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231.
This study investigated whether reducing agents such as quercetin and iron(II) facilitate formation of nitric oxide (NO) gas from orally ingested nitrite in an vivo study. When 3 mg/kg Na (15)NO2 was orally administered to rats with or without iron(II) or quercetin, Hb (15)NO, which is indicative of systemic (15)NO, was detected in the blood, with the maximum blood concentration of Hb (15)NO at 15 min after nitrite or nitrite plus quercetin treatment, whereas after administration of nitrite plus iron(II) or nitrite plus iron(II) and quercetin, the time was shortened to 10 min. Interestingly, iron(II), quercetin, or iron(II) plus quercetin did not affect the total amount of Hb (15)NO generated from orally administered Na (15)NO2. However, the systemic nitrite concentration was significantly decreased in the presence of iron(II) or iron(II) plus quercetin. These results may indicate that iron(II) is critical to the generation of NO gas from nitrite, whereas quercetin contributed little under the in vivo experimental conditions.  相似文献   
232.
The antioxidative property of a hydrophilic extract prepared from the fruiting body of edible mushroom ( Flammulina velutipes) was evaluated. The mushroom extract contained ergothioneine (ERT) at a level of 3.03 +/- 0.07 mg/mL, showed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and suppressed lipid oxidation of bigeye tuna meat more effectively than authentic L-ERT added at the same concentration. The authentic L-ERT had stronger total reducing power than the mushroom extract and inhibited the formation of metmyoglobin (metMb) more significantly in bigeye tuna meat. Lipid oxidation in beef and fish meats to which the mushroom extract had been added was "virtually" controlled during storage on ice. Ground beef and bigeye tuna meat with the extract added kept their natural colors unchanged for longer than 12 and 7 days of ice storage, respectively. Contrary to this, browning in meat color was observed in the control samples without the extract after 6 and 2 days of storage, respectively, when stored under similar conditions. There was significant correlation between meat color and chemical parameters, including total lipid hydroperoxides, thiobarbituric acid reactive substances, and metMb. However, there was no significant correlation between pH value and meat discoloration. These results suggest that ERT in the hydrophilic extract of F. velutipes plays an important role as a color stabilizer of meats.  相似文献   
233.
Chinese cabbage yellows caused by Verticillium dahliae and V. longisporum is one of the most economically important diseases in Japan. Verticillium isolates from infected Chinese cabbage in Japan were identified as V. dahliae and V. longisporum based on morphological characteristics and newly developed molecular genotyping methods using group I intron of 18S rDNA, mitochondrial-SSU rDNA and cob gene. Although the two species were equally virulent to Chinese cabbage in the greenhouse, V. longisporum was more virulent in the field compared with V. dahliae. Among the 67 Verticillium isolates from Chinese cabbage, 53 were V. longisporum and considered to be the major pathogen. The isolation frequency of V. longisporum was 98?% in Ibaraki and eastern Gunma where Chinese cabbage was cropped from autumn to winter. In contrast, the frequency was 48?% in Nagano and north to west Gunma where the plant was cropped in cool summer and highland conditions and the rests were V. dahliae. This is the first report to show the different geographical distribution of V. longisporum and V. dahliae in Chinese cabbage production area of Japan.  相似文献   
234.
Ecological literature on abalone Haliotis discus hannai populations is reviewed to identify processes and factors driving ontogenetic shifts in habitat. Abalone recruitment is related to the algal community type, with abalone shifting with growth from deeper crustose coralline algal (CCA) habitats to shallower kelp bed habitats via algal turfs. Timing of the habitat shifts is linked to ontogenetic changes in diet, from benthic diatoms to a diet dominated by macroalgae. Susceptibility to predation appears to change, concomitant with the shift from cryptic microhabitats during early-life stages to more exposed habitats during latter-life stages. Interstitial spaces between cobbles and boulders in the CCA habitat are considered to be important for reducing predation risk. The loss of CCA nursery habitat through sedimentation and macroalgal overgrowth likely negatively affects abalone recruitment. Preservation of diverse algal communities, including suitable habitats for the different abalone growth stages, is critical for successful abalone recruitment.  相似文献   
235.
The Japanese sea cucumber Apostichopus japonicus plays important ecological and economic roles in the coastal areas of Japan. Here, we aim to reveal the relation between habitat characteristics and density of juvenile and adult sea cucumbers in Maizuru Bay. Density of adult sea cucumbers was estimated by underwater visual surveys and bottom trawls and that of newly settled individuals by seedling collectors distributed in the bay. The physical environment of the sea bottom was evaluated from median diameter, total organic carbon, total nitrogen, carbon-to-nitrogen ratio, carbon isotope ratio, nitrogen isotope ratio, depth, slope, and distance from the coastline. Adult sea cucumber density was higher in the east side than the west side of Maizuru Bay, the former having a no-take zone for sea cucumbers. Juvenile sea cucumbers were most abundantly collected in the central part of the bay. High organic matter from the sea, short distance from the coastline, and high seabed gradient (steepness) had a positive effect on the density of adult sea cucumbers, and depth had positive effects on their body size. We suggest that sustainable management of sea cucumbers can be achieved by a combination of the establishment of no-take zones and increased protection of nursery habitats.  相似文献   
236.
