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1.
Alternaria alternata is of major significance as a food and feed contaminant and is able to produce a range of mycotoxins that may elicit adverse effects in both animals and humans. We describe the isolation and characterization of five microsatellite markers for studying A. alternata. Marker polymorphism was screened in 64 isolates of A. alternata. The number of alleles per locus ranged from eight to 24, and allelic diversity ranged from 0.425 to 0.882. These markers will be useful in the study of relationships and population genetics amongst isolates of A. alternata.  相似文献   
2.
中越边境喀斯特地区有着异乎寻常的植物多样性,已经成为全球生物多样性研究和保护的热点区域,近年来在该区发现了多个苦苣苔科植物的新种或新属。凹柱苣苔属是2010年才被建立的新属,该属的花与叶相比,花较大,叶相对较小,叶片边缘稍外卷,花序仅单花,柱头盘状或凹坑状,蒴果长椭球形而有别于苦苣苔科的其他属。凹柱苣苔属为喀斯特专性植物,目前仅包括分布于黔西南的凹柱苣苔和分布于滇东南的水晶凹柱苣苔两个物种。作者在开展中越边境喀斯特地区植物多样性调查时,在越南北部的河江省发现了水晶凹柱苣苔,基于该新发现居群的植物标本,对其进行了补充描述,确认其花期为11月—12月,并对该物种濒危状况进行了重新评估,同时提供了野外生态照片以资辨认。目前,越南已记录苦苣苔科植物32属150余种,凹柱苣苔属在越南北部的发现,不仅丰富了该国苦苣苔科植物的多样性,再一次充分证明了中越边境喀斯特地区是一个完整的植物区系地理单元,而且为稀有的水晶凹柱苣苔提供了更加丰富的野外本底资料,对其将来的深入研究和保护具有重要的生物地理学和保护生物学意义。  相似文献   
3.
石蝴蝶属(Petrocosmea Oliv.)植物的现代分布与分化中心位于中国的西南山地以及周边国家和地区,如印度(阿萨姆邦)、缅甸、泰国、越南等也有分布。近年来,中国和中南半岛上各个国家和地区的新分类群和国家级新记录层出不穷,进一步加深了研究人员对中国和中南半岛植物区系以及该属植物在上述区域的多样性的理解。例如,滇黔石蝴蝶[Petrocosmea martinii (H. Léveillé)H. Léveillé]和丝毛石蝴蝶(P. sericea C.Y. Wu ex H. W. Li)曾被认为是中国的特有种,前者分布于贵州、广西北部和云南东南部,而后者仅见于云南东南部。该文报道了这两种石蝴蝶属植物的越南国家级分布新记录。这两个新记录种的发现,使得越南分布的石蝴蝶属植物种的数量上升到了5 种,这些新记录种的报道或暗示未来在与中国西南山地邻近的地区还将会有更多该属的新分类群或新记录有待发现。该文还同时提供了这两个国家级分布新记录物种的描述、图示、濒危等级现状评价以及目前所有越南已知分布的石蝴蝶属植物的检索表以备检索和核对。  相似文献   
4.
Ozone (O3) is an air pollutant with an impact increasingly important in our industrialized world. It affects human health and productivity in various crops. We provide the evidences that treatment of Arabidopsis thaliana with O3 results in ascorbate‐derived oxalic acid production. Using cultured cells of A. thaliana as a model, here we further showed that oxalic acid induces activation of anion channels that trigger depolarization of the cell, increase in cytosolic Ca2+ concentration, generation of reactive oxygen species and cell death. We confirmed that O3 reacts with ascorbate in the culture, thus resulting in production of oxalic acid and this could be part of the O3‐induced signalling pathways that trigger programmed cell death.  相似文献   
5.
报道了越南木樨科(Oleaceae)植物1 新记录种大果素馨(Jasminum macrocarpum Merr.).该种产自越南中南部嘉来省的K’Bang, Kon Ha Nung 地区, 凭证标本保存在 HN, IBSC.  相似文献   
6.
