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排序方式: 共有252条查询结果,搜索用时 15 毫秒
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Wing SL Harrington GJ Smith FA Bloch JI Boyer DM Freeman KH 《Science (New York, N.Y.)》2005,310(5750):993-996
Rapid global warming of 5 degrees to 10 degrees C during the Paleocene-Eocene Thermal Maximum (PETM) coincided with major turnover in vertebrate faunas, but previous studies have found little floral change. Plant fossils discovered in Wyoming, United States, show that PETM floras were a mixture of native and migrant lineages and that plant range shifts were large and rapid (occurring within 10,000 years). Floral composition and leaf shape and size suggest that climate warmed by approximately 5 degrees C during the PETM and that precipitation was low early in the event and increased later. Floral response to warming and/or increased atmospheric CO2 during the PETM was comparable in rate and magnitude to that seen in postglacial floras and to the predicted effects of anthropogenic carbon release and climate change on future vegetation. 相似文献
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Charles O Thoen Jerald L Jarnagin Charles C Muscoplat L.S Cram Donald W Johnson Rube Harrington 《Comparative immunology, microbiology and infectious diseases》1980,3(3):355-361
A comparison of in vitro lymphocyte responses and delayed type tuberculin skin test responses was made in an animal experimentally exposed to a Mycobacterium bovis-infected animal and in cattle naturally infected with M. bovis. Tuberculin skin tests did not suppress in vitro lymphocyte responses to M. bovis PPD and to M. avium PPD tuberculin. The whole blood test used in these studies provided for considerable savings in time as compared to use of purified lymphocytes for evaluating in vitro cellular responses. Variations in the responsiveness of lymphocytes to specific mycobacterial antigens was observed, therefore, it is recommended that profiles be established using three or more tests conducted at 14-day intervals. 相似文献
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Michael R. Metcalf DVM MS Louis C. Sellett MS James E. Smallwood DVM MS Donald E. Thrall DVM PhD Ben D. Harrington DVM 《Veterinary radiology & ultrasound》1989,30(3):111-118
Both foredigits and metacarpophalangeal joints of six Quarter Horse foals were scanned serially to six months of age using 99 Tc-methylene diphosphonate. Dorsal scans were made on day 1 and at two, four, six, ten, 14, 18, 22 and 26 weeks of age. Scans were assessed visually for distal third metacarpal, proximal phalangeal, and middle phalangeal physeal appearance and closure. Scans were also evaluated by computer region-of-interest (ROI) and line-profile analysis to characterize the physes quantitatively. Physeal region radioactivity relative to a disphyseal reference region was greatest at four weeks for all physes. Scintigraphic physeal closure of all physes occurred at approximately six months of age with a range of four and one half to greater than six months. The study was conducted to allow better assessment of diffuse and focal physeal disease by determining developmental times at which normal physeal region radioactivity has decreased enough to not obscure abnormal radioactivity and by quantifying scintigraphic physeal appearance which enables computer analysis to detect visually indeterminate physeal abnormalities. 相似文献
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Case JB MacPhail CM Withrow SJ 《Journal of the American Animal Hospital Association》2012,48(4):245-249
Intermuscular lipomas (IML) in dogs can be associated with ominous clinical signs, especially in the thoracic limb. However, the prognosis is excellent following surgical excision. There is a paucity of information in the veterinary literature regarding IML. Our objective was to describe the anatomical location, imaging techniques, and clinical findings in a series of dogs that were diagnosed and treated for IML. The prevalence of thoracic versus pelvic limb IML was not different. Most IML of the thoracic limb were located in the axilla. Operative time for IML of the thoracic and pelvic limb averaged 60 minutes. Complications were rare after marginal surgical excision and recurrence was not seen in any of the cases in this report. Intermuscular lipomas of the axilla are as common as IML of the caudal thigh. Surgical treatment of both axillary and caudal-thigh IML is associated with an excellent prognosis in dogs. 相似文献
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