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21.
This work is focused on the chemical characterization of Maytenus ilicifolia extracts obtained from high-pressure CO2 extraction. The experiments were performed in a laboratory-scale unit, where the effect of particle size (35-200 mesh), CO2 mass flow rate (1-3 g/min), temperature (293-323 K), pressure (100-250 bar), and extraction time was investigated in terms of liquid yield and chemical composition of the extracts. Results show that the particle size and CO2 mass flow rate did not affect the liquid yield, whereas the extraction temperature and solvent density exerted a pronounced effect on both liquid yield and chemical distribution of volatile compounds. The extracts were chemically analyzed with regard to phytol, squalene, vitamin E, stigmasterol, friedelan-3-ol, friedelin, dodecanoic acid and geranyl acetate in a GC/MSD.  相似文献   
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Rog B. Parsons 《Geoderma》1978,21(1):25-39
The development and distribution of soils in the Coast Range and Klamath Mountains are related to geomorphic surfaces and slope gradients. Soils over basalt, studied in the Coast Range, were formed in transported materials and include examples of more than a half dozen great groups of the Alfisol, Inceptisol, Mollisol, and Ultisol orders. Distribution patterns of the soils can be related to active slopes, metastable slopes, pediments, ridge tops, flood plains, and alluvial fans. Variables among the factors of soil formation in the Coast Range are chiefly geomorphic surfaces and parent materials.Soils of a lithosequence of pyroclastics, granite and schist in the Klamath Mountains include examples of great groups in the Entisol, Inceptisol, and Mollisol orders. All soils from pyroclastics have argillic horizons, those from granite lack argillic horizons, and those from schist lack argillic horizons except on relatively stable surfaces. Average thicknesses of soils over saprolite range from 76 cm over granite and schist to 150 cm over pyroclastics.Lithologic discontinuities are common in both mountain areas. Field techniques for identification, described briefly, include stone lines, irregular distribution of rock fragments with depth, thicknesses of weathering rinds on rock fragments, and the lateral extensions of soil horizons.  相似文献   
24.
Management of a traumatic oronasal fistula with a prosthetic device in an 8-year-old male neutered domestic shorthair cat is described. The animal had fallen from a height of three stories at the age of 1 year. The fall had resulted in a fracture of the hard palate and a split in the palatal mucosa. Two surgical attempts to close the defect had been unsuccessful and an autopolymerizable acrylic resin prosthesis had produced unsatisfactory results. The management of the chronic traumatic fistula with a conical prosthetic device was fast, easy and efficient. The device was removed and a second one was put in place after 2 years. This method would appear particularly useful for obturation of large palatal defects that have failed to heal after attempts at surgical closure and is an alternative treatment for debilitated cats which may not be candidates for longer surgical procedures.  相似文献   
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This study evaluated the effect of methionine supplementation, predation risk and their interaction on gut histology, whole-body cortisol levels, and intestinal gene expression in zebrafish. A total of 360 one-year-old animals were maintained under two environmental conditions and fed diets containing different methionine sources. Fish were fed either a control diet (CTL, without methionine supplementation), a diet supplemented with dl -methionine (DLM), or a diet supplemented with methionine dipeptide (MM) in the absence (AP) of a predator or in the presence of the predator (PP) for 48 h or 20 days. Predator-induced stress for 20 days resulted in lower body weight. Zebrafish fed methionine-supplemented diets had higher weight gain than control fish. We found no effect of predation stress or methionine supplementation on cortisol level. Predation risk and methionine supplementation showed no interaction effect on dipeptide transporter gene expression. After 48 h of predation pressure, zebrafish had higher mRNA expression of SOD2, CAT and GPX1 in the gut. After 20 days of exposure to the predator, zebrafish fed methionine-supplemented diets had lower expression of GPX1, SOD2 and CAT than those diet CTL. Methionine dipeptide and free methionine supplementation improved growth, intestinal health and survivability of zebrafish both conditions.  相似文献   
27.
