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1.
Xian-Hui  Dong  Dong-Xue  Ma  Tian-Ci  Zhang  Xiao-Ping  He  Li-Jun  Xu  Ya-Lei  Liu  Hao  Li  Wei-Juan  Gao 《Neurochemical research》2021,46(5):1068-1080
Neurochemical Research - Alzheimer’s disease (AD) process is characterized classically by two hallmark pathologies: β-amyloid (Aβ) plaque deposition and neurofibrillary tangles of...  相似文献   
2.
肺形侧耳味道鲜美,营养丰富,深受广大消费者喜爱。它属于四极性异宗结合担子菌,但其交配型位点结构仍未被解析。本研究利用二代测序技术对肺形侧耳的基因组进行测序,通过生物信息学方法找到了肺形侧耳野生菌株X1菌株后代单核菌株的交配型位点。结果显示肺形侧耳的A交配型位点较为特异,2株原生质体单核化菌株(X1-1和X1-15)的A交配型位点结构差异较大,X1-1含一对保守的HD1和HD2基因,而X1-15除了一对HD1和HD2基因外,还含有额外的2个HD2基因和1个HD1基因。肺形侧耳的B交配型位点与其他担子菌的交配型位点相似,含有8个信息素受体基因和1个信息素前体基因。本研究揭示的肺形侧耳特异的交配型位点结构为后期的遗传育种提供了理论依据。  相似文献   
3.
Previous studies have shown that intermittent hypobaric hypoxia (IH) preconditioning protected neurons survival from brain ischemia. However, the mechanism remains to be elucidated. The present study explored the role of nitric oxide (NO) in the process by measuring the expression of NO synthase (NOS) and NO levels. Male Wistar rats (100) were randomly assigned into four groups: sham group, IH?+?sham group, ischemia group and IH?+?ischemia group. Rats for IH preconditioning were exposed to hypobaric hypoxia mimicking 5000 m high-altitude (PB?=?404 mmHg, PO2?=?84 mmHg) 6 h/day, once daily for 28 days. Global brain ischemia was established by four-vessel occlusion that has been created by Pulsinelli. Rats were sacrificed at 7th day after the ischemia for neuropathological evaluation by thionin stain. In addition, the expression of neuronal NOS (nNOS), inducible NOS (iNOS), and NO content in the hippocampal CA1 subfield were measured at 2nd day and 7th day after the ischemia. Results revealed that global brain ischemia engendered delayed neuronal death (DND), both nNOS and iNOS expression up-regulated, and NO content increased in the hippocampal CA1 subfield. IH preconditioning reduced neuronal injury induced by the ischemia, and prevented the up-regulation of NOS expression and NO production. In addition, l-NAME?+?ischemia group was designed to detect whether depressing NO production could alleviate the DND. Pre-administration of l-NAME alleviated DND induced by the ischemia. These results suggest that IH preconditioning plays a protective role by inhibiting the over expression of NOS and NO content after brain ischemia.  相似文献   
4.
【目的】叶螨对贵州省菜豆Phaseolus vulgaris的危害日趋严重,为明确菜豆田叶螨及其天敌群落结构特征,对菜豆田叶螨防治提供依据。【方法】于2013年5月至8月对菜豆田叶螨及其天敌进行系统调查,应用群落特征参数、主成分分析法及评价函数对其群落特征、时间格局及群落稳定性进行了研究。【结果】菜豆田叶螨及天敌共有7目11科21种,其中:叶螨4种,优势种为二斑叶螨Tetranychus urticae Koch;捕食性天敌17种,优势种为南方小花蝽Orius similis Zheng。菜豆叶螨及天敌复合系统群落的多样性和均匀度随着植株的生长不断增加,但在植株生长盛期随着二斑叶螨个体数的剧增而下降,在菜豆生育中后期,由于复合生态系统中物种丰富、个体数发生量大,多样性指数和均匀度指数又呈上升趋势。对各时期复合程度的评价表明,中后期复合程度高,初期和末期复合程度低。【结论】复合系统中捕食性天敌对叶螨的控制作用大,优势种天敌表现出一定的跟随效应。  相似文献   
5.

Background

Some syphilis patients remain in a serologically active state after the recommended therapy. We currently know too little about the characteristics of this serological response.

