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11.
Meylan M Eicher R Röthlisberger J Steiner A 《American journal of veterinary research》2002,63(1):78-85
OBJECTIVE: To describe myoelectric activity of the spiral colon in healthy cows. ANIMALS: 7 lactating Simmental X Red-Holstein crossbred cows. PROCEDURE: Cows were implanted with 7 pairs of bipolar silver electrodes (4 in the spiral colon and 1 each in the cecum, distal part of the ileum, and proximal loop of the ascending colon [PLAC]). Myo-electric activity was recorded during 4 days for each cow. Patterns were analyzed, using computer-based methods. RESULTS: Myoelectric activity of the spiral colon was closely associated with motility of the ileum and PLAC and showed the typical organization of migrating myoelectric complexes (MMC). The MMC in the bovine spiral colon (bcMMC) had a mean +/- SD duration of 188.6 +/- 30.8 minutes and was divided into 4 phases. Phases I and II lasted 11.3 +/- 1.4 and 159.4 +/- 33.3 minutes, respectively. Phase III (duration, 5.4 +/- 1.2 minutes) was characterized by 5.2 +/- 0.9 regular spindles (35.4 +/- 5.4 seconds) and 1 final elongated spindle (137.2 +/- 56.4 seconds). Phase III most commonly (73.8 +/- 16.1%) was followed by phase IV (duration, 173 +/- 3.6 minutes). Propagation velocity of phase III was 4.4 +/- 0.5 cm/min, and 13.6% of bcMMC were incompletely propagated through the spiral colon. CONCLUSIONS: Myoelectric activity of the bovine spiral colon is composed of a recurring cyclic pattern similar to MMC of the small intestine. Data of colonic myoelectric activity in healthy cows will serve as a basis for studies on cecal dilatation and dislocation in cattle. 相似文献
12.
Adrian G Mutlow William D Mauch James W Carpenter Todd Smith 《Journal of zoo and wildlife medicine》2006,37(3):381-386
A chimpanzee (Pan troglodytes) with traumatic loss of the distal penis developed a gradually enlarging ventral urethral swelling and progressive dysuria. Endoscopy identified a urethral diverticulum, and endoscopic resection of the diverticulum wall was performed. Postoperative infection caused extensive necrosis of the penis, which necessitated a perineal urethrostomy. Complications of the urethrostomy included urethral obstruction from recurrent urethral stricture. The stricture was managed by regular dilatation using urethral bougies. Because of considerable postoperative swelling, catheterization was required to allow micturition following both the diverticular resection and polyp debulking. A shortened catheter sutured to the skin was tolerated for up to 10 days. Four yr after the urethrostomy, the animal is healthy and asymptomatic with endoscopic examinations performed at 12 mo intervals. This case demonstrates that with appropriate aftercare, perineal urethrostomy is an effective technique in the treatment of chronic distal urethral obstruction in the chimpanzee and probably other primate species. 相似文献
13.
14.
Isabelle Brodard Maher Alsaaod Corinne Gurtner Joerg Jores Adrian Steiner Peter Kuhnert 《Journal of veterinary diagnostic investigation》2021,33(4):801
Digital dermatitis (DD) is a major infectious foot disease of cattle worldwide. Some DD stages are associated with lameness, and the disease has significant economic and animal welfare consequences. The pathogenesis of the disease is not yet fully understood, but Treponema spp. have been associated consistently with clinical cases. Isolation of these fastidious bacteria is difficult and cumbersome. We describe an improved method enabling the culturing of the 3 Treponema spp. (T. pedis, T. phagedenis, and T. medium) from bovine foot specimens derived from DD lesions, using a combination of membrane filtering and subsequent growth on selective agar media. The entire procedure from sampling to verification of individual Treponema spp. takes up to 24 d. In addition, we established a MALDI-TOF MS–based identification method to be applied for confirmation of the different Treponema spp. This scheme provides an unambiguous, simple, and straightforward identification procedure for DD-associated Treponema spp. 相似文献
15.
