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排序方式: 共有49条查询结果,搜索用时 93 毫秒
1.
This study was designed to obtain information on the residual influence of dietary monensin on ruminant fermentation, methanogenesis and bacterial population. Three ruminally cannulated crossbreed heifers (14 months old, 363 ± 11 kg) were fed Italian ryegrass straw and concentrate supplemented with monensin for 21 days before sampling. Rumen fluid samples were collected for analysis of short chain fatty acid (SCFA) profiles, monensin concentration, methanogens and rumen bacterial density. Post‐feeding rumen fluid was also collected to determine in vitro gas production. Monensin was eliminated from the rumen fluid within 3 days. The composition of SCFA varied after elimination of monensin, while total production of SCFA was 1.78 times higher than on the first day. Methane production increased 7 days after monensin administration ceased, whereas hydrogen production decreased. The methanogens and rumen bacterial copy numbers were unaffected by the withdrawal of monensin.  相似文献   
2.
Antitumor activity of compounds isolated from leaves of Eriobotrya japonica   总被引:3,自引:0,他引:3  
In a search for possible antitumor agents from natural sources, megastigmane glycosides and polyphenolic constituents isolated from the leaves of Eriobotrya japonica (Rosaceae) were found to inhibit the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced activation of Epstein-Barr virus early antigen in Raji cells. Roseoside and procyanidin B-2 were among the active compounds found in an in vitro assay; these compounds were further assessed for antitumor activity in vivo in a two-stage carcinogenesis assay on mouse skin. Roseoside significantly delayed carcinogenesis induced by peroxynitrite (initiator) and TPA (promoter), and its potency was comparable to that of a green tea polyphenol, (-)-epigallocatechin 3-O-gallate, in the same assay.  相似文献   
3.
Kimura Y  Sumiyoshi M 《Fitoterapia》2011,82(6):827-833
The Swertia japonica is used clinically as a remedy for gastrointestinal symptoms in Japan. We examined the effects of a S. japonica and swertiamarin on gastric emptying and gastrointestinal motility in atropine-, dopamine-, and 5-hydroxytryptamine (5-HT)-treated mice. All three preparations inhibited reductions in gastric emptying and gastrointestinal motility induced by dopamine (1 mg/kg, intraperitoneal injection, ip). Neither the powder, swertiamarin, nor itopride had any effect on the reductions in gastric emptying and gastrointestinal motility caused by 5-HT (4 mg/kg, ip). These findings suggest that the powder and swertiamarin stimulate gastric emptying and gastrointestinal motility by inhibiting the dopamine D2 receptor.  相似文献   
4.
The Japanese crested ibis Nipponia nippon is a critically threatened bird. Accurate sexing is necessary to perform effective management of captive breeding toward a national project for a tentative release of the Japanese crested ibis on Sado Island. A PCR‐based sexing method targeting a 0.6 kb EcoRI fragment (EE0.6) sequence on W chromosome with AWS03 and USP3 primers has been developed for the Japanese crested ibis. However, the primers were selected from the EE0.6 sequences from bird species other than the Japanese crested ibis. In this study, we determined the W‐ and Z‐linked EE0.6 sequences in the Japanese crested ibis, and clarified Japanese crested ibis sequence mismatch in the binding sites of the primers. Further, we found no polymorphism in the primer binding sites among five founder birds for the Sado captive Japanese crested ibis population. These findings validated the PCR‐based sexing method with the AWS03 and USP3 as accurate molecular sexing methods of captive Japanese crested ibis on the Sado Island. Additionally, we designed a primer set for a novel PCR‐based sexing, based on the EE0.6 sequences obtained in this study. This novel sexing method may be useful for future ecological research following the release of Japanese crested ibis on Sado Island. This is the first report to show the EE0.6 sequences in Japanese crested ibis.  相似文献   
5.
We investigated the effects of warming the basal ends of Carolina poplar (Populus × canadensis Moench.) softwood cuttings at controlled low-air-temperature on their root growth and leaf damage after planting. The warming treatment was applied to the cuttings by soaking 10 mm beyond the cut end in warmed water maintained at 30 °C in a cold chamber maintained at an air temperature of 10 °C and a photosynthetic photon flux density (PPFD) of 10 μmol m?2 s?1 (near the light compensation point at 10 °C) until rooting was observed. The warmed cuttings were then grown in a growth chamber at an air temperature of 30 °C, relative humidity 85–90 %, and a PPFD of 100 μmol m?2 s?1. Control cuttings were grown in the growth chamber throughout the experiment. Rooting occurred simultaneously for both warmed and control cuttings, irrespective of air temperature. Root development was greater and leaf damage, evaluated on the basis of extent of necrosis, was less for warmed cuttings than for control cuttings. The reduction of leaf damage for warmed cuttings probably resulted from reduced post-planting water stress and leaf senescence, because of improved root development as a result of the pre-planting warming treatment. This technique could improve the propagation of cuttings of woody plants, because it would ensure that the cuttings are ready to develop roots with minimum loss of carbohydrates, irrespective of weather conditions.  相似文献   
6.
