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91.
Computed tomography (CT) exams were conducted to determine the distribution of abdominal fat identified based on the CT number measured in Hounsfield Units (HU) and to measure the volume of the abdominal visceral and subcutaneous fat in minipigs. The relationship between the CT-based fat volumes of several vertebral levels and the entire abdomen and anthropometric data including the sagittal abdominal diameter and waist circumference were evaluated. Moreover, the total fat volumes at the T11, T13, L3, and L5 levels were compared with the total fat volume of the entire abdomen to define the landmark of abdominal fat distribution. Using a single-detector CT, six 6-month-old male minipigs were scanned under general anesthesia. Three radiologists then assessed the HU value of visceral and subcutaneous abdominal fat by drawing the region of interest manually at the T11, T13, L1, L3, and L5 levels. The CT number and abdominal fat determined in this way by the three radiologists was found to be correlated (intra-class coefficient = 0.9). The overall HU ranges for the visceral and subcutaneous fat depots were -147.47 to -83.46 and -131.62 to -90.97, respectively. The total fat volume of the entire abdomen was highly correlated with the volume of abdominal fat at the T13 level (r = 0.97, p < 0.0001). These findings demonstrate that the volume of abdominal adipose tissue measured at the T13 level using CT is a strong and reliable predictor of total abdominal adipose volume.  相似文献   
92.
We investigated the effect of probiotics from anaerobic microflora with prebiotics (synbiotics) on growth performance, noxious gas emission and fecal pathogenic bacteria populations in growing pigs. The basal diet, which contained approximately 25% corn, 24% whey, 12% wheat and 12% soybean meal, was supplemented alternatively with 0.15% antibiotics (US diet), prebiotics and 0.2% probiotics from anaerobic bacteria (BS diet), yeast (YS diet), mold (MS diet) or compounds (CS diet). One hundred and fifty pigs were fed an experimental diet for 15 days. Although the growth performance was not affected by supplemental synbiotics, the BS group showed higher dry matter and crude protein digestibility. The BS group decreased fecal ammonia and amine gas emissions, and increased fecal acetate gas emission compared with the US group. All synbiotics groups decreased in fecal propionate gas emission. Fecal Escherichia coli population was lower in the synbiotics groups than in the US group. Therefore, the results of the present study suggest that synbiotics exert similar effects with antibiotics on the nutrient digestibility and fecal microflora composition in growing pigs. Moreover, synbiotics can also decrease the fecal noxious gas emission in growing pigs.  相似文献   
93.
Molecular diversity of methanogens in the rumen of Korean black goats was investigated with 16S rRNA gene clone libraries using methanogen‐specific primers. The libraries were composed of rumen fluid‐associated methanogens (FAM) and rumen particle‐associated methanogens (PAM) from rumen‐fistulated Korean black goats. Among the 141 clones of the FAM library, the sequences were mostly related to two phyla, the Methanobacteriaceae family (77.3%) and the Thermoplasmatales family (22.7%); and among the 68 clones of the PAM library, sequences were also mainly clustered in the two phyla, the Thermoplasmatales family (63.24%) and the Methanobacteriaceae family (35.29%). Most of the sequenced clones in the two libraries were closely related to uncultured methanogenic archaeon. Quantitative real‐time PCR revealed that PAM (8.97 log 10) had significantly higher (P < 0.01) density of methanogens by the methanogenic 16S rRNA gene copies than FAM (7.57 log 10). The two clone libraries also showed difference in Shannon index (FAM library 1.70 and PAM library 1.59) and Chao 1 estimator (FAM library 18 and PAM library 17 operational taxonomic units). Apparent differences found in the microbial community from the two 16S rRNA gene libraries could be a result of such factors as the chemical and physical nature of the target material surface, types or component of diets, the interaction between the methanogens and other microbes, and age of the experimental goats.  相似文献   
94.
