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51.
52.
Taguchi H Watanabe S Temmei Y Hirao T Akiyama H Sakai S Adachi R Sakata K Urisu A Teshima R 《Journal of agricultural and food chemistry》2011,59(8):3510-3519
Shrimp and crab are well-known as allergenic ingredients. According to Japanese food allergy labeling regulations, shrimp species (including prawns, crayfishes, and lobsters) and crab species must be differentially declared when ≥10 ppm (total protein) of an allergenic ingredient is present. However, the commercial ELISA tests for the detection of crustacean proteins cannot differentiate between shrimp and crab. Therefore, two methods were developed to discriminate shrimp and crab: a shrimp-PCR method with postamplification digestion and a crab-PCR method that specifically amplifies a fragment of the 16S rRNA gene. The sensitivity and specificity of both PCR methods were verified by experiments using DNA extracted from 15 shrimp species, 13 crab species, krill, mysid, mantis shrimp, other food samples (cephalopod, shellfish, and fish), incurred foods, and commercial food products. Both PCR methods could detect 5 pg of DNA extracted from target species and 50 ng of genomic DNA extracted from incurred foods containing 10 ppm (μg/g) total protein of shrimp or crab. The two PCR methods were considered to be specific enough to separately detect species belonging to shrimp and crab. Although false-positive and false-negative results were obtained from some nontarget crustacean species, the proposed PCR methods, when used in conjunction with ELISA tests, would be a useful tool for confirmation of the validity of food allergy labeling and management of processed food safety for allergic patients. 相似文献
53.
Izumi Noguchi Takunori Katoh Shigekatsu Sakai Riki Iwata Masayuki Akiyama Hideyuki Ohtsuka Kouichi Sakata Hirohide Aga Yutaka Matsumoto 《Water, air, and soil pollution》2001,130(1-4):421-426
Snowcover surveys were carried out in Hokkaido, northern Japan. Snowpack samples were collected using a steel pipe at 80 sites in 1988, 69 sites in 1992, and 66 sites in 1996 and 2000 during the time when the water equivalents of the snowcover are the greatest. Spatial distribution maps of water equivalents and of the concentrations and the accumulated amounts of hydrogen, non-sea-salt sulfate and non-sea-salt calcium ion of the snowcover drawn by Kriging method are discussed. The distribution maps show that water equivalents and the accumulated amounts of hydrogen and non-sea-salt sulfate in all the sample years were largest in the Japan Sea region, as were the ion concentrations of hydrogen and non-sea-salt sulfate. It was estimated this was caused by air pollutants transported from a great distance. The ratio of areas below pH 5.0 increased temporally from 1988 (20%) to 1992, 1996 and 2000 (66–80%). This trend was estimated to be affected by a decline of non-sea-salt calcium concentrations derived from alkaline road dust. In addition, the effect of snowcover components was assessed by comparison between the acid loads of the snowcover and the acid neutralizing capacity of lake water. We found that lakes in the middle of the Japan Sea coast have the potential to be acidified by snowmelt. 相似文献
54.
Takaya Y Kondo Y Furukawa T Niwa M 《Journal of agricultural and food chemistry》2003,51(27):8061-8066
Methanol extracts of 11 kinds of commonly available vegetables were examined for hydroxyl radical scavenging potency using the bleomycin-Fe method. In this method, the iron ion and bleomycin in water form hydroxyl radicals, and the scavenging activity is monitored by the modified thiobarbituric acid method. All extracts showed scavenging capacity, even though the activity of some of them was lower than that of l-ascorbic acid. Those vegetables were classified into three groups according to their activity, groups showing strong activity, moderate activity, and weak activity, as compared to the activity of l-ascorbic acid at the same concentration. Among them, the methanol extract of radish sprout (Japanese name "kaiware-daikon") exhibited the highest potency (1.8 times as l-ascorbic acid). Then, we investigated the constituents of the methanol extract of radish sprout and the contribution to the overall activity of each compound by examining their activity. As the result, several kinds of sinapinic acid esters and flavonoids were isolated with high radical scavenging potency, which must contribute substantially to the activity. 相似文献
55.
To determine the geological distribution of acid buffering capacity and exchangeable Al of forest soils in Japan, surface soils under forest vegetation were collected nationwide from a total of 1,034 sites. Generally, surface soils in Japanese forests are mostly acidic and low in both exchangeable cation content and exchangeable Al. The median of soil pH(H2O), total exchangeable cations, and exchangeable Al are 5.1, 76 mmol(+)Kg?1, and 19.6 mmol(+)kg?1, respectively. Acid buffering capacities of selected soils were determined using a soil column, which was comparable to the capacity that resulted from cation exchanges with protons. Soils with high buffering capacity and low exchangeable Al are widely distributed in Japan, and overlap with the areas of Andisol distribution. Volcanogenic materials seem to mask soil characteristics derived from underlying geology even though they are not Andisols. However, central to western Honshu Island, Shikoku Island, and northern Kyushu Island showed weak acid buffering capacities with high exchangeable Al potential in surface soils. 相似文献
56.
