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41.
Dicko MH Gruppen H Traore AS van Berkel WJ Voragen AG 《Journal of agricultural and food chemistry》2005,53(7):2581-2588
The screening of 50 sorghum varieties showed that, on average, germination did not affect the content in total phenolic compounds but decreased the content of proanthocyanidins, 3-deoxyanthocyanidins, and flavan-4-ols. Independent of germination, there are intervarietal differences in antioxidant activities among sorghum varieties. Phenolic compounds and antioxidant activities were more positively correlated in ungerminated varieties than in germinated ones. Sorghum grains with pigmented testa layer, chestnut color glumes, and red plants had higher contents, larger diversity of phenolic compounds, and higher antioxidant activities than other sorghums. Some red sorghum varieties had higher antioxidant activities (30-80 mumol of Trolox equiv/g) than several sources of natural antioxidants from plant foods. Among varieties used for "to", "dolo", couscous, and porridge preparation, the "dolo"(local beer) varieties had the highest average content and diversity in phenolic compounds as well as the highest antioxidant activities. The biochemical markers determined are useful indicators for the selection of sorghum varieties for food and agronomic properties. 相似文献
42.
Dicko MH Hilhorst R Gruppen H Traore AS Laane C van Berkel WJ Voragen AG 《Journal of agricultural and food chemistry》2002,50(13):3780-3788
Analysis of fifty sorghum [Sorghum bicolor (L.) Moench] varieties used in Burkina Faso showed that they have different contents of phenolic compounds, peroxidase (POX), and polyphenol oxidase (PPO). Most of the varieties (82%) had a tannin content less than 0.25% (w/w). POX specific activity was higher than the monophenolase and o-diphenolase specific activities of PPO. For POX, there was a diversity of isoforms among varieties. No clear correlation could be made between the quantitative composition of the grain in phenolics, PPO, and POX, and resistance of plant to pathogens. In general, varieties good for a thick porridge preparation ("t?") had low phenolic compounds content and a medium POX activity. From the red varieties, those used for local beer ("dolo") had a high content in phenolic compounds and PPO, and a low POX activity. The variety considered good for couscous had a low POX content. The characteristics might be useful as selection markers for breeding for specific applications. 相似文献
43.
Oxidative metabolism of the soy isoflavones daidzein and genistein in humans in vitro and in vivo. 总被引:5,自引:0,他引:5
The soy isoflavones daidzein and genistein are found in high concentrations in human plasma and urine after soy consumption. However, in vitro and in vivo data regarding the oxidative metabolism of isoflavones in humans are scarce. Therefore, we have studied the oxidative metabolites of these compounds formed in human liver microsomes and excreted in urine of male and female humans ingesting soy products for 2 days. Human liver microsomes transformed the soy isoflavone daidzein to three monohydroxylated and three dihydroxylated metabolites according to GC/MS analysis. On the basis of a previous study with rat liver microsomes and with the help of reference substances, these metabolites were identified as 6,7,4'-trihydroxyisoflavone, 7,3',4'-trihydroxyisoflavone, 7,8,4'-trihydroxyisoflavone, 7,8,3',4'-tetrahydroxyisoflavone, 6,7,8,4'-tetrahydroxyisoflavone, and 6,7,3',4'-tetrahydroxyisoflavone. Significant amounts of the same metabolites except 6,7,8,4'-tetrahydroxyisoflavone were also found in urine of female and male volunteers after soy intake. Genistein was metabolized by human liver microsomes to six hydroxylation products. The main metabolites were the three aromatic monohydroxylated products 5,6,7,4'-tetrahydroxyisoflavone, 5,7,8,4'-tetrahydroxyisoflavone and 5,7,3',4'-tetrahydroxyisoflavone. The aliphatic monohydroxylated metabolite 2,5,7,4'-tetrahydroxyisoflavone and two aromatic dihydroxylated metabolites, 5,7,8,3',4'-pentahydroxyisoflavone and 5,6,7,3',4'-pentahydroxyisoflavone, were formed in trace amounts. The same hydroxylated genistein metabolites except the aliphatic hydroxylated one could also be detected in human urine samples. Methylated forms of the catechol metabolites, which were generated by incubations with catechol-O-methyltransferase in vitro could be detected only in trace amounts in the urine samples. This implies that this reaction does not play a major role in the biotransformation of the hydroxylated daidzein and genistein metabolites in vivo. Most of these oxidative metabolites are described as human in vivo metabolites for the first time. Their biological significance remains to be established. 相似文献
44.
