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981.
J. Kirpensteijn R.J. Maarschalkerweerd I. van der Gaag H.S. Kooistra F.J. van Sluijs 《The Veterinary quarterly》2013,33(2):67-70
Summary The macroscopic and histological appearance of jejunal antimesenteric incisions approximated with two different absorbable suture materials (monofilament versus multifilament) and three closure techniques (appositional single layer, crushing single layer, and double layer) were compared in healthy dogs at 14 or 28 days, postoperatively. No significant differences between the two suture materials were observed for most of the macroscopic or histological variables. However, the monofilament suture material caused significantly more fibrous tissue reaction in the muscular layer of the jejunum than did the multifilament suture material. Of the three enterotomy closure techniques used in this study, the appositional single‐layer method proved to be the best. The double‐layer closure method caused a significant decrease in the incisional circumference, the relative circumference, and volume of the jejunum, and a significant increase in jejunal wall thickness. Our findings suggest that canine jejunal enterotomy incisions can be closed using an appositional suture pattern with relatively rapidly absorbable monofilament suture material. The use of double‐layer suture patterns for closure of jejunal enterotomy incisions should be avoided because the size of the intestinal lumen may be reduced. 相似文献
982.
J. Thuróczy F.J. van Sluijs H.S. Kooistra G. Voorhout J.A. Mol J.S. van der Linde‐Sipman 《The Veterinary quarterly》2013,33(2):56-61
Summary In a 10‐year‐old ovariohysterectomized standard Schnauzer, the finding of dexamethasone‐resistant hypersecretion of cortisol, the results of computed tomography, and elevated plasma concentrations of ACTH suggested the presence of both adrenocortical tumour and pituitary‐dependent hyperadrenocorticism. The dog made an uneventful recovery after bilateral adrenalectomy and remained in good health for 31/2 years with substitution for the induced hypoadrenocorticism. Then the enlarged pituitary caused neurological signs and eventually euthanasia was performed. The surgically excised right adrenal contained a well‐circumscribed tumour of differentiated adrenocortical tissue and in the left adrenal there were two adrenocortical tumours and a pheochromocytoma. The unaffected parts of the adrenal cortices were well developed and without regressive transformation. At necropsy there were no metastatic lesions. The cells of the pituitary tumour were immunopositive for ACTH and had characteristics of malignancy. The present combination of corticotrophic tumour, adrenocortical tumours, and pheochromocytoma may be called ‘multiple endocrine neoplasia’ (MEN), but does not correspond to the inherited combinations of diseases known in humans as the MEN‐1 and the MEN‐2 syndromes. It is suggested that the co‐existence of hyperadrenocorticism and pheochromocytoma may be related to the vascular supply of the adrenals. Some chromaffin cells of the adrenal medulla are directly exposed to cortical venous blood, and intra‐adrenal cortisol is known to stimulate catecholamine synthesis and may promote adrenal medullary hyperplasia or neoplasia. 相似文献
983.
L. Vervelde M.G.R. Matthijs D.A. van Haarlem J.J. de Wit C.A. Jansen 《Veterinary immunology and immunopathology》2013,151(3-4):337-341
Natural killer (NK) cells are cytotoxic lymphocytes and play an important role in the early defence against viruses. In this study we focussed on NK cell and interferon (IFN) responses after infection with infectious bronchitis virus (IBV). Based on surface expression of CD107+, enhanced activation of lung NK cells was observed at 1 dpi, whereas in blood prolonged NK-cell activation was found. IFN-α and IFN-β mRNA and proteins were not rapidly induced whereas IFN-γ production in lung, measured by Elispot assay, increased over time at 2 and 4 dpi. In contrast, IFN-γ production in blood was highest at 1 dpi and decreased over time down to levels comparable to uninfected birds at 4 dpi. Collectively, infection with IBV-M41 resulted in activation of NK cells in the lung and blood and rapid production of IFN-γ and not IFN-α and IFN-β compared to uninfected birds. 相似文献
984.
M. PLOEG V. SAEY C. M. de BRUIJN A. GRÖNE K. CHIERS G. van LOON R. DUCATELLE P. R. van WEEREN W. BACK C. DELESALLE 《Equine veterinary journal》2013,45(1):101-106
Reasons for performing study: In horses, aortic sinus of Valsalva aneurysms or tears in the aortic root are well‐recognised conditions in breeding stallions, often leading to sudden death. A more uncommon form of aortic rupture, located proximal to the ligamentum arteriosum has been reported in 3 Friesian horses. Objectives: The purpose of this study was to phenotypically characterise aortic rupture and aorto‐pulmonary fistulation in Friesian horses in terms of clinical and post mortem data based on 24 cases. Methods: Friesian horses that were diagnosed with aortic rupture and aorto‐pulmonary fistulation over a period of 13 years (1997–2010) at the Department of Equine Sciences of Utrecht University (n = 15) and Wolvega Equine Hospital (n = 9), were included in this study. Case history, results of clinical examination and gross post mortem findings were screened and analysed. Results: Some cases were found dead without prior symptoms, but in several cases signs such as recurrent colic, peripheral oedema and sustained tachycardia were present for several weeks prior to cardiac failure. Clinical examination during hospitalisation revealed increased rectal temperature, peripheral oedema and increased jugular pulse with a bounding arterial pulse. In the majority of horses an aortic rupture of the aortic arch near the ligamentum arteriosum, concurrent with a circumferential cuff of perivascular haemorrhage and aorto‐pulmonary fistulation, was found at post mortem examination. Conclusions: Aorto‐pulmonary fistulation in conjunction with aortic rupture is more common in Friesians than previously estimated. In some cases findings demonstrate a progressive pathology rather than acute cardiac failure and sudden death. An appropriate approach is necessary during post mortem examination of the heart in order not to overlook the diagnosis. Potential relevance: Equine practitioners should realise that in Friesian horses presented with a history of recurrent false colic, coughing, sustained tachycardia and/or peripheral oedema, aortic rupture and aorto‐pulmonary fistulation should be included in the differential diagnosis. 相似文献
985.
