奶牛乳房炎诊断技术的研究进展

奶牛乳房炎是影响奶牛生产的主要疾病之一。病原菌的免疫抑制以及日趋严重的耐药性,致使乳房炎的发病率增高且治愈困难,给世界奶牛养殖业造成了巨大的经济损失。实践表明,疾病的诊断是疾病病因和治疗之间最重要的一步。经济、快速、可靠的诊断工具是乳房健康管理的基础。本文主要论述了奶牛乳房炎不同诊断方法的优缺点以及新兴诊断技术的研究进展。     

莲腐败病菌遗传转化体系的构建

由共享镰刀菌Fusarium commune引起的莲腐败病是我国莲生产上的主要病害之一。本研究以强致病力菌株FCN23为供试菌株,通过PEG介导的遗传转化法研究了菌龄、酶解时间和渗透压稳定剂等对原生质体制备的影响。结果表明,分生孢子在YPD液体培养基培养24 h获得新鲜菌丝,在酶解时间为2.5 h,渗透压稳定剂为0.7 mol/L NaCl溶液时原生质体制备效率最高。进而将遗传霉素的抗性基因和绿色荧光蛋白基因转入莲腐败病菌原生质体中,获得了稳定表达的转化子,能够稳定遗传gfp基因,说明莲腐败病菌的遗传转化体系构建成功。该体系的建立为莲腐败病菌的侵染过程及基因功能研究奠定了基础。     

化学预处理对稻草硅化程度的影响及其对瘤胃降解率的改善效果

本试验结合化学分析与电镜技术,探讨了氨化与碱化处理对稻草硅化程度的影响,分析了稻草硅化程度与降解率的相关性。化学分析显示,碱化或氨化处理稻草的总硅含量随氢氧化钠或碳酸氢铵处理剂量的增加而线性下降(P<0.01);可溶性硅含量随碳酸氢铵处理剂量的增加变化不显著(P>0.05),但随氢氧化钠处理剂量增加线性下降(P<0.01);总硅与稻草干物质降解率间存在极显著负相关(r=-0.560,P<0.01)。电镜观察发现,氢氧化钠处理的稻草茎表皮根毛皱缩、乳突和瘤状结构部分溶解,碳酸氢铵处理的稻草茎外表皮层部分脱落;氢氧化钠处理的稻草茎表皮有明显的降解优势,碳酸氢铵处理的稻草茎表皮瘤胃降解72h后仍保持完整的乳突和瘤状结构。上述结果表明,氨化和碱化处理可以在一定程度上降低稻草的硅化程度,借此提高稻草的降解率,但两者降低稻草硅化的程度与方式不同。氨化处理通过使稻草表皮层部分脱落,降低稻草总硅含量,但借此提高稻草降解率的作用较弱;碱化处理可使稻草表皮硅酸盐部分溶解,从而使稻草总硅含量、可溶性硅含量下降,加速稻草降解。     

互联网对军校思想政治工作的负面影响及对策

互联网在给整个社会带来了前所未有变革的同时,也给军校思想政治工作带来负面影响和严峻挑战。在新形势下,我们应高度重视和充分利用信息网络技术,积极研究网络环境下思政工作的对策,扬长避短,提高思政工作的效力。     

番茄S-腺苷蛋氨酸脱羧酶基因SlSAMDC1的克隆与序列分析

 以蔓陀罗S-腺苷蛋氨酸脱羧酶全长cDNA序列为信息探针, 筛选NCBI番茄EST数据库, 依据同源EST信息,经人工拼接、RT-PCR及RACE技术验证,获得了1个新的SAMDC基因家族成员,命名为SlSAMDC1(GenBank登录号：EF550528),并利用染色体步移技术克隆了879 bp的上游调控区域。SlSAMDC1 cDNA序列全长1 847 bp, 5′-UTR和3′-UTR分别长523 bp、241 bp;存在3个ORF(微型uORF、小型uORF和主ORF),主ORF编码360个氨基酸的SAMDC酶原;SlSAMDC1基因组序列全长3 648 bp,有3个内含子,均位于5′-UTR,所有内含子的剪切位点均符合真核生物“GT-AG”规则。SlSAMDC1基因与其它植物来源SAMDC基因同源性较高,与人、大肠杆菌以及酵母的同源性较低。表达谱分析发现,SlSAMDC1基因在番茄根、茎、叶、花蕾、果实等器官中均表达,果实中的表达量相对较高。生物信息学分析表明,SlSMDC1基因的上游调控序列存在多个顺式作用元件,如W-box、TATA-box、CAAT-box等。     

Protective effect of Jumi extraction on hearts of ischemia-reperfusion injury in rat

AIM: To examine the effect of Jumi (JM) extraction on the contraction of hearts and its cardiac protection against ischemia-reperfusion injury.METHODS: Cardiac contractility and infarct area were analyzed by the Langendorff method in isolated rat hearts.RESULTS: (1) After perfusion with JM extraction (0.5,1.0,2.0 g/L),LVDP,±dp/dtmax and coronary flow were enhanced.(2) JM extraction increased myocardium nitric oxide synthase (NOS) activity and nitric oxide (NO) content in a concentration-dependent manner.(3) Preconditioning or postconditioning of the heart with JM extraction (0.5 g/L),both provided cardioprotection as evidence by improving postischemic ventricular functional recovery and reduced myocardial infarct size.Preperfusion of the hearts with L-NAME (a NOS inhibitor) abolished the cardioprotection induced by JM extraction preconditioning or postconditioning.CONCLUSION: The results demonstrate that JM extraction has positive effect in isolated rat hearts,and it can protect rat heart against ischemia-reperfusion injury through a NO-dependent pathway.     

