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The carcass composition of crossbred Japanese Black × Limousin F2 cattle was examined in order to find an accurate carcass composition equation. The test animals included 17 steers and 17 heifers. The 28 image measurements from the area encircling the vertical line to the thoracic vertebra and the line from the thoracic vertebra between the sixth and seventh rib‐bones were measured by computer image analysis. The relationships between the 29 parameters that added the carcass left side weight of the animal and the carcass composition were suggested. The carcass composition included muscle weight, muscle ratio, fat weight and fat ratio. The carcass composition from steers was estimated by an equation composed of these three or four parameters (R2 = 90.80%, 79.30%, 90.75% and 73.70%, respectively). The selected parameters were measured without cutting the thoracic vertebra. The carcass composition from heifers was estimated by an equation composed of two to four parameters (R2 = 96.15%, 90.98%, 93.60% and 88.22%, respectively). The parameters for the estimation of the muscle and fat weight, and muscle and fat ratio are very similar. Furthermore, the equations using the parameters could estimate the carcass composition from the Japanese Black × Limousin cattle resource population.  相似文献   
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Canine melanoma is one of the most important diseases in small animal medicine. Protein phosphatase 2A (PP2A), a well conserved serine/threonine phosphatase, plays a critical role as a tumor suppressor. SET/I2PP2A is an endogenous inhibitor for PP2A, which directly binds to PP2A and suppresses its phosphatase activity. Elevated SET protein levels have been reported to exacerbate human tumor progression. The role of SET in canine melanoma, however, has not been understood. Here, we investigated the potential therapeutic role for SET inhibitors in canine melanoma. The expression of SET protein was observed in 6 canine melanoma cell lines. We used CMeC-1 cells (primary origin) and CMeC-2 cells (metastatic origin) to generate cell lines stably expressing SET-targeting shRNAs. Knockdown of SET expression in CMeC-2, but not in CMeC-1, leads to decreased cell proliferation, invasion and colony formation. Phosphorylation level of p70 S6 kinase was decreased by SET knockdown in CMeC-2, suggesting the involvement of mTOR (mammalian target of rapamycin)/p70 S6 kinase signaling. The SET inhibitors, OP449 and FTY720, more effectively killed CMeC-2 than CMeC-1. We observed PP2A activation in CMeC-2 treated with OP449 and FTY720. These results demonstrated the potential therapeutic application of SET inhibitors for canine melanoma.  相似文献   
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ABSTRACT: The gut and gut contents of ayu Plecoglossus altivelis caught in the Ohta River in Hiroshima prefecture, Japan were examined. Relative intestine length (intestine length/body length) was almost constant. Except for relative intestine length, characteristics of the gut of wild ayu were not significantly different from those of cultured ayu. The height of intestinal folds increased and their width declined from stomach to anus. Cyanobacteria ( Homoeathrix sp. and Calothrix sp.) and diatoms ( Cymbella sp., Gomphonema sp., Melosira sp., Navicula sp., and Synedra sp.) were well digested during passage through the gut despite a lack of apparent destruction. In contrast, green algae ( Dictyosphearium sp., Coelastrum sp., and Pediastrum sp.) exhibited little degradation. The pH of stomach contents ranged from 2.8 to 7.4 (mean ± SD = 4.1 ± 1.0), whereas that of the posterior intestine was 7.0–8.5 (7.9 ± 0.4). Gut contents of wild ayu increased with bodyweight, and were more than threefold greater than those of cultured ayu, suggesting that wild ayu compensate for low nutrient content of algae through the continuous ingestion of large quantities of feed organisms.  相似文献   
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ABSTRACT: A series of experiments were conducted to examine the effects of salinity, aeration and light intensity on oil globule absorption, feeding incidence, and growth and survival of early-stage Epinephelus coioides larvae. Newly hatched larvae were transferred to 40-L aquaria at a density of 1500 individuals/aquarium. Larvae were exposed to different levels of aeration (0 mL/min per L, 0.62 mL/min per L, 1.25 mL/min per L, 2.50 mL/min per L, or 3.75 mL/min per L); salinity (8 ppt, 16 ppt, 24 ppt, 32 ppt, or 40 ppt); and light intensity (0 lx, 120 lx, 230 lx, 500 lx, or 700 lx) for 4–6 days. Twenty larvae were sampled daily at 11:00 hours to measure for total length (TL), oil globule volume, and feeding incidence. Survival rates were determined by counting the total number of larvae remaining in each aquarium at the end of the experiment. Significantly higher survival rates ( P   <  0.05) were observed at aeration levels of 0.62 mL/min per L and 1.25 mL/min per L, at salinity levels of 16 ppt and 24 ppt, and at light intensities of 500 lx and 700 lx. The influence of aeration level, salinity and light intensity on oil globule absorption, feeding incidence, and growth and survival of early-stage grouper larvae are discussed.  相似文献   
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The aim of the present study was to examine the change in plasma insulin‐like growth factor‐1 (IGF‐1) concentration with early growth, changes of bodyweight (BW) and relative dairy gain (RDG) in the pre‐ (PRW) and postweaning periods (POW) in Japanese beef cattle, and relationships with metabolites. A total of 33 calves, 22 Japanese black, 6 Japanese shorthorn and 5 of their crossbreed were studied. Insulin‐like growth factor‐1 and metabolite (glucose, triacylglycerol, nonesterified fatty acid) levels in the plasma, from jugular vein blood taken every month, were measured along with BW. Insulin‐like growth factor‐1 in POW increased dramatically with increase of BW (P < 0.05), and the correlation was positive at 0.52 (P < 0.01). Glucose levels correlated significantly with BW, RDG and IGF‐1 (P < 0.01). Metabolic required calorie correlated positively with IGF‐1 (P < 0.01). Also, correlations of BW in POW, with BW and RDG in PRW were positive (P < 0.01). Growth in PRW would be influenced by maternal effects, while active self‐secretion of IGF‐1 in POW might contribute to POW growth. These factors suggested that to increase growth in PRW, maintaining enough maternal effect and IGF‐1 level in POW, was important for establishing better growth after weaning.  相似文献   
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An endophytic actinomycete, Streptomyces sp. R-5, which had been isolated from a field-grown rhododendron plant, was used to protect rhododendron seedlings in tissue culture from Pestalotia disease caused by Pestalotiopsis sydowiana. R-5 had intense antagonistic activity against P. sydowiana without adversely affecting the seedlings in glass flasks. A suspension of R-5 was spread on the surface of the multiplication medium in glass flasks in which seedlings were growing. Ten days later, the 4th upper leaf of seedlings was inoculated with P. sydowiana and incubated for 14 days. In controls untreated with R-5, substrate mycelia of P. sydowiana grew on all leaves and stems above and below the 4th leaf within 2–3 days of inoculation. Such growth resulted in the wilting death of 54% of seedlings by 14 days. In contrast, only the inoculated leaves turned brown in ca. 90% of seedlings growing on medium treated with R-5. None of these seedlings died. Thus, treatment of the medium surface with R-5 efficiently protects the seedlings from infection by P. sydowiana. Scanning electron microscopy revealed that substrate mycelia of R-5 grew on and beneath the cuticle of leaves of the treated seedlings. Fluorescent microscopy showed that R-5 was also inside the leaves. Received 8 June 2001/ Accepted in revised form 4 July 2001  相似文献   
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