ObjectiveThe aim of this study is to assess the effects on procedural, 30-day, and 1‑year all-cause mortality by a newly introduced quality improvement strategy in patients after transcatheter aortic valve replacement (TAVR).MethodsIn October 2015, a coherent set of quality improving interventions with respect to patient geriatric screening, general diagnostic examination and safety of the procedure was implemented at a single centre in the Netherlands. Patients undergoing TAVR in 2013–2018 were included for retrospective analysis. Mortality was assessed in the pre-quality improvement strategy cohort (January 2013 to October 2015; cohort A) and in the post-quality improvement strategy cohort (November 2015 to December 2018; cohort B). Logistic regression analysis was used to estimate the influence of patient and procedural characteristics on the results of the quality improvement strategy in terms of procedural, 30-day, and 1‑year all-cause mortality.ResultsIn total, 806 patients were analysed with 274 patients in cohort A and 532 patients in cohort B. After introduction of the quality improvement strategy, procedural (4.4% to 1.3%, p < 0.01), 30-day (8.4% to 2.7%, p < 0.01) and 1‑year (16.4% to 8.5%, p < 0.01) all-cause mortality significantly decreased. Multivariate regression analysis showed that the quality improvement strategy also significantly reduced 30-day (odds ratio [OR] 0.19, 95% confidence interval [CI] 0.09–0.42) and 1‑year (OR 0.38, 95% CI 0.24–0.61) all-cause mortality if corrected for patient characteristics.ConclusionStructural meetings on evaluation of outcomes highlight potential areas for improvement and subsequent outcome-based quality improvement initiatives can result in lower procedural, 30-day, and 1‑year all-cause mortality.Electronic supplementary materialThe online version of this article (10.1007/s12471-020-01526-7) contains supplementary material, which is available to authorized users.  相似文献   
7.
A significant portion of the more than 1000 candidate cell and gene therapy products currently under clinical investigation (clinicaltrials.gov) are born out of academic research centers affiliated with universities, hospitals and non-profit research institutions. Supporting these efforts are myriad academic clinical materials production facilities with more than 40 such facilities currently operational in the United States alone. In March 2018, Stanford University's Laboratory for Cell and Gene Therapy held a symposium with the leaders and staff of more than 25 similar facilities to discuss the collective experience in developing, qualifying and operating cell and gene therapy manufacturing facilities according to current Good Manufacturing Practices. Topics included facility design, construction, staffing and operations and compliance. Leaders from several institutions gave overviews of the history of development of the facilities and discussed challenges and opportunities they had experienced over the past 10–20 years of operations. Working sessions were also held to discuss specific aspects of Process Development, Manufacturing, Quality Systems, Regulatory Affairs and Business Development with all participants contributing to the discussions. We summarize here the findings of this inaugural meeting with an emphasis on best practices and suggested guidelines for operations.  相似文献   
8.
The content and pattern of soluble isoperoxidases were determined in epidermal explants taken from different internodes of tobacco plants in the vegetative and floral states. There were qualitative and quantitative differences in the isoperoxidases, with a decrease in content and fewer bands being observed acropetally, i.e., in going from the base of the stem towards the apex. Epidermal explants from floral branches were grown in in vitro culture, with various media moditications, to form de novo floral or vegetative buds, roots or callus. Changes in soluble isoperoxidases were followed electrophoretically in relation to these varying morphogenetic pathways. In each of them, the number of bands increased on both the anodic and cathodic sides with time in culture. Compared to each other these four morphogenetic programmes were different in their peroxidase zymograms, mainly through varying kinetics in the development of activity of the isoenzymes. The changes observed during root and vegetative bud formation agree with previously published data, and the changes during floral bud formation agree with those observed in vivo.  相似文献   
9.
10.
The study aimed to explore the suicidal process, suicidal communication and psychosocial situation of young suicide attempters in a rural community in Hanoi, Vietnam. Semi-structured interviews were conducted, in a community setting, with 19 suicide attempters aged 15-24 who had been consecutively hospitalized in an intensive care unit. In 12 of 19 cases, the first pressing, distinct and constant suicidal thoughts appeared less than one day before the suicide attempt in question. However, distress and mild, fleeting suicidal thoughts had been present up to six months before the suicide attempt in 16 cases. Five respondents had a suicide plan one to three days before attempting suicide. Altogether, 13 engaged in some form of suicidal communication before their attempt. This communication was, however, difficult for outsiders to interpret. Twelve of the respondents were victims of regular physical abuse and 16 had suffered psychological violence for at least one year before attempting suicide. Eighteen of the respondents used pesticides or raticides in their suicide attempts. None sought advice or consultation in the community despite long-standing psychosocial problems. The strategy of reducing the availability of suicide means (e.g., pesticides or raticides) in Asian countries should be complemented with a long-term suicide-preventive strategy that targets school dropouts and domestic violence, and promotes coping abilities and communication about psychological and social problems as well as recognition of signs of distress and suicidal communication.  相似文献   
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