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41.
This study was conducted to determine the antiproliferative activity of 24 Korean wild vegetables. The methanol extracts of these wild vegetables were used against lung, breast, colon and gastric cancer cells, and the results were assessed by MTT assay. It was found that at the extract concentration of 400 mgL−1 14 plants exercised antiproliferative activity over 80% against the lung cancer cells, one plant among six—against breast cancer cells, and two plants among six—against colon cancer cells, respectively. Eighteen wild vegetables had the hyperplasia inhibition activity against gastric cancer cells over 23.6% at all extract concentrations, however, only six plants had the antiproliferative activity over 80% in 600 mgL−1. It was found that the extracts from Youngia sonchifolia, Synurus deltoides, Syneilesis palmata, and Cephalonoplos segetum, in concentration of 400 mgL−1 inhibited the hyperplasia of lung cancer cells over 95% and Angelica gigas—both lung and colon cancer cells over 95%. In conclusion, the studied wild vegetables’ methanol extracts possess dose dependent antiproliferative properties, based on their bioactive compounds, mainly polyphenols, but some of them as Hypericum ascyron against lung cancer are not effective and even course harm.  相似文献   
42.
It is important to estimate the productive efficiencies of industries, especially the fishing industry, in order to determine policies that can improve business conditions. In this study, the productive efficiency of the sandfish coastal gillnet fishery on the east coast of Korea has been estimated using stochastic frontier analysis (SFA). A translog production function wherein the inefficiency was represented by a truncated-normal distribution was established; the output variable was the trip production quantity, the input variables were physical production factors directly related to the fishing activities of vessels, such as tonnage, horsepower, and the number of employed fishers. The average productive efficiency of the sample was 0.59 [0.40–0.79], which implied that productive inefficiency occurs in sandfish coastal gillnet vessels. Moreover, it was verified that there are no differences among the average productive efficiencies of fishing vessels of different tonnages.  相似文献   
43.
In 2008, Korean flounder (Glyptocephalus stelleri) was designated by the Korean Ministry for Food, Agriculture, Forestry and Fisheries as a species for restoration in the coastal waters of Korea. However, there are currently no regulations regarding the minimum landed size of flounder, or the minimum legal mesh size used by the coastal gillnet and trammel net fisheries. Selectivity experiments for gillnets and trammel nets were conducted using commercial vessels in several areas off the eastern coast of Korea between October 2006 and June 2009. The selectivity analysis required an adaption of the SELECT method because trammel net mesh sizes were altered part-way through the experiment. Gillnet and trammel net selectivity was best described using a bi-modal selection curve. The two gears were found to have different selection curves for a given mesh size. The length of maximum retention was similar for the two gears, but the selection curve of the trammel net was substantially wider than that of the gillnet. For the largest size of mesh used in the commercial fishery (8.5 cm stretched), 50% relative retention was estimated to occur at a length of 20.4 cm for the trammel net, and 22.5 cm for the gillnet. In comparison, the length of 50% maturity for this species is approximately 26 cm. As there are currently no size restrictions on landings of Korean flounder, these results suggest that use of these gears may pose a serious threat to local stocks of this species.  相似文献   
44.
Three different dietary additives were evaluated based on growth performance, innate immune responses and disease resistance in juvenile Amur catfish Silurus asotus. Four diets were prepared by supplementing 0.4% Song-gang® stone (SG), 0.05% Yucca meal (YM), 0.05% β-glucan (BG) in combination with 0.04% SG and 0.05% BG (SG + BG) to a basal commercial diet (control; CONT). Triplicate groups of fish averaging 4.95 ± 0.05 g were fed one of the test diets between 3 and 5% body weight for 8 weeks. At the end of the feeding trial, weight gain, specific growth rate, feed efficiency and protein efficiency ratio of fish fed SG and SG + BG were significantly higher than those of fish fed the BG and CONT diets (P < 0.05). Lysozyme activity in fish fed the SG, YM, and SG + BG diets was significantly higher than those of fish fed the CONT diet. Super oxide dismutase (SOD) activity was significantly higher among fish fed the SG, YM, BG and SG + BG diets than fish fed the CONT diet. After 14 days challenge test with Edwardsiella tarda, cumulative survival rates of fish fed the SG and SG + BG diets were significantly higher than those of fish fed the BG and CONT diets. Results revealed that dietary SG or SG + BG diets had positive responses over other additives in juvenile Amur catfish. However, Song-gang® stone is proposed to be a cheaper dietary additive contributing 0.04 cents/kg of feed based on economic point of view.  相似文献   
45.