An amphiphilic hexa-peri-hexabenzocoronene self-assembles to form a pi-electronic, discrete nanotubular object. The object is characterized by an aspect ratio greater than 1000 and has a uniform, 14-nanometer-wide, open-ended hollow space, which is an order of magnitude larger than those of carbon nanotubes. The wall is 3 nanometers thick and consists of helical arrays of the pi-stacked graphene molecule, whose exterior and interior surfaces are covered by hydrophilic triethylene glycol chains. The graphitic nanotube is redox active, and a single piece of the nanotube across 180-nanometer-gap electrodes shows, upon oxidation, an electrical resistance of 2.5 megohms at 285 kelvin [corrected]. This family of molecularly engineered graphite with a one-dimensional tubular shape and a chemically accessible surface constitutes an important step toward molecular electronics.  相似文献   
237.
We examined the geographical variation of the skull size and shape of the lesser mouse deer (Tragulus javanicus) from Laos, Thailand, Peninsular Malaysia, Sumatra, Java, Borneo, Langkawi and some Islands of Tenasserim in Myanmar. Although the influence of the climatic condition on skull size was not confirmed in the mainland populations, the skull became rostro-caudally longer in the populations of Tenasserim and Sumatra because of island isolation effect. The skull size was classified into the following three clusters of localities from the matrix of Q-mode correlation coefficients: 1) Langkawi and Tenasserim, 2) Laos and Thailand, 3) Sumatra and Borneo. The skulls in the population of Java belong to the cluster of Langkawi and Tenasserim in male, however were morphologically similar to those in the cluster of Borneo and Sumatra. The canonical discriminant analysis pointed out that the Laos and Tenasserim populations were separated from the other ones and that the populations of Sumatra, Java and Borneo were intermingled each other.  相似文献   
238.
Automated ribotyping classified 70 Erysipelothrix species strains, previously classified into 14 RAPD patterns and into 63 PFGE patterns, into 27 ribogroups. Twenty-three strains of the 70 analyzed and classified into 13 ribogroups were previously classified into six ribotypes by the traditional ribotyping method. Moreover, automated ribotyping differentiated seven strains that were not differentiated by PFGE. Therefore, automated ribotyping was more sensitive than RAPD and traditional ribotyping, and it might be a useful method for a rapid screening in epidemiological study of strains of this genus, and more accurate results can be obtained when this method is used together with PFGE.  相似文献   
239.
A Denacol EX-313 (Denacol)-treated bovine venous graft and an ultrafine polyester fiber (UFPF) graft were transplanted as patch graft into the right ventricular outflow tract under extracorporeal circulation in six dogs each experimentally. Hemodynamics in right heart and histological findings around the graft were compared between both groups over a period of one year after grafting. Pressure measurements and angiocardiography were performed through a cardiac catheter. Right ventricular pressure, pulmonary artery pessure, and right ventricle to pulmonary artery gradient were within normal limits in both groups at 1, 2, 3, 4, 6, and 12 months or more after grafting. No difference were seen between the values for the Denacol and the UFPF group. Histologically, the medial surface at the site of grafting was covered with vascular endothelial cells at one month after grafting in both groups. The density of the vascular endothelial cells increased with time after grafting, showing no clear difference between the two groups. Subendothelial layers comprised of collagen fibers, elastic fibers, and inflammatory cells decreased with time in both groups, but there was less cell infiltration in the Denacol group than in the UFPF group at all time points after grafting. In addition, the central cut thickness value of the graft tended to be thinner in the Denacol group than in the UFPF group at all observation time points after grafting. In the Denacol group, very slight metaplasia of cartilage was noted in a portion of the graft margin at six months or more after grafting, but no other abnormalities were observed. These results suggest that the Denacol-treated bovine venous graft has better grafting characteristics than the UFPF graft with easier intra-operative handlings and less tissue reactions after grafting.  相似文献   
240.
Chrysanthemum chlorotic mottle viroid (CChMVd) was detected in Akita Prefecture, Japan, from chrysanthemums (Dendranthema grandiflorum) with distinct yellow leaf mottling and necrosis. The four clones are 398–399 nucleotides long and are thought to be the symptomatic type based on their UUUC sequence at positions 82–85 in the CChMVd tetraloop.The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession numbers AB181857–AB181860  相似文献   
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