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排序方式: 共有592条查询结果,搜索用时 31 毫秒
1.
Jeffrey R. Crass MD Ronald L. Genovese VMD James A. Render DVM Errol M. Bellon MD 《Veterinary radiology & ultrasound》1992,33(4):206-216
Ultrasonography and MRI have become valuable tools for imaging of tendon injuries. The current study examines the histopathologic basis for the imaging abnormalities. Five injured equine forelimbs and two normal contralateral limbs were studied with high resolution real time ultrasound and MRI. Histologic sections were made and correlated with the diagnostic images. All lesions were readily seen by both modalities. Lesions characterized by hemorrhage, edma, and cellular infiltration were sonolucent on ultrasound and bright on MRI images. MRI returned to normal as fibrogenesis ensued. Ultrasound images remained abnormal until fibrillar reallgnment occured with completion of the healing process. High resolution real time ultrasound and MRI both accurately reflect the tissue abnormalities in acute tendon injuries. The injured horse does appear to be an effective model for correlative imaging studies of tendon injuries. 相似文献
2.
George J. Brewer MD William Schall DVM Robert Dick BS Vilma Yuzbasiyan-Gurkan PhD Michael Thomas DVM George Padgett DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(1):41-43
Inherited canine copper toxicosis is a serious problem in Bedlington terriers and West Highland White terriers, and may also be a problem in other less-studied breeds. Affected dogs become ill at midlife with progressive and ultimately fatal liver disease. Treatments for removal of copper and prevention of copper accumulation are available, but are most effective if begun before the dog becomes ill. Until recently diagnosis has not been available until the dog is 1 year of age, and then only by an invasive liver biopsy with determination of liver copper concentration. The authors studied the use of 64copper for early diagnosis of canine copper toxicosis. Two procedures were evaluated. The first involved measuring the concentration of 64copper in blood 24 hours after oral administration of the radioisotope. At this time, 64copper was associated primarily with ceruloplasmin secreted into the blood by the liver. This procedure is useful in the diagnosis of the human counterpart, Wilson's disease. However, the authors found it to be nondiscriminatory between affected and unaffected dogs. In contrast, the second procedure, which involved measuring 64copper excreted in stool during 48 hours after an intravenous dose of radioisotope, yielded results that differentiated most affected and unaffected dogs. 相似文献
3.
Clifford R. Berry DVM Kathy N. Wright DVM Edward B. Breitschwerdt DVM Jerome M. Feldman MD 《Veterinary radiology & ultrasound》1993,34(1):52-55
A 13-year-old neutered female Yorkshire terrier presented with a history of progressive episodic weakness and disorientation of 4 months duration. Physical and neurologic examinations were normal at presentation. Abdominal ultrasound revealed a mass involving the right adrenal gland. Standard planar scintigraphy was performed at 4, 18, and 24 hours after intravenous injection 185 MBq (5mCi) of 123 I-labeled metaiodobenzylguanidine (123 I-MIBG). An area of focal intense uptake was identified in the area of the right adrenal gland. A pheochromocytoma was confirmed histologically after surgical excision. 相似文献
4.
Linda J. Barton DVM Jennifer J. Devey DVM Steven Gorski BSt Louis Mainiero MSt Daniel DeBehnke MD FACEP 《Journal of Veterinary Emergency and Critical Care》1996,6(1):21-28
Ten, anesthetized dogs were instrumented with three pulse oximeter probes; two lingual transmittance probes and one rectal reflective probe. Arterial oxygen desaturation was produced by decreasing the inspired oxygen concentration. Hypotension was produced with an infusion of nitroprusside. Simultaneous pulse oximeter readings (SpO2 ) were compared to co-oximeter measured arterial saturation (SaO2 ) collected over a range of SaO2 (50–100%) and mean arterial pressures (40–100mmHg). Each of the monitors and means of evaluating SpO2 studied provided accurate SpO2 measurements over a range of mean arterial pressure from 40–100mmHg. All of the monitors tested tended to overestimate the SaO2 when the arterial saturation was less than 70%. 相似文献
5.
J K Skeeles M Slavik J N Beasley A H Brown C F Meinecke S Maruca S Welch 《American journal of veterinary research》1980,41(9):1458-1461
Specific-pathogen-free White Leghorn chickens were inoculated with a field strain of infectious bursal disease virus. One group (A) was inoculated at 17 days after the chicks were hatched, and the other groups (C and E) were inoculated at posthatch day 42. Blood samples were obtained for determination of clotting times (whole blood recalcification, prothrombin, and activated partial thromboplastin times), virus-neutralizing antibody, and total hemolytic complement. There were significant increases in clotting times for groups C and E at 3 and 5 days after they were inoculated. There were no significant increases in clotting times at 3 days after inoculation in the group A chickens (inoculated at 17 days after hatching). There were no significant decreases in total complement activity in any of these chickens (groups A, C, and E). This study indicates that the mortality and clinical symptoms observed in chickens experimentally infected with infectious bursal disease virus may be associated with a clotting abnormality because it was noted only in chickens that developed severe clinical disease (inoculated at 42 days after hatching) and was not noted in chickens that remained clinically normal (inoculated at 17 days). 相似文献
6.
