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91.
Clifford R. Berry DVM John K. House DVM Paul P. Poulos DVM PhD John E. Madigan DVM MS J. Carroll Woodard DVM PhD Roy R. Pool DVM PhD Timothy R. O'Brien DVM PhD Norman Ackerman DVM 《Veterinary radiology & ultrasound》1994,35(5):355-361
The radiographic and pathologic findings of two Peruvian Paso foals with osteopetrosis are described. Both foals, one male and one female, presented with respiratory difficulty, brachygnathia and failure to rise after birth. Both foals were mildly anemic, hypogammaglobulinemic and had elevations in serum alkaline phosphatase. Increased medullary bone opacity was noted on radiographs of the extremities, spine and skull in both foals. A lack of normal cortical:medullary bone distinction was evident radiographically. The medullary primary spongiosa appeared to run in parallel columns away from the physes of all long bones and the vertebrae. This created a distinctive hour glass appearance to the osteopetrotic bones. One foal developed a bacterial pneumonia. Both foals were euthanized due to failure to thrive. Histopathology and electron microscopy documented these foals to have normal osteoclastic numbers but lack normal ruffled borders, lack of a clear zone and normal lysosomal numbers indicative of cellular dysfunction. These clinical, radiographic and pathologic findings are similar to the juvenile, lethal autosomal recessive form of osteopetrosis described in humans. Osteopetrosis has not been previously described in a female foal. 相似文献
92.
Campylobacter jejuni infection in the ferret: an animal model of human campylobacteriosis 总被引:7,自引:0,他引:7
J G Fox J I Ackerman N Taylor M Claps J C Murphy 《American journal of veterinary research》1987,48(1):85-90
Campylobacter infection in weanling ferrets (Mustela putorius furo) was studied as an animal model for enteric campylobacteriosis in persons. The screening of fecal cultures on selective campylobacter media showed that Campylobacter jejuni/coli was not present in the normal enteric flora. Intragastric feeding of a mixture of cat feed and 2.5 X 10(8) C jejuni isolated from ferrets with naturally occurring proliferative colitis was accomplished. All ferrets (n = 8) became infected on 3 days after they were inoculated, and at 5 to 7 days, they had bile-tinged, liquid feces with excessive mucus and blood. Ferrets gradually recovered from the diarrhea, and feces were normal 10 to 14 days after inoculation was done. Feces contained C jejuni at 14, 23, 28, 39, 46, 60, 91, 101, 109 and 144 days. In the second experiment, weanling ferrets initially were treated with 10% sodium bicarbonate, and 1 X 10(10) C jejuni organisms were administered in the cat feed. Diarrhea with fecal leukocytes and occult blood with occasional mucus appeared in almost all of the 21 ferrets from days 4 through 7. Campylobacter jejuni was isolated from the blood of 11 ferrets between 3 hours and 14 days after they were inoculated. Campylobacter jejuni bactericidal antibodies were present in serum samples at 14 days, with titers of 1:16 to 1:32. Intestinal lesions including cellular infiltration with mononuclear and polymorphonuclear leukocytes were in the lamina propria of the pyloric mucosa and small intestine of infected and control ferrets. The colon of 3 infected ferrets had small focal infiltrates of neutrophils on the lamina propria; one ferret had perivascular cuffing.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
93.
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95.
J D Pettinati S A Ackerman R K Jenkins M L Happich J G Phillips 《Journal of the Association of Official Analytical Chemists》1983,66(3):759-765
Analyses of meat samples after preparation with either a bowl cutter or by the official procedure with a food chopper were compared for homogeneity of comminution and for differences in fat, moisture, and protein content. Cutting time in the bowl cutter was limited to minimize temperature rise in samples. Beef chuck, pork shoulder, and beef shank, cheek, and tongue were used in the study. Variances of replicate analysis data for the 5 meat types were pooled for either cutter or chopper treatment and for each analyzed component. Sample portions cut and mixed by using the bowl cutter were more homogeneous than those ground with a food chopper. Comparative accuracy was indicated by fat and moisture means: 5 were in good agreement and 5 differed significantly; 3 of 5 paired protein means differed significantly but were within 0.3% protein. Results on precision and accuracy as well as the simplicity and convenience of the bowl cutter procedure favor its use as an alternative to a food chopper for preparing meat samples for analysis. 相似文献
96.
