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71.
中韩古典园林是传统文化的结晶,并且是东方园林的两枝奇葩。中国园林与韩国园林属于本源和分支的关系,韩国园林很多方面传承了中国园林的造园手法及艺术特征;然而不同的自然人文环境也使两种园林风格迥异,在园林中起着十分重要构景作用的置石也不例外。本文试从置石的形态与应用手法对中韩园林的不同作一些分析。  相似文献   
72.
Mistletoes are parasite plants growing on various tree species,taking nutrients from the host.Beneficial compounds of mistletoe were used in medicine and these mistletoes were commonly collected from oak species that were not well identified.We analyzed the nutritional value by measuring proximate and mineral components of Korean mistletoe(Viscum album var.coloratum)from various host trees.Carbohydrate was the most proximate component in both leaves and twigs followed crude protein,crude fiber,crude ash and crude fat.While the contents of the proximate components and minerals varied among hosts and between plant parts,leaves contained higher crude protein and ash,and more minerals except for magnesium than twigs,although no significant difference was found inmistletoe grown on Prunus mandshurica.There were significant differences of proximate and mineral contents depending on the host species.Mistletoe grown on Chaenomeles sinensis contained higher levels of carbohydrates,crude fat,crude ash,magnesium,calcium,sodium,iron,and zinc than mistletoe grown on other species.Mistletoe grown on P.mandshurica contained high mineral levels of potassium,copper and phosphorous.The nutritional value of mistletoes were greatly influenced by the host species but among the hosts,specific nutrients accumulated in leaves more than in twigs,and vice versa.Based on the analysis,Korean mistletoe contains relatively good quality of nutrients and has high potential for dietary supplements as well as for medicinal compounds.  相似文献   
73.
β-Glucosidase (β-1,4-D-glucoside glucohydrolase: EC.3.2.1.21) catalyzes the hydrolysis of β-glucosidic bonds between saccharides and aryl or alkyl groups. A gene encoding β-glucosidase from Bacillus licheniformis KCTC 1918, an anaerobic spore-forming soil bacterium, was cloned and characterized. The structural gene for the β-glucosidase consists of 1410 bp encoding 469 amino acid residues, and has a molecular weight of 53.4 kDa as estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis with 12% separating gel. The enzyme activity was determined against pNPG as a substrate. The enzyme was optimally active at pH 6.0 (citrate-phosphate buffer) and 47°C. β-Glucosidase retained 100% of its original activity for 24 h. The activity of the enzyme was stimulated by glycerol and urea and was decreased by Ca2+, Cu2+, Hg2+, Mg2+, and Mn2+. In particular, Cu2+ had the strongest negative effect on β-glucosidase activity. The purified β-glucosidase was active against pNPG and cellobiose. When the β-glucosidase was tested for cellulose hydrolysis, the supplement of β-glucosidase with cellulose increased the glucose yield from pine wood powder by 139.8%.  相似文献   
74.
Influenza A virus infections continue to pose a major threat to humans and several animal species. Neuraminidase (NA) is one of the most promising targets for the development of drugs against influenza viruses because of its critical role in the viral life cycle. During the course of a search for NA inhibitors from edible natural sources, we found that the ethyl acetate layer of ethanol extracts of Ecklonia cava showed extremely high NA-inhibitory activity (72.1% inhibition at 30 μg/mL). Bioactivity-guided fractionation of the ethyl acetate layer yielded five phlorotannins, identified as phloroglucinol (1), eckol (2), 7-phloroeckol (3), phlorofucofuroeckol (4), and dieckol (5). The inhibitory activities of these compounds (1-5) against NAs from group-1 (A/Bervig_Mission/1/18 [H1N1], A/PR/8/34 [H1N1]) and group-2 (A/Hong Kong/8/68 [H3N2], A/Chicken/Korea/MS96/96 [H9N2]) influenza A were evaluated to determine potencies and kinetic behavior. Analyses using various in vitro influenza A virus NA assays showed that all five phlorotannin derivatives were selective NA inhibitors. Of the phlorotannins, phlorofucofuroeckol (4) exhibited the most potent inhibitory activities toward group-1 NAs (IC?? values, 4.5 and 14.7 μM), whereas dieckol (5) potently inhibited group-2 NAs. Kinetic analyses indicated that compounds 1-5 were all noncompetitive. Notably, these noncompetitive inhibitors synergized with oseltamivir to enhance the NA-inhibitory effects of oseltamivir.  相似文献   
75.
Obesity is increasing in developing countries. Population studies show a relationship between affluence and obesity. Changing food intake patterns with affluence such as preference for foods with less astringent polyphenolic compounds and dietary fibers may increase risk of metabolic dysfunctions due to caloric imbalance. Animal models of obesity consistently show that grape seed procyanidins prevent increases in body and abdo- minal adipose weight gain, plasma cholesterol, liver weight gain and inflammation in animals on high fat diets. The mechanisms are not clear because the oral intake of procyanidins results in pleiotropic interactions with proteins in the mouth, stomach, small intestine, cecum and colon that affect the rate of digestion of bioavailability of macronutrients, sterols, and dietary fiber. Procyanidins also bind bile acids and reduce intestinal permeability to inflammatory bacterial cell wall fragment. Procyanidins are not degraded or metabolized until reaching the lower gut where they can be metabolized into phenolic acids by gut bacteria. While they are metabolized by gut bacteria, they also alter total numbers and distribution of phyla and species of gut bacteria. Gut bacteria are recognized as significant contributors to obesity and obesity related metabolic diseases. The review examines the different pleiotropic effects of grape seed procyanidins that have a significant effect on metabolic disease in animal models of obesity.  相似文献   
76.
