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11.
Khan MN Cho JY Lee MC Kang JY Park NG Fujii H Hong YK 《Journal of agricultural and food chemistry》2007,55(17):6984-6988
Two anti-inflammatory omega-3 polyunsaturated fatty acids (PUFAs) of stearidonic acid (SA) and eicosapentaenoic acid (EPA) and one pro-inflammatory omega-6 PUFA of arachidonic acid (AA) were isolated from the edible brown seaweed Undaria pinnatifida. SA was active against mouse ear inflammation induced by phorbol myristate acetate, with IC50 values of 160, 314, and 235 microg per ear for edema, erythema, and blood flow, respectively. EPA was also active against edema, erythema, and blood flow, with IC50 values of 230, 462, and 236 microg per ear, respectively. Although AA at low concentrations showed anti-inflammatory activities when measured 10 h later, AA doses of more than 243 microg per ear induced inflammatory symptoms 1 h later. Mature thalli generally had larger amounts of PUFAs than young thalli. The algal blade contained more omega-3 PUFAs than were found in other parts, while the holdfast contained extremely high amounts of AA. Late-season thalli showed increased amounts of PUFAs, especially AA. 相似文献
12.
Maninder Kaur Walia Yesuf Assen Mohammed 《Communications in Soil Science and Plant Analysis》2017,48(22):2652-2662
Genetic and environmental factors lead to a variation in yield and protein content of dry pea (Pisum sativum L.) seeds. The quality of seed, particularly seed vigor, also influences the establishment of crop and thus final grain yield. The area and production for dry peas are increasing in the Northern Great Plains but knowledge is lacking on how the pea lines/varieties differ in the seed vigor at seven leaf stage. This field and greenhouse study evaluated the eight dry pea lines/varieties for seedling vigor indices and correlated them with grain yield and protein concentrations. Significant differences were observed among the lines/varieties for nodule number plant?1 in greenhouse, and grain yield in field conditions. The highest number of nodules plant?1 was obtained with the line MT632, which were at par with lines MT457, and MT190. The highest Vigor Index I was achieved with line MT632 associated with their more shoot lengths as compared to other lines/varieties. The highest Vigor Index II was obtained by variety Majoret and line MT632. The variety DS Admiral yielded 5205 kg ha?1, which was 17.4 and 33.3% higher than lines MT460 and MT190, respectively. The highest seed protein content was obtained with variety Majoret (23.4%) having highest Vigor Index II and seed yield (4940 kg ha?1) at par with variety DS Admiral. The lowest seed protein was found with variety DS Admiral (20.3%). The line named MT190 showed lowest yield potential along with the lower protein contents also. Studies show a positive and significant correlation between biomass and Vigor Index I only. Plant nitrogen uptake was positively and significantly correlated with biomass and Vigor Index I in greenhouse only. The results also indicated that seed vigor indices did not reveal any significant correlations with dry peas yield and protein content, so more efforts are needed to evaluate varieties for higher yield and protein content during initial stages of growth in order to maximize their acreage and productivity. 相似文献
13.
Audrey G. Quentin Elizabeth A. Pinkard Christopher L. Beadle Timothy J. Wardlaw Anthony P. O’Grady Stephen Paterson Caroline L. Mohammed 《Annals of Forest Science》2010,67(2):203-203
14.
15.
We studied some clinical, biochemical and haematological variables in Desert (Najdi) sheep acutely stressed in the course of individual road transportation, and the influence thereon of pretreatment with tyrosine. Transportation for 30 min resulted in variable but statistically insignificant increases in heart, pulse and respiratory rates. It also caused significant increases in the plasma concentration of cortisol (from 43.5 to 101.7 mmol/L) and glucose (from 3.1 to 4.5 mmol/L), and a decrease in that of magnesium (from 0.85 to 0.72 mmol/L). The endogenous thiocyanate level was unaffected. The transportation stress also decreased the haematocrit (PCV) and the number of lymphocytes, and increased the concentration of haemoglobin. Pretreatment of sheep with tyrosine at a dose of 100 mg/kg by the intravenous route significantly ameliorated the stress-induced clinical, biochemical and haematological changes. The treatment caused no overt adverse effects. 相似文献
16.
Szonyi B Kang'ethe EK Mbae CK Kakundi EM Kamwati SK Mohammed HO 《Veterinary parasitology》2008,153(1-2):172-175
The objective of the study was to identify Cryptosporidium genotypes from feces collected from urban and peri-urban dairy cattle in Nairobi, Kenya, in order to determine their zoonotic potential. DNA was extracted from 34 samples that were diagnosed positive by the modified Ziehl-Neelsen technique. Two Cryptosporidium isolates examined at the 18S rRNA locus were identified as the deer-like genotype by DNA sequencing. As public health officials are facing the difficult decision whether to allow urban livestock production because of its economic benefits and a livelihood asset to the urban communities, or to ban it for its public health risks, the finding of non-zoonotic genotypes in a smallholder dairy system has significant public health as well as economic implications that merit further investigation. 相似文献
17.
