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排序方式: 共有753条查询结果,搜索用时 15 毫秒
731.
732.
H. Akagi O. Malm F. J. P. Branches Y. Kinjo Y. Kashima J. R. D. Guimaraes R. B. Oliveira K. Haraguchi W. C. Pfeiffer Y. Takizawa H. Kato 《Water, air, and soil pollution》1995,80(1-4):85-94
To obtain the basic information on human exposure to mercury (Hg) due to gold mining activities in Amazon, total mercury (T-Hg) and methylmercury (MeI Ig) were determined for human hair, blood and/or urine samples collected from populations living in gold mining area and fishing villages upstream of the Tapajos River basin. Abnormally high levels of T-Hg were observed in hair and blood from all fishing villages investigated and more than 90% of T-Hg was in the form of MeHg in both samples, whereas in goldrnining area the value were much lower and the %MeHg values varied widely (20–100%) with individuals even in blood samples. Urine from gold shop workers contained Hg mostly in inorganic form at 165μg/g creatinine on the average, with the range of 20 to 450μg/g creatinine. A good correlation between Hg in hair and blood was found in fishing villages and the ratios of hair Hg to blood Hg were very close to 250, generally established for MeHg. T-Hg and inorganic Hg levels in urine from gold shop workers were also significantly correlated with inorganic Hg in blood. 相似文献
733.
The antigenic and allergenic activities of ovomucoid (OM) remaining in soluble fractions of pasta-like model samples of wheat flour mixed with egg white were investigated by ELISA competitive inhibition and immunoblotting analyses using a rabbit anti-OM IgG and the serum IgE specific for OM in patients allergic to egg white. The mixture of egg white and wheat flour of soft, hard, and durum varieties was kneaded for 10-50 min and benched for 1 h at RT, and then small pieces of the dough were heated in boiling 1% NaCl solution for 15 min. Even before heating, only after the kneading for 30 min or more, but not after kneading for only 20 min, followed by the benching, the antigenic activity of OM which remained in the phosphate-buffered saline extract from the dough markedly decreased. Almost no antigenic activity of OM was detected in the extracts of heated samples. Furthermore, in the extracts of heated durum samples, only a trace of or almost no IgE-reactive OM was detected against the five patients' sera. These reductive effects of wheat on the OM antigenicity and allergenicity were more remarkable in the durum variety than in the others. No detectable proteins were extracted with 1% SDS from the heated samples, whereas OM was extracted with 1% SDS containing 10% 2-mercaptoethanol, suggesting heat-induced polymerization through intermolecular disulfide bonds among OM and wheat. 相似文献
734.
Haraguchi M Gorniak SL Ikeda K Minami Y Kato A Watson AA Nash RJ Molyneux RJ Asano N 《Journal of agricultural and food chemistry》2003,51(17):4995-5000
Natural intoxication of livestock by the ingestion of Ipomoea carnea (Convolvulaceae) sometimes occurs in tropical regions of the world. Polyhydroxylated alkaloids were isolated from the leaves, flowers, and seeds of the poisonous plant and characterized. Chromatographic separation of the leaf extract resulted in the isolation of swainsonine (1), 2-epi-lentiginosine (2), calystegines B(1) (3), B(2) (4), B(3) (5), and C(1) (6), and N-methyl-trans-4-hydroxy-l-proline (7). The contents of 1 in the fresh leaves and flowers were 0.0029 and 0.0028%, respectively, whereas the contents of 1, 3, and 4 in the seeds were approximately 10 times higher than those in the leaves and flowers. Alkaloids 3, 4, and 6 showed a potent inhibitory activity toward rat lysosomal beta-glucosidase, with IC(50) values of 2.1, 0.75, and 0.84 microM, respectively, and alkaloid 5 was a moderate inhibitor of alpha- and beta-mannosidases. Although alkaloid 1 is known as a powerful inhibitor of lysosomal alpha-mannosidase (IC(50) = 0.02 microM), alkaloid 2, which has been thought to be an intermediate in the biosynthesis of 1, was also a potent inhibitor of alpha-mannosidase with an IC(50) value of 4.6 microM. 相似文献
735.
Makoto Kondo Randi Mulianda Masaya Matamura Toshiyuki Shibata Takashi Mishima Anuraga Jayanegara Naoto Isono 《Animal Science Journal》2021,92(1):e13530
Soluble sugars in feeds are important for ruminant production; however, performing numerous sugar analyses within a short period is a laborious task. Here, we developed a phenol-sulfuric acid (PSA) assay in a microplate format to quantify soluble sugars in ruminant feeds. This method is easy and quick and requires only a small quantity of harmful reagents. We found that assay measurements were not affected by the representative organic acids and sugar alcohol contained in feeds. The treatment of activated charcoal with ethanol extract prior to the PSA assay was effective in removing interfering compounds for a more accurate determination of soluble sugars in certain feeds. Furthermore, the inter-day and intra-day repeatability of the present method was acceptable. Hence, we conclude that the method developed in this study is suitable for routine analysis of soluble sugars content in ruminant feeds. 相似文献
736.
