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71.
A cholesterol-free diet containing dried powder of Jew's mellow leaves, persimmon leaves or sweet potato leaves respectively at 5% level as dietary fiber was fed to male Sprague-Dawley rats for about one month. The experiment was conducted twice except for sweet potato leaves. In the groups fed the diet mixed with powders of any of the three different dried green leaves, the hepatic cholesterol concentration significantly decreased. Such lowering was not observed in serum cholesterol concentration compared with the control (cellulose) group. A significant increase in fecal weight was observed in all the groups fed the green leaf samples. All the dried green leaves increased fecal excretion of bile acids per gram or per day compared with the control group in both experiments, but only the dried Jew's mellow leaves showed an increased excretion of neutral sterols. These results suggest that lowering of hepatic cholesterol by powdered green leaves is not necessarily due to the same factor, but to the increased fecal excretion of bile acids due to inhibited enterohepatic circulation in animals given these samples.  相似文献   
72.
Summary The development of a microbial community on cellulose (cellophane film and filter paper) buried in waterlogged soil was observed under a microscope. Throughout the decomposition of the cellulose, the biomass, immobilized N, ATP and gas metabolism of the microbial community were examined. As cellulose decomposition progressed, a microbial succession was recognized. This succession was divided into two stages. In the first stage, a few types of cellulolytic microorganisms predominated on the cellulose. Vigorous decomposition of the cellulose was accompanied by a rapid increase in microbial biomass, and H2 was evolved from the microbial community on the cellulose. In the second stage, the rate of cellulose decomposition was slow. The cellulose remaining was thickly covered with various types of microoganisms. The H2 produced was consumed by the microorganisms closely adhering to the remaining cellulose. In addition, non-cellular organic N accumulated on the remaining cellulose. A large part of the microorganisms seemed to be dormant in this stage. The trends in this microbial succession were similar to those found in ecosystem successions.  相似文献   
73.
Mechanical property changes due to the moisture content (MC) and/or temperature changes were examined for 15 Indonesian wood species. A static bending test was carried out at 20°C, 65% relative humidity (air-dry), and water-saturated at 20°C (wet-20) and 80°C (wet-80). For individual test conditions, modulus of elasticity (MOE) and modulus of rupture (MOR) increased linearly with specific gravity regardless of wood species; however, maximum deflection did not correlate with specific gravity for any MC or temperature conditions. The relative values of MOE and MOR measured in wet-20 to air-dry conditions were variously affected from slightly to strongly depending on the wood species. However, the relative values always decreased markedly when saturated in water at 80°C, regardless of wood species. The relative MOE, MOR, and maximum deflection values due to the change in MC or MC and temperature combined were independent of specific gravity but may be dependent on wood type: softwood or hardwood.  相似文献   
74.
[目的]了解新疆库米什一处金矿土壤可培养细菌的多样性及建立菌种资源库.[方法]采集库米什金矿土壤样品,采用两种不同培养基(LB,TSB)分离纯化细菌,对其进行形态观察(菌落及细胞)、生理测定、16SrDNA测序和系统进化分析.[结果]从两种培养基上总共得到50株细菌,根据基于16S rDNA的系统进化分析表明,50株菌分别属于3个大类群:厚壁菌门(Firmicutes ),放线菌门(Actinobacteria),γ-变形菌纲(γ-Proteobaeteria),12个属,30个分类单元.其中芽抱杆菌属(Bacillus)为优势细菌种群,占已测种群的63.3;.菌株L10-5与Bacillus foraminis (AJ717382)有96.463;的相似率,可能为潜在新种.[结论]库米什金矿土壤可培养细菌具有较高的多样性,存在潜在新菌种资源,值得进一步研究.  相似文献   
75.
The prevalence of Dirofilaria immitis in free-ranging raccoon dogs (Nyctereutes procyonoides viverrinus) was examined in the southeast region of Kanagawa Prefecture, Japan, using a rapid immunomigration (RIM) test kit. Between April 2007 and March 2010, we examined 108 raccoon dogs rescued and housed by the Kanazawa Zoological Garden. D. immitis infection was found in 8 (7.4%) raccoon dogs. This is the first report to reveal the prevalence of D. immitis infection in living raccoon dogs. The prevalence of the infection was lower than previously reported values obtained on postmortem examination. One reason might be that the present study included young raccoon dogs infected with immature worms. Significant high-risk areas of D. immitis infection in the raccoon dogs were not observed.  相似文献   
76.
Artificial insemination with frozen cauda epididymal sperm was performed in cats. Sperm were transmigrated from the epididymides in 10 male cats. The mean sperm motility and viability were 67% and 82.5%, respectively, and 11.6 x 10(7) sperm were recovered. The mean sperm motility after thawing was 24.0%. Eleven female cats received unilateral intrauterine insemination of 5 x 10(7) sperm, and the conception rate was 27.3% (3/11). This was the first case of conception obtained with frozen epididymal sperm in cats.  相似文献   
77.
