河北太行山区土地资源生态安全研究   总被引：10，自引：0，他引：10  

刘欣  葛京凤  冯现辉 《干旱区资源与环境》2007,21(5):68-74

本文在PSR模型的基础上,从土地自然资源现状、土地社会经济环境压力、人文响应三方面出发,选取与山区土地资源密切相关的27项因素构建指标体系,对河北太行山区土地资源生态安全进行评价。采用ArcView、ArcGis软件对河北太行山遥感图像进行处理,获取土地方面数据并结合其他统计数据,运用相关数学方法,计算研究区1987、2000年各县综合生态安全值,对生态安全状况进行安全度分区分析,研究认为,该区域土地资源生态安全状况处于较差状态,且局部有恶化趋势,进而剖析其主要制约因素,提出相应改善安全状况的建议。  相似文献   

人工清除流脂防治萧氏松茎象试验研究     

王新根  谢卫华  彭秀梅  唐艳龙  温小遂  唐学君 《江西植保》2007,30(4):194-196

研究了人工清除萧氏松茎象寄主流脂对其种群密度的影响,结果表明:该方法对萧氏松茎象的种群密度有明显的影响,试验区的有虫株率平均下降了37.2%,平均相对防治效果达49.1%。防治后试验区和对照区有虫株率差异极显著。  相似文献   

Biomass evaluation of concealed insect pests at parasitism based on allometric scaling laws     

Xiao-yi Wang  Yan-long Tang  Ji-fang Lu  Zhong-qi Yang 《Phytoparasitica》2013,41(4):435-441

In general, it is difficult to evaluate host resource utilization of parasitoids by examining the biomass of concealed wood borers at parasitism, because the larval tissues of parasitized hosts observed in field surveys are often almost completely consumed. This work explored a precise and convenient method for evaluating the biomass of concealed wood-boring insect pests after they are parasitized. Allometric scaling laws were used to determine mathematical relationships between larval weight and other size variables in two host insects: the emerald ash borer [EAB], Agrilus planipennis Fairmaire, and the oak long-horned beetle [OLB], Massicus raddei (Blessig). These insects are hosts of the parasitoid Sclerodermus pupariae Yang et Yao (Hymenoptera: Bethylidae). Our results showed that body weight among different instars was significantly different for both host species, with greater overlap between neighboring instars. Mean larval weight had a highly significant exponential relationship with instar number. EAB larval weight showed a highly significant power relationship to body length and width, width of the prothoracic plate, peristoma width, urogomphus length, and anteriormost width of the urogomphus. Significant power relationships were also observed between OLB larval weight and body size parameters (including body length, length of the mesothoracic spiracle, width of the prothoracic plate, distance between the main ocelli, and mandible length). These findings indicated that host biomass could be easily calculated if any one size variable could be measured at the time of parasitism. Allometric methods provide a precise means of evaluating time-specific biomass of concealed wood borers.  相似文献   

靶向S基因外源性microRNA抑制TGEV增殖效果的研究     

王龙涛  葛晨霞  王丹  陈立思  许蕤  胡静涛  李月红 《中国兽医学报》2015,35(6):873-876

应用生物信息学软件对猪传染性胃肠炎病毒(TGEV)S基因进行分析,筛选出可能与S基因有相互作用的外源miRNA:amiRNA-S-28035,amiRNA-S-28038,amiRNA-S-28165。之后,利用脂质体将构建好的相应的表达载体瞬时转染至PK-15细胞;通过Q-PCR和间接免疫荧光方法检测其对S基因的抑制作用;CPE分析和TCID50测定检测其对TGEV增殖的抑制效果。结果发现,3个外源性miRNA均降低了S基因mRNA的转录和蛋白的表达,其中amiRNA-S-28038对TGEV mRNA的平均抑制率可达64.6%,最高可达69.9%,表明外源性microRNA可以通过靶向TGEV基因组来抑制TGEV的复制。研究结果为猪传染性胃肠炎的预防和治疗提供了新的思路。  相似文献   

Jagged1 knocking down in endothelial cells accelerates PDGF induced proliferation and migration of vascular smooth muscle cells in rats     

WU Xiao-jing  HUANG Lan  ZHOU Qi  CHEN Jian-fei  ZHOU Yin-pin  NIU Qin  ZOU Yun-zeng  GE Jun-bo 《园艺学报》2009,25(10):1873-1877