A metabolomics based approach has been used to study the infection of the Hwacheong rice cultivar (Oryza sativa L. cv. Hwacheong) with compatible (KJ201) and incompatible (KJ401) strains of the rice blast fungal pathogen Magnaporthe grisea. The metabolic response of the rice plants to each strain was assessed 0, 6, 12, 24, 36, and 48 h post inoculation. Nuclear Magnetic Resonance (NMR) spectroscopy and Gas and Liquid Chromatography Tandem Mass spectrometry (GC/LC-MS/MS) were used to study both aqueous and organic phase metabolites, collectively resulting in the identification of 93 compounds. Clear metabolic profiles were observed at each time point but there were no significant differences in the metabolic response elicited by each pathogen strain until 24 h post inoculation. The largest change was found to be in alanine, which was ~30% (±9%) higher in the leaves from the compatible, compared to the resistant, plants. Together with several other metabolites (malate, glutamine, proline, cinnamate and an unknown sugar) alanine exhibited a good correlation between time of fungal penetration into the leaf and the divergence of metabolite profiles in each interaction. The results indicate both that a wide range of metabolites can be identified in rice leaves and that metabolomics has potential for the study of biochemical changes in plant-pathogen interactions.  相似文献   
95.
Two newly emerged begomoviruses were isolated from naturally infected tomato (Solanum lycopersicum) plants grown in greenhouses at Jeju Island and Dangjin in Korea and their genomes were characterized. These viruses-infected plants had very small leaves that curled upward, yellow margins and a leathery appearance, and a bushy and stunted appearance with short internodes. Nucleotide (nt) sequence analysis of their genomes showed that they have a DNA-A component of a monopartite begomovirus. Their genomes comprised 2763 and 2764 nucleotides with six open reading frames. The results of nt sequence similarity analysis of DNA-A genome between the two Korean isolates and isolates of Tobacco leaf curl Japan virus (TbLCJV), Honeysuckle yellow vein virus (HYVV), Honeysuckle yellow vein mosaic virus (HYVMV), and Eupatorium yellow vein virus in Japan (EpYVV) showed that they are likely similar to HYVV-[Masuda] (89.4–92.8% nt identity). Consequently, we tentatively propose the two isolates’ names as HYVV-Jeju and -DJ according to the ICTV geminivirus rules. Phylogenetic relationship analysis of 33 DNA-A genome sequences using PAUP* 4.0b10 and MrBayes revealed that HYVV-Jeju and -DJ belong to the Far East Asian begomovirus species complex. Within the Far East Asian begomovirus species complex, HYVV-Jeju and -DJ are distantly related to EpYVV, HYVMV, and TbLCJV groups. Based on the presence of a recombination fragment spanning the C3 ORF, a recombinant origin was suggested for both HYVV-Jeju and –DJ, with parents close to Japanese isolates HYVMV-[SP1:00] and Eupatorium yellow vein virus (EpYVV)-[Suya]. In addition, the presence of a further recombination fragment spanning the IR suggested the parents of HYVV-DJ were close to HYVV-Jeju and EpYVV-[Suya].  相似文献   
96.
The effects of hydrogen temperature and agitation rate on the formation of total conjugated linoleic acids (CLA) and CLA isomers were studied during hydrogenation with a selective Ni catalyst. The CLA isomers were identified by using a 100-m cyano-capillary column gas chromatograph and a silver ion-impregnated HPLC. Reaction temperature and agitation rate greatly affected the quantities of total CLA and individual CLA isomers, and the time to reach the maximum quantity of CLA in the partially hydrogenated soybean oil. As the hydrogenation temperature increased, the maximum quantity of CLA in soybean oil increased, but the time to reach the maximum CLA content decreased. By increasing the hydrogenation temperature from 170 to 210 degrees C, the quantity of CLA obtained was about 2.6 times higher. As the agitation rate decreased, the CLA formation in soybean oil increased, and the time to reach the maximum CLA content also increased. The maximum CLA contents in soybean oil obtained during hydrogenation at 210 degrees C with agitation rates of 300, 500, and 700 rpm were 162.82, 108.62, and 66.15 mg total CLA/g oil, respectively. The present data showed that it is possible to produce high-CLA-content soybean oil without major modification of fatty acid composition by short-time (10 min) selective hydrogenation under high temperature and low agitation rate conditions.  相似文献   
97.