Effects of Tian ma gou teng decoction on the serum free calcium concentration and the L-type calcium channels in the vascular smooth muscle cells in spontaneously hypertensive rats

AIM: The research was to investigate the effects of the Tian ma gou teng decoction on the electric physiology feature of L-type calcium channels in the vascular smooth muscle cells in spontaneously hypertensive rats (SHR), and to further explain the mechanism of the Tian ma gou teng decoction in the intervention of blood pressure.METHODS: 12-week-old SHRs were assigned randomly into five groups：group A (treated with Tian ma gou teng decoction), group B (treated with Tian ma gou teng decoction with subtraction concha haliotidis), group C (treated with nifedipine), group D (treated with concha haliotidis), group E (treated with normal saline as control), each group consisted of 9 rats. After treatments were conducted for 4 weeks, the free calcium concentration in serum was measured. The electric physiology feature of L-type calcium channels in the vascular smooth muscle cells was analyzed by patch clamp technique (PCT).RESULTS: No significant difference between group A and group C was observed in the serum free calcium concentration (P>0.05). There were significant differences among group B, group D and group E (P<0.05), compared to before treatment, the change in group E was the most obvious. A decrease in the L-type calcium channel current of vascular smooth muscle cells was observed in group A and group C. The function of group D was feeble, no decrease in the L-type calcium channels current of vascular smooth muscle cells was observed in group B and group E.CONCLUSION: Tian ma gou teng decoction can increase the serum free calcium concentration and block the L-type calcium channel current in vascular smooth muscle cells, indicating one of the mechanism of intervention of blood pressure.     

Clinical significance of elevated serum interleukin 15 in patients with active lupus nephritis

AIM: To detect interleukin 15 (IL-15) levels in peripheral blood from patients with active lupus nephritis and investigate its clinical significance. METHODS: IL-15 level was determined by enzyme linked immunosorbent assay (ELISA). The peripheral blood mononuclear cells (PBMCs) were isolated with grads density abaxiality. The inhibitory effects of dexamethasone on production of IL-15, IgG and anti-dsDNA antibody in cultured PBMCs from LN patients were also investigated. RESULTS: (1) Serum IL-15 level in LN patients was significantly higher than that in normal controls (P<0.01). Serum IL-15 level in active LN patients was significantly higher than that in remised patients (P<0.05). (2) Serum IL-15 level was positively correlated with SLEDAI, anti-dsDNA antibody and 24 h urine protein excretion in active LN patients. (3) Serum IL-15 level was significantly reduced in LN patients treated with combination of cyclophosphamide (CTX) and steroid for 12 weeks. (4) Secretion of IL-15, IgG and dsDNA antibody in cultured PBMCs from active LN patients was significantly higher than that in normal control group, and IL-15 level in supernatant of cultured PBMCs from active LN patients was positively correlated with IgG and dsDNA antibody. Dexamethasone inhibited the secretion of IL-15, IgG and dsDNA antibody in cultured PBMCs from LN patients. CONCLUSION: Serum IL-15 level in patients with active lupus nephritis is significantly elevated, suggesting that IL-15 may be involved in the pathophysiological process of LN. IL-15 may be used as an index to assess the activity of LN.     

早熟丰产苦瓜长丰3号的选育

长丰3号苦瓜是汕头市白沙蔬菜原种研究所用C99-01A作母本、C01-03B作父本配制而成的杂交一代组合。果实长圆锥形,瓜长25～30cm,横径6～8cm,皮绿色,单瓜质量300～600g。中抗白粉病、枯萎病,耐热、耐寒、耐涝性强,适应性广。早熟,播种至初收春季为75天,夏秋直播后52天始收,每667m2产量3000～4000kg。     

畜禽有机复合肥对瓜类作物产量与品质的影响

研究了畜禽有机复合肥对瓜类作物产量与品质的影响。试验结果表明,基施嘉宝牌畜禽有机复合肥3.0～7.5t/hm2,瓜类作物收获后土壤速效K含量比CK增加155.59%～193.48%,同时显著提高了黄瓜的株高、茎粗、叶片数、功能叶面积和坐果率;黄瓜、西瓜和甜瓜产量随着有机复合肥施用量增加而增产,增幅为9.19%～27.16%,且黄瓜增产最为显著,黄瓜、西瓜和甜瓜的单位面积最佳经济施用量分别为7.5t/hm2、3.0t/hm2和4.5t/hm2;有机复合肥能提高黄瓜VC含量和西甜瓜中心糖度,显著改善其商品性和产品品质。