AIM: To investigate the effect of Jagged1 expression in endothelial cells (EC) on platelet derived growth factor (PDGF) induced proliferation and migration of vascular smooth muscle cells (VSMC) in rat.METHODS: Rat aorta EC was inoculated in the lower chamber and VSMC were in the upper chamber of the cell coculture system. Three groups were divided: control, sicontrol and siJagged1. The EC Jagged1 protein expression was assayed by Western blotting to evaluate small RNA interfering (RNAi) efficiency. After the cells were cocultured with PDGF for 24 h, the proliferation and migration of VSMC were respectively evaluated by ［3H］-TdR incorporation and migrating cells counting. Protein expression of α-SM-actin in VSMC was assayed by Western blotting. RESULTS: The Jagged1 protein expression in EC was significantly lower in siJagged1 group than that in control group (0.26±0.02 vs 0.67±0.02, P<0.05), and no statistic significance was observed between control and sicontrol groups. The VSMC ［3H］-TdR incorporation and migration were higher in PDGF +siJagged1 group than those in PDGF group {［3H］-TdR incorporation (23 074±2 702) counts·min-1·well-1 vs (16 442±1 803)counts·min-1·well-1, n=5, P<0.05; migration (27±4) cells/field vs (15±3)cells/field, n=5, P<0.05}. The α-SM-actin protein in VSMC was lower in PDGF + siJagged1 group than that in PDGF group (0.25±0.06 vs 0.49±0.04, n=3, P<0.05).CONCLUSION: Jagged1 knock down in rat EC accelerates PDGF induced proliferation and migration of VSMC. These results suggest that Jagged1 expression in EC plays an important role in maintaining VSMC contract phenotype and inhibiting VSMC overgrowth after arterial injury.  相似文献   

不同培养基对肠球菌的检测效果比较     

鞠慧萍  石建华  苏粉良  葛晴颖  宋白薇 《农产品加工．学刊》2012,(1):109-110

肠球菌是食品、水、食品加工设备和食品生产环境等卫生状况的指示菌之一,对其进行检测的培养基种类较多。选用叠氮化钠葡萄糖肉汤和肠球菌肉汤对奶粉和水中肠球菌进行检测比较,结果表明,肠球菌肉汤具有绝对的优势,但在实际检测工作中,对不同样品进行检测时,应注意根据样品的性状合理选择培养基,以提高检测的速度和准确性。  相似文献   

中文数据库水产文献资源分析   总被引：3，自引：2，他引：1  

葛常水  欧阳海鹰  杨宁生 《农业图书情报学刊》2004,15(1):89-93

本文对我国 3个主要中文数据库文献资源以及水产文献收录量进行了统计分析。中国水产科学研究院信息研究中心开发的中国水产文献数据库目前共有记录 5 7196条 ,起始于 1983年。重庆维普资讯有限公司开发研制的中文科技期刊数据库中收录水产类记录 394 4 4条 ,清华同方公司的中国学术期刊光盘数据库收录水产类记录 3592 7条。中国水产文献数据库收录的水产文献量及时间跨度最大 ,是获取水产文献信息的首选数据库。维普库和同方库同样是我国重要的水产文献信息源。这三个数据库在水产文献信息服务中发挥了重要作用。虽然三库存在一定程度的交叉重复 ,但也存在着不同程度的互补性 ,并且在收录期刊和文献方面各具特色  相似文献   

马褂木等3个树种人工林生长量及生物量调查研究   总被引：2，自引：0，他引：2  

葛永金  练发良  王军峰  雷珍  柳新红  张健  严国琴 《浙江林业科技》2009,29(4)

对丽水市白云山人工林群落设置标准样地进行生长量和生物量调查.林分径阶分析显示,20年生马褂木(Liriodendron chinense)和24年生福建柏(Fokienia hodginsii)径阶集中在14～18 cm,径阶分布较集中,22年生日本冷杉(Abies firma)径阶具明显的双峰结构,林分总蓄积为马褂木(347.62 m3/hm2)>日本冷杉(175.31 m3/hm2)>福建柏(127.79 m3/hm2);连年生长量分析表明,马褂木胸径的连年生长高峰在第8～12年,在第10年达到最高峰,福建柏分别在第12年和第16年出现2个生长高峰,马褂木前期生长速度明显高于其他2个树种,但之后生长速度下降较快.马褂木人工林生物量比福建柏人工林高176.61%、比日本冷杉人工林高42.15%.在各人工林乔木层总生物量中,干材(包括树皮)最大,其中尤以马褂木干材比重最大,为68.43%,对以收获木材为主要经营目标的人工林来说,马褂木相对于福建柏和日本冷杉,具有较大的木材收益.  相似文献   

Development sategies on Gining agricultural mechanization     

QIU Hai-long  GE Shuang-qi  JI Gui-qiang 《湖南农机》2008,35(11)

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黄瓜果实曲直性评价方法及相关性分析   总被引：2，自引：0，他引：2  

葛长军  秦智伟  周秀艳 《中国蔬菜》2009,1(8):28-31

以48份黄瓜品种为试材，采用刨分法测量其果实弯曲度，通过黄瓜果实形态指标和相关分析可知弯曲度与果长、果柄长、果柄长/果长、果长/果横径显著正相关，与种腔大小、种腔/果横径极显著负相关，与果横径显著负相关，与果肉厚不相关。依据果形指数和弯曲度对黄瓜进行了分级。筛选出顺直品种8份，次弯曲品种9份，弯曲品种31份。  相似文献