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1.
Kunio Shirakihara Masahiko Yoshida Machiko Nishino Yoshimi Takao Kouichi Sawada 《Fisheries Science》2001,67(3):430-435
SUMMARY: The vertical distribution of dwarf ayu Plecoglossus altivelis altivelis in the pelagic waters of Lake Biwa was evaluated from June to September in 1995–97 from eight acoustic surveys using a quantitative echosounder. In each survey, echoes from a depth range of 3 m to the sea bottom were collected at a station every 2.7 s for 24 h together with measurements of vertical profiles of water temperature and chlorophyll-a. The ayu's echoes were identified using an underwater video camera. The ayu were observed near the maximum chlorophyll-a depth and above the thermocline. Their density was highest at depths of 4–11 m with 2–4 individuals/m 3 and was almost zero below 20 m. Echo signs were recorded as having a frequent duration of more than 1 h at night, whereas were of a shorter duration in the day. The fish stay in the epilimnion during the day without any clear vertical migration, but are distributed more uniformly at night. The advantages of remaining in the epilimnion are discussed in terms of food availability and predator avoidance. 相似文献
2.
F Urayama T Sato H Shibuya W Shirai M Matsutani R Yamazaki 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2001,63(11):1249-1252
An apocrine adenocarcinoma was observed in the subcutis of the abdomen of golden hamster. Histologically, the tumor cells irregularly formed multiple layers of cysts and some detached cells were presented in the cystic space. PAS stain with alpha-amylase digestion revealed PAS-positive alpha-amylase-resistant granules in the cytoplasm. Immunohistochemically, cytokeratin was demonstrated in the tumor cells. By electron microscopy, the tumor cells had an oval nucleus with invagination, abundant cytoplasmic organelles and microvilli protruding into the intercellular spaces. 相似文献
3.
Fluid accumulation in mouse ligated intestine inoculated with the vascular permeability factor produced by Bacillus cereus. 总被引:1,自引:0,他引:1
K Shinagawa K Sato H Konuma N Matsusaka S Sugii 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1991,53(2):167-171
Partially purified vascular permeability (VP) factor (VPF) of Bacillus cereus induced fluid accumulation in the ligated intestinal loops of mouse (MIL) and rabbit (RIL), suggesting that the VP activity may correlate with fluid accumulation in ligated intestinal loops of these animals. Fluid accumulation was observed at 6-8 hr in 55-67% of mouse intestinal loops inoculated with 40-50 immunodiffusion units (IDU) of partially purified VPF, whereas it was found at 2 hr in all loops with 400-600 IDU of partially purified VPF. In rabbit intestinal loops with 120-190 IDU of partially purified VPF, fluid accumulation was observed at 6 hr. From these findings, VPF produced by B. cereus can be easily detected in both MIL and RIL. The intestinal tissue of mouse intestinal loops was histopathologically damaged at different concentrations of the VPF to induce fluid accumulation. With 50 IDU of partially purified VPF, severe edema was found in the laminia proprial layer and submucosa. With 600 IDU of partially purified VPF, on the other hand, severe necrosis in the surface epithelium of villus and laminia proprial layer, and hyperemia in the submucosa were observed, suggesting that partially purified VPF may be cytotoxic and/or intestinecrotic. 相似文献
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6.
Familial Congenital Methemoglobinemia in Pomeranian Dogs Caused by a Missense Variant in the NADH‐Cytochrome B5 Reductase Gene
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H. Shino Y. Otsuka‐Yamasaki T. Sato K. Ooi O. Inanami R. Sato M. Yamasaki 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):165-171
Background
In veterinary medicine, congenital methemoglobinemia associated with nicotinamide adenine dinucleotide (NADH)‐cytochrome b5 reductase (b5R) deficiency is rare. It has been reported in several breeds of dogs, but little information is available about its etiology.Objectives
To analyze the NADH‐cytochrome b5 reductase gene, CYB5R3, in a Pomeranian dog family with methemoglobinemia suspected to be caused by congenital b5R deficiency.Animals
Three Pomeranian dogs from a family with methemoglobinemia were analyzed. Five healthy beagles and 5 nonrelated Pomeranian dogs without methemoglobinemia were used as controls.Methods
Methemoglobin concentration, b5R activity, and reduced glutathione (GSH) concentration were measured, and a turbidity index was used to evaluate Heinz body formation. The CYB5R3 genes of the affected dog and healthy dogs were analyzed by direct sequencing.Results
Methemoglobin concentrations in erythrocytes of the affected dogs were remarkably higher than those of the control dogs. The b5R activity of the affected dogs was notably lower than that of the control dogs. DNA sequencing indicated that this Pomeranian family carried a CYB5R3 gene missense variant (ATC→CTC at codon 194) that resulted in the replacement of isoleucine (Ile) by leucine (Leu).Conclusions and Clinical Importance
This dog family had familial congenital methemoglobinemia caused by b5R deficiency, which resulted from a nonsynonymous variant in the CYB5R3 gene. This variation (c.580A>C) led to an amino acid substitution (p.Ile194Leu), and Ile194 was located in the proximal region of the NADH‐binding motif. Our data suggested that this variant in the canine CYB5R3 gene would affect function of the b5R in erythrocytes. 相似文献7.