Soil-borne cereal mosaic virus (SBCMV) causes a severe disease in susceptible cultivars of winter wheat. The virus is vectored by the soil-borne protist Polymyxa graminis. Experiments were conducted to investigate whether SBCMV RNA2 could persist in seed from SBCMV-infected susceptible cultivars of winter wheat. Over 7,000 seedlings were generated from seed collected from two cultivars of SBCMV-infected winter wheat. Seedlings were grown in a glasshouse compartment and batch tested for the presence of SBCMV using real-time RT-PCR. The majority of batches tested positive for SBCMV, indicating an RNA2 transmission rate of 1.8–9.4% in wheat. The presence of the virus was confirmed by amplifying and sequencing a larger (400 bp) fragment of viral RNA2 in a sub-set of the seedlings testing positive by real-time RT-PCR. Root extracts from this sub-set tested negative for P. graminis using real-time PCR. The implications for disease epidemiology of this virus are discussed. The authors are British Civil Servants and as such their work is subject to British Crown Copyright. This means the exclusive copyright for the article cannot be transferred.  相似文献   
77.
OBJECTIVE: Whereas there are numerous reports in the literature relating the impact of maternal nutritional status on subsequent birth outcome, much less is known about the long-term impact on infant growth after birth. Therefore, we conducted a prospective cohort study to investigate the association of maternal micronutrient status (vitamins A, C and E, folate) and oxidative stress status in pregnancy with infant growth during the first year of life. DESIGN: Prospective cohort study. SETTING: Outpatient clinic of obstetrics, Ewha Womans University Hospital, Seoul, South Korea.Subjects and methodsTwo groups were constructed for this study - the Ewha pregnancy cohort (n = 677) and the infant growth cohort comprising follow-up live newborns of all the recruited pregnant women (n = 317). Maternal serum vitamin and urinary oxidative stress levels were collected and infant weights and heights were measured at birth and at 6 and 12 months after birth. RESULTS: Division of the subjects into folate-deficient and normal groups revealed that infant weight and height at 0, 6 and 12 months were adversely affected by folate deficiency. High maternal vitamin C was associated with increased infant weight and height at birth and after birth.ConclusionOur findings indicate the importance of preventing folate deficiency and supplementing vitamin C during pregnancy.  相似文献   
78.
The effects of feeding glucose during the 5 days before parturition on litter performance and on glucose concentration in sows were studied. At day 100 of gestation, 130 multiparous sows were assigned to the treatments. Late gestating sows were fed 0 g, 150 g, 250 g, 350 g and 450 g of glucose a day, respectively. During lactation, all sows were given free access to the same lactation diet (without glucose). One day before parturition, blood samples were collected from 30 sows (6 sows per treatment) at 10 before and 20, 40, 60 and 80 min after the meal. The supply of additional dietary glucose increased piglet birth weight ( P  < 0.05). Feed intake in week 1 and week 1–4 of lactation was greatest in sows fed the 0% glucose diet, least by sows fed the 18% glucose diet, and intermediate by sows fed the 6, 10, 14% glucose diets ( P  < 0.05). Basal glucose concentration and time of maximum glucose concentration after glucose intake were not affected by dietary treatment in the last 5 days of gestation. The sows fed the 14 and 18% glucose diets had greater maximum increase in glucose concentration than sows fed diet without glucose ( P  < 0.05). In conclusion, feeding glucose to sows during 5 days before parturition increased birth weight of live-born piglet and decreased sows feed intake during lactation, but did not affect the performance of sows and piglets.  相似文献   
79.
One hundred pigs (BW = 50.7 ± 1.89 kg) were used to investigate the effects of fermented garlic powder (FGP) in growing‐finishing pigs. Pigs were allotted to one of five treatments, included: (i) NC (basal diet); (ii) PC (NC + 44 mg/kg of Tylosin); (iii) FGP1 (NC + 1 g/kg FGP); (iv) FGP2 (NC + 2 g/kg FGP); and (v) FGP4 (NC + 4 g/kg FGP). Supplemental FGP increased average daily gain (ADG) and gain/feed ratio compared with those fed NC diet throughout the experiment (P < 0.05, linearly). Dietary PC treatment increased the ADG and average daily feed intake during the first 6 weeks (P < 0.05). The inclusion of FGP2 and FGP4 treatments had higher apparent total tract digestibility of dry matter and nitrogen (P < 0.05) than those in the NC treatment. Dietary NC treatment exhibited lower (P < 0.05) lymphocyte count (6 and 12 weeks) and immunoglobulin G (12 weeks) than those in the other treatments. Marbling scores were higher (P < 0.05) in FGP treatment groups than the NC treatments. Pigs fed on FGP2 and FGP4 diets evidenced lower 2‐thiobarbituric acid reactive substances value (P < 0.05) than those in the NC and PC treatments. Collectively, our findings demonstrated that the administration of FGP at a level of 2 or 4 g/kg improved growth performance, nutrient digestibility and meat quality in growing‐finishing pigs.  相似文献   
80.
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