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121.
Polymorphisms in the prion protein gene ( PRNP ) are known to be associated with transmissible spongiform encephalopathies in human, sheep and goats. There is tentative association between PRNP promoter polymorphism and bovine spongiform encephalopathy (BSE) susceptibility in cattle. In this study, we genotyped for six bovine PRNP polymorphic sites including a 23-bp indel in the promoter, a 12-bp indel in the intron 1, two nonsynonymous single nucleotide polymorphisms (SNPs), octapeptide repeats in the coding region and a 14-bp indel in the 3'-untranslated region in 178 animals representing Japanese Brown, Kuchinoshima feral, Mishima, Japanese Shorthorn and Holstein. In 64 Japanese Brown cattle, three indel sites were polymorphic. All of the six sites were monomorphic in Kuchinoshima. The 23-bp and 12-bp indel sites were polymorphic in Mishima cattle. The 23-bp and 14-bp indel sites were polymorphic in Japanese Shorthorn cattle. Both SNP sites were monomorphic in all cattle examined in this study. At the 23-bp indel site, the genotype frequencies of Japanese Brown and Holstein breeds were similar to that of BSE affected cattle. We estimated 12 different haplotypes from these genotypic data. A '23-12-K6S14+' haplotype was the major haplotype in all populations, whose frequencies ranged from 0.50 to 1.00.  相似文献   
122.
123.
Plant foods and herbal sources of resveratrol   总被引:11,自引:0,他引:11  
Stilbenes, in particular trans-resveratrol and its glucoside, are widely reported to be beneficial to health, having been shown to possess antioxidative, anticarcinogenic, and antitumor properties. Major dietary sources include grapes, wine, peanuts, and soy; however, they can also be introduced into the diet through Itadori tea, which has long been used in Japan and China as a traditional herbal remedy for heart disease and strokes. Analysis of grapes, peanuts, and Itadori tea shows that they contain mainly trans-resveratrol glucoside. In contrast, red wines are primarily a source of the aglycones cis- and trans-resveratrol. While peanuts and grapes contain low levels of the stilbenes, Itadori tea and red wine both supply relatively high concentrations of resveratrol. For people who do not consume alcohol, Itadori tea may be a suitable substitute for red wine. However, further study on the potential biological effects of other endogenous compounds in Itadori tea is required and there is also a need for more information on the absorption and in vivo biomedical actions of free and conjugated resveratrol.  相似文献   
124.
This study determined isotopic fractionation of nitrate-nitrogen during denitrification in riparian aquifer sediments by sequential-column experiments at two different water flow rates. The purpose was to discuss the relationships of nitrogen isotopic enrichment factor of denitrification, denitrification rate, and infiltrating condition in sediment. Sandy sediment and groundwater were collected from floodplain in the middle reach of the Tama River where nitrogen isotopic enrichment factor for denitrification had been measured in a result of previous field observation. The denitrification rates and the isotopic enrichment factors of nitrate-nitrogen were estimated at 2.1 mgN dry-kg?1 day?1 and ?32.9‰ during the low water flow condition, and at 3.5 mgN dry-kg?1 day?1 and ?34.1‰ during the high water flow condition. The calculated water flow rates of the present column experiments were 300–400 times higher than that of the field observation. Because of the fast flow rate, nitrate was expected to continuously pass though active denitrifying sites in the small pore spaces of sediment, and nitrate supply to denitrifers by infiltration flow transport greatly exceeded the supply by diffusion. The observed denitrification rates was proportional to Peclet number as the ratio of solute nitrate transport to the diffusion, and apparent nitrogen isotopic enrichment factors during denitrification of our column experiments were lower than those obtained from the field observation. This study showed that denitrification rate and apparent nitrogen isotopic enrichment factor of denitrification in sediment depended on Peclet number.  相似文献   
125.
