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121.
In dogs, there are several idiopathic meningoencephalitides, such as necrotizing meningoencephalitis (NME), necrotizing leukoencephalitis (NLE), and granulomatous meningoencephalomyelitis (GME). Although they are often assumed to be immune mediated, the etiology of these diseases remains elusive. In this study, the histopathology of the lesions caused by these conditions and the inflammatory cell populations produced in response to them were examined among dogs affected with GME, NME, or NLE to understand their pathogeneses. The brain tissues of dogs with NME (n = 25), NLE (n = 5), or GME (n = 9) were used. The inflammatory cells were identified by immunohistochemistry using antibodies against CD3, IgG, CD20, CD79acy, and CD163. In NME and NLE, malacic changes were located in the cerebral cortex, as well as the cerebral white matter and thalamus, respectively. The distribution of the brain lesions in NME and NLE was breed specific. In GME, granulomatous lesions that were mostly composed of epithelioid macrophages were observed in the cerebral white matter, cerebellum, and brainstem. Although the proportions of IgG-, CD20-, and CD79acy-positive cells (B cells) were not significantly different among the GME, NME, and NLE lesions, that of CD3-positive cells (T cells) was increased in GME. In NME and NLE, CD163-positive cells (macrophages) had diffusely infiltrated the cerebral cortex and white matter, respectively. However, in GME, CD163-positive cells accumulated around the blood vessels in the cerebral and cerebellar white matter. The distributions of these lesions were quite different among GME, NME, and NLE, whereas there were no marked differences in the proportions of inflammatory cells.  相似文献   
122.
Iris pseudacorus L., intentionally introduced in Japan as an ornamental plant and to improve aquatic environments, has been declared a noxious species in the Invasive Alien Species Act of Japan due to the suspected high ecological risks to the local species and ecosystems. Although prompt responses to I. pseudacorus have been sought to conserve local biodiversity, knowledge about its invasiveness is lacking. Here, we report the relationship between the establishment of I. pseudacorus and floristic changes in semi-wetland vegetation of an abandoned urban pond (Aoike), Nara City, Nara Prepecture, Japan. In total, 64 vascular plants were recorded in the pond, of which 50 were native species, seven were naturalized non-native, and seven were invasive species. On the other hand, most of these vascular plants (42 species) were grassland species and only several aquatic plants (10 species) were found in this study pond. The number of vascular plant species decreased significantly at quadrats with a coverage of I. pseudacorus above 50%. In addition, tendencies of lower number of native species and concomitant higher number of invasive species were found with increasing coverage of I. pseudacorus. From these results, we suggest that it is important to preferentially manage sites where the coverage of I. pseudacorus is above 50%, in order to preserve the local biodiversity. Additionally, as recommended in the literature, it is essential that the cut reproductive organs are kept submerged under deep water for an effective control of I. pseudacorus.  相似文献   
123.
The disinfection effect of slightly acidic electrolyzed water (SAEW) use in a farm where Pseudomonas mastitis has spread was evaluated. Despite the application of antibiotic therapy and complete cessation of milking infected quarters, numerous new and recurrent Pseudomonas aeruginosa clinical mastitis infections (5.8–7.1% of clinical mastitis cases) occurred on the farm from 2003 to 2005. Procedural changes and equipment modifications did not improve environmental contamination or the incidence of Pseudomonas mastitis. To more thoroughly decontaminate the milking parlor, an SAEW system was installed in 2006. All milking equipment and the parlor environment were sterilized with SAEW (pH 5–6.5, available chlorine 12 parts per million) before and during milking time. After adopting the SAEW system, the incidence of clinical and subclinical Pseudomonas mastitis cases decreased significantly (< 0.0001) and disappeared. These findings suggest that SAEW effectively reduced the incidence of mastitis in a herd contaminated by Pseudomonas species. This is the first report to demonstrate the effectiveness of disinfection by SAEW against mastitis pathogens in the environment.  相似文献   
124.
Contagious yawning is triggered by others yawning, and it has previously been reported in humans, primates and several experimental and companion mammals. Whereas it might be a response to an innate releasing mechanism, contagious yawning is also considered to involve emotional contagion. Here, we demonstrate that sheep, the animal model of livestock animals, also experience contagious yawning. Twelve adult castrated Corriedale sheep were used in this study. Pairs of sheep were adjacently restrained with or without a wooden divider panel to shield them from viewing the other. Their behaviors were video‐recorded for 3 days in each condition. Sheep yawned 2.0 ± 1.1 and 1.2 ± 1.1 times/day/head in the unshielded and shielded conditions, respectively. Unshielded restrained sheep yawned within 1 min after the other one 11.1% of the time, while shielded pairs did not exhibit contagious yawning. Rumination was also highly synchronized under the unshielded condition. These data reveal that contagious yawning and behavioral synchronicity occur in ruminants like sheep, making them a suitable animal model to investigate contagious yawning and the underlying mechanism.  相似文献   
125.