Reasons for performing study: The use of two‐dimensional speckle tracking (2DST) for quantification of left ventricular (LV) function has recently been described in horses using long‐axis images and short‐axis images at chordal but not at papillary muscle level. Objectives: To compare the feasibility and reliability of 2DST for quantification of circumferential and radial LV function in short‐axis images at papillary muscle and chordal level. Methods: Repeated echocardiographic examinations were performed on 10 healthy trotter horses by 2 observers from a right parasternal short‐axis view at papillary muscle and chordal level. Segmental and averaged peak values and timing of circumferential and radial strain and strain rate, radial displacement and rotation were measured in 6 LV wall segments in each imaging plane. Global peak values were calculated for circumferential strain and strain rate. The inter‐ and intraobserver within‐ and between‐day variability was assessed by calculating coefficients of variation for repeated measurements. Results: 2DST analysis was feasible in each cardiac cycle, although tracking was often inadequate during early diastole. Measurements of averaged systolic circumferential and radial strain and strain rate and radial displacement as well as global circumferential strain and strain rate could be determined with low variability. Early and late diastolic strain rate and systolic rotation showed a moderate variability. Radial segmental measurements were more reliable than circumferential measurements. The interventricular septum showed a higher circumferential and lower radial strain compared with the LV free wall. Peak timing was earlier at papillary muscle compared with chordal level. Conclusions: 2DST measurements of global and regional circumferential and radial LV wall motion are feasible both at papillary muscle and chordal level. Potential relevance: Several measurements had good reliability and should be used for evaluation of the technique in a clinical setting. 相似文献
986.
987.
Mariette van den BergSimone O. Hoskin PhD Chris W. Rogers Alex Grinberg PhD 《Journal of Equine Veterinary Science》2013
Abrupt dietary transitions and feeding of rapidly fermentable diets are common practices in the horse industry and have been associated with digestive and metabolic disorders that can impair the performance of horses. The present study investigated the effect of dietary transition from pasture grazing to confinement with concentrate feeding, and back, on fecal pH and bacterial populations of Streptococcus spp and Lactobacillus spp. Six Thoroughbred fillies, previously grazing perennial ryegrass and white clover-based pasture, were housed in individual stalls and fed an increasing ratio of concentrate to conserved forages for 13 days (days 1-13), followed by an abrupt transition back to only pasture-grazing for 3 days (days 14-16). The concentrate was initially offered at 0.83 kg dry matter (DM)/d and increased to 5 kg DM/d, whereas ensiled alfalfa was initially offered at 0.61 kg DM/d, increasing to 1.22 kg DM/d. Meadow hay was initially offered at 6.73 kg DM/d, decreasing to 1.6 kg DM/d. Fecal specimens were collected daily for determination of pH, and every 2 days for quantitative analysis of Streptococcus spp and Lactobacillus spp. Mean fecal pH increased significantly from pasture baseline values (pH 6.18) during the initial confinement and supplementation on day 1 (6.37), day 2 (6.52), day 3 (6.58), and day 4 (6.43) (standard error of mean [SEM]: 0.056; P < .001). By day 5, mean fecal pH values had decreased to, and remained at, baseline values until the horses returned to pasture, when another increase occurred at day 15 (6.45). Fecal colony forming units (cfu) of Streptococcus spp and Lactobacillus spp increased linearly (r = 0.94; P < .001) from 6.0 and 6.1 log10 cfu/g on day -4, to 7.8 log10 cfu/g on day 14 (SEM: 0.2 P < .001), respectively. Fecal cfu decreased on return to a pasture-only diet (P < .001). In this study, the increment of bacterial populations was associated with a relatively stable fecal pH and highlights the difficulty in identifying the effects of dietary transition on the equine hindgut health, without microbial culture. 相似文献
988.
989.
990.
A practical method in use in South Africa for quantifying the extent of splitting in the timber of the genus Eucalyptus in order to determine minimum standards for selection purposes, is explained. The standards are used to assist in the choice of phenotypes, the progeny of which it is hoped will produce timber which splits less. 相似文献