煤矸石山植被恢复影响因子初探——以山西省阳泉市280煤矸石山为例

对山西省阳泉市280煤矸石山小气候特征、地形条件、煤矸石理化性质、水分和生物特点进行了调查分析.结果表明.煤矸石山的小气候特征表现为以干热和干旱为主.煤矸石自燃致使地温产生较大异常,局部自燃的煤矸石坡面地表温度远高于植物生长的正常温度范围.煤矸石山坡度大,堆积松散,易产生坡面侵蚀.表层煤矸石经侵蚀后,植被根系周围缺乏附着物,生长势逐渐变弱.煤矸石物理特性与黄土相比,其持水能力差,有效水分含量低,缺乏下层水分补给,直接影响到植物正常生长.自燃后的煤矸石pH值降低,表层煤矸石养分状况差,微生物种类和数量均偏少.煤矸石山植物生长状况显示,地表温度、侵蚀状况、酸性和含水量是影响植物生长的重要因子.地温高于50 ℃或pH值小于5的地区植物均不能生长.植物盖度在含水量小于15%的区域较含水量为20%的区域下降约10%～20%.在侵蚀区植物盖度下降约30%.     

断奶对仔猪肠道屏障的影响及营养调控

在集约化养殖中,3~4周龄早期断奶是仔猪生命周期中一个非常紧张的时期,此时仔猪胃肠道还未发育成熟。肠道屏障由上皮、免疫和肠神经系统组成,这些系统控制上皮屏障的完整性以及肠道功能,包括肠腔营养物质、水和电解质的运输。早期断奶导致肠道通透性增加,出现胃肠功能紊乱的情况,可能对猪只一生产生长期的影响。因此,仔猪断奶饲粮需要正确水平的营养素、营养源和高质量的添加剂,鼓励仔猪快速进食,减轻或消除断奶应激综合症,降低死亡率和发病率。养猪就是养"肠道",合理使用功能性氨基酸、植物化学物质和有机酸等添加剂,能够修复由于断奶应激综合症导致的肠道屏障功能障碍。     

Effect of Plasticizers on Properties of Rice Straw Fiber Film

In order to improve the properties of rice straw fiber film, one factor contrast test method was employed. Plasticizer type was chosen as input variable, dry tension strength and elongation, wet tension strength and elongation, bursting strength and tearing strength were chosen as indexes. The results showed that there were significant differences among the means of dry tension strength, dry elongation and bursting strength of different plasticizers; there were not significant differences among the means of wet tension strength, wet elongation and tearing strength of different plasticizers; for dry tension strength and elongation, glycerol had a significant difference with sorbitol and PEG, no significant difference was observed between sorbitol and PEG, dry tension strength added glycerol had been reduced 6.8% compared with that added sorbitol, reduced 9.5% compared with that added PEG; elongation had been improved 6.1% and 9.4%, respectively; for bursting strength, sorbitol had a significant difference with glycerol and PEG, no significant difference was observed between glycerol and PEG; bursting strength added glycerol and added PEG had been improved 6.9% and 5.6%, respectively compared with that of the added sorbitol. The results provided a theoretical reference for further improving the straw fiber film manufacturing process.     

金黄色葡萄球菌对奶牛乳腺上皮细胞Wnt/β-catenin信号通路和相关修复因子的影响

采用金黄色葡萄球菌侵袭原代奶牛乳腺上皮细胞,观察该病原菌对乳腺上皮细胞Wnt/β-catenin信号通路关键蛋白和相关修复因子EGFR、TGF-β3和VEGF基因mRNA表达的影响。金黄色葡萄球菌以MOI=1∶1的比例接种奶牛乳腺上皮细胞,分别作用0,15,30,45,60,120,240 min,采用Western blot法检测乳腺上皮细胞β-catenin、Cyclin D1及c-Myc蛋白表达水平;免疫荧光法检测β-catenin的表达及核易位;荧光定量PCR检测EGFR、TGF-β3和VEGF基因mRNA表达。结果显示,β-catenin蛋白在45,60,120 min表达量升高,与0 min相比差异显著(P<0.05);Cyclin D1蛋白在45,60,120和240 min表达量升高,差异显著或极显著(P<0.05或P<0.01);c-Myc蛋白在15,30,60,120,240 min表达量升高,差异极显著(P<0.01)。修复相关因子EGFR、TGF-β3和VEGF基因mRNA的表达量在30 min均出现极显著升高(P<0.01),且VEGF基因mRNA在45,60,120和240 min均呈现极显著升高(P<0.01),EGFR基因mRNA表达量在30,45和60 min时表达量极显著升高(P<0.01)。结果表明,金黄色葡萄球菌侵袭奶牛乳腺上皮细胞后,诱导Wnt/β-catenin信号通路的转导和修复因子EGFR、TGF-β3和VEGF基因转录,该信号通路和修复因子可能参与金黄色葡萄球菌导致的炎症和细胞损伤的修复过程。     

基因2型牛病毒性腹泻病毒RT-PCR检测方法的建立和初步应用

根据已发表的牛病毒性腹泻病毒基因1型(BVDV-1)和2型(BVDV-2)5非编码区(5-UTR)的序列,分别设计了针对BVDV-1型、BVDV-2型以及针对BVDV-1和BVDV-2两型的特异性引物和通用引物,以标准参考株BVDV-1 NADL株和BVDV-2890 株为对照,建立了分别能检测BVDV-1、BVDV-2和BVDV-1/BVDV-2的RT-PCR 检测方法.在此基础上,进一步对疑似BVDV-2感染牛的临床病料组织(脾、淋巴结、心肌、血液等)检测结果表明,在所检测的18份样品中,BVDV-2阳性8份(44%).经RT-PCR鉴定为阳性的组织病料,进一步通过MDBK 细胞进行病毒分离,病毒分离率为100%;结合感染细胞病变观察,间接免疫荧光试验RT-PCR和序列测定鉴定,所分离的病毒均为BVDV-2.上述研究表明,该RT-PCR检测方法敏感、特异;并证实我国牛群已存在BVDV-2的污染或感染.     

