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991.
In spring 1996, extensive leaf necrosis and twig dieback were observed on young sweet persimmon (Dyospiros kaki L.) trees, cultivars O'Gosho, Hachija, Mercatelli and Kaki-tipo planted in the Abruzzo region (central Italy). Many trees were killed. When the dieback reached the trunk, in many cases, new vegetation was noticed above the graft point. The cultivar Jiro-C was not affected by the disease. During 1997, no symptoms were observed on any plant. The orchard was planted in a clay soil with a very low content of organic matter. Biochemical, nutritional and pathogenicity tests indicated Pseudomonas syringae pv. syringae van Hall as the causal agent of the disease. This is the first report of this bacterium as a pathogen of sweet persimmon in Europe.  相似文献   
992.
To investigate the relationship between European starlings and bovine coccidiosis we collected samples from European starlings, cattle feed bunks, cattle water troughs, and cattle feces within concentrated animal feeding operations (CAFOs). These samples were screened for coccidia spp. to investigate (i) the prevalence of coccidia in starlings using CAFOs; (ii) if there is a relationship between bovine coccidiosis and starling numbers; (iii) if coccidia contamination of cattle feed and water is related to the number of starlings observed on CAFOs. Coccidia belonging to the genus Eimeria were detected in cattle feces and one water sample but no Eimeria spp. were detected in European starlings or cattle feed. However, many European starling samples were positive for Isospora. Starling use of CAFOs did not appear to be associated with coccidia spp. shedding by cattle and there was no correlation between starling numbers and contamination of cattle feed and water, suggesting that starling do not contribute to the amplification and spread of Eimeria in CAFOs.  相似文献   
993.
Sera collected from apparently healthy 6-12-month-old cats (n = 31) presented to the Society for the Prevention of Cruelty to Animals Veterinary Clinic in Bloemfontein for neutering were tested for antibodies reactive to Bartonella henselae (Houston-1 strain) by indirect fluorescent antibody testing. Whole blood collected from the cats was used in isolation experiments and subsequent identification of Bartonella species was based on comparison of the nucleotide base sequence of polymerase chain reaction-amplified citrate synthase gene fragments. While none of the cats had antibodies reactive with B. henselae at titres > or =1/64, an organism with a partial citrate synthase gene sequence identical to that of B. henselae (Houston-1) was isolated from 1 cat.  相似文献   
994.
995.
A 15‐year‐old, neutered male, Shih Tzu cross developed progressive corneal stromal thickening and vascularization of the right eye, and 5 months later, of the left eye. Both eyes became blind due to extensive corneal opacification and were enucleated. Light microscopic examination revealed a diffuse corneal infiltrate of neoplastic mesenchymal cells, and immunohistochemistry revealed diffuse cytoplasmic vimentin immunoreactivity and variable cytoplasmic and nuclear immunoreactivity for S100 in the neoplastic cells. Transmission electron microscopy revealed desmosomes between contiguous cells, thread‐like cytoplasmic processes coated with basement membrane, extracellular bundles of collagen, and axonal degeneration consistent with features of a nerve sheath neoplasm. This is the first report of primary, bilateral corneal nerve sheath sarcoma in a canine.  相似文献   
996.
In greenhouse and field experiments, shedding of pepper leaves infected withLeveillula taurica was inhibited by treatments with indole acetic acid or butyric acid. Spraying with MnSO4 increased shedding in greenhouse trials.  相似文献   
997.
998.
Perineuronal nets (PNs) of condensed extracellular matrix (ECM) have been shown to characterize the microenvironment of individual neurons and the chemoarchitecture of some brain regions. In the present study, PNs in the hippocampus were visualized with a cationic iron colloid method for sulphated proteoglycan content and a plant lectin from Vicia villosa agglutinin (VVA) for N-acetylgalactosamine containing glycoconjugates. The ECM molecules were organized in reticular coats (PNs) around non-pyramidal cells in the Ammons horn (Corneu Ammons, CA) and subicular region, in addition to pyramidal neurons located in CA2 and CA3 regions. CA2 stratum pyramidale exhibited the most intense staining of its PNs and a diffuse intervening neutrophil labelling, while CA3 region showed a graded fashion of staining intensity. The subiculum displayed intensely stained perineuronal coats. Notably, the hippocampal perineuronal nets revealed overlapped staining characteristics with both staining methods. However, cell coats of the subicular neurons showed various degrees of labelling characteristics with both markers. It is suggested that the PNs in the hippocampus are correlated with the fast spiking inhibitory GABAergic neurons and their target pyramidal cells, and this is important to keep the excitatory elements under control and therefore control the information processes within the hippocampus.  相似文献   
999.
In order to assess postoperative outcome in horses undergoing end-to-end anastomosis of the small intestine, performed using a one-layer technique, 15 horses that underwent exploratory coeliotomy, resection of the small intestine and end-to-end anastomosis using a continuous Lembert pattern were studied. Information on the age, breed, sex, diagnosis, treatment, complications and outcome of each case were obtained from medical records. Follow-up information was obtained via telephone conversations with clients and trainers. Five of the horses had short-term postoperative complications: one had postoperative ileus (POI), colic and peritonitis, one had POI and colic, two had POI only and one had diarrhoea only. A second exploratory coeliotomy was recommended in two of the 15 horses (13 per cent). The short-term survival rate, defined as survival up to the time of discharge from the hospital, was 93.3 per cent (14 of 15 horses). The long-term survival rate, defined as survival for at least 12 months after the surgery, was 84.6 per cent (11 of 13 horses followed up).  相似文献   
1000.
Lymphocyte subsets, major histocompatibility complex (MHC)-II expressing cells and number of amastigotes in the epidermis and dermis were investigated immunohistochemically in 48 dogs with patent leishmaniosis, with or without exfoliative dermatitis (ED) to study the immunopathogenesis of this common cutaneous form of the disease. Skin biopsies were obtained and compared for ED sites (group A, n = 26), normal-appearing skin from the same animals (group B, n = 24), and leishmanial dogs not exhibiting ED (group C, n = 22), and normal controls (group D, n = 22). The CD3+, CD45RA+, CD4+, CD8+ (CD8a+), CD21+, and MHC-II+ cells and leishmania amastigotes were identified immunohistochemically and counted with the aid of an image analysis system. Pyogranulomatous to granulomatous dermatitis, expressed in various histopathological patterns, was noticed in all groups A and B and in half of group C dogs. In the epidermis, the low number of T-cells and their subsets did not differ significantly between groups A and B, but CD8+ outnumbered CD4+ lymphocytes in both groups. MHC-II+ expression on epidermal keratinocytes was intense in the skin with and without lesions from dogs with ED but not in group C dogs. CD3+, CD8+ and MHC-II+ cells were fewer in group C compared to group A and B dogs. In the dermis, CD3+ cells in group A animals were mainly represented by the CD8+. CD45RA+ and CD21+ cells were also seen in high numbers. MHC-II expression, potentially in lymphocytes, fibroblasts, dendritic cells, and macrophages was intense. The numbers of all cellular subpopulations in the dermis were significantly different between the groups, being highest in group A and lowest in group D. In sebaceous adenitis sites, CD4+ outnumbered CD8+ cells in contrast to the neighbouring dermis and the epidermis. The number of CD21+ and CD45RA+ cells was much lower in the inflamed sebaceous glands compared to the dermis. Finally, the number of amastigotes in the normal-appearing skin was significantly higher in the ED dogs (group B) than in those not exhibiting this cutaneous form of the disease (group C).  相似文献   
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