Fast skeletal light meromyosins (LMMs) of white croaker and walleye pollack were prepared in our expression system using Escherichia coli and determined for their polymer-forming ability and thermodynamic properties by using sodium dodecyl sulfate polyacrylamide gel electrophoresis and differential scanning calorimetry (DSC), respectively. White croaker LMM formed dimer by heating at 80 degrees C and showed only a single peak at 32.1 degrees C of temperature transition in DSC. On the other hand, walleye pollack LMM hardly formed polymer and showed four peaks at 27.7, 30.5, 35.8, and 43.9 degrees C. When Cys525 of white croaker LMM was replaced by alanine, this point-mutated LMM showed no change in its DSC profile but formed no dimer upon heating, suggesting a possible role of Cys525 in dimer formation. On the other hand, walleye pollack LMM where Cys491 was substituted by alanine changed its DSC profile, showing four peaks at 27.9, 29.1, 38.4, and 43.9 degrees C. However, this point-mutated LMM formed no dimer upon heating as in the case of native LMM. These results suggest that cysteine residue(s) participates in thermal gel formation of LMM when it locates in a suitable position of the sequence.  相似文献   
98.
Lipoxygenase inhibitory activity of octyl gallate   总被引:2,自引:0,他引:2  
Octyl gallate inhibited soybean lipoxygenase-1 (EC 1.13.11.12, type I) with an IC(50) of 1.3 microM. The inhibition of the enzyme by octyl gallate is a slow and reversible reaction without residual activity. The inhibition kinetics analyzed by Lineweaver-Burk plots indicates that octyl gallate is a competitive inhibitor, and the inhibition constant, K(I), was obtained as 0.54 microM. One molecule of octyl gallate scavenged six molecules of 1,1-diphenyl-2-picrylhydrazyl and inhibited autoxidative lipid peroxidation. In addition, octyl gallate was effective in preventing lipid peroxidation.  相似文献   
99.
Growth of the cellulose-synthesizing bacterium Acetobacter xylinum ATCC 53524 in media supplemented with 5% (w/v) glucose and 0.2% (w/v) of a water-soluble, nearly linear xylan from tobacco stalks resulted in the synthesis of a highly crystalline composite having a xylose/glucose ratio ranging from 0.06 to 0.24. The digestion of one composite (88% cellulose/12% xylan) by mixed ruminal microflora displayed kinetics of gas production similar to those of an unassociated mixture of the two components added in a xylan/cellulose ratio similar to that of the composite. The data suggest that intimate association of xylan and cellulose, as is typically found in secondary plant cell walls, does not inhibit the rate of digestion of the component polysaccharides.  相似文献   
100.
The bioactivity of Israeli Jaffa blond (Shamouti) fresh orange and Israeli Jaffa red Star Ruby (Sunrise) grapefruit juices was investigated in vitro and in vivo. The contents of bioactive compounds of these juices were determined. The influence of bioactive compounds on plasma lipids and plasma antioxidant activity in rats fed cholesterol-containing and cholesterol-free diets was assessed. Significant differences in the contents of dietary fibers were not found. The contents of total polyphenols, flavonoids, and anthocyanins in fresh orange and grapefruit juices were 962.1 +/- 27.2 and 906.9 +/- 27.1; 50.1 +/- 3.3 and 44.8 +/- 3.2; and 69.9 +/- 5.6 and 68.7 +/- 5.5 microg/mL, respectively. The antioxidant potential measured by the scavenging activity against nitric oxide, the beta-carotene-linoleate model system (beta-carotene), and the 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis(3-ethyl-benzothiazoline-6-sulfonic acid) diamonium salt assays was higher in orange juice but not significantly. A high level of correlation between contents of total polyphenols and flavonoids and antioxidant potential values of both juices was found. Diets supplemented with orange and to a lesser degree with grapefruit juices improved plasma lipid metabolism only in rats fed added cholesterol. However, an increase in the plasma antioxidant activity was observed in both groups. In conclusion, fresh orange and grapefruit juices contain high quantities of bioactive compounds, which guarantee their high antioxidant potential, and the positive influence on plasma lipid metabolism and plasma antioxidant activity could make fresh orange and grapefruit juices a valuable supplement for disease-preventing diets.  相似文献   
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