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601.
The nasal cycle is a physiological phenomenon that causes regular cyclical congestion and decongestion of the venous sinusoids lining the nasal mucosa. The purpose of this prospective study was to describe magnetic resonance imaging (MRI) and computed tomographic (CT) features of the normal nasal cycle in a group of dogs. Five dogs were recruited that met the following criteria: 8 to 15 months old, nonbrachiocephalic breed, no clinical signs or history of nasal disease, and undergoing anesthesia for problems unrelated to the nasal cavity. Nasal MRI (n = 5) and CT scans (pre‐ and postcontrast, n = 5) were acquired. Images were evaluated subjectively by two board‐certified radiologists and objectively by a diagnostic imaging intern using regions of interest placed on each side of the nasal cavity. Findings were compared using Cohen's kappa coefficient and Students t‐test on log‐transformed data. All dogs showed diffuse unilateral mucosal thickening of the rostral part of the nasal cavity in both MRI and CT studies. This mucosal thickening shifted sides between examinations in three dogs. Changes appeared most marked on T2‐weighted scans. No asymmetric mucosal changes were seen in the mucosa of the ethmoturbinates, vomer–nasal septum, hard palate or the frontal sinuses in any patient on MRI or CT. Computed tomographic contrast enhancement of the thickened mucosa was not statistically significant (P‐value < 0.08). In conclusion, the normal nasal cycle may cause asymmetrical mucosal changes in the rostral part of the nasal cavity that mimic MRI and CT characteristics previously reported for inflammatory disease in dogs. 相似文献
602.
AIM:To investigate the effects of Qili Qiangxin capsule on serum adiponectin (APN), serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and heart function in the patients of coronary heart disease combined with congestive heart failure. METHODS:One hundred and twenty patients were randomly divided into treatment group and control group, and both groups were given anti-failure routine therapy. The patients in treatment group were treated with Qili Qiangxin capsule and the patients in control group were treated with placebo. The patients in the 2 groups were given a certain dose of the drugs for 6 months. The New York Heart Association (NYHA) heart function classification, left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter (LVESD),left ventricular ejection fraction (LVEF), and 6-min walking test (6-MWT) were observed before and after treatment. The levels of APN, NT-proBNP were measured by ELISA before and after treatment. RESULTS:With the increase in the class of NYHA heart function, the serum concentrations of APN and NT-proBNP in the heart failure cases increased significantly. After 6-month treatment, the effective rate in experimental group was 91.7% and that in control group was 75.0%. A significant difference was found between the 2 groups (P<0.01). After treatment, LVEDD and LVESD in both groups were decreased significantly, and LVEF in both groups was increased significantly. The serum concentrations of APN and NT-proBNP decreased significantly (P<0.05). 6-MWT result was improved significantly. Compared with control group, more obvious effect was observed in experimental group (P<0.05). CONCLUSION:Treatment with Qili Qiangxin capsule reduces the levels of APN and NT-proBNP in the patients with coronary heart disease combined with congestive heart failure. 相似文献
603.
ObjectiveTo determine how frequently the current criteria for left ventricular enlargement in dogs misclassify healthy dogs as having left ventricular enlargement; to examine the effect of breed on diastolic left ventricular normalized dimensions (LVIDDN); to propose appropriate scaling exponents and reference limits for dogs.AnimalsEchocardiographic data from 1,124 healthy adult dogs, including 454 dogs weighing <20 kg.MethodsWe calculated power regression parameters (allometric scaling), including exponents and proportionality constants, for various subsets of the dogs (all dogs, dogs < 20 kg, generic dogs, and individual breeds with >10 observations) and derived upper reference limits for LVIDDN. We determined the proportions of dogs that would be identified as having left ventricular enlargement with each regression model compared to previously published reference limits or guidelines. We then identified breeds failing to conform to generic dog models.ResultsThe American College of Veterinary Internal Medicine-recommended scaling exponent (0.294) and criterion for identifying left ventricular enlargement (1.7) identified >10% of apparently healthy dogs as having left ventricular enlargement, with specific breeds being misclassified up to 50% of the time. However, with a scaling exponent of 0.33, a constant of 1.7 represented a normal left ventricular size in 97.5% of healthy dogs in both generic and non-conforming breeds.ConclusionsLeft ventricular internal dimension in diastole normalized to bodyweight is breed-dependent. A constant of 1.7 with a scaling exponent of 0.294 does not always represent ventricular enlargement; a scaling exponent of 0.33, with breed-specific reference limits for breeds that fail to conform to allometric models of generic dogs, reduces the misclassification of healthy dogs as having left ventricular enlargement. 相似文献
604.
Congenital membranous ventricular septal aneurysm has been reported in dogs and can be associated with a perimembranous ventricular septal defect (VSD). The windsock-like ventricular septal aneurysm is formed by tissue of the membranous ventricular septum and portions of the septal leaflet of the tricuspid valve. We report two dogs that underwent transcatheter closure of perimembranous VSD associated with membranous ventricular septal aneurysm using a commercial device marketed for transcatheter closure of patent ductus arteriosus, the canine duct occluder. Partial closure was achieved in the first dog with reduction in left heart dimensions documented on echocardiography both at one day and nine months after procedure. In the second dog, three-dimensional transesophageal echocardiography, cardiac computed tomography, and a three-dimensionally printed whole heart model were used to evaluate feasibility for transcatheter device closure. Complete closure of the VSD was subsequently achieved. Both cases had good short- to medium-term outcomes, no perioperative complications were observed, and both dogs are apparently healthy and receiving no cardiac medications at 34 months and 17 months after procedure. Transcatheter attenuation of perimembranous VSD with membranous ventricular septal aneurysm is clinically feasible using the canine duct occluder, and multimodal cardiac imaging allows accurate assessment and planning prior to transcatheter intervention for structural heart disease in dogs. 相似文献