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841.
Nusbaum KE Wright JC Johnston WB Allison AB Hilton CD Staggs LA Stallknecht DE Shelnutt JL 《Avian diseases》2003,47(3):750-752
Sixteen Chilean flamingos, Phoenicopterus chiles, and 10 red-tailed hawks, Buteo jamacensis, were vaccinated in the pectoral muscle with 0.2 ml of a commercially produced killed West Nile virus vaccine intended for use in horses. Half the birds of each species received a booster vaccination 3 weeks after the first injection. Three weeks after the booster vaccination, none of 13 birds surveyed had detectable antibody to West Nile virus. 相似文献
842.
Margaret V. Root DVM PhD Shirley D. Johnston DVM PhD Gary R. Johnston DVM MS Patricia N. Olson DVM PhD 《Veterinary radiology & ultrasound》1996,37(5):363-366
Male (n = 6/group) and female (n = 6/group) kittens were gonadectomized at 7 weeks or 7 months of age, or left intact. At 22 months of age, complete penile extrusion was possible in all of the intact males, in 3/5 (60%) males castrated at 7 months of age, and in none of the males castrated at 7 weeks of age. Antegrade (voiding) cystourethrograms were performed at 22 months of age. Diameter of the preprostatic (p = 0.13) and penile (p>0.25) urethra of male cats did not vary by group. Diameter of the pre-pelvic urethra of female cats gonadectomized at 7 weeks of age was significantly smaller than that of intact females (p = 0.02). 相似文献
843.
844.
J. S. Chapman F. M. Steele D. L. Eggett N. P. Johnston M. L. Dunn 《Cereal Chemistry》2010,87(5):434-438
Degradation of added folic acid and native folates in micronutrient‐fortified corn masa and tortillas was evaluated using masa prepared from either nixtamalized corn flour or fresh nixtamal. Variations in masa pH, masa holding time at an elevated temperature, and iron source failed to show significant differences in folate loss in corn flour masa prepared in the laboratory. Masa was subsequently prepared from fresh nixtamal in a commercial mill in Mexico, and fortified with one of two different micronutrient premixes containing iron, zinc, B‐vitamins, and either unencapsulated or lipid‐encapsulated folic acid. Folate loss in commercial masa increased significantly with prebake masa holding time for both premixes. Unencapsulated folic acid showed a 73% loss after 4 hr of holding, compared to 60% loss for encapsulated. The difference was statistically significant, indicating a protective effect from the lipid coating. No significant differences in folate levels were found between prebake masa and baked tortillas. Holding baked tortillas for up to 12 hr also had no effect on folate levels. Native folate showed no significant losses throughout the process. Results from the commercial tortilla mill indicate that most of the loss in added folic acid occurs during prebake holding of masa, possibly from microbial degradation. 相似文献
845.
Recently, we reported the development of an enzymatic corn wet‐milling process that reduces or eliminates sulfur dioxide requirements during steeping, considerably reduces steep time, and produces starch yields comparable to that of conventional corn wet‐milling. The best results so far, using the enzymatic corn wet‐milling procedure, were achieved when a particular protease enzyme (bromelain) was used. In this study, pasting properties and surface characteristics of starch obtained from six different enzyme treatments (three glycosidases [β‐glucanase, cellulase, and xylanase] and three proteases [pepsin, acid protease, and bromelain]) using the enzymatic corn wet‐milling procedure were evaluated and compared with those from starch obtained using the conventional corn wet‐milling procedure. Significant effects from enzymatic milling were observed on all the three starch pasting properties (peak, shear thinning, and setback). The setback viscosities of starch from all enzyme treatments were significantly lower compared with those of the control sample, indicating that starch polymers from enzymatic corn wet‐milling do not reassociate to the same extent as with the control. Comparison between bromelain treatment and the control sample showed that starch samples obtained from bromelain treatment are very similar to control starch in water‐binding capacity, molecular breakdown, and time to swell when cooked in water. Significant effects from enzymatic milling were observed on the surface characteristics of starch granules. The glycosidase treatments, especially the β‐glucanase samples, showed holes in the starch granules. No visual differences were observed in starch granules between bromelain and control samples. 相似文献