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排序方式: 共有186条查询结果,搜索用时 46 毫秒
61.
Agbor GA Oben JE Ngogang JY Xinxing C Vinson JA 《Journal of agricultural and food chemistry》2005,53(17):6819-6824
This study evaluates the antioxidant capacity of 14 herbs/spices from Cameroon. Freeze-dried samples extracted in methanol (free or unconjugated polyphenol) and in 1.2 M hydrochloric acid (HCl) in methanol (total antioxidant that is both unconjugated and conjugated) were analyzed using two different antioxidant assay methods [Folin-Ciocalteu reagent (Folin) and the ferric reducing antioxidant power (FRAP)]. The 1.2 M HCl in methanol extracts had significantly higher (P < 0.001) antioxidant capacities than the methanolic extract. Generally, the FRAP antioxidant values were significantly (P < 0.001) higher than the Folin antioxidant values. Although a significant correlation (P < 0.05) was obtained between the Folin phenol and the FRAP antioxidant, the trends of the antioxidant capacity of the samples were different for the Folin and FRAP methods. The leaves of the Piper species top the total antioxidant tables in both Folin and FRAP assay methods, respectively. Irvingia gabonensis tops the FRAP free antioxidant list, while Piper umbellatum leads the Folin free antioxidant followed by Thymus vulgaris. Thus, the antioxidant capacity of plant samples determined by different methods should be interpreted with caution. However, irrespective of the assay method used, the samples were rich in antioxidants. 相似文献
62.
Delmar R. Finco DVM PhD Clarence A. Rawlings DVM PhD Wayne A. Crowell DVM PhD Scott A. Brown VMD Jeanne A. Barsanti DVM MS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1987,1(2):61-66
Sixteen mongrel dogs had bilateral nephrectomy and received a renal allograft from an unmatched mongrel. One group of eight dogs was treated orally with azathioprine and prednisone; another group of eight dogs was treated orally with cyclosporine and prednisone. Four dogs of each group received four blood transfusions each prior to surgery. Mean survival time was nearly the same in the azathioprine-treated and the cyclosporine-treated dogs. Transfusions prolonged survival in the azathioprine-treated group but not in the cyclosporine-treated group. Retrospective measurement of whole blood trough cyclosporine concentrations indicated marked variation between dogs and in the same dog at different times. This variation may have influenced graft survival. Only one dog survived the 9-month period of observation, indicating that refinements of the techniques used in this study will be required for long-term survival of renal allografts in unrelated mongrel dogs. 相似文献
63.
64.
Bangou MJ Kiendrebeogo M Meda NT Coulibaly AY Compaoré M Zeba B Millogo-Rasolodimby J Nacoulma OG 《Pakistan journal of biological sciences: PJBS》2011,14(2):99-105
The aim of the present study was to evaluate some enzymes inhibitory effects of 11 plant species belonging to 9 families from Burkina Faso. Methanolic extracts were used for their Glutathione-s-transferase (GST), Acetylcholinesterase (AChE), Carboxylesterase (CES) and Xanthine Oxidase (XO) inhibitory activities at final concentration of 100 microg mL(-1). The total phenolics, flavonoids and tannins were also determined spectrophotometrically using Folin-Ciocalteu, AlCl3 and ammonium citrate iron reagents, respectively. Among the 11 species tested, the best inhibitory percentages were found with Euphorbia hirta, Sclerocarya birrea and Scoparia dulcis (inhibition > 40%) followed by Annona senegalensis, Annona squamosa, Polygala arenaria and Ceratotheca sesamoides (inhibition > 25%). The best total phenolic and tannin contents were found with S. birrea with 56.10 mg GAE/100 mg extract and 47.75 mg TAE/100 mg extract, respectively. E hirta presented the higher total flavonoids (9.96 mg QE/100 mg extract). It's was found that Sclerocarya birrea has inhibited all enzymes at more than 30% and this activity is correlated to total tannins contents. Contrary to S. birrea, the enzymatic activities of E. hirta and S. dulcis are correlated to total flavonoids contents. Present findings suggest that the methanolic extracts of those plant species are potential inhibitors of GST, AChE, CES and XO and confirm their traditional uses in the treatment of mental disorders, gout, painful inflammations and cardiovascular diseases. 相似文献
65.
Tim McCleary Mary McAllister Mark Coggeshall Jeanne Romero-Severson 《Genetic Resources and Crop Evolution》2013,60(4):1209-1222
Over the last two centuries, chestnut breeding programs in Europe and Asia have generated an array of chestnut interspecific hybrids, primarily of European (Castanea sativa), Japanese (C. crenata) and Chinese (C. mollissima) ancestry. During this same period, Europeans colonizing North America imported hybrid chestnuts and made interspecific hybrids with native chestnuts, primarily American chestnut (C. dentata). The importation of Chinese chestnut into the United States in the late 19th century also introduced chestnut blight, which triggered an additional interspecific hybridization effort in an attempt to develop blight resistant American chestnuts. Chestnut cultivars used for nut production in the United States and Canada have arisen against this background of non-native introductions and extensive hybridizing. The development of regionally adapted nut producing trees with dependable crops of high quality nuts requires sorting out the identities of existing cultivars. We chose 11 EST-SSR markers from C. mollissima for the initial task of genotyping 65 chestnut cultivars that grow well in the central United States. Many of these cultivars have interspecific pedigrees involving two or more species. We found extensive homonymies and synonymies, genetic groups inconsistent with published pedigrees, contradictory pedigrees and evidence for incorrect species assignments. Accurate inference of the interspecific ancestries of cultivars grown in the United States and Canada will require genotyping of species reference sets for C. sativa, C. crenata, C. mollissima, C. dentata and possibly C. pumila (the Ozark and Allegheny chinquapins). 相似文献
66.
