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131.
Beraprost sodium (BPS) is an orally active prostacyclin analogue. The effects of BPS on the heart, including coronary circulation improvement, myocardial and vascular protection and anti-fibrosis effect on myocardium interstitium, have previously been demonstrated. However, the effects of BPS on hemodynamics, cardiac function and myocardial contractility in patients in the hypertrophic phase have not been clarified. Therefore, in the present study, the effects of BPS under long-term administration were investigated using the hypertension model of salt-sensitive Dahl rats. Six-week-old Dahl rats were divided into three groups, an 8% high salt diet group treated with BPS (BPS group), an untreated 8% high salt diet group (HHF group) and an untreated 0.3% low salt diet group (Control group), and observations were conducted until 17 weeks of age. In the BPS and HHF groups, the survival rates after 11 weeks of high salt diet intake were 87.5% and 47.1%, respectively (p<0.05). At 17 weeks of age, the atrial systolic peak velocity/early diastolic peak velocity and heart weight index of the BPS group decreased significantly compared with the HHF group (p<0.05). The HHF group exhibited significantly more severe myocardial fibrosis mainly in the endocardial layer of the left and right ventricles compared with the BPS and Control groups (p<0.05). In the present study, long-term BPS administration preserved diastolic function and prevented myocardial interstitial fibrosis in the non-compensatory phase. The results of the present study suggest that BPS is effective for treatment of hypertensive cardiac hypertrophy.  相似文献   
132.
A study was conducted to examine the long-term relationship among price of fish, harvest level, and resource condition using a bioeconomics model. Data on the annual amount of production and prices of octopus (Octopus vulgaris) in Morocco from 1970 to 2006 are plotted on a diagram to trace annual changes of price and production. The plotted pattern suggests a long-term movement of the yield-price equilibrium along the line of a theoretical long-term supply function curve of the bioeconomics model. The plotted data also suggests that there are four stages of resource exploitation for octopus in Morocco: (1) the underexploited stage from 1970 to 1987 which is characterized by small catch and low prices, (2) the maximum sustainable yield (MSY) stage from 1988 to 1998 which is characterized by moderate catch and intermediate prices, (3) the overexploited stage from 1999 to 2001 which is characterized by large catch and intermediate prices, and (4) the reduced stock stage after 2002 which is characterized by small catch and high prices. This result is consistent with the independent scientific research information on octopus harvested in Morocco. Our study indicates that an analysis of market information (i.e., amount of production and price) could be an effective tool in identifying approximate status of fishery resources.  相似文献   
133.
Tuna is one of the most important marine products in Japan, but fishery productivity is decreasing, especially for bluefin tuna (Thunnus orientalis, Thunnus thynnus) because of strict capture limits implemented by regional fisheries management organizations (RFMOs). Such capture limitations are necessitated by a shortage of resources. At the same time, full-cycle farming technology of Thunnus orientalis has recently been developed. This technology is set to achieve productivity levels at an industrial scale. In Japan, however, most consumers are believed to have a negative image of farmed products; therefore effective marketing is necessary. This study employs conjoint analysis via an internet questionnaire to clarify consumer preferences and the determine the possibility of marketing through provision of information to consumers regarding bluefin tuna and the environmental background of the problem. The results show that once consumers are provided with enough information about bluefin tuna, particularly in terms of the underlying resources problem, the willingness to pay (WTP) for full-cycle farmed fish is greater compared to conventionally farmed fish. Furthermore, if the product has an “eco-label,” the WTP increases drastically. Therefore, the informational process is important for marketing, and labeling can be an efficient marketing method.  相似文献   
134.
The efficiency of planting a hybrid larch F1 at two planting densities and of using seedlings of hybrid larch F1 or rooted cuttings of Gream, the registered variety, was investigated. Significantly more time was required to move from one planting spot to the next in plots with 625 seedlings/ha than in plots with 1,333 seedlings/ha, but there was no significant difference between seedlings and rooted cuttings. Approximately 18% more time was needed to plant a single planting stock at the low planting density than at the high density. The need to prune roots or enlarge a planting hole occurred more often for rooted cuttings than for seedlings, and 17% more time was needed to plant rooted cuttings of Gream than seedlings.  相似文献   
135.
ABSTRACT:   The Bioplorer (BP) (Matsushita Ecology Systems Co. Ltd, Kasugai, Aichi-ken, Japan) is an apparatus that consists of a light-emitting diode and optical and image analysis systems. This instrument has been developed and used for the semi-automatic counting of total microbes, mainly in food, cosmetics and industrial products. In this study, the applicability of BP to the detection and enumeration of eukaryotic and prokaryotic cells, after the fluorescent in situ hybridization (FISH) procedure, was examined. The cells of a yeast ( Candida albicans ) and a bacterium ( Escherichia coli ) were specifically labeled using an oligonucleotide probe with fluorochrome and then counterstained with 4', 6-diamidino-2-phenylindole (DAPI). The numbers of cells after FISH treatment and DAPI staining agreed well, indicating that the BP optical device and image analysis system had enough sensitivity to detect and quantify eukaryotic and prokaryotic cells. Because of its simplicity and reliability, BP can be a new tool for quantification of specifically labeled target microorganisms, both in industrial products and natural samples.  相似文献   
136.