Alfred J. Keys 《Pest management science》1983,14(3):313-316
Photorespiration in plants is defined and discussed. The possibility of increasing crop yields by controlling photorespiration, particularly by inhibiting the initial reaction, is considered. 相似文献
45.
James P. Foley DVM Alfred M. Legendre DVM MS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(6):333-334
Itraconazole, a tricyclic azole effective against a number of deep mycotic diseases, was used to treat a Quarter Horse filly with coccidioidomycosis. The horse was almost normal after 90 days of treatment. Five months after discontinuing itraconazole treatment, the filly had severe neck pain and neurologic signs from recurrence of coccidioidomycosis and was treated with itraconazole for an additional 6 months. Her clinical condition improved to almost normal and the filly has remained normal for 2 years. There was no evidence of drug toxicity. 相似文献
46.
R J Higgins S Krakowka A E Metzler A Koestner 《American journal of veterinary research》1982,43(10):1820-1824
An indirect immunocytochemical labeling technique, using horseradish peroxidase-conjugated antibody was used to detect the intracellular and surface membrane localization of canine distemper virus (R252-CDV) antigens during productive virus replication in infected Vero cells. Specific labeling of intracellular viral antigens was restricted to rough nucleocapsid aggregates. Surface membrane labeling correlated directly with the appearances both of virus-specific membrane spikes and buds and of mature virions. Syncytial cell formation was associated with labeled cytoplasmic nucleocapsid, but there was no evidence of productive CDV formation on surface membranes. The immunoperoxidase technique provided precise ultrastructural antigenic localization with concomitant preservation of excellent ultrastructural detail within single virus-infected cells during CDV replication cycle in vitro. 相似文献
47.
M Engels M Palatini A E Metzler U Probst U Kihm M Ackermann 《Veterinary microbiology》1992,33(1-4):69-78
Bovine herpesvirus 1 (BHV1) and caprine herpesvirus 1 (CapHV1) are useful models to study virus-host interactions, as well as pathogenicity and latency, when comparing the outcome of infection in the natural and the foreign hosts. Molecular seroepidemiological analyses revealed that cross-reacting antibodies were mainly induced by glycoprotein gI (gB analogue), by the major capsid protein and by nonstructural proteins, whereas the most virus-specific antibodies were elicited by glycoproteins gIII and gIV. These glycoproteins, especially gIII (gC analogue), might therefore play an important role in the virus-host-interactions. As a basis for further studies, we re-evaluated observations concerning experimental infections with BHV1 and CapHV1 in the natural and the foreign hosts. All parameters indicated that both viruses were able to infect either host, but that the pathogenicity was restricted to the natural host. Latent virus could be reactivated exclusively from cows infected with BHV1. It was possible neither to reactivate BHV1 from goats, nor to reactivate CapHV1 from either species. The experiments indicated that the outcome of infection in the natural and the foreign host is dependent on host and viral factors, whereby gIII is only one important virus component involved. Further investigations in the host and host cell range of BHV1 and CapHV1 will help to clarify the role of factors responsible for virus-host-interactions. 相似文献
48.
49.
50.
Robert K. McDonald DVM Michael Walker DVM Alfred M. Legendre DVM MS Rene T. vanEe DVM Rebecca E. Gompf DVM MS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1988,2(2):103-107
Four dogs with metastatic seminoma were treated with cesium 137 teleradiotherapy. Minimum total tumor dose ranged from 17 to 40 gray (Gy) and was usually given through bilateral opposing sublumbar ports in eight to ten fractions, with three fractions given weekly. The tumor regressed in all four dogs. The first dog (case 1) was free of tumor and died of non-tumor related causes at 57 months. The second dog (case 2) was free of tumor but was euthanatized at 37 months for a limb fracture. The third dog (case 3) was euthanatized for undertermined pulmonary disease 43 months after radiotherapy. The fourth dog (case 4) was euthanatized 6 months following radiotherapy because of transitional cell carcinoma and renal failure. No evidence of seminoma was found at necropsy. Radiotherapy was shown to be effective treatment for seminoma with regional metastasis. 相似文献