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921.
922.
A total of forty-eight finishing pigs were used to determine the effects of humic substances (HS) on growth performance, blood characteristics, and meat quality. The finishing pigs were assigned randomly by weight to three treatments. The dietary treatments included: 1) Control (CON; basal diet), 2) HS1 (basal diet + 5% humic substances) and 3) HS2 (basal diet + 10% humic substances). Results of the whole experimental period showed that addition of 10% HS to the diet, significantly increased average daily gain (ADG) and gain/feed (G:F) (P < 0.05). At the end of the experiment, the relative lymphocyte counts (% of total white blood cells) of pigs fed HS2 diet were higher (P < 0.05) than that of pigs fed CON diet. The Minolta color parameter a of pigs fed HS2 was similar to that of pigs fed HS1, however, it was higher (P < 0.05) than that of pigs fed CON diet. The inclusion of either 5% or 10% HS significantly decreased backfat thickness (P < 0.05). The marbling score was increased significantly (P < 0.05) when diets were supplemented with HS at a level of 10%. The results of this study suggest that HS might be utilized as a feed additive in the diet. It could improve growth performance, relative lymphocyte counts and meat quality. 相似文献
923.
Sungyoung Han Haengbok Cheon Hangmyo Cho Juhyung Kim Ji-Houn Kang Mhan-Pyo Yang Youngwon Lee Heechun Lee Dongwoo Chang 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(4):395-400
Computed tomographic arthrography (CTA) of four cadaveric canine stifles was performed before and after partial cranial cruciate ligament rupture in order to verify the usefulness of CTA examination for the diagnosis of partial cranial cruciate ligament rupture. To obtain the sequential true transverse image of a cranial cruciate ligament, the computed tomography gantry was angled such that the scanning plane was parallel to the fibula. True transverse images of cranial cruciate ligaments were identified on every sequential image, beginning just proximal to the origin of the cranial cruciate ligament distal to the tibial attachment, after the administration of iodinated contrast medium. A significant decrease in the area of the cranial cruciate ligament was identified on CTA imaging after partial surgical rupture of the cranial cruciate ligament. This finding implies that CTA can be used for assessing partial cranial cruciate ligament ruptures in dogs. 相似文献
924.
Cho Jae-Young Han Kang-Wan Choi Jin-Kyu Kim Young-Joo Yoon Kwang-Sik 《Soil Science and Plant Nutrition》2013,59(3):301-306
Abstract The study was carried out to investigate the water balance and runoff and infiltration losses of nutrients in a paddy field plot located in southern Korea. Field monitoring was carried out during the cropping season from May 1, 1999 to September 30, 2000. The soil of the experimental paddy field belonged to the Jisan series (SiL; fine loam, mixed, mesic Fluventic Haplaquepts) covering on area of 5,000 m2 (100 m × 50 m). The measured input quantities of N and P into the paddy field were as follows: 122 and 140 kg N ha?1 and 29 and 30 kg P2O5 kg ha?1 from chemical fertilizer, 20 and 28 kg N ha?1 and 0.35 and 0.36 kg P ha?1 from precipitation, and 26 and 35 kg N ha?1 and 0.57 and 0.72 kg P ha?1 from irrigation water, respectively. The measured outputs of N and P during the study period were as follows: 48 and 52 kg N ha?1 and 1.1 and 1.6 kg P ha?1 from runoff water, and 9 and 12 kg N ha?1 and 0.04 and 0.05 kg P ha?1 from infiltration. The runoff loading was the highest in June, presumably because of the higher concentrations of chemical components associated with chemical fertilizer application. The runoff losses of nutrients were compared to the amounts of nutrients supplied by chemical fertilizers. It was found that the losses of N accounted for 34.3 and 42.6% of the chemical fertilizer applied, while those of P accounted for 3.8 and 5.3%. The ratio between nutrient losses by infiltration and the chemical fertilizer applied was 6.4 and 9.8% for N and 0.1 and 0.2% for P, respectively. 相似文献
925.
Jae Sung Park Eunji Cho Ji-Yeon Hwang Sung Chul Park Beomkoo Chung Oh-Seok Kwon Chung J. Sim Dong-Chan Oh Ki-Bong Oh Jongheon Shin 《Marine drugs》2021,19(1)
Six new bis(indole) alkaloids (1–6) along with eight known ones of the topsentin class were isolated from a Spongosorites sp. sponge of Korea. Based on the results of combined spectroscopic analyses, the structures of spongosoritins A–D (1–4) were determined to possess a 2-methoxy-1-imidazole-5-one core connecting the indole moieties, and these were linked by a linear urea bridge for spongocarbamides A (5) and B (6). The absolute configurations of spongosoritins were assigned by electronic circular dichroism (ECD) computation. The new compounds exhibited moderate inhibition against transpeptidase sortase A and weak inhibition against human pathogenic bacteria and A549 and K562 cancer cell lines. 相似文献
926.
Byeoung-Kyu Choi Duk-Yeon Cho Dong-Kug Choi Phan Thi Hoai Trinh Hee Jae Shin 《Marine drugs》2021,19(2)
Two new phomaligols, deketo-phomaligol A (1) and phomaligol E (2), together with six known compounds (3–8) were isolated from the culture broth of the marine-derived fungus Aspergillus flocculosus. Compound 1 was first isolated as a phomaligol derivative possessing a five-membered ring. The structures and absolute configurations of the new phomaligols were determined by detailed analyses of mass spectrometry (MS), nuclear magnetic resonance (NMR) data, optical rotation values and electronic circular dichroism (ECD). In addition, the absolute configurations of the known compounds 3 and 4 were confirmed by chemical oxidation and comparison of optical rotation values. Isolated compounds at a concentration of 100 μM were screened for inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 microglial cells. Among the compounds, 4 showed moderate anti-neuroinflammatory effects with an IC50 value of 56.6 μM by suppressing the production of pro-inflammatory mediators in activated microglial cells without cytotoxicity. 相似文献
927.
