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71.
接种不同AM真菌对滇重楼幼苗功能基因表达的影响 总被引:1,自引:0,他引:1
为探究接种不同外源性从枝菌根(Arbuscular mycorrhizae,AM)真菌对滇重楼幼苗基因表达的影响,本研究以灭菌土壤为生长基质,将滇重楼(Paris polyphylla var. yunnanensis)新鲜种子与28种AM真菌于室温盆栽条件下共培养,采用实时荧光定量PCR的方法检测鲨烯环氧酶基因(Squalene epoxidase,SE)、共生受体类似激酶基因(Symbiosis-receptor-like kinase,SYMRK)、产生钙离子振荡的通道蛋白基因(Doesn’t making fections 1,DMI1)、钙/钙调依赖性蛋白激酶基因(Calcium/calmodulin-dependent protein kinase,CCa MK)4个功能基因在滇重楼幼苗的差异表达情况。结果表明:28株AM菌株可不同程度的影响SE、SYMRK、DMI1、CCa MK 4个功能基因的表达,其中薄壁两性囊霉(Ambisporaleptoticha,Ale)和崔氏原囊霉(Archaeospora trappei,Atr)可以显著增加4个功能基因的表达量。隐类球囊霉(Paraglo-mus occultum,Po)和透明盾巨孢囊霉(Scutellospora pellucida,Spe)可以增加SE、SYMRK的表达,细凹无梗囊霉(Acau-lospora scrobiculata,Asc),亮色盾巨孢囊霉(Racocetra fulgida,Rfu),哥伦比亚内养囊霉(Entrophospora colombiana,Ec),明球囊霉(Rhizophagus clarus,Rcl),根内球囊霉(Rhizophagus intraradices,Rin)可以增加DMI1的表达。综上所述,接种的28株AM真菌菌株中Ale和Atr能显著的提高4种功能基因的表达,结合前期与滇重楼无菌播种幼苗进行共生培养分析AM真菌对种子萌发及幼苗化学成分的影响,推测这两株菌可望能作为培育滇重楼菌根化苗的理想菌株,人工接种AM真菌可为保护和提高滇重楼开辟了一条新的途径。 相似文献
72.
Peck Shen Mun Hua Nong Ting Teng Aik Ong Chew Ming Wong Kwan Hong Ng Yip Boon Chong 《PloS one》2015,10(6)
This paper investigates the dielectric properties of urine in normal subjects and subjects with chronic kidney disease (CKD) at microwave frequency of between 0.2 GHz and 50 GHz. The measurements were conducted using an open-ended coaxial probe at room temperature (25°C), at 30°C and at human body temperature (37°C). There were statistically significant differences in the dielectric properties of the CKD subjects compared to those of the normal subjects. Statistically significant differences in dielectric properties were observed across the temperatures for normal subjects and CKD subjects. Pearson correlation test showed the significant correlation between proteinuria and dielectric properties. The experimental data closely matched the single-pole Debye model. The relaxation dispersion and relaxation time increased with the proteinuria level, while decreasing with the temperature. As for static conductivity, it increased with proteinuria level and temperature. 相似文献
73.
74.
采用点计数调查法和访问方法在2004年12月、2005年10月、2006年4月、2006年12月及2007年5月对西大明山自然保护区的三大林区(即:凤凰山林区、西大明山林区和小明山林区)冠斑犀鸟(Anthracoceros albirostris)的数量及分布情况进行了系统调查.结果显示,西大明山自然保护区的种群数量约53±8只,按保护区的面积计算种群密度为0.088ind·km2,按森林覆盖面积为0.23ind·km2.其中:凤凰山林区及西大明山林区估算冠斑犀鸟有41±5只,比2000年数据减少了约30只;小明山林区仅剩12只.结果反映西大明山自然保护区的冠斑犀鸟已处在极度濒危的边缘. 相似文献
75.
Deying Yang Yongjun Ren Yan Fu Yue Xie Huaming Nie Xiang Nong Xiaobin Gu Shuxian Wang Xuerong Peng Guangyou Yang 《The Korean journal of parasitology》2013,51(4):449-452
Taenia pisiformis is one of the most important parasites of canines and rabbits. T. pisiformis cysticercus (the larval stage) causes severe damage to rabbit breeding, which results in huge economic losses. In this study, the genetic variation of T. pisiformis was determined in Sichuan Province, China. Fragments of the mitochondrial cytochrome b (cytb) (922 bp) gene were amplified in 53 isolates from 8 regions of T. pisiformis. Overall, 12 haplotypes were found in these 53 cytb sequences. Molecular genetic variations showed 98.4% genetic variation derived from intra-region. FST and Nm values suggested that 53 isolates were not genetically differentiated and had low levels of genetic diversity. Neutrality indices of the cytb sequences showed the evolution of T. pisiformis followed a neutral mode. Phylogenetic analysis revealed no correlation between phylogeny and geographic distribution. These findings indicate that 53 isolates of T. pisiformis keep a low genetic variation, which provide useful knowledge for monitoring changes in parasite populations for future control strategies. 相似文献
76.