南宁市双色中华蜜蜂探析

近几年来,南宁的许多中华蜜蜂(以下简称中蜂)养殖场经常出现麻色蜜蜂和黄色蜜蜂混同一起的种群(简称双色群),引起中蜂养殖者的高度关注。笔者在南宁市吴圩镇(广西国有七坡林场)定地养殖中蜂十余年,每年都有少量双色蜂种群出现,为此对双色中华蜜蜂进行了详细观察、记录、验证,认为双色蜂不是一个独立品种,是外来黄色蜂种与本地麻色蜂种杂交的结果。     

基于形态数据的大白菜核心种质构建方法的研究

 以国家蔬菜种质资源中期库收集保存的1 651份大白菜种质为试材,按照大白菜分类系统和生态型,采用分层分组法,将所有种质分为6组。基于43个形态性状的数据,比较了4种组内取样比例法、6种总体取样规模和2种取样方法在构建大白菜核心种质中的作用和效果。结果表明：组内以多样性比例法更能使各组的取样份数或比例趋于平衡,并较好地保持原始收集品的变异度。当总体取样规模为15%时,多样性比例法所构建的核心种质的遗传多样性指数达到最大,表型保留比例亦能达到98％左右;而当总体取样规模增加到20%以上时,虽然表型保留比例接近100％,但核心种质遗传多样性指数迅速降低。因此,认为15%总体取样规模较为合适。在一定的组内取样比例法和总体取样规模下,聚类取样构建的核心种质的遗传多样性指数（I）、表型保留比例（RPR）和变异系数（CV）均比随机取样的高。根据获得的优化方案最终在表型水平建立了包含248份种质的中国大白菜核心种质。     

Involvement of extracellular signal regulated kinase in the regulation of amyloid precursor protein processing in PC12 cells by TPPB

AIM: To explore the signal transduction pathways involved in the regulation of amyloid precursor protein (APP) processing by protein kinase C (PKC) activator TPPB.METHODS: PC12 cells were treated with TPPB (PKC activator) for 3 h and various signal transduction inhibitors were added to the conditioned medium to investigate their effects on α-secretase form of soluble amyloid precursor protein (sAPPα) secretion after TPPB treatment via Western blotting. Extracellular signal regulated kinase (ERK, p42/44MAPK) and phospho-p42/44MAPK were also measured after TPPB treatment.RESULTS: TPPB (1 μmol/L) significantly increased sAPPα secretion as compared with control group. The increase in sAPPα secretion by TPPB was partially blocked by ERK inhibitor U0126, c-Jun N-terminal kinase (JNK) inhibitor SP600125 and protein tyrosine kinase (PTK) inhibitor genistein, but not by p38MAPK inhibitor SB203580. TPPB (1 μmol/L) increased the expression of phospho-p42/44MAPK without altering total p42/44MAPK levels.CONCLUSION: ERK, JNK and PTK may be involved in the regulation of APP processing by TPPB.     

返青期醉马草株体对几种牧草种子萌发的化感作用

以采自新疆天山北坡的醉马草(Achnatherum inebrians)株体为供体植物,红豆草(Onobrychis viciaefolia)、紫花苜蓿(Medicago sativa)、无芒雀麦(Bromus inermis)3种补播牧草及醉马草自身为受体植物,采用培养皿滤纸法研究返青期醉马草不同营养器官水浸液在0.2、0.1、0.05和0.025g·mL-1 4个浓度下对这4种植物种子萌发的化感作用。结果表明,醉马草株体水浸液对4种植物种子的化感作用均表现为抑制作用,且敏感性从强到弱依次为醉马草无芒雀麦红豆草紫花苜蓿;不同部位的醉马草水浸液化感作用强度为茎叶根;醉马草株体水浸液对紫花苜蓿种子的萌发具有低浓度(0.025g·mL-1)促进、高浓度(0.2g·mL-1)抑制的作用,而对无芒雀麦、红豆草和醉马草种子,则不同浓度呈现出不同程度的抑制效应。因此,建议使用紫花苜蓿等耐受性较好的牧草来对醉马草爆发区进行春季补播恢复。     

斯氏线虫感染双钩异翅长蠹的致死中量与致死中时间

在室内测定了斯氏线虫对进境原木上的检疫性害虫——双钩异翅长蠢的致死中量和致死中时间,旨在为大规模应用斯氏线虫检疫处理双钩异翅长蠢提供理论依据。将TDM模型引入试验结果的分析中,得出了双钩异翅长蠢幼虫和蛹的TDM模型以及LD50与LT50。72h后双钩异翅长蠢老幼虫的TDM模型为：Pij=1-exp[-3.0514 2．02721g(di)],LD50为1．3244(条线虫／头),LT50为1．2385d。试验结果表明：随着时间的延长,LD50都逐渐减少,这是因为随着时间的延长,增加了斯氏线虫与双钩异翅长蠢接触的机会;随着线虫剂量的增加,LT50逐渐减少,即线虫剂量增加,幼虫死亡50％所需的时间就少。