8.
Oriental persimmon (Diospyros kaki) originated in Eastern Asia, and many indigenous cultivars have been developed in China, Japan, and Korea. These cultivars are classified into four groups based on their natural astringency loss on the tree and seed formation: pollination-constant non-astringent (PCNA), pollination-variant non-astringent (PVNA), pollination-constant astringent (PCA), and pollination-variant astringent (PVA). PCNA is the most desirable type because the fruit can be eaten without any postharvest treatment; therefore, one of the goals of our persimmon breeding programs is to release superior PCNA cultivars. The PCNA genotype is recessive to the other three non-PCNA genotypes, and PCNA-type F1 offspring are obtained exclusively from crosses among PCNA genotypes. Moreover, the number of superior PCNA cross-parents have been limited. In the late 1980s, inbreeding depression became obvious, especially in terms of fruit size, tree vigor, and productivity. To mitigate the inbreeding, a backcross program using PCNA [(non-PCNA × PCNA) × PCNA] was started in 1990. This process, however, was inefficient because only 15% of the offspring were PCNA, and all offspring had to be grown to the fruiting stage. Therefore, molecular markers linked to the PCNA locus were developed for discriminating PCNA offspring. A molecular marker linked to Chinese PCNA has also been developed. 相似文献
9.
Yukako Tokutake Marcin Taciak Kan Sato Masaaki Toyomizu Motoi Kikusato 《Animal Science Journal》2021,92(1):e13604
Peptide transporter 1 (PepT1) is a transporter responsible for absorbing dipeptide and tripeptide in enterocytes and is upregulated by dipeptide in mammals. It has not been certain whether intestinal PepT1 expression is responsive to dipeptides in chickens because of the lack of in vitro study using the cultured enterocytes. This study established a primary culture model of chicken intestinal epithelial cells (IECs) in two-dimensional monolayer culture using collagen gel by which the response of chicken PepT1 gene expression to dipeptide stimuli was evaluated. The cultured chicken IECs showed the epithelial-like morphology attached in a patch-manner and exhibited positive expression of cytokeratin and epithelial cadherin, specific marker proteins of epithelial cells. Moreover, the chicken IECs exhibited the gene expression of intestinal cell type-specific marker, villin1, mucin 2, and chromogranin A, suggesting that the cultured IECs were composed of enterocytes as well as goblet and enteroendocrine cells. PepT1 gene expression was significantly upregulated by synthetic dipeptide, glycyl-l-glutamine, in the cultured IECs. From the results, we herein suggested that dipeptide is a factor upregulating PepT1 gene expression in chicken IECs. 相似文献
10.
Sward characteristics,nutritive value and choice by cattle of conterminous monocultures of centipedegrass (Eremochloa ophiuroides) and bahiagrass (Paspalum notatum)
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Masahiko Hirata Toshiro Okuma Yuichiro Tanaka Manabu Tobisa 《Animal Science Journal》2016,87(5):674-680
In south‐western Japan, centipedegrass (Eremochloa ophiuroides; CG) offers a novel option for a warm‐season perennial for grazing use in areas where bahiagrass (Paspalum notatum; BG) can be grown. However, the potential of CG as a forage has not been fully explored because of the short history as a forage crop. We conducted four experiments to evaluate CG (cv. TifBlair) in comparison with BG (cv. Pensacola) in terms of sward characteristics, nutritive value and choice by animals. In each experiment, four Japanese Black cows (Bos taurus) were individually allowed to graze conterminous monocultures of CG and BG (5 × 10 m each) for 30 min. Irrespective of regrowth durations and fertilizer rates, CG was consistently shorter, leafier and denser, contained lower acid detergent fiber and cellulose, and was preferred or equally selected by cows, as compared with BG. Furthermore, CG maintained sufficient levels of crude protein (80–89 g/kg DM) to ensure voluntary intake of ruminant animals under extended regrowth? and without fertilizer, whereas BG failed to do so (65 g/kg DM). CG provided higher digestible dry matter than BG when crude protein concentration exceeded 86 g/kg DM. The results indicate advantages of CG as a forage. 相似文献