METHODS: 50 Sprgue-Dawley (SD) rats were divided into three groups randomly: control group (group C), model group (group M) and Denshen treatment group (group D). The serum was collected to measure the level of cholesterol, triglyceride, low density lipoprotein cholesterol（LDL-ch）. The expression of PKC and MMPs were measured by immunohistochemistry. Light microscope and electron microscope were also used. RESULTS: ① The cholesterol, triglyceride, LDL-ch concentrations in group M and group D were significantly higher than those in group C (P<0.01), cholesterol, triglycerideand LDL-ch contents were lower in group D than group M (P<0.01). ② The expression of PKC, MMP-2, MMP-9 in group M were significantly higher than those in group C (P<0.01), and were significantly lower in group D than those in group M (P<0.01). The expression of PKC was correlated with MMP-2 and MMP-9. ③ Light microscope showed that there were plaques in intima and serious calcification, necrosis, obviously irregular thickness in media of group M, but slightly in group D. ④ Electron microscope showed that smooth muscle cells of group M were necrosed , collage grew abundantly and alined disorderly, most of the endothelial cells exfoliated, but slightly in group D. CONCLUSIONS: ① MMPs play an important role in the generation and development of atherosclerosis. ② The activation of PKC may take part in the formation of atherosclerosis and it may be the upstream mechanism of the expression of MMPs. ③ The reduced expression of MMPs and PKC is a part of mechanism for Danshen to prevent and treat atherosclerosis.     

Role of neutrophil elastase and myeloperoxidase in asthma of rats

AIM:To observe the changes of polymorphonuclear leukocytes (PMN), neutrophil elastase (NE) and myeloperoxidase (MPO) expression in rat asthma. METHODS:Eighteen rats were randomly divided into two groups on average, including asthma group and control group. The rat model of asthma was established by the ovalbumin (OVA) challenge methods. Blood PMN were isolated andpurified. The protein expression of MPO were detected by immunohistochemistry and chromatometry techniques. NE was detected by ELISA. RESULTS:(1) Immunohistochemistry showed that the levels of MPO expression around bronchus and in purified PMN in asthma group were significantly increased compared with those in control group (P<0.01). Activities of MPO were significantly increased in bronchoalveolar lavage fluid (BALF) and lung tissue in asthma group compared with those in control group (P<0.05, P<0.01). (2) Levels of NE were significantly increased in BALF and PMN in asthma group compared with control group (P<0.01). (3) Number of PMN were significantly higher in BALF, bronchus and lung tissue in asthma group than those in control group (P<0.01). CONCLUSION:Levels of PMN counting and expression of MPO and NEare significantly increased in experimental asthma rats. PMN may be involved in inflammation in asthma via increasing the levels of NE and MPO.     

应用荧光定量PCR对细粒棘球绦虫miRNAs在虫体不同发育阶段表达量的研究

为确定通过Solexa高通量测序鉴定出的大量细粒棘球绦虫miRNAs序列在不同生活史阶段的表达量。采用SYBR染料法和Race试剂盒相结合的荧光定量方法对原头节和生发层阶段的miRNAs表达进行了检测分析。结果表明：两阶段miRNAs表达差异较大,其中mir-71、mir-7、mir-1和mir-19在生发层阶段表达量较高,而let-7则在原头节阶段表达较高。说明这些miRNAs可能在细粒棘球绦虫发育阶段的基因转录调控中起着重要作用。     

铁元素对农田人参丙二醛含量及防御酶活性的影响

[目的]研究Fe2＋对人参（Panax ginseng Meyer）叶中防御酶活性和丙二醛（MDA）含量的影响。[方法]采用叶面供Fe2＋的方法。试验共设5个处理,Fe2＋浓度分别为：0（对照）、0.005%、0.050%、0.500%、2.000%。[结果]随着供Fe2＋水平的升高,MDA含量先降低后升高,过氧化物酶（POD）活性呈持续上升趋势,过氧化氢酶（CAT）活性先升高后降低,超氧化物歧化酶（SOD）活性呈先升高后降低再升高的趋势。[结论]从生理角度揭示了铁元素在人参生长发育中的作用机理,为人参的合理施肥提供理论参考。