脊髓提取液对培养脊髓神经细胞中GABA能及DYN能神经元突起生长的影响 总被引:2,自引:0,他引:2
本文以体外培养的小鼠脊髓神经元为模型研究了人胚脊髓提取液对E12-15小鼠脊髓中GABA能神经元和DNY能神经元的突起生长的营养作用,结果发现人胚脊髓提取液在蛋白浓度为250μg/ml时对GABA能神经元的突起生长无营养作用,但对DNY能神经元的突起生长有显著的促进作用。提示了人胚脊髓提取液中有促进神经元突起生长的营养物质,且对特定胎龄的不同的神经元有不同的作用。 相似文献
77.
Wei Wei Nong Jinpeng Tang Linlong Wang Ning Chuang Chin-Jung Huang Yu 《Plasmonics (Norwell, Mass.)》2017,12(4):1205-1212
Plasmonics - In this paper, a fiber optic surface plasmon resonance sensor based on graphene-MoS2 hybrid structure is presented. The wavelength interrogation method is employed to analyze the... 相似文献
78.
We combined routinely reported tuberculosis (TB) patient characteristics with genotyping data and measures of geospatial concentration to predict which small clusters (i.e., consisting of only3 TB patients) in the United States were most likely to become outbreaks of at least 6 TB cases. Of 146 clusters analyzed, 16 (11.0%) grew into outbreaks. Clusters most likely to become outbreaks were those in which at least 1 of the first 3 patients reported homelessness or excess alcohol or illicit drug use or was incarcerated at the time of TB diagnosis and in which the cluster grew rapidly (i.e., the third case was diagnosed within 5.3 months of the first case). Of 17 clusters with these characteristics and therefore considered high risk, 9 (53%) became outbreaks. This retrospective cohort analysis of clusters in the United States suggests that routinely reported data may identify small clusters that are likely to become outbreaks and which are therefore candidates for intensified contact investigations. 相似文献
79.
L-精氨酸对大鼠心肌相对缺血/再灌注损伤保护作用的研究 总被引:4,自引:0,他引:4
目的:探索L-精氨酸(L-Arg)对心肌相对缺血/再灌损伤的保护作用,为研究抗心肌损伤的保护措施提供依据.方法:Wastar大鼠24只,随机分为对照组、相对缺血损伤组和相对缺血损伤 L-精氨酸组.采用高频阈上电刺激大鼠离体心脏建立离体心肌相对缺血/再灌注模型,分别于相对缺血前、缺血后15 min和30 min收集冠脉流出液,测定丙二醛(MDA)含量、肌酸激酶(CK)和乳酸脱氢酶(LDH)活性;采用Pclab生物信号采集处理系统测定相对缺血损伤后5 min、10 min、20 min和30 min时的心率脉压乘积(PRP)、左心室收缩压变化速率( DP/dtmax)和舒张压变化速率(-Dp/dtmAx)的恢复率.结果:L-精氨酸组的PRP、 DP/dtmax和-Dp/dtmax恢复率,明显优于相对缺血损伤组(P<0.05);L-精氨酸组的冠脉流出液和心肌组织中的丙二醛(MDA)含量、肌酸激酶(CK)和乳酸脱氢酶(LDH)活性,低于相对缺血损伤组(P<0.05),而L-精氨酸组的心肌超氧化物歧化酶(SOD)活性高于缺血组(P<0.01).结论:L-精氨酸对心肌相对缺血/再灌损伤具有一定的保护作用. 相似文献
80.
Variable-Number Tandem Repeats as Molecular Markers for Biotypes of Pasteuria ramosa in Daphnia spp. 下载免费PDF全文
Laurence Mouton Guang Nong James F. Preston Dieter Ebert 《Applied microbiology》2007,73(11):3715-3718
Variable-number tandem repeats (VNTRs) have been identified in populations of Pasteuria ramosa, a castrating endobacterium of Daphnia species. The allelic polymorphisms at 14 loci in laboratory and geographically diverse soil samples showed that VNTRs may serve as biomarkers for the genetic characterization of P. ramosa isolates. 相似文献