Mustapha Bakry Mohammed S. Lamhamedi Jean Caron Hank Margolis Abdenbi Zine El Abidine M’Hammed Bellaka Debra C. Stowe 《New Forests》2012,43(3):267-286
The morpho-physiological quality of seedlings is negatively affected by the wide scale use of forest soils as substrates in
developing countries. With the objective of finding long-term sustainable supply of growing media, compost was produced from
shredded branches of three fast growing species (Acacia cyanophylla (AA), Acacia cyclops (AS) and Eucalyptus gomphocephala (EG). The composting process covered three different periods over the course of a year. Pile temperatures were monitored daily
and the composts were routinely sampled and analyzed for 19 chemical variables. Although composting is feasible year-round
in arid climates, compost produced in the humid cool conditions of autumn, winter and early spring reaches the maturation
phase more quickly than compost produced under hot, dry summer conditions. It also requires less turning and water. The evolution
of the composting process and quality of the final product can be assessed using three chemical variables (C/N, pH, EC). Seed
germination rates in the three types of compost were similar to that in a peat:vermiculite substrate and vigorous high quality
seedlings were produced in the two acacia composts. However, compost-grown seedlings had significantly smaller shoots and
root systems than those produced in peat substrate. Principal components analyses showed that the quality of a compost-based
substrate is reproducible and that its final chemical composition can be predicted from its raw organic materials. The EG composts had higher pH than the acacia composts, whereas the AA and EG composts were higher in mineral salts than the AS. 相似文献
18.
Abstract In an attempt to identify appropriate feeding rates for multispecies of fish raised in fertilized earthen ponds, the present work was conducted over a 19‐week experimental period to establish the growth performance, production and body composition of Nile tilapia, common carp and silver carp fed 0.0%, 0.5%, 1.0%, 3.0%, 5.0% biomass and to apparent satiation (treatments). Twelve ponds were stocked with a similar number and weight of each fish species. Two ponds were assigned to each of the treatments, and a 25% protein pelleted fish feed was used to feed fish at the specified rate of feeding. At the end of the experiment, growth, weight gain, survival, yield and body composition of fish groups were affected by the treatments. The economic effectiveness also varied among treatments. The most conspicuous attribute of the feeding rates was its lack of influence on growth (g day?1), weight gain (g per fish), yield (kg ha?1) or body composition of silver carp. The results of whole‐body proximate analysis indicated that various feeding rates had either an irregular pattern or no effects on the protein and ash gain per 100 g of fish body weight (bw) gain. The most notable exceptions were significant (P < 0.05) increases in body fat and gross energy gains in Nile tilapia, common carp and silver carp accompanied by decreases in percentages of moisture (but not in silver carp) as feeding rate increased. Among the six different feeding levels, feeding to apparent satiation (feed amount was equivalent to 2.67% of fish bw day?1) appeared to be optimal, as it significantly (P < 0.05) supported the highest fish production, income and net profit compared with all other treatments except for the 3% feeding level, for which the differences in those measurements were comparable. 相似文献
19.
Photosynthetic light acclimation in red pine (Pinus resinosa Ait.) seedlings was examined in a greenhouse study to better understand the physiological response of this species to increased light intensity following release from competition. Seedlings grown in a high (HL), medium (ML) or low (LL) light environment for 12 weeks were transferred to high light. Gas exchange and chlorophyll fluorescence of ML and LL seedlings were measured prior to and following transfer and compared with the HL control treatment. Photosynthetic characteristics were related to initial light treatment and time after transfer. Acclimation of gas exchange features to high light in shade formed ML and LL foliage was relatively rapid, with similar values among light treatments within 57 days of transfer. Acclimation of net photosynthetic rate was similar in ML and LL seedlings, and was associated primarily with increased mesophyll conductance to CO2. The ratio of variable to maximal chlorophyll fluorescence (Fv/Fm) decreased initially after transfer, especially in LL seedlings, but recovered to normal values after 57 days. Red pine seedlings appear to be well adapted for photosynthetic acclimation to high light intensity, consistent with that reported for other early successional tree species. 相似文献
20.
Elevated ultraviolet‐B (UV‐B; between 290 and 320 nm) radiation, because of depletion of the stratospheric ozone layer, is one of the major environmental factors influencing plant metabolic processes and yield. The southern US rice cultivars contribute greatly towards US rice production, but the effects of elevated UV‐B radiation on these cultivars are not well known. The objective of this study was to determine the effects of elevated UV‐B radiation on leaf photosynthetic rate (Pn), membrane stability, pollen viability, phenolic concentration and yield of eight commercially popular southern US rice cultivars (five inbred cultivars and three hybrids). Plants were grown in a temperature‐controlled greenhouse in Beaumont, TX, USA, and were exposed to UV‐B radiation of 0, 8 or 16 kJ m?2 day?1 for 90 days. For most of the cultivars, plants grown under 8 or 16 kJ UV‐B radiation showed significant decreases in Pn, membrane stability, pollen viability, and yield compared with the plants grown under an UV‐B‐free environment, whereas there was a significant increase in leaf phenolic concentration under 16 kJ UV‐B radiation. The hybrid ‘Clearfield XL729’ performed best among the selected southern US rice cultivars under 16 kJ UV‐B radiation. 相似文献