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排序方式: 共有472条查询结果,搜索用时 26 毫秒
441.
Tomoyuki Shibahara Atsutoshi Kuwano Takanori Ueno Yoshinari Katayama Tatsuo Ohya Sadao Taharaguchi Shinji Yamamoto Takashi Umemura Yoshiharu Ishikawa Koichi Kadota 《Journal of veterinary diagnostic investigation》2005,17(2):145-150
Studies of equine intestinal spirochetes have long focused on intestinal contents alone, but intestinal spirochetosis has been reported recently in a 21-month-old Thoroughbred colt in Japan. To define the clinical and pathological significances of intestinal spirochetosis in several horses, an epizootiologic survey with histologic, immunohistochemical, and ultrastructural methods was conducted for Brachyspira antigen-containing intestinal spirochetes in 12 diseased or injured Thoroughbred horses, aged from 35 days to 17 years. Brachyspira antigen-containing spirochetes were found in 7 of 12 horses (58.3%) and were more frequent in the cecum than in other parts of the bowel. It was not clear whether the infection was clinically related to diarrhea or dysentery, but histopathology revealed a close association between the bacterial infection and epithelial hyperplasia. Crypt epithelium consisted mainly of goblet cells and showed frequent mitosis throughout its length. Inflammatory cells and congestion were also present. There were numerous spirochetes in the crypts, and some invaded the cecal and colonic epithelia and underlying lamina propria. Ultrastructurally, the spirochetes were divided into 4 types. Three types were identified in degenerative epithelial cells or intracellularly. Brachyspira antigen-containing intestinal spirochetes invading the mucosa were capable of causing epithelial hyperplasia in the cecum and colon in the horses. The findings in this study will increase awareness of the importance of intestinal spirochetosis and may also be helpful for diagnosis and treatment of this condition. 相似文献
442.
Evaluation of meat meal, chicken meal, and corn gluten meal as dietary sources of protein in dry cat food 总被引:1,自引:0,他引:1 下载免费PDF全文
Masayuki Funaba Yuko Oka Shinji Kobayashi Masahiro Kaneko Hiromi Yamamoto Kazuhiko Namikawa Tsunenori Iriki Yoshikazu Hatano Matanobu Abe 《Canadian journal of veterinary research》2005,69(4):299-304
The nutritional value of meat meal (MM), chicken meal (CM), and corn gluten meal (CGM) as dietary sources of protein in dry food formulated for adult cats was evaluated. Twelve healthy adult cats (11 males and 1 female) were used. Dry diets containing MM, CM, or CGM as the main protein source were given for a 3-week period in a 3 x 3 Latin-square design. Digestion and balance experiments were conducted during the last 7 d of each period. In addition, freshly voided urine was taken to determine urinary pH and number of struvite crystals. As compared with the CM diet, dry-matter digestibility was higher and lower for the MM and CGM groups, respectively. Percentages of nitrogen (N) absorption and N retention to N intake were higher in the MM group, and N utilization was not different between the CM group and the CGM group. All cats excreted alkaline urine (pH > 7). Urinary pH, struvite activity product, and number of struvite crystals in urine were lower for the CGM group. There was no difference in retention of calcium and magnesium among the groups. From the point of view of digestibility and N utilization, MM is superior to CGM, and CM is better than or equivalent to CGM as a protein source of dry foods for adult cats. However, when CM is used as a dietary protein source, some manipulation of dietary base excess may be needed to control urinary acid-base balance, because CM contains higher calcium and phosphorus. 相似文献
443.
Marker-exchanged mutants of phoP and phoQ of Erwinia chrysanthemi (Ech) strain 3937 became more sensitive to the cationic antimicrobial peptide (CAMP) magainin II than did the wild type at a low Mg2+ concentration and at either acidic or neutral pH. At high Mg2+ and acidic pH, only the phoQ mutant, but not the phoP mutant, became more sensitive to magainin II than did the wild type; both mutants were more sensitive at neutral pH. The hyperinduction of Pel synthesis in medium containing plant extracts and polygalacturonic acid (PGA) was confirmed in the wild type but not in the mutants at low Mg2+ and neutral pH. However, Pel was hyperinduced at high Mg2+ and neutral pH in these mutants but not in the wild type. Maceration was also greatly reduced by these mutants compared to the wild type when the inoculum was precultured and then resuspended in the medium with low Mg2+ at neutral pH. However, when bacteria were precultured and resuspended in the medium with high Mg2+ at neutral pH, severe maceration was observed in these mutants but not in the wild type. Thus, at low Mg2+, PhoP-PhoQ TCS seems to be stimulated for maceration and the hyperinduction of Pel synthesis. At high Mg2+, however, PhoP-PhoQ TCS may be repressed for these phenotypes, and PhoP may be controlled by a mechanism(s) other than PhoQ regulation. 相似文献
444.
