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31.
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
32.
Bioassay-guided fractionation using different chromatographic and spectroscopic techniques in the analysis of the Red Sea soft coral Litophyton arboreum led to the isolation of nine compounds; sarcophytol M (1), alismol (2), 24-methylcholesta-5,24(28)-diene-3β-ol (3), 10-O-methyl alismoxide (4), alismoxide (5), (S)-chimyl alcohol (6), 7β-acetoxy-24-methylcholesta-5-24(28)-diene-3,19-diol (7), erythro-N-dodecanoyl-docosasphinga-(4E,8E)-dienine (8), and 24-methylcholesta-5,24(28)-diene-3β,7β,19-triol (9). Some of the isolated compounds demonstrated potent cytotoxic- and/or cytostatic activity against HeLa and U937 cancer cell lines and inhibitory activity against HIV-1 protease (PR). Compound 7 was strongly cytotoxic against HeLa cells (CC50 4.3 ± 0.75 µM), with selectivity index of SI 8.1, which was confirmed by real time cell electronic sensing (RT-CES). Compounds 2, 7, and 8 showed strong inhibitory activity against HIV-1 PR at IC50s of 7.20 ± 0.7, 4.85 ± 0.18, and 4.80 ± 0.92 µM respectively. In silico docking of most compounds presented comparable scores to that of acetyl pepstatin, a known HIV-1 PR inhibitor. Interestingly, compound 8 showed potent HIV-1 PR inhibitory activity in the absence of cytotoxicity against the cell lines used. In addition, compounds 2 and 5 demonstrated cytostatic action in HeLa cells, revealing potential use in virostatic cocktails. Taken together, data presented here suggest Litophyton arboreum to contain promising compounds for further investigation against the diseases mentioned. 相似文献
33.
Minicucci LA Hanson KA Olson DK Hueston WD 《Journal of veterinary medical education》2008,35(2):166-172
As a result of the growing need for public-health veterinarians, novel educational programs are essential to train future public-health professionals. The University of Minnesota School of Public Health, in collaboration with the College of Veterinary Medicine, initiated a dual DVM/MPH program in 2002. This program provides flexibility by combining distance learning and on-campus courses offered through a summer public-health institute. MPH requirements are completed through core courses, elective courses in a focus area, and an MPH project and field experience. Currently, more than 100 students representing 13 veterinary schools are enrolled in the program. The majority of initial program graduates have pursued public-practice careers upon completion of the program. Strengths of the Minnesota program design include accessibility and an environment to support multidisciplinary training. Continued assessment of program graduates will allow for evaluation and adjustment of the program in the coming years. 相似文献
34.
In the horse, conventional inactivated or subunit vaccines against equine influenza virus (EIV) induce a short-lived antibody-based immunity to infection. Alternative strategies of vaccination have been subsequently developed to mimic the long-term protection induced by natural infection with the virus. One of these approaches is the use of immune-stimulating complex (ISCOM)-based vaccines. ISCOM vaccines induce a strong antibody response and protection against influenza in horses, humans, and a mouse model. Cell-mediated immunity (CMI) has been demonstrated in humans and mice after ISCOM vaccination, but rarely investigated in the horse. The aim of this study was to evaluate EIV-specific immune responses after intra-muscular vaccination with an ISCOM-EIV vaccine (EQUIP F) containing both equine influenza H7N7 (A/eq/Newmarket/77) and H3N8 (A/eq/Borl?nge/91 and A/eq/Kentucky/98) strains. The antibody response was measured by single radial haemolysis (SRH) assay using different H3N8 EIV strains. Stimulation of type-1 immunity was evaluated with a recently developed method that measures EIV-specific IFNgamma synthesis by peripheral blood lymphocytes (PBL). The protective efficacy of this ISCOM-based vaccine against challenge infection with a recent equine influenza (H3N8; A/eq/South Africa/4/03) strain was also evaluated. Vaccinated ponies developed elevated levels of EIV-specific SRH antibody and increased percentage of EIV-specific IFNgamma(+) PBL, whereas these responses were only detected after challenge infection in unvaccinated control ponies. Vaccinates showed minimal signs of disease and did not shed virus when challenged shortly after the second immunisation. In conclusion, evidence of type-1 immunity induced by an ISCOM-based vaccine is described for the first time in horses. 相似文献
35.
36.
Burton EC Miller DL Styer EL Gray MJ 《Veterinary journal (London, England : 1997)》2008,177(3):442-444
During an on-going amphibian ecology study, a free-ranging American bullfrog (Rana catesbeiana) metamorph was captured in a pitfall trap adjacent to a constructed farm pond at the Plateau Research and Education Center (PREC) on the Cumberland Plateau near Crossville, Tennessee, USA. Grossly, the right eye was approximately 50% the size of the left. Stereo and light microscopic examination revealed two granulomas within the orbit. Electron microscopic examination revealed virus particles scattered throughout one structure but mostly aggregated toward the center. Subsequent PCR and sequencing (GenBank accession Number EF175670) confirmed frog virus 3 (FV3). This represents the first report of a malformation in an anuran associated with FV3. 相似文献
37.
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39.
Simpson BS Landsberg GM Reisner IR Ciribassi JJ Horwitz D Houpt KA Kroll TL Luescher A Moffat KS Douglass G Robertson-Plouch C Veenhuizen MF Zimmerman A Clark TP 《Veterinary therapeutics : research in applied veterinary medicine》2007,8(1):18-31
Canine separation anxiety is a common behavioral problem presented to veterinarians. Associated behaviors are distressing to both dog and owner, have the potential to disrupt the human-companion animal bond, and may lead to euthanasia. The results of this study demonstrate the clinical efficacy and safety of Reconcile (fluoxetine, 1 to 2 mg/kg/day [0.45 to 0.91 mg/lb/day]), in conjunction with behavior management, for the treatment of canine separation anxiety. The beef flavored chewable formulation was palatable to treated dogs and easy to administer. This study provides to veterinarians and owners valuable information about an effective separation anxiety treatment plan that combines use of Reconcile with behavior modification. 相似文献
40.
Nine Prunus accessions were evaluated for germination and plantlet growth in an in vitro osmotic screening test using mannitol
as an osmoticum. Embryos from diverse peaches, almonds and peach-almond hybrids were cultured in Woody Plant Medium, and in
this same medium modified with the inclusion of 350 mM mannitol. Embryos were stratified in vitro for 60 days, induced to
germinate for a two week period and then allowed to develop and grow for another 20 days prior to harvest. Fresh weights of
both roots and shoots as well as percent germination were recorded at harvest. The main effects of nutrient medium, germplasm
type (peach, peach-almond, almond) and specific Prunus accession were all highly significant (P = 0.01) with regard to fresh
weight of roots and shoots. Embryo germination was affected significantly by the inclusion of mannitol in the nutrient medium
and by the particular germplasm type (P=0.01 and P=0.05, respectively). Significant interactions of nutrient medium × Prunus
accession and nutrient medium × germplasm type were also detected for both root and shoot fresh weights. Almond germplasm
cultured in Woody Plant Medium with 350 mM mannitol produced significantly more roots and shoots than either peaches or peach-almond
hybrids grown in the same medium. Peach-almond hybrid embryos were observed to germinate at a significantly higher frequency
than peach embryos when averaged across both media. Results obtained in this study indicate a wide range of average plantlet
fresh weight relative to the specific germplasm challenged in the osmotic screen.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献