Horses are hosts to a wide variety of helminthes; the most important are the cyathostomin, or small strongyles. The viability of a fungal formulation (pellets) using the nematode-trapping fungus Monacrosporium thaumasium was assessed in biological control of horse cyathostomin. Two groups (fungus-treated and control) consisted of six mares in each group, crossbred (ages of 2.5 and 3.5 years), were placed in pastures of Cynodon sp. naturally infected with horse cyathostomin larvae. In the treated group, each animal received 1g/10 kg body weight (0.2g/10 kg live weight of fungus) of pellets of sodium alginate matrix containing the fungus M. thaumasium orally, twice a week for 6 months. In the control group, animals received (1g/10 kg body weight) of pellets without fungus. The egg count per gram of feces showed difference (p<0.01) in the animals treated with the fungus in relation to the control animals during all months of the experiment. The EPG percentage decrease were 87.5%, 89.7%, 68.3%, 58.7%, 52.5% and 35.2% during June, July, August, September, October and November, respectively. In faecal cultures, there was difference (p<0.05) among animals treated with fungus was found in relation to the control animals during all the experiment month, with percentage reduction of 67.5%, 61.4% and 31.8% in September, October and November, respectively. Difference (p<0.01) was observed in the recovery of infective larvae from pastures that were collected up to 20 cm from the dung pats in pastures in the group treated with the fungus in relation to the control group with a reduction of 60.9% and between 0-20 and 0-40 cm from the faecal pat reduction (p<0.01) was about 56% in the group treated with the fungus M. thaumasium in relation to the control group pasture. There was no difference (p>0.05) between the average weight gains in both animal groups. The treatment of horses with pellets containing the nematophagous fungus M. thaumasium can be effective in controlling cyathostomin in the tropical region of southeastern Brazil.  相似文献   
28.
This study aimed to evaluate the potential of soybean-promoted acidic nitrite reduction and to correlate this activity with the content of phenolics and with the bactericidal activity against Escherichia coli O157:H7. Extracts of embrionary axes and cotyledons enriched in phenolics increased ?NO formation at acidic pH at values that were 7.1 and 4.5 times higher, respectively, when compared to the reduction of the nonenriched extracts. Among the various phenolics accumulated in the soybean extracts, five stimulated nitrite reduction in the following decreasing order of potency: epicatechin gallate, chlorogenic acid, caffeic acid, galic acid and p-coumaric acid. Extracts of embrionary axes presented higher contents of epicatechin gallate and caffeic acid, compared to that of cotyledons, indicating a positive correlation between activity of the extracts and content of phenolics with regard to nitrite reducing activity. Soybean extracts enriched in phenolics interacted synergistically with acidified nitrite to prevent E. coli O157:H7 growth. The results suggest that soybean phenolics may interfere with the metabolism of ?NO in an acidic environment by accelerating the reduction of nitrite, with a potential antimicrobial effect in the stomach.  相似文献   
29.
The purpose of this study was to evaluate the tissue response to a 70% polyhydroxybutyrate and 30% hydroxyapatite composite in the form of a bone implant, placed intracortically in the distal metaphyseal of the right femur, and subcutaneous implants in cats. Samples of the composite were implanted subcutaneously in the dorsolumbar region and the distal metaphyseal region of the right femur of the animals. The study used 12 neutered adult mixed breed cats, weighing an average of 3.5kg. The cats were randomly divided into three groups: GI, GII and GIII, according to the length of the assessment period. The assessments of their subcutaneous and bone tissues were performed at 15, 30 and 45 days and at 30, 60 and 90 days, respectively. The subcutaneous and bone reactions to the composites were characterized by granulomatous inflammation with a predominance of macrophages and giant cells. The results showed that the composites triggered a chronic local inflammatory response, despite their clinical acceptance.  相似文献   
30.
This study reports on the cross-species amplification of 23 microsatellite markers previously developed for Theobroma cacao L. (Sterculiaceae), source of chocolate in three economically important Amazonian species of Theobroma (T. grandiflorum, T. subincanum, T. sylvestre). Thirteen of the 23 microsatellite loci tested were polymorphic across the three species at 2–13 alleles per locus. The observed heterozygosity per locus varied from 0.18 to 0.84 and expected heterozygosity ranged from 0.28 to 0.87. The high level of transferability and genetic information content of these microsatellite loci indicate their usefulness for population genetic, mating system and breeding studies of these economically important Amazonian fruit trees.  相似文献   
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