Adrian Mutlow Ramiro Isaza James W Carpenter David E Koch Robert P Hunter 《Journal of zoo and wildlife medicine》2004,35(4):489-496
Using a crossover study design, the pharmacokinetics of carfentanil and naltrexone after i.v., i.m., and s.c. administration were determined in eight domestic goats (Capra hircus). Serial blood samples were taken up to 120 hr after carfentanil administration, and the plasma drug concentrations were determined using liquid chromatography and mass spectroscopy. All goats were immobilized with 40 microg/kg carfentanil i.m., although the resulting neurologic effects varied considerably. Plasma profiles showed rapid carfentanil absorption and a simple biphasic decline for 12-48 hr. Naltrexone given at 100 mg naltrexone/mg carfentanil 30 min after carfentanil administration produced rapid reversal of immobilization after all routes of administration. Variable fluctuations in the naltrexone plasma concentrations during the first 2.5-3.5 hr were observed, followed by a more consistent biphasic decline. The time to standing was significantly shorter after i.v. compared with s.c. naltrexone, although the time difference (1 min) had little clinical relevance. No statistically significant differences between the naltrexone pharmacokinetic parameters measured for the three routes of naltrexone administration were identified, although the recoveries after i.m. administration were, subjectively, the smoothest. The carfentanil half-life did not differ significantly in the goats given naltrexone by different routes. Although it is currently recommended that the naltrexone dose be divided into s.c. and i.v. portions, this practice does not appear to offer any benefit. 相似文献
16.
Stoffel MH Monnard CW Steiner A Mevissen M Meylan M 《American journal of veterinary research》2006,67(12):1992-1997
OBJECTIVE: To describe the distribution of muscarinic receptor subtypes M(1) to M(5) and interstitial cells of Cajal (ICCs) in the gastrointestinal tract of healthy dairy cows. SAMPLE POPULATION: Full-thickness samples were collected from the fundus, corpus, and pyloric part of the abomasum and from the duodenum, ileum, cecum, proximal loop of the ascending colon, and both external loops of the spiral colon of 5 healthy dairy cows after slaughter. PROCEDURES: Samples were fixed in paraformaldehyde and embedded in paraffin. Muscarinic receptor subtypes and ICCs were identified by immunohistochemical analysis. RESULTS: Staining for M(1) receptors was found in the submucosal plexus and myenteric plexus. Antibodies against M(2) receptors stained nuclei of smooth muscle cells only. Evidence of M(3) receptors was found in the lamina propria, in intramuscular neuronal terminals, on intermuscular nerve fibers, and on myocytes of microvessels. There was no staining for M(4) receptors. Staining for M(5) receptors was evident in the myocytes of microvessels and in smooth muscle cells. The ICCs were detected in the myenteric plexus and within smooth muscle layers. Distribution among locations of the bovine gastrointestinal tract did not differ for muscarinic receptor subtypes or ICCs. CONCLUSIONS AND CLINICAL RELEVANCE: The broad distribution of M(1), M(3), M(5), and ICCs in the bovine gastrointestinal tract indicated that these components are likely to play an important role in the regulation of gastrointestinal tract motility in healthy dairy cows. Muscarinic receptors and ICCs may be implicated in the pathogenesis of motility disorders, such as abomasal displacement and cecal dilatation-dislocation. 相似文献
17.
Computed Tomographic Angiography under Sedation in the Diagnosis of Suspected Canine Pancreatitis: A Pilot Study
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A.M. Adrian D.C. Twedt S.L. Kraft A.J. Marolf 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(1):97-103
Background
Computed tomography (CT) is highly accurate for diagnosing pancreatitis in humans. The diagnosis of pancreatitis in dogs is based on clinical signs, laboratory findings, and ultrasonographic (US) changes. There are, however, inherent limitations in relying on laboratory and ultrasound findings for the clinical diagnosis of pancreatitis in dogs.Hypothesis/Objectives
We hypothesized that CT angiography would be a rapid and reliable method to confirm pancreatitis in dogs compared to ultrasonography. The aim was to describe the CT characteristics and compare them to ultrasound findings and correlate the CT appearance to the severity of the patients'' clinical course.Animals
A prospective pilot case series; 10 dogs with pancreatitis were enrolled if the history, clinical signs, laboratory, and ultrasonographic findings were indicative of pancreatitis.Methods
A 3‐phase angiographic CT was performed under sedation. Afterward, each dog had US‐guided aspirates of the pancreas collected and blood drawn for cPLi assay. Images were evaluated for portion of visible pancreas, pancreatic size and margin, pancreatic parenchyma, presence of peripancreatic changes and contrast enhancement pattern. The results were compared with outcome.Results
An enlarged, homogeneously to heterogeneously attenuating and contrast‐enhancing pancreas with ill‐defined borders was identified in all dogs. CT identified more features characterizing pancreatic abnormalities compared to US. Thrombi were found in 3/10 dogs. Three dogs with heterogeneous contrast enhancement had an overall poorer outcome than those with homogenous enhancement.Conclusions and Clinical Importance
CT angiography under sedation was used in dogs to confirm clinically suspected pancreatitis and identified clinically relevant and potentially prognostic features of pancreatitis in dogs. 相似文献18.