A translucent collagen gel was formed from a transparent acidic solution of red stingray collagen by adjusting to physiological ionic strength and pH in phosphate buffer and then incubating at 25–37°C. During fibril formation from red stingray collagen, the turbidity increased when the NaCl concentration was increased at constant pH and the rate of fibril formation was accelerated by higher pH or lower NaCl concentration. The T m of red stingray collagen fibrillar gel was estimated as 44.3 ± 3.5°C, which was higher than that of the collagen solution, 33.2°C. In addition, red stingray collagen gel maintained its shape without melting and was suitable for culture of mouse stromal cells at 37°C.  相似文献   
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Object recognition memory and contextual fear conditioning task performance in adult C57BL/6 mice exposed to cranial fast neutron irradiation (0.8 Gy) were examined to evaluate hippocampus-related behavioral dysfunction following acute exposure to relatively low doses of fast neutrons. In addition, hippocampal neurogenesis changes in adult murine brain after cranial irradiation were analyzed using the neurogenesis immunohistochemical markers Ki-67 and doublecortin (DCX). In the object recognition memory test and contextual fear conditioning, mice trained 1 and 7 days after irradiation displayed significant memory deficits compared to the sham-irradiated controls. The number of Ki-67- and DCX-positive cells decreased significantly 24 h post-irradiation. These results indicate that acute exposure of the adult mouse brain to a relatively low dose of fast neutrons interrupts hippocampal functions, including learning and memory, possibly by inhibiting neurogenesis.  相似文献   
49.
Seo KS  Lim JY  Yoo HS  Bae WK  Park YH 《Veterinary microbiology》2005,106(3-4):225-233
Vancomycin-resistant enterococci (VRE) have emerged as an important nosocomial pathogen. Since 1989, a rapid increase in the incidence of enterococcal bacteremia and endocarditis by VRE has been reported. The use of avoparcin in animal husbandry is reportedly associated with the appearance of VRE. In this study, a multiplex polymerase chain reaction (PCR) method was established to detect and differentiate resistant types of enterococci, which specifically amplify the four van genes that encode vancomycin resistance elements. Using this method, we investigated the incidence rates and types of VRE from two types of farms: those that had used avoparcin and those that had not used avoparcin. A total of 1091 animal fecal samples were collected from 70 pig farms and 32 poultry farms. A total of 425 enterococci were isolated from the fecal samples. Among the 425 isolates, six showed a pattern of high-level vancomycin resistance (Minimal Inhibitory Concentration, MIC: 64-256 microg/ml). Out of six high-level VRE, three were isolated from poultry farms that had used avoparcin and three were not. The six high-level VRE harbored the vanA gene. Sixty-seven of 425 isolates that showed a pattern of low-level vancomycin resistance (MIC: 4-8 microg/ml) were associated with the presence of vanC-1 or vanC-2/3 gene. We also performed a repetitive extragenic palindromic PCR (rep-PCR) method to compare the genetic relatedness between the high-level VRE of six animal isolates and 31 human isolates. None of the animal isolates had a similar rep-PCR pattern as the human isolates but similarities between human VRE isolates were observed.  相似文献   
50.
Although bacteria use different iron compounds in vitGro, the possibility that microbes distinguish between these iron sources during infection has hitherto not been examined. We applied stable isotope labeling to detect source-specific iron by mass spectrometry and show that Staphylococcus aureus preferentially imports heme iron over transferrin iron. By combining this approach with computational genome analysis, we identified hts (heme transport system), a gene cluster that promotes preferred heme iron import by S. aureus. Heme iron scavenging by means of hts is required for staphylococcal pathogenesis in animal hosts, indicating that heme iron is the preferred iron source during the initiation of infection.  相似文献   
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