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551.
552.
The aim of the present study was to investigate the protective effects of Ganoderma lucidum polysaccharide (GLPS) against carbon tetrachloride (CCl4)-induced hepatotoxicity in vitro in common carp. Precision-cut liver slices (PCLSs), which closely resemble the organ from which they are derived, were employed as an in vitro model system. GLPS (0.1, 0.3, and 0.6 mg/ml) was added to PCLS culture system before the exposure to 12 mM CCl4. The supernatants and slices were collected to detect molecular and biochemical responses to CCl4 and PCLS treatments. The levels of CYP1A, CYP3A, and CYP2E1 were measured by ELISA; the mRNA expressions of TNF-α, IL-1β, IL-6, and iNOS were determined by RT-PCR; and the relative protein expressions of c-Rel and p65 were analyzed by western blotting. Results showed that GLPS inhibited the elevations of the marker enzymes (GOT, GPT, LDH) and MDA induced by CCl4; it also enhanced the suppressed activity of antioxidant enzymes (SOD, CAT, GSH-Px, T-AOC). The treatment with GLPS resulted in significant downregulation of NF-κB and inflammatory cytokine mRNA levels and significant decreases in the hepatic protein levels of CYP1A, CYP3A, and CYP2E1. These results suggest that GLPS can protect CCl4-induced PCLS injury through inhibiting lipid peroxidation, elevating antioxidant enzyme activity, and suppressing immune inflammatory response.  相似文献   
553.
554.
A highly viscous polysaccharide solution was extracted from Gagome Kjellmaniella crassifolia in 20°C water. The eluted sugar concentration was 0.16%, and the extracted carbohydrates consisted of fucoidan, laminaran, and alginate at an approximately ratio of 8.2:0.8:1.0. An increase in the extraction temperature resulted in a less viscous solution, even though the amount of eluted sugar was higher than that obtained at a lower temperature. The most viscous extraction solution was obtained at a neutral pH, with a more acidic or alkaline extraction solution being a less viscous. When the highly viscous polysaccharide solution was heated, the viscosity decreased markedly with increasing temperature. The viscosity of the polysaccharide solution increased after dialysis against water and decreased with the addition of either KCl or NaCl. However, the viscosity was recovered to previous levels by following re-dialysis against water. The removal of divalent cations by EDTA and the re-addition using CaCl2 or MgCl2 also caused reversible changes to the viscosity. These characterizations will be useful for widespread applications of viscous K. crassifolia polysaccharides.  相似文献   
555.
We investigate the effect of Al on K+ uptake by rice roots. Potassium-38 (38K), a positron emitting nuclide (the half-life: 7.61 min), was used to trace K+ behavior. When a rice root was treated with 10μM Al for 24 h, the uptake of 38K in the root was increased in the range of 1 to 2 cm from the root tip compared with that of the control sample. Because the root continued to grow without showing any damage of plasma membrane during the Al treatment, it was suggested that the 38K uptake was not occurred through diffusion into the cells. The uptake of 38K in both treatments, with/without Al, was decreased by VO43- (inhibitor of H+-ATPase on plasma membrane) and DNP (H+ ionophore) treatment, which suggested that the K+ uptake was performed through an active transport, such as H+:K+ transport or H+ gradient promoted by an Al treatment.  相似文献   
556.
Canine degenerative myelopathy (DM) is a progressive neurodegenerative disease of the spinal cord. The diagnosis is based on the observation of clinical signs, genetic testing, and exclusion of other spinal cord diseases, and a definitive diagnosis of DM can only be confirmed by postmortem histopathological findings. The aim of this study was to investigate the diagnostic ability of diffusion tensor imaging (DTI) for DM. Eight DM-affected Pembroke Welsh Corgis, thirteen dogs with thoracolumbar intervertebral disk herniation (IVDH), and six healthy control dogs were included. All dogs were scanned using a 3.0-T MRI system. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values were calculated for each intervertebral disk level slice between T8–T9 and L2–L3 intervertebral disk levels, and the entire area of the thoracolumbar spinal cord between T8–T9 and L2–L3 intervertebral disk levels (T8–L3 region). The ADC and FA values of the T8–L3 region were significantly lower in the DM group than in the IVDH group. The ADC values for the T8–L3 region had a moderate negative correlation with clinical duration (rs= −0.723, P=0.043); however, the FA values of other intervertebral disk levels and T8–L3 region had no correlation with clinical durations. The measurement of DTI indices can be used to quantitatively assess neurodegeneration and may have diagnostic value for DM. In particular, the ADC value of the T8–L3 region may aid in making a non-invasive premortem diagnosis of DM.  相似文献   
557.
Fisheries Science - The brittle star Ophiura sarsii with a disc diameter (DD) of less than 9 mm is an important prey item for flathead flounder Hippoglossoides dubius in Funka...  相似文献   
558.
The risk of norovirus food poisoning from oyster consumption can be minimized by consumers, as thorough cooking can destroy norovirus. This paper uses data from 23 prefectures in Japan during 1970–2010 to examine how the demand for oysters responds to this manageable risk. We find that the incidence rate of norovirus has no effect on the price of oysters in prefectures that specialize in oysters for cooking, whereas it has significant negative impacts in prefectures that produce oysters to be eaten raw. These results indicate that consumers respond differently to manageable and non-manageable risks.  相似文献   
559.
Kasai  Akihide  Takada  Shingo  Yamazaki  Aya  Masuda  Reiji  Yamanaka  Hiroki 《Fisheries Science》2020,86(3):465-471
Fisheries Science - The environmental DNA (eDNA) technique is a convenient and powerful tool to detect rare species. Knowledge of the degradation rate of eDNA in water is important for...  相似文献   
560.
Fisheries Science - Predicting the outbreak of disease is essential when managing shrimp farms. Acute hepatopancreatic necrosis disease (AHPND) caused by Vibrio parahaemolyticus is a serious...  相似文献   
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