Background: GM2 gangliosidosis variant 0 (human Sandhoff disease) is a lysosomal storage disorder caused by deficiencies of acid β‐hexosaminidase (Hex) A and Hex B because of an abnormality of the β‐subunit, a common component in these enzyme molecules, which is coded by the HEXB gene. Objective: To describe the clinical, pathological, biochemical, and magnetic resonance imaging (MRI) findings of Sandhoff‐like disease identified in a family of Toy Poodles. Animals: Three red‐haired Toy Poodles demonstrated clinical signs including motor disorders and tremor starting between 9 and 12 months of age. The animals finally died of neurological deterioration between 18 and 23 months of age. There were some lymphocytes with abnormal cytoplasmic vacuoles detected. Methods: Observational case study. Results: The common MRI finding was diffuse T2‐hyperintensity of the subcortical white matter in the cerebrum. Bilateral T2‐hyperintensity and T1‐hypointensity in the nucleus caudatus, and atrophic findings of the cerebrum and cerebellum, were observed in a dog in the late stage. Histopathologically, swollen neurons with pale to eosinophilic granular materials in the cytoplasm were observed throughout the central nervous system. Biochemically, GM2 ganglioside had accumulated in the brain, and Hex A and Hex B were deficient in the brain and liver. Pedigree analysis demonstrated that the 3 affected dogs were from the same family line. Conclusions and Clinical Importance: The Sandhoff‐like disease observed in this family of Toy Poodles is the 2nd occurrence of the canine form of this disease and the 1st report of its identification in a family of dogs.  相似文献   
126.
127.
The dominant N2O emission source in New Zealand, calculated using the Intergovernmental Panel on Climate Change methodology, is agricultural soils. The largest source of N2O emissions in New Zealand occurs as a result of excreta deposition onto pasture during grazing. There is a dearth of studies examining the effect of soil compaction and soil aggregate size on N2O emissions from urine patches in grazed pastures. In this study, we repacked soil cores with four different soil aggregate sizes (<1.0–5.6 mm diameter), applied bovine urine, and then subjected the soil cores to four levels of soil compaction. Fluxes of N2O were monitored for 37 days after which soil cores were allowed to dry out prior to a rewetting event. There was an interaction between aggregate size and soil compaction with the cumulative loss of N2O over the first 37 days ranging from 0.3% to 9.6% of the urine-N applied. The highest N2O emissions occurred from the smallest and most compacted aggregates. Even under the highest levels of compaction the N2O loss from the large aggregates (4.0–5.6 mm diameter) was <1% of the urine-N applied. Reasons for the observed differences in the N2O flux from the different-sized aggregates included varying gas diffusivities and higher rates of denitrification in the smallest aggregates, as evidenced by the disappearance of nitrate.  相似文献   
128.
The importance of greenery in urban areas has traditionally been discussed from ecological and esthetic perspectives, as well as in public health and social science fields. The recent advancements in empirical studies were enabled by the combination of ‘big data’ of streetscapes and automated image recognition. However, the existing methods of automated image recognition for urban greenery have problems such as the confusion of green artificial objects and the excessive cost of model training. To ameliorate the drawbacks of existing methods, this study proposes to apply a patch-based semantic segmentation method for determining the green view index of certain urban areas by using Google Street View imagery and the ‘chopped picture method’. We expect that our method will contribute to expanding the scope of studies on urban greenery in various fields.  相似文献   
129.
130.
Strains of Staphylococcus species isolated from bovine mastitic milk at 66 dairy farms in Japan during the period from November 1988 to May 1989 were identified, and examined for their drug susceptibility and beta-lactamase production in order to clarify an epidemiological aspect of bovine mastitis caused by staphylococci. The results of bacteriological identification showed that the most predominant species was S. xylosus. Other major species isolated were S. aureus, S. sciuri and S. hyicus. Thirty-eight (71.7%) isolates of S. xylosus, 21 (45.7%) of S. aureus and 5 (71.4%) of S. epidermidis were positive for beta-lactamase production. Most of the beta-lactamase-producers of S. aureus were classified as high producers, although all of the beta-lactamase-positive S. xylosus isolates remained to be low producers. All isolates of S. aureus were sensitive to methicillin and cloxacillin at 6.25 micrograms/ml and 1.56 micrograms/ml, respectively, and none of methicillin-resistant S. aureus were detected. Isolates of other species were considered to be susceptible to 6 beta-lactams, in contrast to human isolates, but antibacterial activities of penicillin G and ampicillin were affected more strongly by beta-lactamase than those of methicillin, cloxacillin, cefazolin and cefoperazone.  相似文献   
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