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排序方式: 共有257条查询结果,搜索用时 445 毫秒
31.
Thorsten Rick Miriam Kleiter Ilse Schwendenwein Eberhard Ludewig Martin Reifinger Katharina M. Hittmair 《Veterinary radiology & ultrasound》2019,60(1):56-64
Contrast‐enhanced ultrasonography (CEUS) is increasingly available for veterinary patients, however limited studies describe the use of this method for characterizing intrathoracic mass lesions. The aim of this prospective, observational study was to describe CEUS enhancement patterns for intrathoracic mass lesions in a sample of cats and dogs. Sixty patients (36 dogs, 24 cats) were included. Standardized CEUS examinations were performed for 41 pulmonary masses (68%) and 19 mediastinal masses (32%). Final diagnosis was based on cytology and/or histopathology. Absolute time to enhancement (TTE) values were recorded for the intrathoracic mass lesions and spleen. The spleen was used as a reference parenchymal organ to calculate relative TTE (rTTE) values. Absolute TTE of the spleen and intrathoracic mass lesions differed for dogs and cats (P = 0.001). The rTTE values significantly differed between lesions of neoplastic versus non‐neoplastic origin (P = 0.004). The majority of neoplastic pulmonary masses were supplied by bronchial arteries (63%), while most nonneoplastic pulmonary masses were supplied by pulmonary arteries (78%). The sensitivity and specificity for detecting pulmonary neoplastic masses with rTTE were 63% and 78%, respectively. Enhancement patterns for mediastinal thymomas and lymphomas significantly differed (P = 0.002). Thymomas enhanced heterogeneously in a centripetal pattern (86%), whereas lymphomas typically enhanced uniformly in a centrifugal pattern (75%). Findings indicated that CEUS is a feasible method for characterizing intrathoracic mass lesions in dogs and cats, however, the diagnostic sensitivity for detecting neoplastic pulmonary masses was low. 相似文献
32.
A 2-month-old, male alpaca had a 1-month history of mucoid ocular discharge from the left eye. Signalment, history and clinical findings were suggestive of a congenital nasolacrimal outflow obstruction. A dacryocystorhinogram confirmed bilateral nasolacrimal duct atresia, which involved the distal half of both nasolacrimal ducts. In order to establish alternative outflow, a conjunctivomaxillosinusotomy and conjunctivorhinostomy were performed on the right and left eye, respectively. The surgical openings remain patent after 11 months, and there have been no clinical signs of nasolacrimal disease. 相似文献
33.
ObjectiveTo examine the relationship between body mass and thoracic dimensions on arterial oxygen tensions (PaO2) in anaesthetized horses and ponies positioned in dorsal recumbency.Study designProspective clinical study.AnimalsThirty six client-owned horses and ponies, mean [±SD (range)] age 8.1 ± 4.8 (1.5–20) years and mean body mass 467 ± 115 (203–656) kg.MethodsBefore general anaesthesia, food and water were withheld for 12 and 1 hours respectively. Body mass (kg), height at the withers (H), thoracic circumference (C), thoracic depth (length between dorsal spinous process and sternum; D), thoracic width (between point of shoulders; W), and thoracic diagonal length (point of shoulder to last rib; L) were measured. Pre-anaesthetic medication was with intravenous (IV) romifidine (0.1 mg kg−1). Anaesthesia was induced with an IV ketamine (2.2 mg kg−1) and diazepam (0.05 mg kg−1) combination and maintained with halothane in 1:1 oxygen:nitrous oxide (N2O) mixture. Animals were positioned in dorsal recumbency and allowed to breathe spontaneously. Nitrous oxide was discontinued after 10 minutes, and arterial blood samples obtained and analysed for gas tensions at 15, 30 and 60 minutes after connection to the anaesthetic breathing circuit. Data were analysed using anova and Pearson's correlation co-efficient.ResultsThe height per unit body mass (H kg−1) and thoracic circumference per unit body mass (C kg−1) correlated strongly (r = 0.85, p < 0.001 and r = 0.82, p < 0.001 respectively) with arterial oxygen tensions (PaO2) at 15 minutes.ConclusionsThere is a strong positive correlation between H kg−1 and C kg−1 and PaO2 after 15 minutes of anaesthesia in halothane-anaesthetized horses positioned in dorsal recumbency.Clinical relevanceReadily obtained linear measurements (height and thoracic circumference) and body mass may be used to predict the ability of horses to oxygenate during anaesthesia. 相似文献
34.
An 11-year-old Thoroughbred mare was diagnosed with sialolithiasis of the right parotid salivary duct. A firm nonpainful subcutaneous mass was palpable in the right maxillary region adjacent to premolar 4 (tooth 108). Radiographic and ultrasonographic examinations identified a discrete mineralised ovoid mass that was hyperechoic and produced an acoustic shadow. Surgical excision of the mass was performed under standing sedation using a transcutaneous approach and the excised sialolith submitted for histopathological and mineral composition analyses. Histological examination found no evidence of a nidus at the sialolith's core. Mineral analysis of the sialolith revealed its composition to be 40% calcium phosphate (apatite) and 60% calcium carbonate. The mare recovered with no post-operative complications and was clinically unremarkable 2 years later. 相似文献
35.
用黑色管道进行环流熏蒸的杀虫试验 总被引:2,自引:2,他引:0
根据气流理论,用仓外与粮堆相通的黑色管道构成循环系统,利用昼夜温差形成慢速环流气流,加速PH3气体在粮堆内的扩散和渗透,达到了较好的杀虫效果。 相似文献
36.
