水钾耦合对苜蓿根颈抗氧化特性及越冬率的影响

为探究不同水钾耦合处理对科尔沁沙地生境下种植苜蓿（Medicago sativa）抗寒生理特性的影响，以‘骑士T’和‘公农1号’苜蓿品种为试验材料，采用两因素裂区随机区组设计，水分处理为主区：灌水时间间隔分别为4 d，8 d和12 d（用W₁，W₂，W₃表示）；钾肥施用量水平为副区，具体施用量分别为50 kg·hm^-2 K₂O，100 kg·hm^-2 K₂O和150 kg·hm^-2K₂O（用K₁，K₂，K₃表示），并设置不施钾肥为对照（CK），于越冬前期挖取苜蓿根颈材料测定丙二醛（Malondialdehyde，MDA）、可溶性蛋白含量和抗氧化酶活性，翌年测定越冬率。结果表明：在W₃灌水时间间隔处理下，‘骑士T’和‘公农1号’品种苜蓿根颈的过氧化氢酶、过氧化物酶和超氧化物歧化酶活性、越冬率以及可溶性蛋白含量均明显高于W₁和W₂处理，其中以K₂施用量处理下的数值与CK差异最显著（P<0.05），且此施肥量下的MDA含量也显著低于CK（P<0.05）。因此在科尔沁沙地生境下生产苜蓿，灌水时间间隔为12 d、钾肥施用量在100 kg·hm^-2K₂O有利于提高苜蓿抗寒性。     

Identification of an H1N1 subtype of swine influenza virus and serological analysis

To investigate the epizootic of swine influenza virus(SIV), 60 nasal swabs were collected from a clinical cases of pig farm in Tai'an City, Shandong Province of China in April 2017. SIV was isolated by inoculating into 10-day-old Special Pathogen Free embryonated eggs and the whole genome was sequenced. An H1N1 subtype SIV was isolated and designated as A/swine/Shandong/TA04/2017(H1N1). Phylogenetic analysis showed that apart from the polymerase A(PA) fragment belonging to the 2009 pandemic H1N1 branch, seven genome segments belonged to avian-like H1N1 influenza virus lineage. The cleavage site sequence of the hemagglutinin(HA) protein was PSIQSR↓G, which is a typical molecular biological characteristic. Five potential N-glycosylation sites(N14, N26, N277, N484 and N543) were found in the HA gene. To further investigate the epidemiology of SIV in this farm, the 995 serum samples were assessed with EAH1N1 2009 pandemic H1N1 and H3 N2 antigens. The results showed that the total positive rate was 65.43%. The positive rates of single virus infection detected by EAH1N1, 2009 pdmH1N1 and H3 N2 for serum HI(Hemagglutination inhibition) were 48.35, 30.85 and 7.47%, respectively. The results showed that SIV in Shandong Province has been reassorted in some segments and the SIV-positive rate was high on the SIV outbreak farm. These data provide evidence of an epizootic of SIV.     

Effect of cyclophosphamide on proliferation and apoptosis of rat mesangial cells in vitro

AIM:To investigate the effect of cyclophosphamide(CTX) on proliferation and apoptosis of mesangial cells(GMC) of rat in vitro. METHODS:GMC proliferat ion was detected by MTT method,GMC apoptosis was examined by inverted microscopy for phase-contract and fluoroscopy and flow cytometry analysis.The levels of Fas and Bcl-2 were also detected by immunohistology. RESULTS:The proliferation of GMC were inhibited by CTX, methylprednisolone(MP), low molecular weight heparin(LMWH). Apoptosis of GMC was induced by CTX, the apoptosis rate of GMC was 8.2%, and the Fas level was increased. CONCLUSION:CTX could inhibit proliferation and induce apoptosis of GMC possibly by enhancing the Fas level.     

