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1.
Objective To investigate the clinical characteristics and imaging manifestations of AIDS complicated with disseminated Penicillium marneffei (PM) infection. Methods A total of 12 patients with AIDS complicated with disseminated PM infection were collected and the symptoms, signs, laboratory examination results and image manifestations of these patients were analyzed retrospectively. Results (1) The diagnosis of PM infection in all the 12 cases were confirmed by peripheral blood culture. All the 12 cases (100%) had irregular fever (38-41℃) and enlarged lymph nodes, 8 cases (66%) had skin rashes; 8 cases (66%) had hepatomegaly; 9 cases (75%) had splenomegaly while 8 cases (66%) had anemia. (2) Imaging manifestation: Five cases manifested bilateral pulmonary disseminated miliary nodular shadows or lattice signs; 1 case showed enlarged hilar lymph node and 2 cases showed patchy shadow with pleuritis. One case presented sub-pleural curve line shadow at the posterior part of the right lower lung, and adhesion between the intestinal wall and intestinal mesentery in mass form in the abdomen by CT examination. Conclusion Patients suffering from AIDS (CD4 T lymphocytes 〈50/μ L) with impaired immunity might be susceptible to complication of disseminated PM infection, which presents mainly damage of multiple organs and symptoms such as fever; enlargement of liver, spleen and lymph nodes, as well as specific skin maculopapular rashes. Imaging manifestations in the lungs were revealed as miliary nodular shadows and lattice-like shadows. Intensified abdominal CT might reveal presence of several enlarged postperitoneal lymph nodes and intestinal adhesion in shape of "cakes".  相似文献   
2.
Summary The Aspergillus nidulans acetamidase gene (amdS) has been used to transform Penicillium chrysogenum at low frequency. Several transformants were tested and shown to be mitotically stable. Southern blot analysis indicated that transforming DNA had integrated into the chromosomal DNA, possibly at multiple sites.  相似文献   
3.
A high frequency transformation system has been developed for Penicillium paxilli using pAN7-1. Up to 44% of the primary transformants were heterokaryons. Loss of hygromycin resistance was observed in primary transformants that were sub-cultured on non-selective media, but single spores of these primary transformants were mitotically stable on both selective and non-selective media. A molecular analysis of the transformants generated showed that 78% had single-site integrations, with half of these containing a single copy of pAN7-1. CHEF-gel electrophoresis showed that P. paxilli has at least six chromosomes with a total genome size of about 23.4 Mb.  相似文献   
4.
As part of a study to investigate the pathways of plasmid pAN7-1 integration in Penicillium paxilli, a molecular analysis of 90 different integration events was carried out. Twenty out of forty five integration events analyzed from transformants obtained without the addition of restriction enzyme to the transformation reaction mixture were single-copy integrations, whereas the remaining 25 were tandem-repeat integrations. The addition of restriction enzyme resulted in a shift in this ratio in favour of single-copy integration events. Analysis of the 33 tandem-repeat integration events showed that the orientation of the plasmid copies was not random, with 88% organized as tandem head-to-tail arrays. De-phosphorylation of linearized pAN7-1 did not affect the frequency with which multiple copies were integrated. This suggests that the predominant mechanism for the generation of tandem repeats in P. paxilli is by homologous recombination rather than in vivo ligation of linearized plasmids. Received: 11 March / 6 May 1997  相似文献   
5.
Random amplified polymorphic DNAs (RAPDs) were used as a genetic marker system to characterize recombinant strains following the parasexual cycle of Penicillium roqueforti. After protoplast fusion and haploidization of diploid hybrids, segregants characterized by a reassortment of the parental genetic markers displayed specific RAPD fingerprints. The appearance or the loss of RAPD fragments demonstrate that these markers provide an efficient method to analyze recombination and to characterize somatic hybrids.  相似文献   
6.
竹鼠马尔尼菲青霉菌感染的病理学研究   总被引:1,自引:0,他引:1  
目的 研究马尔尼菲青霉菌感染竹鼠的组织病理学方法。方法 应用HE,Grocotte,免疫组化染色及电镜观察。结果 马尔尼菲青霉菌引起竹鼠各脏器的组织病理学改变为化脓性病变及肉芽肿性病变,病变轻微。结论 竹鼠为马尔尼菲青霉菌的天然储库,主要侵犯竹鼠的肺和单核巨噬细胞系统。  相似文献   
7.
A 19-year-old female on chronic peritoneal dialysis developed acute peritonitis; multiple peritoneal fluid and catheter tip cultures yielded Penicillium species. She promptly responded to catheter removal and intravenous amphotericin B, followed by oral fluconazole, without further recurrences 1 year later. This is the first reported case of Penicillium peritonitis in the pediatric population. We review the microbiology and clinical spectrum of this disease, as well as the few previous reported cases in adults. Received: 2 November 1998 / Revised: 1 February 1999 / Accepted: 4 February 1999  相似文献   
8.
利用微生物转化的方法,选取桔青霉(Penicillium citrinum)为转化菌株,对头孢呋辛酯转化产率等方面进行了研究。采用枯草芽孢杆菌[CMCC(B)63501]作为检测菌株检测转化产物,结果表明,桔青霉能产生稳定的具抗菌活性的转化产物,且重现性好,转化产物的平均产率71.9%。高效液相色谱检测证明转化产物为头孢呋辛。  相似文献   
9.
叶黄素酯的生物转化研究   总被引:3,自引:0,他引:3  
陈龙胜  忻旸  周斌 《中草药》2005,36(10):1486-1488
目的对叶黄素酯进行微生物降解,以获得游离态叶黄素。方法采用青霉菌摇瓶发酵转化法,并考察了pH、发酵时间、接种量对转化结果的影响。结果青霉菌在pH值为6.0,接种量为2菌塞,发酵24 h叶黄素酯转化彻底,所得叶黄素纯度为91.6%,延长转化时间使叶黄素纯度增加,但是叶黄素质量浓度降低。结论青霉菌在发酵过程中会产生能转化叶黄素酯为游离态叶黄素的酶,发现制备叶黄素的一种新方法。  相似文献   
10.
儿童马尔尼菲青霉菌感染2例临床和病理分析   总被引:3,自引:0,他引:3  
目的 探讨儿童马尔尼菲青霉菌感染的临床特点和病理特征。方法 通过淋巴结活检和尸体解剖的肺、肝、脾、淋巴结的病理片观察真菌的形态 ;用酶免疫法和免疫印迹法检测病例 1患儿血清人类免疫缺陷病毒 (HIV)抗体 ;用流式细胞仪检测病例 1患儿的CD3、CD4、CD8和CD1 5 5 6。结果 例 1为艾滋病合并马尔尼菲青霉菌感染 ,例 2为播散型马尔尼菲青霉菌感染。例 1的CD4显著降低 ,HIV ELISA、免疫印迹法检测阳性 ,淋巴结活检可见马尔尼菲青霉菌的腊肠状细胞和桑葚小体。对例 2进行尸体解剖 ,肝、脾、淋巴结和双肺中均发现青霉菌的典型的腊肠状细胞和桑葚小体。结论 儿童马尔尼菲青霉菌感染是机会性感染 ,主要继发于先天性免疫缺陷和艾滋病 ,早期诊断、早期治疗对预后的影响很大。  相似文献   
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