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181.
An improved method was investigated for sodium dodecyl sulfate polyacrylamide slab gel electrophoresis (SDS-PAGE) to facilitate the analysis of the giant myofibrillar proteins, connectin and nebulin, in fish meat by using jack mackerel (Trachurus japonicus) as the sample fish. It was established that separation of the alpha-connectin band from the beta-connectin band by SDS-PAGE could be achieved by using 3-5% gradient gels with glycerol to facilitate the formation of a gradient with polymerization at 35 degrees C. SDS-PAGE samples of white dorsal muscle from the jack mackerel were homogenized with a 2% SDS solution containing an inhibitor mixture (1 microg/mL of phenylmethanesulfonyl fluoride, 1 microg/mL of leupeptin, and 1 microg/mL of E-64) and heated at 50 degrees C for 20 min. Heating these samples at 100 degrees C for 2 min resulted in the disintegration of connectin but did not affect nebulin. A purified myofibril sample and a whole muscle sample showed similar changes in the overall rate of degradation of whole connectin and nebulin during the postmortem storage period, but it was clear that beta-connectin was cleaved from alpha-connectin during the preparation of myofibrils at the early stage postmortem. Storage of the SDS-PAGE samples at -85 degrees C was preferable to storage at -18 degrees C for a long period.  相似文献   
182.
It is widely recognized that saturated hydraulic conductivity is dominated by the micromorphology of soil pores rather than by the merely total porosity or dry bulk density. Nevertheless, some researchers are reporting that the decrease in saturated hydraulic conductivity of subsoil is simply associated with the decrease in soil porosity or increase in dry bulk density. Based on these understandings in published papers and on our preliminary field investigation, we assumed that micromorphology of soil pores in topsoils is subjected to be destroyed with continuous disturbance by frequent tillage while subsoils tend to be compacted without serious changes of micromorphology of soil pores. Thus, we focused on finding the dependence of saturated hydraulic conductivity on dry bulk density by separating the soils into tilled layer and compacted layer. The objective of this study was to describe the relationship between saturated hydraulic conductivity and dry bulk density using a theoretical model, the non-similar media concept (NSMC) model, capable of predicting saturated hydraulic conductivities of soils with different values of dry bulk densities. The study area was located near the Tone River in Saitama Prefecture, Japan, where the soils were classified into Haplic Brown Lowland Soils according to the Classification of Cultivated Soils in Japan (Eutric Fluvisol according to FAO/UNESCO). Two sites, where the topsoils were seasonally tilled while the subsoils were sustained as it is, and another site where the topsoil was seasonally tilled, too, but extra deep tillage (1 m tillage depth) had been done, were chosen for the measurements. The saturated hydraulic conductivities and dry bulk densities of undisturbed soil cores from different depths were measured in the laboratory. The NSMC model was carefully applied only when the soil textures were the same among samples. The well-known conventional equations formulated by Kozeny–Carman and by Campbell, were used to compare the applicabilities with the NSMC model. The NSMC model succeeded in predicting the saturated hydraulic conductivities in the compacted subsoils. On the other hand, the NSMC model was not applicable to the tilled topsoils and to the deeply tilled subsoil. The saturated hydraulic conductivity of tilled topsoils and deeply tilled subsoil was always lower than that of compacted subsoils at the same dry bulk densities. The Kozeny–Carman and Campbell equations both failed in the prediction of saturated hydraulic conductivity in subsoil. It was concluded that the saturated hydraulic conductivity of subsoils under compaction without extreme disturbance is well related with its dry bulk density by the NSMC model.  相似文献   
183.
The residual amount of nonionized pesticides incorporated to foliage and stem (foliage) and seed (fruit) of crops via root hairs from the water phase was estimated using the uptake models newly including metabolic parameters by which the amount of intact pesticide remaining in crops was considered with its proportion in a transpiration stream. A new parameter was also introduced for the seed model that accounts for the pesticide loss by adsorption to the inner surface of xylem tissue. Validation of the model was conducted using six pesticides with soybean and spinach plants. The ratio of the predicted concentration of pesticide to the measured one was 0.44-1.49 and 0.57-2.93 with foliage and seed models, respectively, showing that these improved models would be effective as a prediction tool.  相似文献   
184.
The positive features of Centropomids and Latids for cultivation are analysed and highlighted. The main life cycle characteristics as well as market prices and demands are presented. Good growth, highly efficient food conversion ratios and energy utilization allow very high biomass yields per unit volume in nursery and grow‐out systems. They have shown notable tolerances to main environmental conditions, as well as considerable versatility in adapting to culture systems (cages, ponds and tanks), and culture intensity (extensive, semi‐intensive, intensive and superintensive), especially in estuarine and coastal sites and ponds. These positive features provide them with a high culture potential. A general summary of their culture is presented, based on the commercial cultivation of the Asian sea bass or barramundi Lates calcarifer as well as the experimental and pilot‐scale results from the main American species. The importance of hatchery fry production as an essential culture pre‐requisite is emphasized, in addition to an analysis of the main difficulties and constraints for future development.  相似文献   
185.
Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single (17)O-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is (16)O-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion.  相似文献   
186.