ABSTRACT:   Mid-water trawl surveys were conducted from late August to late September in 1999 and 2004 in order to investigate the distribution pattern, hatch date, and growth of juvenile Pacific bluefin tuna Thunnus orientalis in the Sea of Japan. Juveniles were collected at the stations where ambient water temperature (mean water temperature from surface to 30 m deep, WT0−30) was 23.4–25.9°C, and most of them were found in waters where WT0−30 was higher than 24°C. Sampled juveniles ranged 108–280 mm fork length. Based on otolith analysis, they were estimated to grow to approximately 180 and 250 mm at 60 and 90 days old, respectively, and showed similar growth to that of Atlantic bluefin tuna in the Mediterranean Sea. The back-calculated hatch date of the samples was mostly in July and most juveniles spawned in the Sea of Japan.  相似文献   
137.
Mechanism of reduction of exchangeable aluminum in acid Andosols treated with gypsum was studied by using cation exchange resin methods to determine the amount of polymerized aluminum. Two types of acid Andosols were used as test soils: Kitakami light colored Andosol (fine, mixed, mesic, Andic Dystrochrept) and Kawatabi thick high humic Andosol (medial, mesic mixed Alic Pachic Melanudand). Polymerization of aluminum in the soil solution of both Kitakami and Kawatabi Andosols treated with gypsum was suggested based on an analysis using cation exchange resin methods, whereas that in monomer aluminum solution was not detected. Accumulation of polymerized aluminum in both Kitakami and Kawatabi Andosols was determined by using cation exchange resin, and the amounts of polymer aluminum trapped by the resin and the ratio of polymer aluminum to monomer aluminum were increased with the incubation time. The values of CEC which decreased in the Kitakami Andosol after gypsum treatment were almost equivalent to the amounts of cation exchange sites occupied by polymer aluminum ions which were calculated based on the decrease of the values of Y l. We conclude that the mechanism of reduction of exchangeable aluminum in strongly acid Andosols treated with gypsum is as follows: firstly, exchangeable aluminum adsorbed on the cation exchange sites of soils may be released into the soil solution due to the increase in the ion strength caused by gypsum application, and then monomer aluminum in soil solution may be polymerized in the presence of soil colloidal materials. Consequently, the polymer aluminum formed in the soil solution may be selectively and irreversibly fixed on the cation exchange sites of 2 : 1 clay minerals.  相似文献   
138.

Background  

Heavy metals, especially copper, nickel, lead and zinc, have adverse effects on terrestrial and in aquatic environments. However, their impact can vary depending on the nature of organisms. Taking into account the ability of heavy metals to accumulate in sediments, extended knowledge of their effects on aquatic biota is needed. In this context the use of model organisms (often unicellular), which allows for rapid assessment of pollutants in freshwater, can be of advantage. Pentachlorophenol has been extensively used for decades as a bleaching agent by pulp- and paper industry. Pentachlorophenol tends to accumulate in the nature. We aim to determine if photosynthesis and motility can be used as sensitive physiological parameters in toxicological studies of Chlamydomonas reinhardtii, a motile green unicellular alga. It is discussed if photosynthesis and motility can be used as sensitive physiological parameters in toxicological studies.  相似文献   
139.
Pre-harvest sprouting (PHS) is one of the serious problems for wheat production, especially in rainy regions. Although seed dormancy is the most critical trait for PHS resistance, the control of heading time should also be considered to prevent seed maturation during unfavorable conditions. In addition, awning is known to enhance water absorption by the spike, causing PHS. In this study, we conducted QTL analysis for three PHS resistant related traits, seed dormancy, heading time and awn length, by using recombinant inbred lines from ‘Zenkouji-komugi’ (high PHS resistance) × ‘Chinese Spring’ (weak PHS resistance). QTLs for seed dormancy were detected on chromosomes 1B (QDor-1B) and 4A (QDor-4A), in addition to a QTL on chromosome 3A, which was recently cloned as TaMFT-3A. In addition, the accumulation of the QTLs and their epistatic interactions contributed significantly to a higher level of dormancy. QDor-4A is co-located with the Hooded locus for awn development. Furthermore, an effective QTL, which confers early heading by the Zenkouji-komugi allele, was detected on the short arm of chromosome 7B, where the Vrn-B3 locus is located. Understanding the genetic architecture of traits associated with PHS resistance will facilitate the marker assisted selection to breed new varieties with higher PHS resistance.  相似文献   
140.
In this study, a weeding-duration model for Larix kaempferi plantations was developed that employs a generalized linear model. The number of years that weeding is necessary is the response variable, and elevation, slope, maximum snow depth, annual precipitation, geological type, soil type, site index, slope aspect, and vegetation type are explanatory variables. Among the explanatory variables, geological type, soil type, slope aspect, and vegetation type are categorical data. We assumed a Poisson distribution for the response variable. The link function was log. Among the models that could be developed from these variables, we chose the model with the smallest Akaike’s information criterion (AIC). The weeding-duration model can be written as follows: years that weeding is necessary = Exp (−0.0172833 × site index + 0.0014053 × maximum snow depth (cm) + 1.7417731). The results of this study imply that weeding of Larix kaempferi plantations is needed for more years as the maximum snow depth increases and fewer years as the site index increases. This model is useful for cost–benefit analyses of afforestation or reforestation with Larix kaempferi.  相似文献   
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