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101.
Woong Yoon Jung Min Ryu Min Young Lee Yong Ju Moon Sang Hun Lee Jae Hong Park Seung Pil Yun Min Woo Jang Sung Su Park Ho Jae Han 《Journal of veterinary science (Suw?n-si, Korea)》2010,11(3):185-189
Micropigs are the most likely source animals for xenotransplantation. However, an appropriate method for evaluating the lung of micropigs had not been established. Therefore, this study was performed to evaluate the feasibility of 64-channel multi-detector row computed tomography (MDCT) to measure the diameter of the pulmonary arteries and the lung volume in micropigs. The mean diameters of the trachea, and left and right bronchi were 1.6 ± 0.17, 1.18 ± 0.14, and 1.1 ± 0.11 cm, respectively. The mean diameters of the main, right, and left pulmonary arteries were 1.38 ± 0.09, 1.07 ± 0.26, and 0.98 ± 0.13 cm and the diameters of right, left, and common inferior pulmonary veins were 0.97 ± 0.20, 0.76 ± 0.20, and 1.99 ± 0.26 cm, respectively. The mean lung volume was 820.3 ± 77.11 mL. The data presented in this study suggest that the MDCT may be a noninvasive, rapid, and accurate investigational method for pulmonary anatomy in living lung donors. 相似文献
102.
Effect of silicon on growth and salinity stress of soybean plant grown under hydroponic system 总被引:1,自引:0,他引:1
Silicon (Si) is abundant in the soil, yet its role in plant biology has been poorly understood. The role of Si in soybean growth and its effectiveness in salt stress alleviation was investigated. Sodium metasilicate (Na2SiO3) was given as Si source to hydroponically grown soybean (Glycine max (L.) Merr.). The plant growth attributes, i.e. plant height, plant fresh and dry biomass, chlorophyll contents and endogenous gibberellins (GAs) level improved with 2.5 mM Si, while endogenous abscisic acid (ABA) and free proline contents were not affected as compared to control. Sodium chloride (NaCl) significantly decreased growth attributes and endogenous gibberellins levels but markedly enhanced ABA and proline contents of soybean leaves. An addition of Si to salt stressed plants substantially alleviated the adverse effects of NaCl on growth, as it enhanced endogenous gibberellins, while reduced the levels of ABA and proline. GAs analysis of soybean leaves also showed that both early C13 hydroxylation and non C13 hydroxylation pathways of gibberellin biosynthesis were operating in soybean. The major GA biosynthesis pathway was identified as non C13 hydroxylation, which led to the formation of bioactive GA4. Current study suggests that Si application alleviates the detrimental effect of salinity stress on growth and development of soybean. 相似文献
103.
Effect of hydrogen peroxide exposures on mucous cells and lysozymes of gill tissues of olive flounder Paralichthys olivaeceus 下载免费PDF全文
We investigated the effects of hydrogen peroxide on mucous cells and lysozymes in gill tissue of olive flounder. Morphological analysis revealed significant changes in the number of mucous cells after exposure to 300 and 500 mg L ? 1 hydrogen peroxide; however, there was no detectable difference in the 100 mg L ? 1 group. Lysozyme activities declined gradually in the gill mucus, but in contrast activities in serum increased significantly following the completion of treatment. The hepatic c‐ and g‐type lysozyme levels showed significant responses, indicating that the liver is a major lysozyme producer in response to stress condition; however, in the head kidney, there were no significant changes in the g‐type lysozyme level in all the groups, while the only detectable difference with the c‐type gene in the 300 mg L ? 1. While the treatments showed no significant changes compared with the control for either branchial lysozyme, there were significant differences in c‐type lysozyme between the 3rd treatment and 5 day. Taken together, our data indicate that hydrogen peroxide treatment may lead to modulation of the innate immune response of olive flounder; therefore, the application of hydrogen peroxide in a field system will require more attention to dose and timing effects. 相似文献
104.
Hong SY Kim JY Ahn HY Shin JH Kwon O 《Journal of agricultural and food chemistry》2012,60(12):3086-3091
Nitric oxide (NO) produced by endothelial nitric oxide synthase (eNOS) is a fundamental regulator of systemic blood pressure. Ginsenosides from Panax ginseng have been investigated in vitro for the molecular and biochemical mechanisms by which they stimulate NO release in vascular endothelial cells; however, little research has been done to confirm the physiological relevance of these in vitro studies. To address this research gap, the effects of a P. ginseng extract rich in ginsenosides from protopanaxatriol on spontaneously hypertensive rats (SHRs) was examined. Ginseng extract administration stimulated nongenomic Akt-mediated eNOS activation, enhanced NO production, improved vessel wall thickening, and alleviated hypertension in SHRs, confirming the physiological relevance of previous in vitro studies with ginsenosides. 相似文献
105.
