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排序方式: 共有1849条查询结果,搜索用时 18 毫秒
1.
目的:调查药食两用薏苡仁中污染真菌多样性,为其安全使用提供参考依据。方法:收集薏苡仁样品18批,提取真菌DNA并扩增ITS2序列,基于Illumina MiSeq PE250平台进行高通量测序。结果:共检测到4门18纲44目99科149属的真菌,子囊菌门Ascomycota是最优势菌门,镰刀菌属Fusarium(3.05%~60.32%)是属水平最优势属,其次是曲霉属Aspergillus(2.20%~45.44%)、白僵菌属Beauveria(0.07%~63.21%)、链格孢属Alternaria(0.80%~11.92%)、Arachnomyces(0.03%~39.36%)和青霉属Penicillium(0.24%~8.03%)。此外,共检测到5种潜在产毒真菌,分别是烟曲霉A.fumigatus、土曲霉A.terreus、梨孢镰刀菌F.poae、囊状青霉P.capsulatum和展青霉P.paxilli。结论:高通量测序技术可以快速有效地检测薏苡仁中污染真菌种类,为薏苡仁污染真菌毒素提供风险预警。 相似文献
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Thara Keloth Debasis Gochhait S Sivaranjani Neelaiah Siddaraju 《Diagnostic cytopathology》2019,47(8):828-830
Phaeohyphomycosis is a chronic subcutaneous fungal infection caused by dematiaceous fungi, commonly involving the extremities, which present as single or multiple lesions mimicking a benign tumor. Fine‐needle aspiration cytology (FNAC) is an easy method for the diagnosis of the lesion. Morphology of the fungus is characteristic with no difficulty for cytopathologist for identification; with a close differential diagnosis of Candida and Aspergillosis. The special stains like periodic acid schiff (PAS) highlights the fungus and the Masson Fontana confirm the melanin pigment and dematiaceous nature of the fungi. Liquid‐based cytology (LBC) preparation of the aspirated material was attempted, which is not usually performed on day to day basis. However, in our case the conventional smears were better for appreciating the fungal morphology. 相似文献
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Antioxidantive activities and gastrodin determination of extracts of endophytic fungi isolated from Gastrodia elata Bl. 下载免费PDF全文
Gastrodia elata Bl. is a traditional Chinese herbal medicine with special pharmacological effects on headache and numbness. However, its wild sources are now in short supply because of over-excavation. A total of 14 endophytic fungi were isolated from Gastrodia elata Bl collected from Yinjing, in which 10 strains were identified, including Neonectria, Ascomycota, Fusarium, Oidiodendron and Dothiorella. All crude extracts showed some degrees of antioxidant activities by T-AOC method and DPPH methods, especially those from Oidiodendron GeR6 and Ascomycota sp. GeR2, which might be attributed due to their high phenolic contents. However, only Oidiodendron GeR6 contained gastrodin (39.2 μg/g) as the host plant in the crude extracts. In conclusion, the notable activities of GeR6 indicated its medical use as a natural antioxidant agent, as well as substitutable use for Gastrodia elata Bl. in the future. 相似文献
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《Journal de Mycologie Médicale》2020,30(1):100918
We report a case of cerebral phaeohyphomycosis, a fungal brain infection due to a dark (dematiaceous) fungi in a 6-year-old French Guyanese boy. The child presented fever and drowsiness due to several paraventricular brain abscesses. Neurological surgeries were performed to reduce intracranial hypertension and to obtain abscess biopsies. Mycological cultures of intraoperative samples led to the diagnosis of cerebral phaeohyphomycosis due to Cladophialophora bantiana. The patient neurological status deteriorated and remained critical after several weeks of combination antifungal therapy with voriconazole 8 mg/kg/day, liposomal amphotericin B 10 mg/kg/day and flucytosine 200 mg/kg/day. A complete surgical resection was not possible because of multiple small abscesses. A multidisciplinary ethical staff decided on home medical care with palliative ventriculoperitoneal shunt, nasogastric feeding and analgesics. One year later, the patient's neurological condition had improved and cerebral lesions had regressed, while he had not received any antifungal treatment but only traditional medicines. Cerebral phaeohyphomycosis are rare diseases affecting immunocompromised but also apparently non-immunocompromised patients, as in this case. A complete surgical resection is not always possible and mortality rates are high in spite of treatments with a combination of antifungals. The diagnosis may be difficult because of these dematiaceous fungi's slowly growing and their potential pathogenicity for laboratory staff. 相似文献
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目的探讨可见光连续环境消毒系统(CED)对手术室真菌和细菌气溶胶浓度的影响以及与环境因素的相关性。方法以焦作市第二人民医院5间手术室作为研究对象,分别对CED应用前后手术室内生物气溶胶浓度进行检测,并进行真菌和细菌培养,将检测结果进行比较,并与同期检测的消毒前后的室内温度和湿度相关性进行分析。结果消毒前和消毒后强化消毒模式下手术室内细菌、真菌浓度均较常规消毒模式降低,其次术后消毒完成后强化消毒模式下室内相对湿度相比常规消毒降低,差异均有统计学意义(P<0.05)。消毒过程中手术室的相对湿度标准值为(41.12±4.06)%,温度为(23.41±2.07)℃。经Spearman相关分析显示,消毒后真菌和细菌浓度与相对湿度标准值呈正相关(r=0.109,0.107;P=0.034,0.037),与温度无相关性(P>0.05)。结论常规消毒措施上加用可见光连续环境消毒系统能大大降低手术室的菌群生物气溶胶浓度,同时维持室内相对湿度减少细菌和真菌的繁殖。 相似文献
8.