Maurice Keith R. Welch Joan M. Brown Christopher P. Latham Roger Earl 《Landscape Ecology》2004,19(6):603-620
The Pocono mesic till barrens (PMTB) are a unique assemblage of fire-maintained shrub communities that support numerous rare species. Historically these barrens covered a large area in the vicinity of Long Pond, Pennsylvania, USA. However, due largely to regional fire suppression instituted in the early 1960s, over 70% of the area covered by barrens succeeded to fire-intolerant forest that does not support the rare species. We investigated the influence of forest proximity on barrens succession across three geomorphic types during periods of high fire frequency and fire suppression, testing the hypothesis that forest processes such as seed rain, shading, and detrital enrichment of soils enhances barrens succession through a contagion effect. Evidence of a forest contagion effect should be shown by increased rates of barrens succession with increasing proximity to the nearest forest edge. In order to detect a forest contagion effect, barrens persistence and barrens succession were modeled in proximity zones of 0-50 m, 50-100 m, 100-200 m, and greater than 200 m from the nearest forest edge. We used existing GIS data layers for fire, geomorphology, and vegetation distribution in 1938, 1963, and 1992. The layers were modified and overlain using ArcView software to determine persistence and succession rates for each unique combination of layers in each proximity zone from 1938 to 1963 (pre-fire suppression) and 1963 to 1992 (post-fire suppression). ANCOVA results indicate that proximity to the nearest forest edge significantly affected barrens persistence rates in both time periods, but succession rates were significantly affected in 1938 to 1963 only. Twenty-eight percent of the 1938 barrens succeeded to forest by 1963; 56% of the 1963 barrens became forest by 1992. Results support previous findings that barrens persistence is enhanced by increased fire frequency, and that barrens persist longer where they overlie flat glacial till than on other geomorphology types. 相似文献
7.
Profile of Steroid Receptors and Increased Aromatase Immunoexpression in Canine Inflammatory Mammary Cancer as a Potential Therapeutic Target
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PJ De Andrés S Cáceres M Clemente MD Pérez‐Alenza JC Illera L Peña 《Reproduction in domestic animals》2016,51(2):269-275
Canine inflammatory mammary cancer (IMC) has been proposed as a model for the study of human inflammatory breast cancer (IBC). The aims of this study were to compare the immunohistochemical expression of aromatase (Arom) and several hormone receptors [estrogen receptor α (ERα), estrogen receptor β (ERβ), progesterone receptor (PR) and androgen receptor (AR)], in 21 IMC cases vs 19 non‐IMC; and to study the possible effect of letrozole on canine IMC and human inflammatory breast cancer (IBC) in vitro using IPC‐366 and SUM‐149 cell lines. Significant elevations of the means of Arom Total Score (TS), ERβ TS and PR TS were found in the IMC group (p = 0.025, p = 0.038 and p = 0.037, respectively). Secondary IMC tumours expressed higher levels of Arom than primary IMC (p = 0.029). Non‐IMC PR‐ tumours contained higher levels of Arom than non‐IMC PR+ tumours (p = 0.007). After the addition of letrozole, the number of IMC and IBC cells dropped drastically. The overexpression of Arom found and the results obtained in vitro further support canine IMC as a model for the study of IBC and future approaches to the treatment of dogs with mammary cancer, and especially IMC, using Arom inhibitors. 相似文献
8.
Water, Air, &; Soil Pollution - A study was conducted to investigate the heavy metal contamination of soil and vegetation in the vicinity of industries around Dhaka city in Bangladesh.... 相似文献
9.
Next to N2 gas, the largest pool of reduced nitrogen in the ocean resides in the enormous reservoir of dissolved organic nitrogen (DON). The chemical identity of most of this material, and the mechanisms by which it is cycled, remain fundamental questions in contemporary oceanography. Amino acid enantiomeric ratios in the high molecular weight fraction of DON from surface and deep water in three ocean basins show substantial enrichment in D enantiomers of four amino acids. The magnitude and pattern of these D/L enrichments indicate that peptidoglycan remnants derived from bacterial cell walls constitute a major source of DON throughout the sea. These observations suggest that structural properties of specific bacterial biopolymers, and the mechanisms for their accumulation, are among the central controls on long-term cycling of dissolved organic nitrogen in the sea. 相似文献
10.
The evidence at present available, although incomplete, gives rise to fears for the future of the edible snail Helix pomatia L. The scale of exploitation is increasing, particularly in Eastern Europe, to meet growing demand, mainly from the West. The growth of legislation to control collecting supports the evidence of declining numbers, but the legislation does not appear to be backed by sufficiently detailed population ecology studies. The need for co-ordinated international action on farming, legislation and ecological study is urged. 相似文献