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1.
In humans, contrast-enhanced magnetic resonance angiography (CE-MRA) is a documented method to quantitatively and qualitatively evaluate renal vessels. It offers a safer alternative to computed tomography angiography. The aim of this study was to establish a renal MRA protocol in dogs using a 3D multiphase Fast Spoiled Gradient Recalled echo CE-MRA sequence (3D FSPGR CE-MRA). We used an elliptical centric ordering of k -space to acquire the contrast-sensitive data faster. Four to five consecutive 3D dorsal slabs, encompassing both kidneys, could be acquired in 40–65 s. The renal arterial and venous phases were obtained separately during phases 1 or 2, and 2 or 3, respectively without the need for any contrast medium bolus timing. The renal arteries and veins were clearly visualized. In conclusion, multiphase FSPGR 3D CE-MRA with an elliptical centric k -space ordering allows distinguishing renal arterial and venous phases in dogs, and can be used as a noninvasive diagnostic imaging alternative to map renal vessels in this species. Potential applications include the screening of renal donors in renal transplantation programs, and the pretreatment evaluation of animals with invasive renal neoplasia or renal vascular anomalies when surgery or embolization are contemplated.  相似文献   
2.
A 10-year-old male cat was presented with sudden onset of respiratory difficulties. Clinical examinatlon revealed an acute dyspnoea with cyanosis associated with a left systolic heart murmur. Standard thoracic radiographs excluded pulmonary oedema and showed very few pulmonary changes given the intensity of the respiratory compromlse. Echocardiographic examination revealed hypertrophic cardiomyopathy and a thrombus In the right pulmonary artery. Pulmonary sclntlgraphy confirmed a pulmonary thromboembolism with hypovascularisatlon of the left cranial lobe and of the ventral segment of the right lobe. Conservative treatment was instituted using an antibiotic (doxycycllne), anticoagulants (heparin, coumadine) and a calcium lnhlbitor (diltiazem). The cat was given absolute rest. The general condition of the animal improved.  相似文献   
3.
为获得生长在沙漠深处不同类型桑树基因资源的持水力差异信息,采用自然脱水法,对黑桑、白桑、粉桑和雄桑等不同类型的20份沙漠桑基因资源的失水过程进行了测定;研究结果表明,沙漠桑树分为强持水型、中等持水型和弱持水型,黑桑、白桑和粉桑类型桑树的持水能力较雄桑类型桑树强;根据枝条、叶片等同器官持水能力强弱不同,多数沙漠桑叶片的持水能力不太强,初步认为枝条的持水能力较叶片强。  相似文献   
4.
鲆鲽鱼营养生理研究进展   总被引:2,自引:0,他引:2  
本文综述了鲆鲽鱼类营养生理的研究进展,涉及鲆鲽鱼对蛋白质、氨基酸、脂肪、必需脂肪酸、碳水化合物、维生素和微量元素的需要量及各种营养元素的生理功能,评价饲料中各营养素缺乏和过量对鲆鲽鱼生长的影响,以及各营养素之间的相互关系。  相似文献   
5.
Diagnosis of acute primary splenic torsion is challenging. The ultrasonographic appearance of this condition has been described, but other splenic diseases, such as diffuse infarction because of thrombosis, can appear very similar. We describe an additional ultrasonographic sign of acute splenic torsion; a triangular hyperechoic area at the hilus between the veins and the splenic parenchyma that is continuous with the hyperechoic mesentery. In a group of animals where acute splenic torsion was part of the ultrasound report differential diagnosis, we compared findings in dogs with torsion with findings in dogs with other splenic conditions. The presence of a hilar hyperechoic perivenous triangle was significantly associated with splenic torsion (P = 0.005). We speculate that this sign is associated with torsion because of the secondary severe, diffuse splenic enlargement. Although not pathognomonic, this sign could be used to more accurately diagnose splenic torsion in light of other findings consistent with this condition.  相似文献   
6.
本文就如何提高生产管理的技术水平和经济效益,谈谈肉用商品鸭散户饲养管理的一些看法。1选择优良品种饲养肉用商品鸭目前基本选择樱桃谷杂及丽  相似文献   
7.
为了更好地开展中兽医药与方剂学课程的教学和科学研究,使学生了解和掌握中草药物和方剂的理论学习,通过制作中草药饮片标本、干制标本、蜡叶标本和浸制标本,不断地建立和完善中草药标本室,也可以通过中草药标本二维码数据库的建立、常见植物标本的种植栽培,以及野外采集中草药实践教学的实施,提高学生对中兽医药与方剂学课程的学习质量,以期为今后临床实践和应用打下良好的理论基础。  相似文献   
8.