组氨醇脱氢酶抑制剂的研究动态

组氨醇脱氢酶(HDH)是组氨酸生物合成过程中最后两步反应的催化酶。对组氨醇脱氢酶的结构、催化机理、组氨醇脱氢酶抑制剂等方面的研究动态进行了较为详细的综述。     

1-(1-苯基-1,2,4-三氮唑-3-氧代乙酰氧基)烃基膦酸酯的合成与植物生长调节活性

合成了一系列新的1-(1-苯基-1, 2, 4-三氮唑-3-氧代乙酰氧基) 烃基膦酸酯, 并测定了它们对小麦和黄瓜的植物生长调节活性。结果表明, 在100 Lg/g 时, 所有化合物对小麦芽鞘的生长具有抑制作用, 而在10 Lg/g时化合物6a、6g 对黄瓜显示了较高的促生长活性。     

马杜霉素发酵法生产工艺的研究

马杜霉素是一种应用广泛的兽用抗球虫抗生素.以马杜霉拉放线菌(Actinomadura Yumanense sp.)ZU-M3为生产菌株,通过摇瓶实验获得较适宜的发酵条件:发酵培养基含葡萄糖7%,豆饼粉1.2%,玉米浆1.2%,NaCl 0.3%,CaCO3 0.1%,K2HPO3 0.03%,Fe2(SO4)3 0.01%,初始pH为6.6,发酵温度为34 ℃.用3L发酵罐做放大试验,通气速率为0.12 m3/h,搅拌速率600 r/min,发酵8 d 菌液发酵单位达到8 336 μg/mL.该研究结果对于大规模的工业化生产具有指导意义.     

禾本科小麦族三个物种的核型及进化关系分析

首次报道了禾本科小麦族3个物种的核型,二倍体长穗偃麦草2n=2x=14=10m 4sm(2SAT),核型属于2A型;假鹅观草2n=2x=14=8m 6sm(2SAT),核型属于2A型;中间偃麦草2n=6x=42=16m 20sm(4SAT) 6st,核型属于3B型;同时,根据Stebbins的核型进化理论和分支系统学的编序、赋值方法,对核型的4个重要性状进行了分析,结果表明在这3个物种中二倍体长穗偃麦草与假鹅观草进化程度基本一致,而中间偃麦草相对进化程度较高。     

沙地生境不同播期对紫花苜蓿生产性能及其越冬率的影响

为确定科尔沁沙地种植苜蓿（Medicago sativa）的适宜播期，本研究于2017年在内蒙古阿鲁科尔沁旗，选择骑士T、公农1号、擎天柱3个紫花苜蓿品种，7月1日开始播种，每5天播种1期，共10个播期，分析播期、生产性能、越冬率之间的关系。结果表明：建植当年苜蓿播种越晚干草产量越低，骑士T干草产量在7月21日播期显著降低（P<0.05），公农1号干草产量在7月16日播期显著降低（P<0.05），擎天柱干草产量在7月11日播期显著降低（P<0.05）；随播种时期的推迟，苜蓿株高、单枝条重呈降低的变化趋势，单位面积株数和枝条数呈先增加后降低的变化趋势；苜蓿越冬率从播期7月16日开始显著降低，公农1号在7月16日以前播种越冬率显著高于骑士T和擎天柱（P<0.05）；播种翌年第1茬苜蓿干草产量和株高随着播期的推迟而逐渐降低，2，3茬则无明显变化；苜蓿单位面积株数和枝条数都随播期的推迟呈降低的变化趋势，随着刈割茬次的增加，苜蓿的株数逐渐降低。因此，在科尔沁沙地种植紫花苜蓿最佳播期为7月1日—7月16日。     

绿色木霉Fn10-1纤维素酶的分离纯化及酶学特性测定

试验研究了绿色木霉Fn10-1纤维素酶的初步纯化及酶学性质开展研究。结果表明,该纤维素酶的最适催化温度为70℃,最适pH 7.6,在温度为4~50℃下均能保持较稳定的酶活,高于50℃以后,热稳定性变差,酶活力开始急剧下降。pH在5.6~7.6时该酶有较好的稳定性。Na+、Mn2+、Fe2+、Mg2+、Co2+、Ca2+、Ba2+、Al3+对纤维素酶具有一定的激活作用,Ag+、Fe3+、Cu2+、Zn2+、K+对该酶有一定的抑制作用,其中Cu2+的抑制作用尤为明显。