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71.
中间锦鸡儿(Caragana intermedia)耐旱、耐寒、耐盐碱,是西北干旱地区的重要固沙灌木,筛选其优良抗逆境基因,可以作为林草基因工程的基因源。该研究在中间锦鸡儿干旱胁迫转录组文库中找到1条CiPUB22 (plant U box 22)基因的cDNA全长序列,CiPUB22基因包括1 260 bp开放阅读框,编码419个氨基酸。实时荧光定量PCR结果表明,在脱水、盐和ABA处理1 h后CiPUB22基因表达量上升并达到最高水平,分别为对照表达量的12倍、35倍和7倍,干旱处理后12 d达到最高值,为对照的2.5倍,表明CiPUB22的转录水平受非生物胁迫诱导。构建CiPUB22基因的过表达载体并转化野生型拟南芥,对转基因纯合体株系抗逆性分析发现,在150 mmol/L NaCl、1 μmol/L ABA和400 mmol/L甘露醇处理下,过表达株系的萌发率均低于野生型,说明过表达CiPUB22基因降低了拟南芥在种子萌发过程中对盐和渗透胁迫的耐受性。  相似文献   
72.
73.
一种从土壤样品中选择性分离假诺卡氏菌的方法   总被引:3,自引:0,他引:3  
为提高假诺卡氏放线菌的分离效率,根据其营养特性和对抗生素的敏感性,设计、检验了5种选择性分离培养基;实验检测了模式菌株在不同培养基上的生长情况,结果表明培养基S1和S2对假诺卡氏菌的生长有显著的选择性。经该方法从韩国、印度尼西亚和中国广西地区不同土样中分离到一些假诺卡氏放线菌。  相似文献   
74.
Previous studies on the association between glycogen synthase kinase 3 beta (GSK3-β) polymorphisms (rs334558 and rs6438552) and Parkinson's disease (PD) susceptibility remained inconsistent. Thus, the goal of this study was to re-examine their exact association by a meta-analysis. All eligible studies were identified by a systematic literature search of multiple databases. Six studies (3105 cases and 4387 controls) on rs334558 and six studies (2579 cases and 4091 controls) on rs6438552 were included. The quality of these studies was generally good according to the Newcastle–Ottawa Scale (NOS). The meta-analysis showed null association between the two variants and PD susceptibility in all genetic models from the overall or Caucasian population. However, the analysis of rs334558 revealed that the risk of PD decreased in heterozygote, dominant or additive models (OR = 0.60, 95% CI: 0.48, 0.74; OR = 0.63, 95% CI: 0.51, 0.78; OR = 0.82, 95% CI: 0.71, 0.94, respectively) from the Eastern Asian population. Moreover, the analysis on the homozygote, heterozygote, dominant or additive models suggested that rs6438552 also reduced the PD risk (OR = 0.45, 95% CI: 0.24, 0.84; OR = 0.62, 95% CI: 0.39, 0.97; OR = 0.57, 95% CI: 0.37, 0.87; OR = 0.66, 95% CI: 0.49, 0.88, respectively) in the Eastern Asian population. Together, the findings suggest that the two variants both reduced the risk of PD in the Eastern Asian subgroup but not in the overall and Caucasian populations, which should be cautiously interpreted because of limited number of included studies.  相似文献   
75.
High levels of SOX4 expression have been found in a variety of human cancers, such as lung, brain and breast cancers. However, the expression of SOX4 in gastric tissues remains unknown. The SOX4 expression was detected using immunohistochemical staining and semi-quantitative RT-PCR, and our results showed that SOX4 was up-regulated in gastric cancer compared to benign gastric tissues. To further elucidate the molecular mechanisms underlying up-regulation of SOX4 in gastric cancers, we analyzed the expression of microRNA-129-2 (miR-129-2) gene, the epigenetic repression of which leads to overexpression of SOX4 in endometrial cancer. We found that up-regulation of SOX4 was inversely associated with the epigenetic silencing of miR-129-2 in gastric cancer, and restoration of miR-129-2 down-regulated SOX4 expression. We also found that inactivation of SOX4 by siRNA and restoration of miR-129-2 induced apoptosis in gastric cancer cells.  相似文献   
76.