Gadolinium‐enhancement of compressive extradural material is detected occasionally with magnetic resonance (MR) imaging in dogs. Our goal was to characterize contrast enhancement of extradural compressive material associated with intervertebral disc herniation, and to evaluate the association between enhancement and histopathologic findings and the onset of clinical signs. Ninety‐three dogs with a total of 99 lesions diagnosed as intervertebral disc herniation on MR imaging were assessed. Images were evaluated for lesion location, type of herniation, degree of compression, intramedullary T2‐weighted (T2W) intensities, and contrast enhancement. In 23 dogs, surgically removed compressive material was evaluated histopathologically for hemorrhage, inflammation, neovascularization, fibroplasia, fibrosis, mineralization, necrosis, and chronicity. Contrast enhancement of extradural compressive material, meninges, and both the compressive materials and meninges was present in 51.5%, 39.4%, and 17.2% of lesions, respectively. Extradural enhancement occurred more frequently in extrusions than protrusions (P=0.001). Meningeal enhancement and more severe neurologic deficits were significantly associated with a shorter duration of clinical signs (P=0.04 and 0.01, respectively). Intramedullary T2W hyperintensities, present with 44.4% of lesions, were associated with more severe neurologic deficits (P=0.001). Lesions with extradural enhancement were more often considered subacute to chronic in duration and more frequently associated with hemorrhage compared with nonenhancing material; however, no statistically significant association was established between contrast enhancement and histopathologic findings. Contrast enhancement of extradural compressive material and the meninges was found to be common with intervertebral disc herniation, and should not be interpreted as a specific sign of a mass lesion such as neoplasia.  相似文献   
9.
The purpose of this study was to investigate the association between renal hypoechoic subcapsular thickening observed ultrasonographically and the presence of renal lymphosarcoma in cats. The ultrasonography database was retrospectively searched for cats that underwent ultrasound examination and ultrasound guided needle renal aspirate, renal biopsy, or necropsy. One radiologist unaware of the final diagnosis evaluated the images for the presence of hypoechoic subcapsular thickening and other abnormal findings. Fifty-four cats met the inclusion criteria. Hypoechoic subcapsular thickening was found in 21 cats of which 17 had lymphosarcoma; the remaining four cats had a different diagnosis. Eleven out of 33 cats without hypoechoic subcapsular thickening were positive for lymphosarcoma, and the rest had a different diagnosis. There was a significant association between hypoechoic subcapsular thickening and renal lymphosarcoma (P = 0.001). The positive predictive value of hypoechoic subcapsular thickening for lymphosarcoma was 80.9% and the negative predictive value was 66.7%. The sensitivity and specificity of hypoechoic subcapsular thickening for the diagnosis of renal lymphosarcoma were 60.7% and 84.6%, respectively. The results of this study indicate that the presence of hypoechoic subcapsular thickening in feline kidneys is associated with renal lymphosarcoma.  相似文献   
10.
利用同源克隆技术和cDNA末端快速扩增(RACE)技术克隆大黄鱼胞质型磷脂酶A2(cPLA2)基因的cDNA全长.此外,应用实时定量PCR法检测不同日龄大黄鱼仔稚鱼cPLA2基因的表达量.序列分析结果表明:cPLA2基因全长2 550 bp(GenBank登录号:KF006240.1),其中5'端非编码区176 bp,开放阅读框2 169 bp,3'端非编码区205 bp,共编码723个氨基酸.系统进化树分析结果表明:克隆所得大黄鱼cPLA2基因与其他鱼类的cPLA2基因亲缘关系较近,与哺乳动物的亲缘关系较远.定量检测结果表明:大黄鱼仔稚鱼cPLA2基因的表达量随日龄的增加为先显著升高(1、3、7日龄vs.15日龄,P<0.05),在15日龄时达到最高值,随后显著下降(15日龄vs.19日龄,P<0.05),之后趋于平稳.由此可知,大黄鱼从仔稚鱼到幼鱼早期的变形过程中,磷脂分解代谢的关键酶cPLA2基因的表达量呈现有规律的变化,这可能对机体保持体内磷脂的动态平衡、维护细胞膜的流动性具有重要的意义.大黄鱼仔稚鱼cPLA2基因表达量的变化趋势在一定程度上可以衡量大黄鱼消化系统的发育情况.  相似文献   
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