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Acidovorax citrulli is a seed-transmitted gram-negative bacterium that can cause substantial economic yield loss in watermelon and melon production worldwide. Four small-molecule libraries containing 4,952 compounds were selected for high-throughput screening against Acitrulli wild-type strain Xu3-14 by evaluation of growth inhibition. One hundred and twenty-seven molecules (2.5% hit rate) were identified as bactericidal or bacteriostatic against Acitrulli at 100 μM. Secondary screens indicated that 27 candidate compounds were more effective against Acitrulli Group II strains than Group I strains (classified using repetitive element PCR). Several compounds were inhibitory to other pathogenic bacteria, including Clavibacter michiganensis subsp. michiganensis and Xanthomonas campestris pv. campestris, but did not affect the growth of plant beneficial bacteria Pseudomonas fluorescens and Bacillus subtilis. More than half of the compounds did not inhibit germination of Arabidopsis or watermelon seeds. The effect of small molecules on Acitrulli seed-to-seedling transmission was evaluated by applying each compound to inoculated watermelon seeds and assessing seedling infection. Nine compounds were chosen for further investigation based on their reduction of percentage seedling infection and compiling scores on their specificity, sensitivity, and phytotoxicity obtained in the secondary screens. The five best compounds were selected (thiamphenicol, nadifloxacin, pipemidic acid, ciclopirox, and zinc pyrithione) for greenhouse tests and were found to effectively reduce the seed-to-seedling transmission of Acitrulli in both artificially and naturally infested seeds. These top five compounds provide a basis for future development of an Acitrulli-specific bactericide.  相似文献   
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Mastitis is a common reproductive disorder in bitches, reaching a prevalence of 0.71%. Mastitis has a wide range of forms, from asymptomatic to severe gangrenous mastitis that can lead to septic shock and death of the bitch and nurslings. However, most of the time it is overlooked, undiagnosed or mistreated. The present systematic review was performed to revise and summarize the existing knowledge related to this disorder, including diagnosis, treatment and prevention.  相似文献   
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In Poland's pine forests, mistletoe (Viscum album subsp. austriacum) abundance has increased over the past 20 years. This mistletoe infestation has decreased the growth and vigour of Scots pine trees. In this study, we surveyed the culturable fungi from healthy and diseased V. album subsp. austriacum leaves from two stands in Poland. In total, 63 distinct species were identified, 99.8% of which belonged to the phylum Ascomycota. The community compositions of fungi in mistletoe leaves were similar in healthy and diseased leaves as Alternaria alternata, Aureobasidium pullulans, Botryosphaeria visci, Fusarium paeoniae and Microsphaeropsis olivacea were consistently found in leaves of all symptom types. The most frequently isolated fungus from asymptomatic leaves was M. olivacea, followed by A. alternata, A. pullulans and Hypoxylon rubiginosum. In comparison, the most frequently isolated fungi from leaves with rusty-brown necrotic spots were (in decreasing order) M. olivacea, B. visci, F. paeoniae and A. alternata, while the most frequently isolated fungi from leaves with black or dark brown spots were M. olivacea, A. alternata, A. pullulans, Epicoccum layuense and F. paeoniae. This study was the first comprehensive report showing that certain fungal species may be pathogens of V. album subsp. austriacum in Poland. This study was also the first report of F. paeoniae, F. juglandicola, Diaporthe vacuae and Heterotruncatella spartii from V. album, and the first report of D. vacuae and H. spartii in Poland.  相似文献   
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The breast and shoulder-blade muscles of a roe (Caprelous capreolus L.), shot in a hunting district in western Bohemia, were found to contain cysticerci with morphological characters and size corresponding to those of Cysticercus tarandi, which is a developmental stage of the tapeworm Taenia krabbei Moniez, 1879. The surface as well as deeper layers of muscle contained one to two cysticerci per 100 cm2 of area. The authors describe the larvocysts and histological changes in the site where the micro-organisms were found. The cysticerci are discussed as to the species to which they belong.  相似文献   
8.
The effects of drugs containing vitamin E for peroral administration (Combinal E), intramuscular injection (Erevit) and parenteral administration of a combined drug containing vitamin E and selenium (Selevit) on vitamin E levels in the ovine blood serum were studied. A uniform dose of 15 mg tocopherol acetate per 1 kg live weight was administered to the experimental animals. The level of vitamin E after the peroral administration of Combinal E was affected to a lesser extent than in swine and calves. The serum was examined before and after saponification to determine the effect of the intramuscular injection of Erevit; it was found out that tocopherol acetate prevailed in the blood serum in the first hours after such a route of administration. The best results were obtained after both subcutaneous and intramuscular administration of Selevit, the levels of free tocopherol showing high values even at the end of the experiments. These results may be made use of in determining effective preventive and therapeutic measures to do away with the white muscle disease in practice.  相似文献   
9.
This study involved the comparison of suitability of different methods for routine diagnostics of Cryptosporidium spp. Two staining methods, one concentration-sedimentation method, seven concentration-floatation methods and one combined floatation-sedimentation method were compared. The methods were tested with two concentrations (1 x 10(5) and 1 x 10(6)/g) of C. parvum and C. andersoni. The methods were evaluated using light microscope, magnification 400x for concentration methods and 1000x for stained samples respectively. Specificity of both staining methods was 95-100%. Ziehl-Neelsen with P < 0.01 is more suitable for identification of C. andersoni and modified Milácek-Vítovec with P < 0.01 for identification of C. parvum. Concerning specificity and sensitivity, the floatation-concentration method by Sheather was found to provide the best results of all selected methods. The merthiolate iodine formaldehyde concentration (MIFC) method was the least specific one. The least suitable method concerning sensitivity and costs was the floatation method with caesium chloride (CsCl) with a specificity of 29%.  相似文献   
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