It has been reported that epigallocatechin-3-O-(3″-O-methyl)-gallate (EGCG3″Me) and the EGCG3″Me-rich green tea ( Camellia sinensis L.) cultivar 'Benifuuki' exhibit antiallergic effects. The objective of this study was to investigate the effect of various tea leaf catechins on histamine release from murine bone marrow mast cells (BMMC). At a dose of 50 μg/mL, the rank order of histamine release inhibition was observed to be epicatechin-3-O-(3″-O-methyl)-gallate (ECG3″Me) > gallocatechin-3-O-(3″-O-methyl)-gallate (GCG3″Me) > EGCG3″Me > gallocatechin-gallate (GCG) > catechin-gallate (CG) > EGCG > epicatechin-gallate (ECG) > epigallocatechin (EGC) > gallocatechin (GC). Of the various tea cultivars analyzed by HPLC, the greatest content of ECG3″Me was found in the third crop of 'Benifuuki' (1.05% dry weight). Moreover, ECG3″Me content was positively correlated with EGCG3″Me content in 'Benifuuki' tea leaves. In an assay of mixtures of ECG3″Me and EGCG3″Me, inhibitory activity (50 μg/mL in total) was increased as the content of ECG3″Me increased. This suggests that ECG3″Me might link to the antiallergic effect of 'Benifuuki' tea, as has been reported for EGCG3″Me.  相似文献   
7.
The in vitro reactivity of capsanthin (1) and fucoxanthin (2) with peroxynitrite was investigated, and the reaction products produced by scavenging with peroxynitrite were analyzed. (14'Z)-Nitrocapsanthin (3) and 12-nitrocapsanthin (4) were isolated from the products of the reaction of capsanthin with peroxynitrite. Similarly, (14Z)-15-nitrofucoxanthin (5), (11Z)-11-nitrofucoxanthin (6), and (14Z,9'Z)-15-nitrofucoxanthin (7) were obtained from the reaction of peroxynitrite reaction with fucoxanthin. Capsanthin and fucoxanthin inhibited the nitration of tyrosine by peroxynitrite. Furthermore, nitrocapsanthins (3 and 4) and nitrofucoxanthins (5 and 6) exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and an antiproliferative effect on human pancreatic carcinoma. Moreover, nitrocapsanthins (3 and 4) inhibited carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene (DMBN).  相似文献   
8.
20Alpha-hydroxysteroid dehydrogenase (20alpha-HSD) catalyzes the conversion of progesterone to its inactive form 20alpha-dihydroprogesterone (20alpha-OHP). 20Alpha-HSD is expressed in the murine placenta, suggesting a role, yet unidentified, played by this enzyme during the course of pregnancy. To elucidate the possible roles of 20alpha-HSD during pregnancy, 20alpha-HSD gene expression in the placenta was examined by Northern blot analysis, and progestin (progesterone and 20alpha-OHP) concentrations in the maternal and fetal sera and the amniotic fluid were measured by radioimmunoassay in pregnant Shiba goats. The expression of 20alpha-HSD mRNA was observed in the placenta and the intercaruncular part of the uterus during mid to late pregnancy. Analysis by in situ hybridization revealed that 20alpha-HSD mRNA was mainly localized in the endometrial epithelium of the caruncle side of the placenta. Considerable enzyme activity of 20alpha-HSD was also detected in the cytosolic fraction of the placenta and intercaruncular part of the uterus. Although concentrations of progesterone and 20alpha-OHP in the maternal serum showed similar profiles, progesterone levels in the fetal serum stayed extremely low throughout the pregnancy. The 20alpha-OHP concentration in the fetal serum was always higher than that in the maternal serum. In the amniotic fluid, the concentrations of both progesterone and 20alpha-OHP remained at very low levels throughout the pregnancy. These results support the notion that 20alpha-HSD protects the fetus from the cytotoxic effects of progesterone, and thereby maintains the normal development of the fetus.  相似文献   
9.
10.
Tea cultivars have been bred by individual selection of landraces and by crossbreeding, but the validation of the parentage is limited. In this study, we performed parentage analysis of 79 tea cultivars in Japan based on SSR markers to confirm or identify the parent-offspring relationships among them. The effectiveness of nine SSR markers for parentage analysis was validated by comparing them to the existing cleaved amplified polymorphic sequence markers. The former markers were detectable more alleles than the latter. Simulation of parentage analysis of the tea cultivars predicted biparental origins for 12 cultivars (‘Houshun’, ‘Mie ryokuhou no. 1’, ‘Surugawase’, ‘Tenmyo’, ‘Yamanoibuki’, ‘Harumidori’, ‘Koushun’, ‘Minekaori’, ‘Okumusashi’, ‘Saemidori’, ‘Sofu’, and ‘Toyoka’), in the first five of which candidate parents of yet-to-be-defined pedigree were newly identified. Comparisons of a total of 41 SSR genotypes confirmed the newly-identified parentages of ‘Asahi’ for ‘Tenmyo’, ‘Rokurou’ for ‘Houshun’, ‘Surugawase’, and ‘Yamanoibuki’, and ‘Yamatomidori’ for ‘Mie ryokuhou no. 1’. The maternity of seven cultivars out of the 12 was also confirmed with chloroplast DNA sequences. Uniparental origins were confirmed for 25 cultivars. This parentage analysis has improved our knowledge of tea pedigrees and will aid in the development of new cultivars.  相似文献   
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