Quercetin and other flavonoids have been reported to exhibit both antioxidant and pro‐oxidant properties. Most studies about the pro‐oxidative ability were conducted in the presence of metal ions, and the essential functional moiety of quercetin responsible for the pro‐oxidative effect is still unclear. In this study, we evaluated the pro‐oxidative abilities in the absence of metal ions of two quercetin derivatives, i.e., quercetin‐3′‐O‐β‐D ‐glucoside ( 1 ) and quercetin‐3‐Oβ‐D ‐glucoside ( 2 ), by assessing DNA cleavage and HO.‐radical production. The binding mode between these compounds and DNA was studied by fluorescence and viscometric titrations. The results showed that 1 can efficiently induce oxidative damage to plasmid DNA, while 2 shows poor activity. Both 1 and 2 bind to DNA via groove‐binding. These results proved that the α‐hydroxy‐β‐oxo‐α,β‐enone moiety contributes to the pro‐oxidative activity of quercetin.  相似文献   
77.
Senescence-accelerated mice (SAM) strains are useful models to understand the mechanisms of age-dependent degeneration. In this study, measurements of the mitochondrial membrane potential (Δψm) of platelets and the Adenosine 5-triphosphate (ATP) content of hippocampi and platelets were made, and platelet mitochondria were observed in SAMP8 (faster aging mice) and SAMR1 (aging resistant control mice) at 2, 6 and 9 months of age. In addition, an Aβ-induced (Amyloid beta-protein) damage model of platelets was established. After the addition of Aβ, the Δψm of platelets of SAMP8 at 1and 6 months of age were measured. We found that platelet Δψm, and hippocampal and platelet ATP content of SAMP8 mice decreased at a relatively early age compared with SAMR1. The platelets of 6 month-old SAMP8 showed a tolerance to Aβ-induced damages. These results suggest that mitochondrial dysfunction might be one of the mechanisms leading to age-associated degeneration in SAMP mice at an early age and the platelets could serve as a biomarker for detection of mitochondrial function and age related disease.  相似文献   
78.
李俊宁  许琪  沈岩  季梁 《遗传》2006,28(4):403-406
精神分裂症是由多基因相互作用导致的复杂疾病。对其易感基因,儿茶酚氧位甲基转移酶基因(COMT)的众多报道充满了矛盾。在对偏执型精神分裂症研究中,我们用多基因座关联分析法研究了4个涉及神经递质多巴胺代谢的基因之间的相互作用。分析结果支持如下假说:COMT-136-BclIVal108/158Met有调控作用。当前者的基因型是CC时,后者的易感等位基因型是MetA);而当前者的基因型是GG时,后者的易感等位基因型是ValG)。这一新的假说可以解释此前单基因座分析对Val108/158Met(COMT)的截然相反的报道,同时也显示了多基因座分析对复杂疾病研究的必要性。   相似文献   
79.
观察神经梅毒的临床特点,以提高对神经梅毒的诊断与治疗水平。回顾性分析哈尔滨医科大学附属第一医院2005年1月至2010年12月收治的23例神经梅毒患者的临床资料。神经梅毒患者男17例(73.9%),女6例(26.1%),男女比约为2.8∶1;年龄27~71岁,平均年龄43.1岁。本组首发症状:麻痹性痴呆(7例)、精神异常(3例)、急性脑梗死(3例)、癫痫(2例)、脊髓病变(2例)、颅高压(2例)、周围神经损害(2例)、脑神经损害(1例)、无症状性神经梅毒(1例)。23例患者血清及脑脊液快速血浆反应素实验及梅毒螺旋体血凝试验均呈阳性反应。颅脑电子计算机断层扫描(CT)和/或磁共振成像(MRI)检查多表现为额叶、顶叶、颞叶、基底节等多发病变。本组患者经大剂量青霉素治疗后病情有显著改善20例,死亡1例,自动出院2例。神经梅毒的临床表现复杂多样,神经系统各部位均可受累,诊断依靠病史及临床表现、实验室血清及脑脊液梅毒抗体检测,误诊率高,应早期诊断,诊断后应进行规范治疗,早期治疗效果较好。  相似文献   
80.
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