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11.
Physiological responses of newborn Bos indicus and Bos indicus x Bos taurus calves after exposure to cold 总被引:1,自引:0,他引:1
R W Godfrey S D Smith M J Guthrie R L Stanko D A Neuendorff R D Randel 《Journal of animal science》1991,69(1):258-263
Brahman (n = 9) and 1/2 Simmental x 1/4 Brahman x 1/4 Hereford (n = 11) calves were utilized to determine the influence of exposure to cold on the physiology of the neonate. All calves were removed from their dams within 20 min of birth and prior to suckling. Calves were assigned randomly within breed to either a warm (W; 31 degrees C) or cold (C; 4 degrees C) environmental treatment group. Jugular blood samples were collected via indwelling catheters at 20-min intervals for 180 min. At 100 to 120 min of sampling, all calves were given 1.2 liters of colostrum from their dams via stomach tube. At 120 min, C calves were placed in the W environment. Calf vigor score (CVS) and rectal temperature were determined at each time blood was collected. Serum or plasma was analyzed for glucose (GLU), lactate (LAC), blood urea nitrogen (BUN), hemoglobin (HEM), triglyceride (TRG), triiodothyronine (T3), thyroxine (T4), insulin (INS), cortisol (CORT) and nonesterified fatty acid (NEFA) concentration. Rectal temperature was lower (P less than .01) in C Brahman than in W Brahman and C or W crossbred calves. Crossbred calves had higher (P less than .01) CVS than Brahman calves. Calves in W had lower (P less than .01) GLU than C calves. Brahman calves had higher GLU, LAC, BUN, TRG, T3, T4 and CORT (P less than .05) than crossbred calves. The C Brahman calves had the highest (P less than .05) TRG, CORT, T3 and T4 of all groups. Concentration of NEFA were higher (P less than .01) in C than in W calves.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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S. Guthrie J. C. Buckland-Wright L. C. Vaughan 《The Journal of small animal practice》1991,32(10):503-508
One normal cadaver specimen and six labrador retrievers with suspected elbow osteochondrosis were examined using a microfocal radiographic technique as an aid to diagnosis. This allowed the production of a magnified image (macro-radiograph) with high spatial resolution. The macroradiographs were compared with radiographs obtained using a standard technique to see if they facilitated decision making with respect to case management. The lesions that were suspected from radiographic examination were correlated with the gross lesions found at elbow arthrotomy. Microfocal radiography gave additional information about the changes within the joints but it still remained difficult to image the lesion satisfactorily in some cases. 相似文献
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Antiproliferative activities of citrus flavonoids against six human cancer cell lines 总被引:14,自引:0,他引:14
Citrus fruits contain high concentrations of several classes of phenols, including numerous hydroxycinnamates, flavonoid glycosides, and polymethoxylated flavones. The latter group of compounds occurs without glycosidic linkages and has been shown to inhibit the proliferation of a number of cancer cell lines. This antiproliferative property was further demonstrated against additional human cancer cell lines, and the antiproliferative actions of a series of synthetic methoxylated flavones were also studied. Similar to the naturally occurring compounds, the synthetic compounds exhibited strong antiproliferative activities. In many cases the IC(50) values occurred below 10 microm. Other hydroxylated flavone and flavanone aglycons also exhibited antiproliferative activities against the cancer cell lines, with the flavones showing greater activities than the flavanones. Glycosylation of these compounds removed their activity. The strong antiproliferative activities of the polymethoxylated flavones suggest that they may have use as anticancer agents in humans. 相似文献
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Erlandson JM Rick TC Braje TJ Casperson M Culleton B Fulfrost B Garcia T Guthrie DA Jew N Kennett DJ Moss ML Reeder L Skinner C Watts J Willis L 《Science (New York, N.Y.)》2011,331(6021):1181-1185
Three archaeological sites on California's Channel Islands show that Paleoindians relied heavily on marine resources. The Paleocoastal sites, dated between ~12,200 and 11,200 years ago, contain numerous stemmed projectile points and crescents associated with a variety of marine and aquatic faunal remains. At site CA-SRI-512 on Santa Rosa Island, Paleocoastal peoples used such tools to capture geese, cormorants, and other birds, along with marine mammals and finfish. At Cardwell Bluffs on San Miguel Island, Paleocoastal peoples collected local chert cobbles, worked them into bifaces and projectile points, and discarded thousands of marine shells. With bifacial technologies similar to those seen in Western Pluvial Lakes Tradition assemblages of western North America, the sites provide evidence for seafaring and island colonization by Paleoindians with a diversified maritime economy. 相似文献
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