The mammalian forelimb is adapted to different functions including postural, locomotor, feeding, exploratory, grooming and defence. Comparative studies on morphology of the mammalian scapula have been performed in an attempt to establish the functional differences in the use of the forelimb. In this study, a total of 102 scapulae collected from 66 species of animals, representatives of all major taxa from rodents, sirenians, marsupials, pilosa, cetaceans, carnivores, ungulates, primates and apes, were analysed. Parameters measured included scapular length, width, position, thickness, area, angles and index. Structures included supraspinous and infraspinous fossae, scapular spine, glenoid cavity, acromium and coracoid processes. Images were taken using computed tomographic (CT) scanning technology (CT‐Aquarium, Toshiba and micro CT‐LaTheta, Hotachi, Japan), and measurement values were acquired and processed using Avizo computer software and CanvasTM 11 ACD systems. Statistical analysis was performed using Microsoft Excel 2013. Results obtained showed that there were differences in morphological characteristics of scapula between mammals with arboreal locomotion and living in forest and mountainous areas and those with leaping and terrestrial locomotion living in open habitat or savannah. Differences were seen in the ratio of maximum length and maximum width, the orientation of scapular spine and the horizontal length of acromion and coracoid processes. The cause for the statistical grouping of the animals and the way the scapular shape covaries with habitat and to the type of locomotion and speed are discussed in detail.  相似文献   
78.
Myrosinase is a cytosolic plant enzyme present in daikon ( Raphanus sativus, Japanese white radish) roots that hydrolyzes 4-methylthio-3-butenyl glucosinolate (MTBGLS) into the natural pungent agent 4-methylthio-3-butenyl isothiocyanate (MTBITC), which possesses antimicrobial, antimutagenic, and anticarcinogenic properties. The concentration of MTBGLS, myrosinase activity, and production of MTBITC in seven daikon varieties (one conventional and six heirlooms) were determined to rank the activity of the glucosinolate-myrosinase system and identify critical factors influencing the production of MTBITC. The six heirloom varieties produced 2.0-11.5 times higher levels of MTBITC as compared to the conventional variety, Aokubi, which is consumed by the present Japanese population. The myrosinase was located exclusively in the outer epidermal layer in Aokubi, and MTBGLS was widely distributed throughout the root tissue. Although the skin is a potentially rich source of myrosinase in Aokubi, the skin is usually peeled off in the current practice of preparing daikon for cooking. New practices are therefore proposed for the preparation of daikon tubers that eliminate the peeling of the skin to avoid removing the enzyme needed to convert MTBGLS to the health-beneficial MTBITC. It is also concluded that the consumption of heirloom daikon varieties in addition to changes in food preparation will optimize the health benefits of daikon.  相似文献   
79.
Although a number of metal speciation methods are nowadays available, most water quality regulations are based on total metal concentrations. One of the main reasons for the ignorance of speciation is the lack of methods with potentiality for monitoring. Conditions that have to be met by such speciation methods are: simple performance, robust and sufficiently accurate. In this study the potential for monitoring purposes of Diffusive Gradients in Thin films (DGT) is investigated as part of a European project for sensor development for routine prediction of metal biouptake in natural waters. Performance characteristics of DGT have been assessed in experiments under controlled laboratory conditions and during in situ application over 4–9 months under different hydrological conditions in the rivers Meuse and Rhine. Results have been worked out for Cu, Ni and Pb. The study shows that DGT has sufficient potential as a robust tool in routine monitoring to observe trends in water quality. However, it appears that during in situ application of DGT the measurement uncertainty of the results is much larger than under laboratory conditions. The increase in measurement uncertainties will partially be due to uncertainties in some as constant considered factors in the calculation of the DGT concentration. For Cu and Ni, the average values for the reproducibility in the rivers Meuse and Rhine appeared to be 28% and 17%, respectively, whereas under laboratory conditions the reproducibilities for both metals were better than 10%. In the speciation of Cu, Ni and Pb in the rivers Meuse and Rhine, the labile fraction, determined using DGT, decreased in the series Ni, Cu, Pb. The ratio of the non-labile and labile fractions of the metals appeared to decrease with increasing content of Dissolved Organic Carbon (DOC).  相似文献   
80.
Various extraction and drying conditions for the isolation of kafirin from dry-milled, whole grain sorghum have been investigated, with a view to optimizing extraction of the protein for commercial food coatings and packaging films. The addition of sodium hydroxide to an aqueous ethanol extractant increased the yield and solubility of kafirin. Subsequent heat drying at 40 degrees C was shown to cause the kafirin to aggregate as indicated by an increase in intermolecular beta-sheets. Extraction of the flour using ethanol (70%, w/w) with 0.5% (w/w) sodium metabisulfite and 0.35% (w/w) sodium hydroxide at 70 degrees C followed by freeze-drying of the protein was found to produce a yield of 54% kafirin with good film-forming properties. The kafirin films were assessed for their sensory properties, tensile strength, strain, and water vapor permeability. Fourier transform infrared spectroscopy was used to study the secondary structure of the extracted kafirins. The best films were made with kafirin containing a large proportion of nativelike alpha-helical structures with little intermolecular beta-sheet content as indicated by the Fourier transform infrared reflectance peak intensity ratios associated with these secondary structures. The principal factor affecting the secondary structure of the protein appeared to be the temperature at which the protein was dried. Heat drying resulted in a greater proportion of intermolecular beta-sheets. Any industrial-scale extraction must therefore minimize protein aggregation and maximize native alpha-helical structures to achieve optimal film quality.  相似文献   
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