Valerie M. Sadler DVM Erik R. Wisner DVM James T. Robertson DVM Valentine S. Moses DVM 《Veterinary radiology & ultrasound》1999,40(3):259-261
Congenital anomalies of the equine salivary glands and their ductal systems are rare. In man, parotid duct atresia is thought to be due to a congenital malformation of the first branchial arch. One horse with unilateral parotid salivary duct atresia is described. Imaging modalities available for accurate diagnosis, and treatment options, are reviewed. 相似文献
37.
大多数雷诺平均湍流模型(RANS)基于线性和各项同性假设求解雷诺应力(Reynolds stress),因此对高压力梯度区、大曲率回流以及复杂的分离流动的预测误差较大.在近壁区较少网格的条件下,部分时均(PANS)方法被认为比大涡模拟(LES)获得结果更好.通过RNG k-ε湍流模型构造部分时均化模型,引入雷诺应力的非线性求解方法,提出了一种新的非线性PANS模型,并应用该非线性PANS模型分别对绕NACA0015水翼翼型流场和90°长方形截面弯管内流场进行了流动的数值模拟.结果表明:非线性PANS模型的数值结果与试验数据吻合较好,其在高压力梯度区的预测准确性高,并能准确预测流动分离诱发的三维非线性流动,证明了该方法捕捉高压力梯度、大曲率流动的有效性.该计算方法可以用来预测透平机械内部复杂的涡结构. 相似文献
38.
Andrea Steinmetz Lena Locher† Uta Delling‡ Jean-Claude Ionita‡ Eberhard Ludewig Gerhard Oechtering Thomas Wittek† 《Veterinary ophthalmology》2009,12(4):259-262
The ophthalmologic, radiologic and surgical findings of a 2-year-old Scottish Highland Cattle heifer with a dermoid cyst within the bony part of the nasolacrimal duct and the successful treatment are presented. 相似文献
39.
Marion Florin Elina Rusanen† Michael Haessig‡ Marianne Richter Bernhard M. Spiess 《Veterinary ophthalmology》2009,12(6):350-356
Objective To document the clinical presentation, diagnostics, treatment, and clinical outcome of rabbits with dacryocystitis.
Materials and methods This retrospective study included 28 rabbits diagnosed with dacryocystitis. Available records of clinical and ophthalmological examinations, bacteriological samplings, diagnostic imaging, and treatment were reviewed. A telephone survey of the owners was conducted to evaluate recovery and recurrences.
Results The mean age of the 28 rabbits presenting with ocular discharge from the nasolacrimal duct was 4.4 years. In 25 rabbits (89%), dacryocystitis was a unilateral finding. No underlying cause could be determined in 10 animals (35%). Dental malocclusion was observed in 14 rabbits (50%) and rhinitis in two animals (7%), with one animal showing both symptoms (4%). One rabbit (4%) presented with panophthalmitis. Most animals (96%) received topical antibiotic treatment. If necessary, additional topical (acetylcysteine, vitamin A ointment, nonsteroidals) or systemic treatment (antibiotics, nonsteroidals, paramunity inducer, and glucocorticoids) was provided. The mean duration of therapy was 5.8 weeks. The nasolacrimal duct was flushed in 27 of 31 affected eyes (87%). Dentistry was performed in 80% of the animals suffering from malocclusion. Regarding the clinical outcome, 12 animals (43%) showed complete recovery, eight rabbits (28%) were euthanized, three (11%) died due to unrelated causes, and three (11%) were lost to follow-up. Two rabbits (7%) continue to display signs of dacryocystitis and are being treated symptomatically by the owners.
Conclusions This study reports the clinical presentation, treatment, and outcome of dacryocystitis in rabbits and outlines the importance of examination of the oral cavity, diagnostic imaging, and bacteriologic sampling. 相似文献
Materials and methods This retrospective study included 28 rabbits diagnosed with dacryocystitis. Available records of clinical and ophthalmological examinations, bacteriological samplings, diagnostic imaging, and treatment were reviewed. A telephone survey of the owners was conducted to evaluate recovery and recurrences.
Results The mean age of the 28 rabbits presenting with ocular discharge from the nasolacrimal duct was 4.4 years. In 25 rabbits (89%), dacryocystitis was a unilateral finding. No underlying cause could be determined in 10 animals (35%). Dental malocclusion was observed in 14 rabbits (50%) and rhinitis in two animals (7%), with one animal showing both symptoms (4%). One rabbit (4%) presented with panophthalmitis. Most animals (96%) received topical antibiotic treatment. If necessary, additional topical (acetylcysteine, vitamin A ointment, nonsteroidals) or systemic treatment (antibiotics, nonsteroidals, paramunity inducer, and glucocorticoids) was provided. The mean duration of therapy was 5.8 weeks. The nasolacrimal duct was flushed in 27 of 31 affected eyes (87%). Dentistry was performed in 80% of the animals suffering from malocclusion. Regarding the clinical outcome, 12 animals (43%) showed complete recovery, eight rabbits (28%) were euthanized, three (11%) died due to unrelated causes, and three (11%) were lost to follow-up. Two rabbits (7%) continue to display signs of dacryocystitis and are being treated symptomatically by the owners.
Conclusions This study reports the clinical presentation, treatment, and outcome of dacryocystitis in rabbits and outlines the importance of examination of the oral cavity, diagnostic imaging, and bacteriologic sampling. 相似文献
40.