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51.
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本研究以过氯乙烯血管铸型法和大体解剖法研究肾动脉在肾内的分支。新疆细毛羊肾属表面平滑的单乳头肾,在肾的正中额面上髓质合成一肾总乳头,但在两侧额面上肾锥体是分开的,每侧的肾锥体一般为7个。肾动脉由肾门入肾,经过2~4级分支,到相邻锥体之间为叶间动脉,每侧一般有叶间动脉8条。分其支类型有背腹型、前后型、三支型等。  相似文献   
53.
分析了SMM在健康家兔及肾损害兔体内的药物动力学过程。12只家兔分为A、B两组。A组为健康对照组,B组为肾功能损害病理模型组。A、B两组家兔均以140 mg/kg(SMM)剂量耳静脉注射SMM-Na,给药前心脏采血0.5 mL,作为空白对照。分别于给药后0.08、0.25、0.5、1、2、3、4、6 h各采血0.5 mL。以Annino法分析游离SMM血药浓度。结果显示,SMM在家兔体内药物动力学配置符合二室开放模型。药时曲线最佳方程为:C正常=13.910e-6.830t 32.569e-1.076t,C肾损害=15.748e-4.542t 27.473e-0.323t。肾损害时药动学参数与健康时的比较,α下降了33.49%;β下降了69.98%;t1/2α增加了41.03%;t1/2β增加了237.5%;AUC增加了33.49%;CLB下降了69.98%。表明家兔肾功能损害后,SMM在其体内消除显著变慢。提示在肾脏损害时应相应增大SMM给药间隔时间或减小给药剂量。  相似文献   
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为建立一种安全、简便和可靠的雄性大鼠亚慢性镉中毒模型,选取30只Wistar雄性大鼠随机分组后,每天分别用含1.25、2.5、5和10 mg/kg剂量的CdCl2溶液灌胃,研究镉离子在不同处理时间对雄性大鼠肝脏和肾脏的损伤情况.结果显示,大鼠血液和肝肾中的镉含量及血清中的尿素浓度与镉离子呈剂量效应关系.染镉56 d后,...  相似文献   
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Horses with cranial rib abnormalities may exhibit severe acute lameness and may have unusual gait deficits characterized by forelimb abduction during protraction at the walk. Horses with caudal rib abnormalities may resent being saddled and ridden. In a retrospective evaluation of 20 horses with a documented rib lesion, 25 sites of increased radiopharmaceutical uptake were found in one or more ribs. Thirteen (52%) scintigraphic lesions involved the first rib; four were located immediately dorsal to the sternal articulation, eight were near the costochondral junction and one was at the costovertebral junction. Six (24%) scintigraphic rib lesions involved ribs 2–8; one was located immediately dorsal to the sternal articulation, three were at the costovertebral junction and two were near the costochondral junction. Six (24%) scintigraphic rib lesions involved the mid‐portion (five) or costovertebral junction (one) of ribs 9–18. The 20 horses were divided into three groups based on the clinical relevance of the scintigraphic findings. Group 1 (n=3) horses had clinical signs attributed to a rib abnormality; Group 2 (n=6) horses had a rib abnormality that was a plausible explanation for clinical signs; Group 3 (n=11) horses had clinical signs that could not be attributed to a rib abnormality. For horses with cranial rib abnormalities, a modified lateral scintigraphic image with the ipsilateral limb pulled caudally and a left (right) 45° caudal–right (left) radiograph facilitated the diagnosis.  相似文献   
58.
The kidneys of three clinically normal horses were evaluated ultrasonographically, utilizing a standardized approach. The normal renal architecture, including cortex, medulla, pyramids, renal sinus fat, collecting system, and intrarenal vessels, was evaluated.
A horse with hematuria was examined in the same manner and a mass was found in the right renal pelvis.
Ultrasonographic determinations were correlated with gross anatomy, clinical signs, and pathologic findings of a renal pelvic adenoma.  相似文献   
59.
THE SCINTIGRAPHIC EVALUATION OF SOLID PHASE GASTRIC EMPTYING IN NORMAL CATS   总被引:1,自引:0,他引:1  
The gastric emptying half-time of solid food in normal cats was determined using a scintigraphic technique. 99mTc-sulfur colloid was applied to dry food. Sequential images were acquired post prandial, and the gastric emptying half-time was determined for several different acquisition and processing parameters. Good correlation was found between different acquisition and processing methods, some of which made use of edge detection applications, while others used different views, or number of views from which the gastric emptying half-time was calculated. The mean ± standard deviation, (range) and median of the gastric emptying half-time determined using the geometric mean of total counts in hand-drawn regions of interest from the lateral and ventral images were 2.47 × 0.71, (1.42–3.61) and 2.37 hours respectably.  相似文献   
60.
The pattern of the specific 5-HT2A (5-hydroxytryptamine 2A receptor) antagonist 123I-5-I-R91150 was measured in 10 healthy dogs without neurologic and behavior abnormalities. Eight cortical regions (left and right fronto-, temporo-, parieto-, and occipitocortical area), one global subcortical region (including the thalamic system) were compared with a reference region lacking receptors; that is, the cerebellum. The 123I labeled radioligand was injected intravenously 100-200 minutes before acquisition. Both transmission and emission data were obtained with a triple head gamma camera equipped with high-resolution fanbeam collimators. The emission data were corrected for scatter and attenuation. To delineate different cerebral regions more accurately, the regions of interest (ROI) defined in a former study on brain perfusion measured with 99mTc-ethyl cysteinate dimer (ECD) in the same dogs were used. The co-registration of the 99mTc-ECD and the 123I-5-I-R91150, obtained from each dog, was realized with the help of corresponding transmission maps. By normalizing each regional cerebral activity to the activity observed in the cerebellum, the regional radioactivity (binding index) could be relatively quantified. Highest brain uptake was noted in the frontocortical brain areas (right: 1.85, left: 1.89), followed by the temporocortical region (right: 1.58, left: 1.56). Least uptake was noted in the more caudal and middle brain regions [occipito- (right: 1.46, left: 1.41), parietocortical (right: 1.30, left: 1.26), and striatal region (1.19)]. No gender nor age influence was noted in this series. The 123I labeled serotonin-2A receptor ligand seems to have similar cortical binding in the normal canine brain, as shown in humans and other animal species. A frontocortical to occipitocortical (rostrocaudal) binding index gradient was identified within the dog, which has not been seen in imaging studies from humans and other animal species. The significance of these results will need further investigation. This normative data can be used to compare regional brain uptake of the 123I-radioligand to dogs with behavioral disorders related to the serotonergic system, in future studies.  相似文献   
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