Methods

We conducted a cohort study using the clinical database from Zhongshan Hospital, Medical College of Xiamen. In total, 1,327 HIV-negative patients with primary, secondary, latent, and tertiary syphilis were enrolled. Bivariate and multivariate analyses were utilised to identify factors associated with a serological cure and serofast state in syphilis patients one year after therapy. Chi-square tests were used to determine the differences in the serological cure rate across different therapy time points.

Results

One year after the recommended therapy, 870 patients achieved a serological cure, and 457 patients (34.4%) remained in the serofast state. The serological cure rate increased only within the first 6 months. The bivariate analysis indicated that male or younger patients had a higher likelihood of a serological cure than female or older patients. Having a baseline titre ≤1∶2 or ≥1∶64 was associated with an increased likelihood of a serological cure. The serological cure rate decreased for the different disease stages in the order of primary, secondary, latent, and tertiary syphilis. A distinction should be drawn between early and late syphilis. The multivariate analysis indicated that a serological cure was significantly associated with the disease phase, gender, age, and baseline rapid plasma reagin (RPR) titre.

Conclusions

The serofast state is common in clinical work. After one year of the recommended therapy, quite a few syphilis patients remained RPR positive. The primary endpoint of the study indicated that disease phase, gender, age and baseline RPR titre were crucial factors associated with a serological cure.  相似文献   
6.
新鲜草菇味道鲜美,香味浓郁,而且营养丰富,是具有中国特色的食药用菌。草菇采后极易开伞,低温贮藏(10℃以下)则容易自溶、渗水腐、发出异味,是最不易贮藏的食用菌之一。本课题组先前的研究表明草菇MADS-box转录因子Vvrin1基因可能在草菇菌柄的伸长、菌盖的开伞过程中起到一定的作用。因此,本研究以Vvrin1基因为研究对象,构建该基因的过表达载体,通过农杆菌介导的方法进行转化草菇异核菌株H1521菌丝块。通过潮霉素抗性平板筛选,PCR扩增潮霉素抗性基因及Vvrin1基因过表达特异片段,qRT-PCR分析拟转化子菌株内的Vvrin1基因表达量,最终获得了8个比较可靠的转化子。进一步对这些转化子的表型进行初探,发现其中7个转化子的生长速度比出发菌株H1521快,具有显著性差异(P<0.05),且转化子菌丝更浓密,菌落表面颜色更深,推测草菇MADS-box转录因子Vvrin1基因可能参与了菌丝阶段生长速度和色素合成或积累的调控。研究结果为进一步研究草菇MADS-box转录因子Vvrin1基因的功能提供了菌株材料及数据支持。  相似文献   
7.
记述了采自宁夏回族自治区泾源县野荷谷和新疆维吾尔族自治区吐鲁番市三堡乡的中国刺触螨科一新纪录亚属:杂刺触螨亚属Mixosperchon Viets,1926及两新种:凹须刺触螨Sperchon(Mixosperchon)curvipalpis Zhang et Jin,sp.nov.和吐鲁番刺触螨Sperchon(Mixosperchon)turfanensis Zhang et Jin,sp.nov..模式标本保存于贵州大学昆虫研究所.  相似文献   
8.
9.
草菇营养丰富,但不耐贮藏,现有保鲜方法无法有效延长其贮藏期,因此延长草菇保鲜期是草菇产业化工厂生产亟待解决的关键技术。本研究以V23草菇为材料,分别用1-甲基环丙烯(1-MCP)、聚赖氨酸(ε-PL)、ε-PL联合1-MCP处理草菇,比较不同处理方法对贮藏期草菇感官、理化品质的影响,筛选出草菇贮藏的最优方法。结果表明:与其他处理组相比,ε-PL联合1-MCP处理能显著减少草菇的水分散失、保持菇体质构及表面色泽(P<0.05);最佳组合处理浓度为0.3g/kg ε-PL和0.75µL/L 1-MCP,该处理下草菇能够保持良好的感官品质,维持较高水平的CAT、SOD活性,减少失水和MDA积累,抑制PPO活性,与其他不同处理组相比有显著性差异(P<0.05)。研究表明,0.3g/kg ε-PL联合0.75µL/L 1-MCP处理可以显著延长草菇货架期,为食用菌保鲜提供一个新思路。  相似文献   
10.
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