Hiromichi Ohtsuka Misa Ohsawa Kenji Murakami Ryo Murata Toshihide Kato Motoshi Tajima 《Canadian journal of veterinary research》2021,85(1):72
Changes in immune factors expressed by milk somatic cells from Holstein cows with hypocalcemia after calving were investigated in this study. Fourteen multiparous Holstein cows after their 3rd or 4th calving in one farm were used. The cows were divided into 2 groups: 7 cows needing treatment due to onset of hypocalcemia (hypocalcemia group; age = 5.53 ± 0.27 years, parity = 3.14 ± 0.14) and 7 cows without health problems (control group; age = 5.88 ± 0.31 years, parity = 3.57 ± 0.26). Milk samples were collected aseptically using a cannula and mRNA of immune factors expressed by milk somatic cells were analyzed. Milk samples (50 mL) were collected from the right rear mammary gland of cows before milking at day 1 and weeks 1, 2, 4, and 8 after calving. All milk samples showed a negative reaction to the California Mastitis Test. Levels of relative interleukin (IL)-6 and cathelicidin in the hypocalcemia group were lower than those in the control group in weeks 1 to 8. A significant difference in relative IL-6 levels was found in week 4 (P < 0.05). These results suggest that levels of IL-6 expressed by milk somatic cells may be affected by hypocalcemia in dairy cows. 相似文献
737.
Germination response in wheat grains to dihydroactinidiolide,a germination inhibitor in wheat husks,and related compounds 总被引:2,自引:0,他引:2
Kato T Imai T Kashimura K Saito N Masaya K 《Journal of agricultural and food chemistry》2003,51(8):2161-2167
On the basis of our recent findings that the germination of intact wheat grains with glumes (husks) belonging to dormant varieties was restrained as compared with that of dehusked grains, we have explored the identities of germination inhibitors in the glumes, resulting in the characterization of dihydroactinidiolide (1) and some aromatic compounds. A related natural product, tetrahydroactinidiolide (2), showed similar activity. The present study has demonstrated that the sensitivity in inhibition response of germination of the grains to 1 and 2 declined during after-ripening, in parallel with changes in germinability; the sprouting of after-ripened seeds on a whole spike was preventable by exogenous application of 2 in laboratory conditions, and germination of after-ripened grains was delayed by more than two weeks by the action of 1 or 2. The term "pseudodormancy" is proposed for the phenomenon of delay of germination caused by the inhibitor. After accumulation of additional evidence on inhibition response of actinidiolide-type natural products, structurally related to inhibitor 1, a mechanism concerning germination inhibition by 1 or 2 is proposed on the basis of the concept of nonbonding interaction with the inhibitors at an active site of an acceptor. 相似文献
738.
Hormonally active chemicals (HACs) that are capable of inducing adverse effects on wildlife as well as human beings are featured as "endocrine disruptors". Various animal studies conducted to clarify the characteristics of HACs, including the uterotrophic assay, are sufficiently sensitive to detect the effect of 17-beta-estradiol in micrograms per kilogram of body weight or lower. In such systems, a trace amount of HACs in the dietary pellets may interfere with the test results and thus can be a serious problem for the low-dose issue, which is now a major topic in the field of endocrine disruptor research. Here, the significance of the hormonal effects of phytoestrogen components in the NIH-07 diet is confirmed and a NIH-07-based open formula "phytoestrogen-low diet" (PLD) is proposed, which effectively reduces uterine weight as well as the uterine luminal epithelial labeling index in ovariectomized rats. 相似文献
739.
Keiko Hamaguchi Kenryu Kato Kojiro Esaki Naoto Kamata 《Journal of Forest Research》2011,16(6):518-521
The ambrosia beetle, Platypus quercivorus, is an insect vector for the causal agent of Japanese oak wilt disease, Raffaelea quercivora. We have developed 10 new polymorphic microsatellite markers from Type 1, one of the genetic types of the beetle, using a
biotin-enrichment procedure. Fifty-three adult beetles were used for characterization of the markers. The number of alleles
per locus ranged from two to nine (average 4.9). The observed and expected heterozygosity ranged from 0.49 to 0.77 and from
0.44 to 0.80, respectively. None of the loci deviated significantly from Hardy–Weinberg equilibrium. No linkage disequilibrium
was detected in any pairwise comparisons of loci. Most of the markers successfully amplified in other genetic types of the
beetle. These markers could become useful tools for population genetic studies and for parentage and sibship analysis for
this beetle. 相似文献
740.
Timing of acorn development and abortion is an important maternal strategy in oak sexual reproduction. To understand the significance
of acorn abortion in Quercus serrata, artificial pollination of different mating patterns (outcross, self-, and nonpollination) was performed, and the timing
of abortion and the size and internal development of acorns from each mating type were investigated. Acorns were aborted similarly
in every pollination treatment until 80 days after pollination. Almost all self- and nonpollinated acorns were rapidly aborted
during the period 80–120 days after pollination. During that period, differences in internal fruit development between outcross-pollinated
and unsuitably pollinated (self- and nonpolinated) acorns were observed. In addition, cotyledon development and a rapid increase
in fruit size were observed in the acorns gained by outcross pollination. The correspondence between the timing of abortion
and the timing of rapid size growth and the development of storage organs suggests that this acorn-maintenance strategy may
be the consequence of a maternal adaptation that allows better reproductive success under resource limitation. 相似文献