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81.
Scientists studying diseases of invertebrates in the USA, Europe, and Asia began to meet at international congresses in the 1950s and early 1960s, and soon recognized that they needed both a society and a journal where their common interests could be discussed and their findings presented. Edward A. Steinhaus played a major role in bringing together scientists from across the globe with common interests in these diseases. As a consequence, the Journal of Invertebrate Pathology (then Journal of Insect Pathology) was initiated in 1959 and Steinhaus became its first editor. Along with Albert Sparks he organized a meeting at Seattle, Washington in 1967 that led to the founding of the Society for Invertebrate Pathology with Steinhaus as its first President. The Society held its first meeting at Ohio State University in 1968, and has continued to meet annually. The Society has instituted a Founder's Lecture series, graduate student awards, and Divisions of Microbial Control, Microsporidia, Bacteriology, Fungi, Viruses, and Nematodes. Members enjoy several social functions at meetings as well as symposia, submitted papers, and poster sessions. The Society for Invertebrate Pathology is a truly international organization which to date has held meetings in 13 countries and 14 US states, usually attended by members from at least 20 countries.  相似文献   
82.
The histopathological changes induced by Echinostoma caproni (Trematoda: Echinostomatidae) in a high (golden hamster) and a low compatible host (rat) were compared at 15 and 30 days post-infection. Infection of rats was characterized by a progressive increase in erosion of villi and elevated numbers of goblet cells, which could be related to the early expulsion of the parasite in a host of low compatibility. In contrast to rats, the number of goblet cell in E. caproni-infected hamsters was low, but increased numbers of neutrophils and mesenteric inflammatory cells were observed. This indicated that local inflammatory responses in hamsters were greater than in rats. An immunohistochemical study using polyclonal IgG anti-E. caproni excretory-secretory antigens demonstrated a greater level of passage of E. caproni antigens through the intestinal mucosa in hamsters than in rats, probably in relation to the greater inflammatory response. Our results indicate the fact that early inflammatory responses could be important for the establishment of E. caproni chronic infections in highly compatible hosts.  相似文献   
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84.
Canalicular adenoma is an uncommon benign tumour that generally arises in the minor salivary glands of individuals over 60 years old. This study illustrates a case of canalicular adenoma in a 70-year-old female, presenting as two distinct asymptomatic nodules in the upper lip. Immunohistochemistry analysis was performed. Clinical features, management, histology and immunoprofile from this case and from the literature are discussed.  相似文献   
85.
Aim: This study aimed to evaluate the effect of bromelain, a cysteine protease isolated from pineapple (Ananas comosus), on growth of several agronomically important fungal pathogens. Methods and Results: Purification of bromelain from pineapple stems was carried out by chromatography techniques, and its antimicrobial activity was tested against the fungal pathogens Fusarium verticillioides, Fusarium oxysporum and Fusarium proliferatum by broth microdilution assay. A concentration of 0·3 μmol l?1 of bromelain was sufficient for 90% growth inhibition of F. verticillioides. The capability of bromelain to inhibit fungal growth is related to its proteolytic activity. Conclusions: The study demonstrates that stem bromelain exhibits a potent antifungal activity against phytopathogens and suggests its potential use as an effective agent for crop protection. Significance and Impact of the Study: The results support the use of a natural protease that accumulates at high levels in pineapple stems as alternative to the use of chemical fungicides for crop protection.  相似文献   
86.