Isolates of Banana bunchy top virus (BBTV), which causes bunchy top disease in bananas, were collected in field surveys on seven islands in Okinawa Prefecture, Japan. From 44 banana samples, one isolate from each island was selected, and the DNA-1 and DNA-3 components were sequenced. Analysis of the major common region of DNA-1 showed that BBTV in Okinawa belongs to the Asian group of BBTV. DNA-1 and DNA-3 analysis revealed that Okinawan BBTV had a closer relationship with isolates from Taiwan and the Philippines than with some isolates from China and Vietnam. All the Okinawan BBTV isolates had high homology in the nucleotide sequences of DNA-1 and DNA-3 (%) because of a single, recent BBTV invasion of this area.The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB108449 – AB108458 相似文献
445.
Md. Manjurul Haque Akihiro Yamazaki Shinji Tsuyumu 《Journal of General Plant Pathology》2005,71(2):133-138
The PhoP-PhoQ two-components regulatory system is involved in the pathogenesis of animal, plant, and insect pathogenic bacteria in response to various environmental factors. To elucidate how this system contributes to the plant pathogenesis of Erwinia chrysanthemi 3937 (Ech 3937), marker-exchanged mutants of phoP and phoQ were constructed. Their role in the regulation of a major virulent factor, pectate lyase (Pel), in response to various organic acids was then tested. These mutants synthesized more Pel than did the wild type in the medium containing acetate or citrate as the sole source of carbon, but they synthesized less Pel than did the wild type in pyruvate or malate as the sole source of carbon. Synthesis of Pel did not differ in succinate, fumarate, or glycerol from the wild type. The phoP and phoQ mutants grown and resuspended in acetate or citrate also caused more maceration, and the wild type pretreated in pyruvate or malate caused more maceration than did the mutants. The level of intracellular acetyl-coenzyme A (acetyl-CoA) almost paralleled the synthesis of Pel in the wild type and in the mutants of the phoP and phoQ. These results suggested that acetyl-CoA may be involved in regulation of Pel synthesis through two-independent regulatory cascades via the PhoP-PhoQ system (in an opposite manner) in response to acetate/citrate and pyruvate/malate. However, ackA and pta genes, involved in the synthesis of acetyl-CoA in Escherichia coli, were not expressed as predicted on the basis of the level of acetyl-CoA. Thus there may be an additional regulation or pathway for the synthesis of acetyl-CoA in Ech 3937. 相似文献
446.
Harukuni Horita Robert J. McGovern Tsutomu Komatsu Shinji Yasuoka 《Journal of General Plant Pathology》2005,71(4):247-252
Inoculum density, temperature, leaf age, and wetness duration were evaluated for their effects on the development of black streak (Itersonilia perplexans) on edible burdock (Arctium lappa L.) in a controlled environment. The effect of relative humidity (RH) on ballistospores production by I. perplexans was also evaluated. Symptoms of black streak on leaves increased in a linear fashion as the inoculum density of I. perplexans increased from 102 to 106 ballistospores/ml. Rugose symptoms on young leaves were observed at densities of ≥104 ballistospores/ml. Disease severity of I. perplexans in relation to leaf age followed a degradation curve when the leaves were inoculated with ballistospores. Disease severity was high in newly emerged leaves up to 5 days old, declined as leaf age increased to 29 days, and was zero when leaf age increased from 30 to 33 days. Disease development of edible burdock plants exposed to ballistospores of I. perplexans was evaluated at various combinations of temperature (10°, 15°, 20°, 25°C) and duration of leaf wetness (12, 24, 36, 48, and 72 h). Disease was most severe when plants were in contact with the ballistospore sources at 15° or 20°C. The least amount of disease occurred at 25°C regardless of wetness duration. Ballistospores required 24–36 h of continuous leaf wetness to cause visible symptoms by infection on edible burdock. Ballistospores production in infected lesions required at least 95.5% RH. 相似文献
447.
Atsushi Ishii Keita Yamaji Yoshinobu Uemoto Nanae Sasago Eiji Kobayashi Naohiko Kobayashi Tamako Matsuhashi Shin Maruyama Hirokazu Matsumoto Shinji Sasazaki Hideyuki Mannen 《Animal Science Journal》2013,84(10):675-682
Fatty acid composition is one of the important traits in beef. The aim of this study was to identify candidate genomic regions for fatty acid composition by genome‐wide association study with 50 K single nucleotide polymorphism (SNP) array in Japanese Black cattle. A total of 461 individuals and 40 657 SNPs were used in this study. We applied genome‐wide rapid association using mixed model and regression (GRAMMAR) and genomic control approaches to estimate the associations between genotypes and fatty acid composition. In addition, two SNPs in fatty acid synthase (FASN) (T1952A) and stearoyl‐CoA desaturase (SCD) (V293A) genes were also genotyped. Association analysis revealed that 30 significant SNPs for several fatty acids (C14:0, C14:1, C16:1 and C18:1) were located in the BTA19 FASN gene located within this region but the FASN mutation had no significant effect on any traits. We also detected one significant SNP for C18:1 on BTA23 and two SNPs for C16:0 on BTA25. The region around 17 Mb on BTA26 harbored two significant SNPs for C14:1 and SNP in SCD in this region showed the strongest association with C14:1. This study demonstrated novel candidate regions in BTA19, 23 and 25 for fatty acid composition. 相似文献
448.
