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Hideomi?AmanoEmail author Makoto?Kakinuma Daniel?A?Coury Haruka?Ohno Takaaki?Hara 《Fisheries Science》2005,71(5):1160-1166
ABSTRACT: To assess the effect of a seaweed mixture on lipid levels in serum as well as platelet aggregation in rats, Eisenia bicyclis ('Arame'), Hizikia fusiformis ('Hijiki') and Undaria pinnatifida sporophylls ('Mekabu'), all brown seaweeds, and Porphyra yezoensis ('Susabinori'), a red seaweed, were powdered and mixed in a ratio of 45:30:20:5 (w/w). When rats were fed a cholesterol-rich diet containing this mixture of seaweeds (9–10% w/w) for 28 days, serum total cholesterol, LDL-cholesterol, free cholesterol, and triglyceride levels declined significantly to 49.7%, 48.1%, 49.0% and 74.8%, respectively, of those of the control. Serum HDL-cholesterol, however, was unchanged. Though activated partial thromboplatin time, prothrombin time, antithrombin III activity, and fibrinogen levels in plasma were unchanged, the maximal ADP- and collagen-induced platelet aggregation decreased significantly to 89.0% and 85.5% control levels, respectively. These results indicate that this mixture of E. bicyclis , H. fusiformis , U. pinnatifida sporophylls, and P. yezoensis , is useful for the prevention of hyperlipidemia and thrombosis in rats. 相似文献
23.
Using a salmon migration model based on the assumption that swimming orientation is temperature dependent, we investigated the determining factors of the migration of juvenile and immature chum salmon (Oncorhynchus keta) in the North Pacific. We compared the predictions of the model with catch data of immature and juvenile chum salmon collected by Japanese research vessels from 1972 to 1999. The salmon migration model reproduced the observed distributions of immature chum salmon and indicates that passive transport by wind‐driven and geostrophic currents plays an important role in the eastward migration of Asian salmon. These factors result in a non‐symmetric distribution of Asian and North American chum salmon in the open ocean. The directional swimming component contributes to the northward migration in summer. The model results indicate that during the first winter Asian chum salmon swim northward against the southward wind‐driven currents to stay in the western North Pacific. This suggests that Asian chum salmon require more energy to migrate than other stocks during the first winter of their ocean life. 相似文献
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To determine how stock abundance fluctuations of walleye pollock Theragra chalcogramma are related to variations in reproductive characteristics, the length at 50% maturity of the fish sampled off the Pacific
coast of northern Japan from 1990 to 1999 was examined. In both sexes, the fish density increased, and the body length of
age-3-5 fish decreased, but the condition factor and the age at 50% maturity showed no clear trend during this period. Male
length at 50% maturity decreased, while value for females showed no clear trend. In both sexes, significant negative correlations
were found between density index (combined age-3-5) and each body length at age-3-5. Significant positive correlations were
seen between each body length at age-3-5 and length at 50% maturity in males. Positive correlation between body length at
age-5 and length at 50% maturity was significant in females from 1990 to 1999, except for the samples in 1998. We suggest
that the fish density might affect the length at maturity in males and possibly also in females. 相似文献
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Wood ash is a residual material produced during biomass burning. In the northeastern United States up to 80 % of the ash is spread on agricultural lands as a liming amendment with the remainder being disposed of in landfills. As well as raising soil pH, wood ash also adds plant nutrients to soil. This study is an examination of the plant availability of the P in 8 different soils amended with one wood ash. Plant availability was assessed by measuring the biomass and P concentration of corn (Zea mays) L.) plants grown in the greenhouse for 28 d in soil amended with either CaCO3 (control), wood ash to supply 200 mg kg?1 total P, or monocalcium phosphate (MCP) to supply 200 mg kg?1 total P and CaCO3. Both corn growth and P uptake were highest in the MCP treatments, intermediate in the wood ash treatments, and lowest in the controls for all soil types. The soil property which seemed to have the greatest influence on P availability was pH buffer capacity. The soils with the greatest capacity to buffer OH additions also tended to exhibit the greatest absolute P uptake from wood ash-amended soils and the greatest P uptake relative to that from MCP-amended soils. The ability of soil test extractants to predict uptake of P in the three soil treatments was examined. A buffered ammonium acetate extradant overestimated P availability in the ash-amended soils relative to the MCP-amended soils. An unbuffered, acid, fluoride-containing extract provided a measure of P levels that was consistent with P uptake from all soil treatments. In this study the predictive relationship was as follows: P uptake = 0.017× (Bray P, mg kg?1) + 1.19; r = 0.81. 相似文献
28.
Cytokinin oxidase regulates rice grain production 总被引:25,自引:0,他引:25
Ashikari M Sakakibara H Lin S Yamamoto T Takashi T Nishimura A Angeles ER Qian Q Kitano H Matsuoka M 《Science (New York, N.Y.)》2005,309(5735):741-745
Most agriculturally important traits are regulated by genes known as quantitative trait loci (QTLs) derived from natural allelic variations. We here show that a QTL that increases grain productivity in rice, Gn1a, is a gene for cytokinin oxidase/dehydrogenase (OsCKX2), an enzyme that degrades the phytohormone cytokinin. Reduced expression of OsCKX2 causes cytokinin accumulation in inflorescence meristems and increases the number of reproductive organs, resulting in enhanced grain yield. QTL pyramiding to combine loci for grain number and plant height in the same genetic background generated lines exhibiting both beneficial traits. These results provide a strategy for tailormade crop improvement. 相似文献
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A Setoguchi M Okuda E Nishida M Yazawa T Ishizaka S H Hong M Hisasue R Nishimura N Sasaki Y Yoshikawa K Masuda K Ohno H Tsujimoto 《American journal of veterinary research》2001,62(7):1134-1141
OBJECTIVE: To evaluate results of centrosome hyperamplification in naturally developing tumors of dogs. SAMPLE POPULATION: Tumor specimens from 9 dogs with tumors (rhabdomyosarcoma, osteosarcoma, chondrosarcoma, myxosarcoma, and mammary gland tumor) and 2 canine osteosarcoma cell lines. PROCEDURE: 3 antibodies for centrosome proteins (ie, anti-gamma-tubulin, anti-BRCA1, and anti-pericentrin) were used for immunohistochemical analysis. Double immunostaining for centrosomes was used to confirm the specificity of these antibodies for centrosomes. Mutational analysis of the canine p53 gene was carried out by polymerase chain reaction-single-strand conformation polymorphism analysis, and expression of canine MDM2 protein was evaluated by use of immunohistochemical analysis, using anti-MDM2 antibody. RESULTS: Immunohistochemical analysis of dog osteosarcoma cell lines with apparent aneuploidy revealed frequent hyperamplification of centrosomes in the osteosarcoma cell lines. Similar hyperamplified centrosomes were detected in the tumor tissues from all of the 9 tumors. The frequency of cells with hyperamplified centrosomes (3 to 20/cell) in each tumor tissue ranged from 9.50 to 48.1%, whereas centrosome hyperamplification was not observed in normal lymph nodes from these dogs. In 8 of the 9 tumors, mutation of p53 gene or overexpression of MDM2, or both, was detected. CONCLUSIONS AND CLINICAL RELEVANCE: Various types of naturally developing tumors in dogs often have hyperamplification of centrosomes associated with chromosome instability. Hyperamplification of centrosomes is a novel tumor marker for use in cytologic and histologic examinations of clinical specimens obtained from dogs. 相似文献