The aim of our study was to identify relationships between epigenetic parameters correlating with a relaxed chromatin state of the DUX4 promoter region and clinical severity as measured by a clinical severity score or muscle pathologic changes in D4Z4 contraction-dependent (FSHD1) and –independent (FSHD2) facioscapulohumeral muscular dystrophy patients. Twenty primary fibroblast (5 control, 10 FSHD1 and 5 FSHD2) and 26 primary myoblast (9 control, 12 FSHD1 and 5 FSHD2) cultures originating from patients with FSHD and controls were analyzed. Histone modification levels were determined by chromatin immunoprecipitation. We examined correlations between the chromatin compaction score (ChCS) defined by the H3K9me3:H3K4me2 ratio and an age corrected clinical severity score (CSS) or muscle pathology score (MPS). Possible relationships were investigated using linear regression analysis and significance was tested by Pearson’s product-moment coefficient.   We found a significant difference of the ChCS between controls and patients with FSHD1 and between controls and patients with FSHD2. Tissue specific differences in ChCS were also observed. We also found a near-significant relationship between ChCS and the age corrected CSS in fibroblasts but not in myoblasts. Surprisingly, we found a strong correlation between the MPS of the vastus lateralis and the CSS. Our results confirm the D4Z4 chromatin relaxation previously shown to be associated with FSHD in a small number of samples. A possible relationship between clinical and epigenetic parameters could be established in patient fibroblasts, but not in myoblasts. The strong correlation between the MPS of the vastus lateralis and the CSS suggests that this muscle can be used to study for surrogate markers of overall disease severity.  相似文献   
87.
A new defoliating disease was observed on 20-year-old trees of Lecythis pisonis in Viçosa, Minas Gerais, Brazil. The disease is characterized by forming one or more large zonate epiphyllous leaf spots with a light brown to white center, followed by two to three zones gradually varying from brown to red-brown. On the corresponding abaxial leaf surface, the spots are lighter with a profuse greenish gray coloration caused by the fungal colonies. In PDA culture, the fungus is characterized by a slow growth of the colonies with brown-violet pigmentation at the reverse. Inoculation tests carried out on healthy plants of L. pisonis confirmed the pathogenicity of this fungus. Periconiella lecythidis sp. nov., the causal agent of the zonate leaf spot disease of L. pisonis is described, illustrated, discussed and compared with the other species of the genus Periconiella. The intricate generic affinity within a complex of morphologically similar hyphomycete genera consisting of Metulocladosporiella, Parapericoniella, Penidiella and Periconiella is discussed in detail.  相似文献   
88.
A novel form of phosphate activated glutaminase (PAG), catalyzing the synthesis of glutamate from glutamine, has been detected in cultured astrocytes and SH-SY5Y neuroblastoma cells. This enzyme form is different from that of the kidney and liver isozymes. In these cells we found high enzyme activity, but no or very weak immunoreactivity against the kidney type of PAG, and no immunoreactivity against the liver type. PAG was also investigated in brain under pathological conditions. In patients with Down's syndrome the immunoreactivity in the frontoparietal cortex was significantly reduced. The findings leading to our conclusion of a functionally active PAG on the outer face of the inner mitochondrial membrane are discussed, and a model is presented.  相似文献   
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90.
为了研究禽流感H5N1病毒在各个器官的增殖和病理变化,在生物安全实验室,我们将禽流感H5N1病毒通过尾静脉接种BALB/C小鼠。结果小鼠在不经过适应的情况下,直接感染发病,甚至死亡。在观察的7天内,感染小鼠临床症状主要表现呼吸急促,体温、体重下降。尸检表现肺出血,心外膜坏死以及肝脏的坏死。组织病理检查表现心、肝、肺等多器官的病变。肺的病变伴有纤维化的弥漫性肺泡损伤;心肌外膜大量淋巴细胞浸润、坏死;肝细胞大量坏死,淋巴细胞浸润。心、肝的坏死病变在H5N1禽流感病毒相关的研究中未见报道。经过对各个组织器官的病毒载量的检测,未发现病毒在各个病变组织中的复制。免疫组化的检测,各个组织中也未检出阳性的细胞反应。因此,我们认为H5N1禽流感病毒感染小鼠引起多个器官组织的损伤,甚至死亡,不是病毒在器官的复制,而可能是病毒感染小鼠,产生炎症细胞因子的高度表达,损伤多个器官组织所致。  相似文献   
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