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排序方式: 共有402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.
Profile of Steroid Receptors and Increased Aromatase Immunoexpression in Canine Inflammatory Mammary Cancer as a Potential Therapeutic Target 下载免费PDF全文
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
6.
7.
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
8.
Weber HA Zart MK Hodges AE Molloy HM O'Brien BM Moody LA Clark AP Harris RK Overstreet JD Smith CS 《Journal of agricultural and food chemistry》2003,51(25):7352-7358
The characterization of herbal materials is a significant challenge to analytical chemists. Goldenseal (Hydrastis canadensis L.), which has been chosen for toxicity evaluation by NIEHS, is among the top 15 herbal supplements currently on the market and contains a complex mixture of indigenous components ranging from carbohydrates and amino acids to isoquinoline alkaloids. One key component of herbal supplement production is botanical authentication, which is also recommended prior to initiation of efficacy or toxicological studies. To evaluate material available to consumers, goldenseal root powder was obtained from three commercial suppliers and a strategy was developed for characterization and comparison that included Soxhlet extraction, HPLC, GC-MS, and LC-MS analyses. HPLC was used to determine the weight percentages of the goldenseal alkaloids berberine, hydrastine, and canadine in the various extract residues. Palmatine, an isoquinoline alkaloid native to Coptis spp. and other common goldenseal adulterants, was also quantitated using HPLC. GC-MS was used to identify non-alkaloid constituents in goldenseal root powder, whereas LC-MS was used to identify alkaloid components. After review of the characterization data, it was determined that alkaloid content was the best biomarker for goldenseal. A 20-min ambient extraction method for the determination of alkaloid content was also developed and used to analyze the commercial material. All three lots of purchased material contained goldenseal alkaloids hydrastinine, berberastine, tetrahydroberberastine, canadaline, berberine, hydrastine, and canadine. Material from a single supplier also contained palmatine, coptisine, and jatrorrhizine, thus indicating that the material was not pure goldenseal. Comparative data for three commercial sources of goldenseal root powder are presented. 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.
Emilie Laurin Krishna Thakur Peter G. Mohr Paul Hick Mark St. J. Crane Ian A. Gardner Nicholas J. G. Moody Axel Colling Ingo Ernst 《Journal of fish diseases》2019,42(11):1471-1491
Samples from multiple animals may be pooled and tested to reduce costs of surveillance for infectious agents in aquatic animal populations. The primary advantage of pooling is increased population‐level coverage when prevalence is low (<10%) and the number of tests is fixed, because of increased likelihood of including target analyte from at least one infected animal in a tested pool. Important questions and a priori design considerations need to be addressed. Unfortunately, pooling recommendations in disease‐specific chapters of the 2018 OIE Aquatic Manual are incomplete and, except for amphibian chytrid fungus, are not supported by peer‐reviewed research. A systematic review identified only 12 peer‐reviewed aquatic diagnostic accuracy and surveillance studies using pooled samples. No clear patterns for pooling methods and characteristics were evident across reviewed studies, although most authors agreed there is a negative effect on detection. Therefore, our purpose was to review pooling procedures used in published aquatic infectious disease research, present evidence‐based guidelines, and provide simulated data examples for white spot syndrome virus in shrimp. A decision tree of pooling guidelines was developed for use by peer‐reviewed journals and research institutions for the design, statistical analysis and reporting of comparative accuracy studies of individual and pooled tests for surveillance purposes. 相似文献