Ge X d'Avignon DA Ackerman JJ Collavo A Sattin M Ostrander EL Hall EL Sammons RD Preston C 《Journal of agricultural and food chemistry》2012,60(5):1243-1250
Lolium spp., ryegrass, variants from Australia, Brazil, Chile, and Italy showing differing levels of glyphosate resistance were examined by (31)P NMR. Extents of glyphosate (i) resistance (LD(50)), (ii) inhibition of 5-enopyruvyl-shikimate-3-phosphate synthase (EPSPS) activity (IC(50)), and (iii) translocation were quantified for glyphosate-resistant (GR) and glyphosate-sensitive (GS) Lolium multiflorum Lam. variants from Chile and Brazil. For comparison, LD(50) and IC(50) data for Lolium rigidum Gaudin variants from Italy were also analyzed. All variants showed similar cellular uptake of glyphosate by (31)P NMR. All GR variants showed glyphosate sequestration within the cell vacuole, whereas there was minimal or no vacuole sequestration in the GS variants. The extent of vacuole sequestration correlated qualitatively with the level of resistance. Previous (31)P NMR studies of horseweed ( Conyza canadensis (L.) Cronquist) revealed that glyphosate sequestration imparted glyphosate resistance. Data presented herein suggest that glyphosate vacuolar sequestration is strongly contributing, if not the major contributing, resistance mechanism in ryegrass as well. 相似文献
97.
From the early 2000s there has been a general shift in South Africa in harvesting and extraction systems from the use of semi- to fully-mechanised systems. Any increase in mechanisation, as is occurring in Zululand, will need to take into consideration damage to stumps and the subsequent ability to regenerate by coppice. In 2002, four types of harvesting and extraction systems, arranged in a randomised complete block design, were used to clearfell a stand of E. grandis × E. urophylla. A motor-manual harvesting system was used to carry out the manual harvesting system (Man). The fully mechanised system (Mech) consisted of a single-grip harvesting head used with a tracked excavator to carry out all felling and processing operations. Two additional systems (Man_Mech_3W and Man_Mech_Flexi) had increased levels of mechanisation over that of the Man treatment. Both these harvesting systems made use of a Bell debarker, with loading carried out by a Bell three-wheeled loader in the Man_Mech_3W, and by a Flexiloader in the Man_Mech_Flexi treatments. Data collected from these four treatments were used to determine the effects of mechanised harvesting systems on type and severity of stump damage, coppicing potential and coppice growth over the rotation. Irrespective of harvesting system, more damage occurred to the top than bottom half of the stump, with a significant decrease in coppice regrowth with increasing stump damage. Most damage and least coppice regrowth occurred in the extraction rows where the damage recorded could be attributed to vehicle movement, tear-outs and/or log stripping. There was no significant difference between the harvesting systems in terms of stump mortality, final stem stocking and rotation-end volume. Thus, individual components within each harvesting system can have a larger impact than the overall harvesting system used. Future research should focus on these components, and where associated damage occurs for a specific component, this should be lessened through management intervention, training or technological improvements. 相似文献
98.
Xia Ge D André d'Avignon Joseph JH Ackerman R Douglas Sammons 《Pest management science》2010,66(4):345-348
BACKGROUND: Glyphosate‐resistant (GR) weed species are now found with increasing frequency and threaten the critically important GR weed management system. RESULTS: The reported 31P NMR experiments on glyphosate‐sensitive (S) and glyphosate‐resistant (R) horseweed, Conyza canadensis (L.) Cronq., show significantly more accumulation of glyphosate within the R biotype vacuole. CONCLUSIONS: Selective sequestration of glyphosate into the vacuole confers the observed horseweed resistance to glyphosate. This observation represents the first clear evidence for the glyphosate resistance mechanism in C. canadensis. Copyright © 2010 Society of Chemical Industry 相似文献
99.
Subpolar North Atlantic proxy records document millennial-scale climate variations 500,000 to 340,000 years ago. The cycles have an approximately constant pacing that is similar to that documented for the last glacial cycle. These findings suggest that such climate variations are inherent to the late Pleistocene, regardless of glacial state. Sea surface temperature during the warm peak of Marine Isotope Stage 11 (MIS 11) varied by 0.5 degrees to 1 degrees C, less than the 4 degrees to 4.5 degrees C estimated during times of ice growth and the 3 degrees C estimated for glacial maxima. Coherent deep ocean circulation changes were associated with glacial oscillations in sea surface temperature. 相似文献
100.
Magnetic Field and Plasma Observations at Mars: Initial Results of the Mars Global Surveyor Mission 总被引:2,自引:0,他引:2
MH Acu?a JEP Connerney P Wasilewski RP Lin KA Anderson CW Carlson J McFadden DW Curtis D Mitchell H Reme C Mazelle JA Sauvaud C d'Uston A Cros JL Medale SJ Bauer P Cloutier M Mayhew D Winterhalter NF Ness 《Science (New York, N.Y.)》1998,279(5357):1676-1680
The magnetometer and electron reflectometer investigation (MAG/ER) on the Mars Global Surveyor spacecraft has obtained magnetic field and plasma observations throughout the near-Mars environment, from beyond the influence of Mars to just above the surface (at an altitude of approximately 100 kilometers). The solar wind interaction with Mars is in many ways similar to that at Venus and at an active comet, that is, primarily an ionospheric-atmospheric interaction. No significant planetary magnetic field of global scale has been detected to date (<2 x 10(21) Gauss-cubic centimeter), but here the discovery of multiple magnetic anomalies of small spatial scale in the crust of Mars is reported. 相似文献