OBJECTIVE: To identify effects of revision of the Japanese food composition tables from the fourth version to the fifth version on nutrient intake estimation. DESIGN: A database on 783 samples of 24-hour food duplicate portions was re-visited. Nutrients in the duplicate portions were estimated by use of the fourth and fifth versions of the Japanese food composition tables in parallel, together with supplemental use of other databases. The two sets of estimates were subjected to comparison. SETTING: The sample collection was conducted at 31 sites all over Japan. SUBJECTS: The sample donors were 783 women aged 20-78 years. RESULTS: Compared with the estimates by use of the fourth version of the tables, the estimates by the fifth version were substantially higher for intakes of energy, carbohydrate, dietary fibre, vitamin A and niacin, and lower for iron intake. The increase in carbohydrate intake estimates was more evident in older women than in young women, whereas the decrease in the intake estimation of iron and the increase in that of dietary fibre were more marked in young women than in older women. CONCLUSION: The recent revision of food composition tables in Japan induced substantial changes in the estimation of nutrient intakes, i.e. an increase in energy, carbohydrate, dietary fibre, vitamin A and niacin, and a decrease in iron. The extent of the changes varied depending on age.  相似文献   
126.
127.
We determined the sequence of the immunoglobulin gamma heavy‐chain constant (IGHC) region of the Mongolian gerbil (Meriones unguiculatus). To isolate a part of the IGHC complementary DNA, we designed primers on the basis of highly conserved sequences in mouse, rat and hamster. The deduced IGHC is structurally similar to counterparts in other mammalian species and shows 84.6% identity to the IGHC of hamster IgG, 76.6% to rat IgG1, 83.3% to rat IgG2a, 78.1% to mouse IgG1, 81.8% to mouse IgG2a, 79.1% to mouse IgG2b and 79.2% to mouse IgG3 at the nucleotide level. The results suggest that gerbil IgG is closely related to hamster IgG and rat IgG2a.  相似文献   
128.
Twelve polar cardenolide monoglycosides, 1, 2, 4?C13, and oleagenin (3) were isolated from the methanol extract of stems and twigs of Nerium oleander. Among these, oleagenin (3) and cardenolide monoglycosides named cardenolide B-1 (1) and cardenolide B-2 (2) were isolated from natural sources for the first time. The in vitro antiinflammatory activity of compounds 1?C13 was examined on the basis of inhibitory activity against the induction of the intercellular adhesion molecule-1 (ICAM-1). Compounds 4?C7 were active at an IC50 value of less than 0.4 ??M. The cytotoxic activity of compounds 1?C13 was evaluated against three human cell lines: normal human fibroblast cells (WI-38), malignant tumor cells derived from WI-38 (VA-13), and human liver tumor cells (HepG2). Compounds 4, 6, and 7 were active toward these three cell lines at IC50 values of less than 0.7 ??M, and compounds 5 and 8 were active toward the cell lines at IC50 values of less than 1.5 ??M. The multidrug resistance (MDR) cancer-reversal activity of compounds 1?C13 was evaluated on the basis of the amount of calcein accumulated in MDR human ovarian cancer 2780AD cells in the presence of each compound. Compound 1 and 12 showed significant effects on calcein accumulation.  相似文献   
129.
The mammalian visual cortex is organized into columns. Here, we examine cortical influences upon developing visual afferents in the cat by altering intrinsic gamma-aminobutyric acid (GABA)-mediated inhibition with benzodiazepines. Local enhancement by agonist (diazepam) infusion did not perturb visual responsiveness, but did widen column spacing. An inverse agonist (DMCM) produced the opposite effect. Thus, intracortical inhibitory circuits shape the geometry of incoming thalamic arbors, suggesting that cortical columnar architecture depends on neuronal activity.  相似文献   
130.
We introduce a method to fabricate high-performance field-effect transistors on the surface of freestanding organic single crystals. The transistors are constructed by laminating a monolithic elastomeric transistor stamp against the surface of a crystal. This method, which eliminates exposure of the fragile organic surface to the hazards of conventional processing, enables fabrication of rubrene transistors with charge carrier mobilities as high as approximately 15 cm2/V.s and subthreshold slopes as low as 2nF.V/decade.cm2. Multiple relamination of the transistor stamp against the same crystal does not affect the transistor characteristics; we exploit this reversibility to reveal anisotropic charge transport at the basal plane of rubrene.  相似文献   
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