目的 研究中国南海石珊瑚Stylopgora Stylophora pistillata的化学成分。方法 运用硅胶、凝胶(Sephadex LH-20)等多种柱色谱手段对化合物进行分离纯化;利用核磁共振、质谱等波谱学手段并结合其理化性质及文献数据鉴定化合物的结构。结果 从石珊瑚Stylopgora Stylophora pistillata的乙醇提取物中共分离鉴定了8个单体化合物:1,3-十四烷酸甘油二酯(1),正二十五烷(2),正二十三烷(3),肉豆蔻酸(4),2, 2"-氧代双(1, 4-二叔丁苯)(5),(R)-2-乙基己醇(6),2, 2"-bis(4-hydroxyphenyl)propane bis(2,3-epoxypropyl)ether(7)和5-hydroxy-3,4-dimethy-5- pentyl-2(5H)-furanone(8)。结论 化合物1~8均为首次从该石珊瑚中分离得到。细胞毒活性测试结果表明,化合物7对人慢性髓原白血病细胞(K562)、人肝癌细胞(BEL-7402)、人胃癌细胞(SGC-7901)、人肺癌细胞(A549)和人宫颈癌细胞(Hela)的增殖显示出一定的生长抑制活性,其余化合物对上述肿瘤细胞均无生长抑制活性。 相似文献
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Endophytic fungi are known to play an important role in driving the evolution of plants by conferring adaptational advantages to their host through the production of secondary metabolites and phytohormones. In this study, we evaluated the diversity and phylogenetic relationship of endophytic fungal communities from four Dendrobium species viz., Dendrobium chrysanthum, Dendrobium heterocarpum, Dendrobium hookerianum, and Dendrobium longicornu of Meghalaya, India. A total of 51 culturable endophytic fungi were isolated from the four selected orchid species. The isolates were identified based on nuclear large subunit sequences into 33 species. Approximately 91% of the isolates showed affinity to Ascomycetes, while 9% of the isolates showed BLAST search similarity to Basidiomycetes. The most common genera were Trichoderma and Xylaria. The most prevalent genera were Fusarium, which was detected in all the four Dendrobium species followed by Diaporthe, which was present in three Dendrobium species viz., D. chrysanthum, D. hookerianum, and D. heterocarpum. The Shannon index value of endophytic fungal communities was the highest in D. chrysanthum (2.66), while D. longicornu (1) had the highest Evenness index. The present study revealed that endophytic fungi in these orchids are an amalgam of pathogenic and beneficial fungi, which have, at the least, switched their lifestyle to asymptomatic endophyte in their host. To our knowledge, this is the first such report on the diversity of endophytic fungi in the four selected Dendrobium species from Meghalaya, India. 相似文献
10.
共生真菌分布广泛,与植物形成共生体。研究表明,某些共生真菌可以增强植物对生物胁迫和非生物胁迫,包括干旱、高温、矿物质失调和高盐的耐受性,从而使被内生真菌感染的植株比未感染植株对有限的资源更具竞争力而且生长得更好。植物共生真菌可以通过多样化途径来增强植物体的抗性机能,其提高抗旱性的机制主要表现在营养物质的吸收、植物的保护系统、激素调节、水解酶、水分代谢、相关基因表达、植物防御信号途径等方面。总结共生真菌提高植物耐旱性的机制研究进展,以使读者能全面、及时地了解这一领域的研究动态。 相似文献