Takahiro Nishimaki Takayuki Ibi Yoshihiro Tanabe Yoshiyuki Miyazaki Naohiko Kobayashi Tamako Matsuhashi Takayuki Akiyama Emi Yoshida Kazumi Imai Mayu Matsui Keiichi Uemura Naoto Watanabe Tatsuo Fujita Yosuke Saito Tomohiko Komatsu Takahisa Yamada Hideyuki Mannen Shinji Sasazaki Tetsuo Kunieda 《Animal Science Journal》2013,84(8):585-591
Japanese Black cattle are at risk for genetic homogeneity due to intensive use of a few sires. Therefore, assessment of the actual genetic diversity of this breed is important for future breeding plans. In the present study, we investigated the genetic diversity within and among eight subpopulations of Japanese Black cattle using 52 microsatellite markers. The parameters for genetic diversity of Japanese Black cattle were comparable to those of other cattle breeds, suggesting that the relatively high genetic diversity of the breed. However, upon comparison among the eight subpopulations, the Hyogo subpopulation showed markedly low genetic diversity. The results of the pairwise FST values, phylogenetic network and structure analysis indicated that the Hyogo population has remarkably high level of genetic differentiation from other populations, while Yamagata, Niigata, Hiroshima and Kagawa populations have low levels of genetic differentiation. Furthermore, multidimensional scaling plots indicated that individuals in some subpopulations were separated from individuals in the other subpopulations. We conclude that while the overall genetic diversity of Japanese Black cattle is still maintained at a relatively high level, that of a particular subpopulation is significantly reduced, and therefore the effective population size of the breed needs to be controlled by correct mating strategies. 相似文献
449.
Tetsuya Sano Satoru Miura Hitomi Furusawa Shinji Kaneko Takahiro Yoshida Takashi Nomura Seiji Ohara 《Journal of Wood Science》2013,59(4):307-320
To evaluate the characteristics of wood ash as fertilizer, composition of inorganic elements and the leaching behavior were studied. The leaching behavior was evaluated by three leaching methods using different solvents (water, hydrochloric acid, and acetic acid: Japanese leaching test Nos. 18 and 19 and modified toxicity characteristic leaching procedure prescribed by the US Environmental Protection Agency). The ash composition varied according to raw materials for fuel and ash collection systems. Concentration of Na, Al, Si, and V became higher in bark ashes while that of K became higher in wood ashes. Pb, Cd, Se, and Zn were more volatile and enriched in fly ashes. Of the nutrient elements, K showed high water solubility and its phytoavailability also appeared high, although the amount of water-soluble K was low in bark ash. Ca and Mg had intermediate solubility while P was less soluble in both water and acetic acid. The amount of hazardous substances having leached was low for most, but not all the ashes, in terms of Pb, Cr and As. Nevertheless, the phytoavailability of these hazardous substances after their application to the forest appeared low, due to their amphoteric leaching behavior and the acidity of Japanese forest soils. 相似文献
450.
Various types of wood-based boards were analyzed for deterioration after being exposed to an outdoor environment for 5 years in Tsukuba, Japan. In phenol–formaldehyde resin bonded particleboard (PB(PF)) and aspen oriented strand board (OSB(aspen)), longer exposure caused a greater reduction in the modulus of rupture and internal bond strength, an increase in the coefficients of variation, and a decrease in 95 % lower tolerance limit at the 75 % confidence level (95TL). Nail-head pull-through and lateral nail resistance were also reduced by outdoor exposure, but their coefficients of variation and 95TL were not significantly affected. In contrast, methylene diphenyl diisocyanate bonded medium density fiberboard (MDF(MDI)) only showed a slight deterioration of these properties even after 5-year exposure, and the coefficients of variation and 95TL hardly changed. After 5-year exposure, the retention of shear load in one-plane at relative displacement of 1.0 mm was high in MDF(MDI) and OSB(aspen) at 93.5 and 78.5 %, respectively, but low in PB(PF) at 41.1 %. As with PB(PF), OSB(aspen) also showed a sharp decrease in the modulus of rupture and internal bond strength, but only slightly reduced shear load in one-plane. 相似文献