Hiroshi Hara Moritsugu Kitamura Atsuko Mori Izumi Noguchi Tsuyoshi Ohizumi Sinya Seto Tadashi Takeuchi Teruyuki Deguchi 《Water, air, and soil pollution》1995,85(4):2307-2312
Precipitation chemistry in Japan was discussed on a wet-only sample database obtained in a nationwide survey from April 1989 to March 1993. Wet-only samples were collected at 29 stations over Japan on a biweekly basis. Commonly determined chemical parameters were measured in laboratories. The volume-weighted annual mean pH at each site ranged from 4.50 to 5.83 with a mean of 4.76. Concentration ranges and means (parenthesized) on an equivalent basis for major ions were as follows: nss-SO4
2–; 5.2–58.9 (38.6), NO3
–; 1.8–25.0 (14.1), NH4
+; 0.55–29.8 (18.3), nss-Ca2+; 2.0–34.5(14.2), Na+; 6.4–275.3 (49.1), Cl–; 13.7–322.4 (63.5) eq L–1. Acid-base relationships for Phase-II records were quantitatively discussed in terms of three measures: pH, fractional acidity, and our proposed pAi. 相似文献
57.
Nozaki H Wijayagunawardane MP Kodituwakku SP Yoshida T Nakamura T Arai I Urashima T Miyamoto A 《The Journal of reproduction and development》2005,51(2):229-234
N-acetylglucosaminyltransferase I (GnT I; EC 2.4.1.101), which catalyzes the first step in the conversion of oligomannose to complex or hybrid N-glycans of glycoproteins, was found in media cultured with bovine oviduct epithelial cells (BOEC) obtained from non-pregnant cows during the follicular phase. Combined treatment with specific hormones increased GnT I release from BOEC. Luteinizing hormone (LH; 10 ng/ml) alone slightly, but together with 17beta-estradiol (E2; 1 ng/ml), synergistically increased GnT I activity. Vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF) alpha, which have been shown to have their highest activities in the bovine oviduct during the periovulatory period, also increased in GnT I activity. This study provides the first evidence of an increase of GnT I release from BOEC in vitro, and shows that endocrine as well as local factors such as LH, VEGF and TNFalpha increase this activity. The results suggest that GnT I activity in the bovine oviduct may contribute to the induction of glycosylation and thereby contributing to the provision of the optimal microenvironment for fertilization and early development of the embryos. 相似文献
58.
Itoh N Muraoka N Saeki H Aoki M Itagaki T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(7):717-718
Giardia intestinalis antigen in fecal samples was examined in 361 dogs of 14 breeding kennels located at various areas in Japan, using a commercial enzyme-linked immunosorbent assay (ELISA) kit. G. intestinalis antigen was detected in 37.4% of the fecal specimens. All of the 14 breeding kennels were positive for G. intestinalis antigen with the range from 6.7 to 59.3%. The prevalence in puppies (54.5%) was significantly (p < 0.01) higher than that in adults (30.9%). There was no difference in prevalence between males and females, and between the puppies from the mother dogs positive and negative for Giardia antigen. In conclusion, G. intestinalis widely invaded the breeding kennels in Japan. 相似文献
59.
Miyama T Sakata Y Shimada Y Ogino S Watanabe M Itamoto K Okuda M Verdida RA Xuan X Nagasawa H Inokuma H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(5):467-471
To determine the distribution of Babesia gibsoni infection in dogs in the eastern part of Japan, an epidemiological survey of dogs suspected of having B. gibsoni infection was attempted using the polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA). Thirty-five of 115 such dogs (30.4%) were positive by PCR and/or ELISA. The 35 positive dogs consisted of 28 Tosa dogs, 4 American Pit Bull Terriers, and 3 mongrel dogs in Aomori, Fukushima, Ibaraki, Gunma, Chiba, Tokyo, Kanagawa, and Nagano Prefectures. The positive dogs had a significantly lower rate of tick exposure and a higher rate of bites by other dogs. Twenty-two of 35 B. gibsoni-positive dogs were infected with hemoplasma, and the rate of infection was significantly higher than that of B. gibsoni-negative dogs. 相似文献
60.
Abe S Mukai T Hirata N Barnouin-Jha OS Cheng AF Demura H Gaskell RW Hashimoto T Hiraoka K Honda T Kubota T Matsuoka M Mizuno T Nakamura R Scheeres DJ Yoshikawa M 《Science (New York, N.Y.)》2006,312(5778):1344-1347
The ranging instrument aboard the Hayabusa spacecraft measured the surface topography of asteroid 25143 Itokawa and its mass. A typical rough area is similar in roughness to debris located on the interior wall of a large crater on asteroid 433 Eros, which suggests a surface structure on Itokawa similar to crater ejecta on Eros. The mass of Itokawa was estimated as (3.58 +/- 0.18) x 10(10) kilograms, implying a bulk density of (1.95 +/- 0.14) grams per cubic centimeter for a volume of (1.84 +/- 0.09) x 10(7) cubic meters and a bulk porosity of approximately 40%, which is similar to that of angular sands, when assuming an LL (low iron chondritic) meteorite composition. Combined with surface observations, these data indicate that Itokawa is the first subkilometer-sized small asteroid showing a rubble-pile body rather than a solid monolithic asteroid. 相似文献