VP Dia T Gomez G Vernaza M Berhow YK Chang EG de Mejia 《Journal of agricultural and food chemistry》2012,60(32):7886-7894
Soybean contains constituents that have antinutritional and bioactive properties. Enzymatic hydrolysis and germination can enhance the biological activity of these compounds in soybean. The objective of this study was to investigate the effect of germination, Alcalase (protease) hydrolysis, and their combination on the concentrations of antinutritional and bioactive compounds in Brazilian soybean cultivar BRS 133. A combination of germination and Alcalase hydrolysis resulted in the degradation of Bowman-Birk inhibitor (BBI), Kunitz trypsin inhibitor (KTI), and lunasin by 96.9, 97.8, and 38.4%. Lectin was not affected by any of the processing treatments when compared to nongerminated and nonhydrolyzed soy protein extract. Total isoflavones (ISF) and total saponins (SAP) increased by 16.2 and 28.7%, respectively, after 18 h of germination, while Alcalase hydrolysis led to the reduction of these compounds. A significant correlation was found between concentrations of BBI and KTI, BBI and lunasin, BBI and ISF, KTI and lunasin, KTI and ISF, KTI and SAP, lunasin and ISF, and ISF and SAP. Germination and Alcalase hydrolysis interacted in reducing BBI, ISF, and SAP. This study presents a process of preparing soy flour ingredients with lower concentrations of antinutritional factors and with biologically active constituents, important for the promotion of health associated with soybean consumption. In conclusion, 18 h of germination and 3 h of Alcalase hydrolysis is recommended for elimination of protease inhibitors, while bioactives are maintained by at least 50% of their original concentrations. 相似文献
106.
Chang?Hoon?Lee Sang?Yoon?Kim Maria?B.?Villamil Prabhat?Pramanik Chang?Ok?Hong Pil?Joo?KimEmail author 《Biology and Fertility of Soils》2012,48(4):435-442
Cultivation of green manure plants during the fallow season in rice paddy soil has been strongly recommended to improve soil
properties. However, green manuring may impact greenhouse gas emission, methane (hereafter, CH4) in particular, under the flooded rice cultivation and thus, application of chemical amendments being electron acceptors
can be an effective mitigation strategy to reduce CH4 emissions in irrigated rice (Oryza sativa L.) field amended with green manure. To investigate the effect of iron (Fe) slag silicate fertilizer (hereafter, silicate
fertilizer), which was effective in reducing CH4 emission and increasing rice productivity, in green manure-amended paddy soil, the aboveground biomass of Chinese milk vetch
(hereafter, vetch) was added at rates of 0, 10, 20, and 40 Mg (fresh weight) ha−1 before the application of silicate fertilizer, which was added at rates of 0 and 2.3 Mg ha−1. Silicate fertilization reduced the seasonal CH4 flux by ca. 14.5% and increased rice yield by ca. 15.7% in the control (no vetch application) treatment. However, CH4 production was increased by silicate fertilization in vetch-treated soil particularly at the initial rice growing stage,
which was probably due to the enhanced decomposition of added organic matters by the silicate liming effect. In conclusion,
silicate fertilization is not effective in reducing CH4 production in green manure-amended rice paddy soils and its use should be properly controlled. 相似文献
107.
Water quality and limnology of Korean reservoirs 总被引:2,自引:0,他引:2
Soon-Jin?HwangEmail author Soon-Kuk?Kwun Chun-Gyeong?Yoon 《Paddy and Water Environment》2003,1(1):43-52
Reservoirs are the predominant type of lentic ecosystem in Korea, and they account for a considerable proportion (~59%) of
the agricultural water uses. There are 18,797 reservoirs in Korea; most (~90%) are small (storage capacity <1,000,000 m3), and most provide irrigation water for paddy farming. Characteristics of Korean agricultural reservoirs are high watershed-reservoir
area ratios, shallow depth, unstable hydrodynamics, and eutrophic conditions. Many agricultural reservoirs are relatively
old; 54% of all reservoirs were constructed more than 50 years ago. As a result, they have a considerable amount of organic
matter accumulation on the sediment, which may contribute to the internal loading of nutrients. Deterioration of water quality
and ecosystem health, resulting from cultural eutrophication and harmful algal blooms, are common problems in most Korean
agricultural reservoirs. Environmental considerations about reservoirs, especially their ecological functions, have largely
been ignored in past management plans. Limnology, the multidisciplinary study of lakes and reservoirs, can provide conceptual
models of reservoirs and fundamental information needed to determine causes and potential solutions for environmental stresses.