Cultivation of Burgundy black truffles (Tuber aestivum syn. T. uncinatum) in Midwestern agroforestry has the potential to provide important income not only to landowners, but also to the hospitality industry. Economically viable harvest depends upon both successful seedling colonization by the truffle fungus and successful growth of the fungus along with the extending root system. We evaluated an established hybrid oak (Quercus bicolor × Q. robur) truffière 5 and 6 years after planting in May 2005, to evaluate the effects of three seedling production methods on tree growth and root colonization by T. aestivum. Oak seedlings produced using two variations on the RPM© (Root Production Method) substrate grew significantly faster in height and diameter, but were significantly less well colonized by the truffle fungus compared with saplings from seedlings produced by the “Typical” method. We found that 0.7–19.8 % of root tips (mean 5.1 %) sampled from saplings grown from Typical seedlings were colonized by T. aestivum. By 2010, two distinct canopy forms had developed: ‘upright’ versus ‘spreading’. Although root colonization was not related to canopy form, future fruit body production may be influenced by the greater soil shading provided by the spreading canopy form. A comparison of autumn/winter air temperatures in Missouri, USA with European conditions suggests that fruit body production in Missouri will likely be greatest from mid-September through mid-December. Soil pH modification by application of crushed limestone prior to planting was effective in maintaining average pH at 7.16 through 2010, a level consistent with fruit body production. 相似文献
67.
Jeanne Stoltz 《African Zoology》2013,48(1):361-365
Baboon infants were captured with their mothers in the Loskopdam area. The infants were separated from their mothers and raised in a laboratory. Each infant was placed with a surrogate mother. The infants accepted their surrogate mothers immediately. The very young infants spent most of their time with the mother where they suckled and slept for long periods. The older infants spent less time with their mothers. They only returned to the mother to be fed, to sleep or when frightened. The surrogate mothers that we have designed satisfied the needs of the infant. Thus infants were raised successfully in the laboratory. 相似文献
68.
Effect of water surface condition on survival,growth and swim bladder inflation of yellowfin tuna,Thunnus albacares (Temminck and Schlegel), larvae
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Tomoki Honryo Teruyoshi Tanaka Angel Guillen Jeanne B Wexler Amado Cano Daniel Margulies Vernon P Scholey Maria S Stein Yoshifumi Sawada 《Aquaculture Research》2016,47(6):1832-1840
Early‐stage mortality due to surface water tension‐related death and due to sinking to the tank bottom was investigated for yellowfin tuna, Thunnus albacares (YFT), larvae. Different aeration rates and rearing water surface conditions were examined to evaluate the effect on larval survival, swim bladder inflation and growth. The percentage survival of yolk sac larvae was significantly higher when the rearing water surface was covered with fish oil at aeration rates of 0 and 50 mL min?1. The highest mortality occurred at the highest aeration rate of 250 mL min?1 regardless of surface water condition. A second experiment was conducted twice under different water surface conditions: the water surface was covered by fish oil (FO), skimmed of fish oil (SS), and was not treated (NC). The percentage survival was not significantly different between treatments after 7 days of feeding. In contrast to the survival, the proportion of larvae with inflated swim bladders was significantly higher for the NC and SS groups than that of the FO group. Results of these experiments indicate that the addition of oil to the rearing water surface without its removal interferes with the initial swim bladder inflation in YFT larvae. These results also indicate that YFT larvae need to obtain (gulp) air at the water surface for initial swim bladder inflation, and success of initial swim bladder inflation may be crucial for their survival. 相似文献
69.
70.
Finno C Pusterla N Aleman M Mohr FC Price T George J Holmberg T 《Journal of the American Veterinary Medical Association》2006,229(5):721-724
CASE DESCRIPTION: A 4-month-old American Paint Horse colt was evaluated because of acute onset of ataxia, left-sided head tilt, and fever and a recently noticed heart murmur. Upper respiratory tract infection caused by Streptococcus equi subsp equi had been diagnosed at 3 months of age. CLINICAL FINDINGS: Hematologic abnormalities included leukocytosis, mature neutrophilia, monocytosis, and mild anemia. Analysis of a CSF sample revealed high total protein concentration and total nucleated cell count; nucleated cells consisted mainly of degenerate neutrophils. Results of a real-time PCR assay were positive for S equi subsp equi, and a diagnosis of S equi subsp equi meningoencephalomyelitis was made. TREATMENT AND OUTCOME: Treatment included administration of potassium penicillin and fluids, but the foal developed uroperitoneum and was subsequently euthanized. Postmortem examination revealed meningoencephalomyelitis, and S equi subsp equi was cultured from a brain aspirate. Additional findings included suppurative cystitis with rupture and neutrophilic myocarditis. CLINICAL RELEVANCE: Findings suggest that S equi subsp equi meningoencephalomyelitis should be considered in the differential diagnosis for foals with neurologic signs that have a history of strangles or exposure to affected horses. 相似文献