Turmeric, the rhizome of Curcuma longa L., has a wide range of effects on human health. Turmeric oleoresin, an extract of turmeric, is often used for flavoring and coloring. Curcuminoids and turmeric essential oil are both contained in turmeric oleoresin, and both of these fractions have hypoglycemic effects. In the present study, we comprehensively assessed the effect of turmeric oleoresin on hepatic gene expression in obese diabetic KK-Ay mice using DNA microarray analysis and quantitative real-time polymerase chain reaction (PCR). Female KK-Ay mice aged 6 weeks (n = 6/group) were fed a high-fat diet containing turmeric oleoresin, curcuminoids, and essential oil for 5 weeks. The same diet without any of these fractions was used as a control diet. Ingestion of turmeric oleoresin and essential oil inhibited the development of increased blood glucose and abdominal fat mass, while curcuminoids only inhibited the increase in blood glucose. DNA microarray analysis indicated that turmeric oleoresin ingestion up-regulated the expression of genes related to glycolysis, beta-oxidation, and cholesterol metabolism in the liver of KK-Ay mice, while expression of gluconeogenesis-related genes was down-regulated. Real-time PCR analysis was conducted to assess the contribution of the curcuminoids and essential oil in turmeric oleoresin to the changes in expression of representative genes selected by DNA microarray analysis. This analysis suggested that curcuminoids regulated turmeric oleoresin ingestion-induced expression of glycolysis-related genes and also that curcuminoids and turmeric essential oil acted synergistically to regulate the peroxisomal beta-oxidation-related gene expression induced by turmeric oleoresin ingestion. These changes in gene expression were considered to be the mechanism by which the turmeric oleoresin affected the control of both blood glucose levels and abdominal adipose tissue masses. All of these results suggest that the use of whole turmeric oleoresin is more effective than the use of either curcuminoids or the essential oil alone.  相似文献   
187.
A three dimensional scaffold is essential in mesenchymal stem cells (MSCs) delivery in cell-based therapy for facilitating cell adherence, migration, proliferation, and differentiation. The objectives of this study were to evaluate the possibility of β-tricalcium phosphate incorporated gelatin sponges (Gelatin/β-TCP sponge) as scaffolds for equine MSCs and to examine the effects of seeding density and seeding method on the proliferation of equine MSCs in the Gelatin/β-TCP sponges. Mononuclear cells and MSCs isolated from bone marrow were seeded into Gelatin/β-TCP sponges at different densities by different seeding methods-static or agitated methods. Proliferation of the MSCs in Gelatin/β-TCP was assessed using the Cell Counting Kit-8 assay and histological examination. Distribution and proliferation of MSCs in the Gelatin/β-TCP sponge were observed, and the Gelatin/β-TCP sponge supported limited growth when seeded at high density. We also found that the agitated seeding method enhanced the proliferation of MSCs. This study demonstrated the suitability of Gelatin/β-TCP sponges for the proliferation and maintenance of equine MSCs. These results contribute to the application of MSC-seeded Gelatin/β-TCP sponges in equine medicine.  相似文献   
188.
To determine the lifespan of Siebold’s beech (Fagus crenata), a dominant canopy tree species of the cool temperate forests of Japan, we estimated the age of 33 mature beech trees felled by a large typhoon in September 2004 at Karibayama, in southern Hokkaido. The study site lies within one of the northernmost distributions of Siebold’s beech populations in Japan. We counted tree rings from tree disks at a height of 1 m, and diameter growth was measured in annual increments. The sample age revealed two major peaks at 240 and 175 years. The diameter growth was good between 40 and 60 years of age and gradually decreased after 70 years of age. Annual diameter increments were noticeably small in good fruiting years, indicating a large allocation of annual carbon gains to the reproductive organs. Bud scale counts of juvenile trees revealed that the age at which the height reached 1 m was approximately 6–13 years. The lifespan of Siebold’s beech in the Karibayama population was therefore estimated to be approximately 250 years, an estimation that is higher than that previously reported for this species in the northernmost populations.  相似文献   
189.
Blastocystis infection in amphibians was surveyed in three species of anuran and one species of urodele amphibians captured at two distinct locations in Japan. All three species of frogs were highly infected with Blastocystis, while 69 individual urodele newts, Cynopus pyrrhogaster, were negative for infection. Eleven Blastocystis isolates (47.8%) were recovered from 23 Rana nigromaculata leopard frogs. Twenty-three (92%) of 25 Rana catesbeiana bullfrogs and all (100%) of 24 Bufo japonicus japonicus toads were positive for Blastocystis. Two distinct populations of the toad and bullfrog showed a high prevalence (100 or 84.6%) of Blastocystis infection, while in two populations of the leopard frog only one population was positive for Blastocystis (84.6%). Three Blastocystis isolates from different species of the frogs were established. Since none of the three isolates could survive at 37 degrees C, a temperature tolerance assay was performed to assess the optimal growth temperature and to determine the range of non-lethal temperatures. During the exponential growth phase of 3- or 4-day cultures at 25 degrees C, three isolates were exposed to 4, 28, 31, or 34 degrees C for 3 days and then returned to 25 degrees C to monitor the cell growth. Based on the optimal growth temperatures and different ranges of temperature tolerance among the three new isolates from frogs and two known species, Blastocystis hominis and Blastocystis lapemi, it was established that the three isolates recovered from different species of frogs had different physiological features from B. hominis and B. lapemi.  相似文献   
190.
New perennial canker diseases of Abies veitchii and Acer crataegifolium are described. Pathogenicity of the causal fungus was confirmed on stems of young Abies and Acer trees using two monoascospore isolates from the perithecia from the two tree species. The causal fungus, producing Nectria-state-teleomorph and Cylindrocarpon-anamorph, was identified as Nectria castaneicola. It was then transferred to the genus Neonectria, as N. castaneicola (W. Yamam. et Oyasu) Tak. Kobay. et Hirooka, comb. nov. followed by the recent concept of Nectriaceae.  相似文献   
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