Problems prevailing in Korean reservoirs, such as cultural eutrophication and harmful algal blooms, are complicated ecosystem-level
phenomena with many factors interacting with each other. Thus, limnological understanding is a prerequisite to identifying
sound solutions and to making wise judgments about reservoir management and restoration. Cooperation with other related disciplines
is necessary to establish the proper management plans and applications. Also, international cooperation is suggested to solve
environmental problems in agricultural reservoirs, particularly among the countries with similar agricultural practices, climate,
geology, and water uses.
Electronic Publication 相似文献
108.
Kyung?Min?Yoo Seok?Won?Lee Jae?Ryoun?YounEmail author Do?Heum?Yoon Young?Eun?Cho Jae-Pil?Yu Hyung?Sang?Park 《Fibers and Polymers》2003,4(2):89-96
A vertebral cage is a hollow medical device which is used in spine surgery. By implanting the cage into the spine column,
it is possible to restore disc and relieve pressure on the nerve roots. Most cages have been made of titanium alloys but they
detract the biocompatibility. Currently PEEK (polyether ether ketone) is applied to various implants because it has good properties
like heat resistance, chemical resistance, strength, and especially biocompatibility. A new shape of vertebral cage is designed
and injection molding of PEEK is considered for production. Before injection molding of the cage, it is needed to evaluate
process conditions and properties of the final product. Variables affecting the shrinkage of the cage are considered, e.g.,
injection time, packing pressure, mold temperature, and melt temperature. By using the numerical simulation program, MOLDFLOW,
several cases are studied. Data files obtained by MOLDFLOW analysis are used for stress analysis with ABAQUS, and shrinkage
and residual stress fields are predicted. With these results, optimum process conditions are determined. 相似文献
109.
Jae?Whan?ChoEmail author Sun?Hwa?Lee Jung?Hyun?So Jae?Yun?Jaung Kee?Jong?Yoon 《Fibers and Polymers》2004,5(3):239-244
Solution-cast films of polymethylmethacrylate (PMMA) and polyurethane (PU) containing polymeric styryl dye up to 5% by weight
were prepared to investigate their acid-sensitivity and mechanical and thermal properties. Original red samples due to styryl
dye turned out yellow very rapidly as they were exposed to acid vapor of hydrochloric acid or p-toluenesulfonic acid. According
to UV/VIS spectroscopic measurements, characteristic peak intensities near 430 nm and 520 nm increased or decreased relatively
with exposed amounts of acid, respectively. Both PMMA and PU samples showed uniform color distribution due to a good miscibility
between polymer and dye which can be evidenced by measurements of glass transition temperature. No significant difference
in acid-sensitivity was found between PU and PMMA except relative absorbance. However, dependence of their mechanical properties
on dye content was somewhat different with PU or PMMA. In case of PMMA, modulus and breaking stress increased up to about
50% with increasing dye content, whereas those of PU samples showed only slight increase. It was ascribed to whether the matrix
polymer was in the glassy or rubbery state. 相似文献
110.
Hur J Choi YY Park JH Jeon BW Lee HS Kim AR Lee JH 《Canadian journal of veterinary research》2011,75(1):49-56
Salmonella enterica subsp. enterica serovar Typhimurium was isolated from diarrheic piglets in 2 periods, 2000-2001 (n = 25) and 2005-2006 (n = 17). To compare the characteristics of the isolates collected during the 2 periods, all isolates were tested for antimicrobial resistance, the presence of virulence genes, and pulsed-field gel electrophoresis (PFGE) patterns. All 42 isolates were resistant to at least 1 of the 20 antimicrobials tested, and 39 (93%) were resistant to 2 or more antimicrobials. One isolate was resistant to 12 antimicrobials. Profiles of antimicrobial resistance revealed 20 resistance types. Several isolates were also resistant to quinolones and expanded-spectrum cephalosporins. Ten isolates (24%) were resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline (ACSSuT); only one isolate had been isolated in 2000-2001, indicating that this type of resistance has rapidly disseminated. Polymerase chain reaction (PCR) assays revealed that all the isolates carried invA. Among the 25 strains isolated in 2000-2001, all carried the sipA, sopA, sopD, sopE2, and ssaR genes, and 96% carried sopB and sifA. Among the 17 strains isolated in 2005-2006, all carried sifA, and approximately 90% carried sipA, sopA, sopB, sopD, sopE2, and ssaR. However, only 6 (14%) of the 42 isolates carried spvC. By PFGE analysis, all 42 strains were classified into 4 major clusters, basically by collection period. The genetic similarity according to PFGE suggests that the strains isolated from diarrheic piglets of this region within the same period may be closely related. 相似文献