Urszula Paslawska Agnieszka Noszczyk-Nowak Robert Paslawski Adrian Janiszewski Liliana Kiczak Dorota Zysko Jozef Nicpon Ewa A Jankowska Andrzej Szuba Piotr Ponikowski 《Acta veterinaria Scandinavica》2014,56(1)
Background
Swine are recognized animal models of human cardiovascular diseases. Normal values of cardiac morphology and function have been published for swine but for smaller number of pigs and not for swine whose weights ranged up 100 kg. In order to improve the value of results of an investigation on cardiac morphology and function in swine when such data are extrapolated to humans, the aim of this study was to document electrocardiographic and echocardiographic measures of cardiac morphology and function in swine. The study comprised 170 single and repeated measurements that were made in 132 healthy domestic swine (Sus domesticus) whose weights ranged between 20-160 kg and were used as controls in three different experiments. All electrocardiographic and echocardiographic measurements in all swine were done under general anaesthesia.Results
Statistically significant correlations were found between body weight and heart rate (HR), the duration of the P-wave, the duration of the QRS interval, the duration of the QT interval, and the corrected QT ratio (QTc). Since body weight was positively correlated with age, statistically significant correlations were also found between age and HR, the duration of the P-wave, the duration of the QRS interval, the duration of the QT interval, and the QTc. We found that the thickness of the left ventricular wall and the internal diameter of the left ventricle increased with age and body weight. We also found positive trends between body weight and ejection fraction and body weight and fractional shortening. We also found a positive relationship between age, body weight, and the ratio of the left ventricular internal diameter to its wall thickness, as well as the relative left atrial size.Conclusion
Many electro- and echocardiographic measures of cardiac morphology and function of healthy swine are related to their body weight. When the electro- and echocardiographic measures of domestic swine and humans are compared, the most comparable electrocardiographic values are those that were determined in swine whose body weights are not greater than 70 kg. In contrast, the most comparable echocardiographic measures are those that were determined in swine with a body weight of 40–110 kg. 相似文献19.
Michel JB Shen YK Aiden AP Veres A Gray MK;Google Books Team Pickett JP Hoiberg D Clancy D Norvig P Orwant J Pinker S Nowak MA Aiden EL 《Science (New York, N.Y.)》2011,331(6014):176-182
We constructed a corpus of digitized texts containing about 4% of all books ever printed. Analysis of this corpus enables us to investigate cultural trends quantitatively. We survey the vast terrain of 'culturomics,' focusing on linguistic and cultural phenomena that were reflected in the English language between 1800 and 2000. We show how this approach can provide insights about fields as diverse as lexicography, the evolution of grammar, collective memory, the adoption of technology, the pursuit of fame, censorship, and historical epidemiology. Culturomics extends the boundaries of rigorous quantitative inquiry to a wide array of new phenomena spanning the social sciences and the humanities. 相似文献
20.
Growth, survival, stem characteristics, resistance to wind, and canker disease of 51 poplar clones were evaluated at age 9 and 10 years, and compared to measurements at age 3 in two trials on the Lower Valley of the Colorado River, Argentina. About 30% of the clones in both trials had large changes in growth rankings at age 9 and 10 compared to rankings at age 3. Canker incidence increased about 4-fold between age 3, and measurements at age 9 and 10. Stem form was in general satisfactory, and wind incidence was almost nil. In trial 1, clones 588–1, Conti 12, 582–41, and 582–5 occupied the upper positions in the growth rankings at age 3 and 10, and the clone 588–1 ranked first both in growth and canker incidence in 1998. Stem growth trajectories of clones with similar growth rates did not differ among clones with, and without canker disease. In trial 2, the range in growth among clones was narrower than in trial 1, and canker disease, although of minor incidence, was present in most clones at age 9. Some of the P. deltoides clones in the trials had similar growth, and less canker disease than the Euroamerican clones commonly grown in the region, but progressive canker incidence should be addressed with additional selection trials. 相似文献