Mari Yotsu-Yamashita Sawako Kondo Shinya Segawa Yi-Chin Lin Haruhiko Toyohara Hisatomi Ito Keiichi Konoki Yuko Cho Takafumi Uchida 《Marine drugs》2013,11(1):165-183
Two novel phlorotannins with a molecular weight of 974, temporarily named 974-A and 974-B, were isolated from the polyphenol powder prepared from the edible marine brown alga Ecklonia kurome Okamura, and their chemical structures were determined by spectroscopic method. The isolated yield of the total of 974-A and 974-B was approximately 4% (w/w) from the polyphenol powder. In 974-A, the carbon at the C2′ position in the A ring of phlorofucofuroeckol-A forms a C–C bond with the carbon at the C2″ position of the C ring of triphloretol-B, while in 974-B, phlorofucofuroeckol-B and triphloretol-B form a C–C bond in the same manner as in 974-A. These structures were supported by high resolution-MS/MS data. To evaluate the antioxidant activities, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and intracellular radical scavenging assay, using 2′,7′-dichlorofluorescin diacetate (DCFH-DA), were performed for 974-A, 974-B, and four known phlorotannins. The results of the DPPH assay showed that the IC50 values of 974-A, 974-B, phlorofucofuroeckol-A, and dieckol were significantly smaller than those of phlorofucofuroeckol-B, phloroglucinol, α-tocopherol, and ascorbic acid. Furthermore, the DCFH-DA assay suggested that 974-A, 974-B, and dieckol reduce intracellular reactive oxygen species most strongly among the tested compounds. 相似文献
928.
Sung Jin Kim Lim Jeong Seung Jin Lee Donghwan Cho Won Ho Park 《Fibers and Polymers》2013,14(9):1491-1496
In this study, biodegradable poly(D,L-lactic-co-glycolic acid) (PLGA) fibers were prepared by a melt-electrospinning and treated with plasma in the presence of either oxygen or ammonia gas to modify the surface of the fibers. The effects of processing parameters on the melt-electrospinning of PLGA were examined in terms of fiber morphology and diameter. Among the processing parameters, the spinning temperature and mass flow rate had a significant effect on the average fiber diameter and its distribution. The water contact angle of melt-electrospun PLGA fibers decreased significantly from 123 ° to 55 ° (oxygen plasma treatment) or to 0 ° (ammonia plasma treatment) by plasma treatment for 180 sec, while their water content increased significantly from 2.4 % to 123 % (oxygen plasma treatment) or to 189 % (ammonia plasma treatment). Ammonia gas-plasma enhanced the surface hydrophilicity of PLGA fibers more effectively compared to oxygen gas-plasma. X-ray photoelectron spectroscopy analysis supported that the number of polar groups, such as hydroxyl and amino groups, on the surface of PLGA fibers increased after plasma treatment. Overall, the microfibrous PLGA scaffolds with appropriate surface hydrophilicity and fiber diameter could be fabricated by melt electrospinning and subsequent plasma treatment, without a significant deterioration of fiber structure and dimensional stability. This approach of controlling the surface properties and structures of fibers could be useful in the design and tailoring of novel scaffolds for tissue engineering. 相似文献
929.
Exfoliated graphite nanoplatelets (EGN) were successfully coated with a liquid rubber amine-terminated poly(butadiene-co-acrylonitrile) (ATBN) at various concentrations. The rubber-coated EGN was incorporated into epoxy resin at different contents. The result revealed that the impact toughness of EGN/epoxy composite was increased by about 18 % with increasing the ATBN coating concentration. The impact strength, the flexural and dynamic mechanical properties, and the thermo-dimensional stability of EGN/epoxy composites were simultaneously enhanced by the incorporation of 1 wt% EGN coated with 10 wt% ATBN rubber into epoxy, which turns out a very small amount of 0.1 wt% ATBN compared to the epoxy resin. 相似文献
930.
Seung-Taek Oh Sung-Hoon Kim Heon-Young Jeong Jung-Min Lee Jae Whan Cho Jong-Shin Park 《Fibers and Polymers》2013,14(2):173-181
The purpose of this study is to fabricate a smart wound dressing by hybridizing hydrophilic polyurethane foam (PUF) and alginate hydrogel. Hydrophilic PUF is used to maintain damaged tissue in a moist environment. Despite its many strong points as a wound dressing, hydrophilic PUF cannot be loaded with ingredients such as growth factors and cytokines that would enhance wound healing. Therefore, we introduce a pH-sensitive alginate hydrogel with the ability to selectively release drugs within the pH range of wounded skin. Due to the small pore size of PUF and the high viscosity of the alginate solution, the two are not easily penetrable. As such, a vacuum method is used to insert alginate hydrogel into the PUF. The optimum conditions for the vacuum method chosen are to be proposed. However, the mechanical strength of PUF decreased after containing alginate hydrogel. Therefore, Na-alginate powder for PUF, various types of crosslinking agents and jute fiber for alginate hydrogel were introduced to improve the mechanical properties of hydrogel/PUF hybrid wound dressing. Three different types of crosslinking agents are used for the gel formation. The most suitable crosslinking agent and its concentration for alginate hydrogel is also determined by the experiments. The experimental results are discussed with proper schemes and reasonable explanations. 相似文献