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41.
Cockatiels are popular pets. Still, despite medical and surgical relevance, the radiographic anatomy of the cockatiel (Nymphicus hollandicus) skeleton, like that of different wild and exotic bird species, has seldom been described. This study set out to describe the radiographic anatomy of the cockatiel skeleton. Twelve adult male and nine adult female specimens were radiographed using a digital X-ray system and different views. The radiographic anatomy of these birds was similar to that of other Psittacidae. However, some particularities inherent to the target species were detected, such as the presence of four flexion zones in the skull (craniofacial, nasal, jugal arch and palatine), complete bony orbit comprising a suborbital arch, 34–38 vertebrae (10 or 11 cervical, 8 or 9 thoracic, 9 or 10 lumbosacral, 5 or 6 caudal vertebrae and a pygostyle comprising 2 fused vertebrae), eight or nine pairs of ribs and a notarium made up of fused T2–T6 vertebrae. Poor radiopacity of the notarium, ribs and respective uncinate processes, and synsacral vertebrae made demarcation of these structures difficult. The appendicular skeleton of the cockatiel was very similar to that of other Psittacidae, and there were no gender-related differences.  相似文献   
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Healthy horses and other animals have large numbers of resident leukocytes in the intestinal wall, but there is scant information regarding which and how many leukocytes are normally present in the equine intestinal wall. Our aim was to provide a reference range of leukocytes in the intestinal mucosal and submucosal propria of normal horses. We included in our study intestinal tissues from 22 Thoroughbred racehorses with no clinical intestinal disease, which had been euthanized because of catastrophic musculoskeletal injuries. Neutrophils, lymphocytes, eosinophils, macrophages, and plasma cells were counted in 5 random 17,600-µm2 areas of villus lamina propria of the duodenum, jejunum, and ileum, and deep lamina propria of the duodenum, jejunum, ileum, right ventral colon, left ventral colon, left dorsal colon, right dorsal colon, and small colon. Other features investigated in the same intestinal segments included villus height and width (small intestine), presence of ciliated protozoa, Paneth cells number, subcryptal leukocyte layers (number of leukocyte layers between the bottom of the crypts and the muscularis mucosae), and submucosal leukocytes. Lymphocytes were the most numerous cells in all segments analyzed, followed by plasma cells, eosinophils, macrophages, and neutrophils. Eosinophil numbers were significantly higher in both lamina propria and submucosa of the large intestine than in the small intestine. The duodenum had shorter and thinner villi than either jejunum or ileum. The data provided from our study will be useful for diagnosticians examining inflammatory processes in the intestinal tract of horses.  相似文献   
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Computed tomographic (CT) venography of the cervical vertebral canal was performed in six, clinically normal, adult mixed-breed dogs from 14 to 23 kg. After dogs were euthanized and saline perfused, a gelatin and iothalamate mixture was injected into the right external jugular vein. Contiguous, 4-mm-thick CT images were obtained with dogs in sternal recumbency. Dogs were kept in the same position as for the CT scan and frozen to approximately -8 degrees C. All post-contrast CT images were analyzed using similar bone window and level settings. Additional multiplanar reformatted dorsal images were obtained in all dogs. The frozen cadavers were sectioned through the cervical region extending from the occiput to T1 at approximately 8-mm intervals. The frozen sections were then compared with the CT images. The CT appearance of the normal cervical vertebral venous system was described and illustrated. Components such as the internal vertebral venous plexus, interarcuate veins, intervertebral veins, and vertebral veins were clearly identified on the CT images.  相似文献   
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The rabbit, which is widely used as an experimental animal and is also popular as a companion animal, has aflat and elongated spleen with the longitudinal hilus running along its visceral surface. The spleen receivesvia the hilus an arterial supply that is essential for splenic nutrition and normal functioning. However, thedistribution and variation of the arteries to the spleen have not been studied in detail. This studyinvestigated anatomical variations of splenic arterial supply in 33 New Zealand White rabbits with a coloredlatex injection into arteries. We also examined whether the length of the spleen correlated with the number ofthe splenic branches of the splenic artery. The splenic artery always arose as the first independent branch ofthe celiac artery and ran along the splenic hilus to usually provide 6 (range, 3 to 10) splenic branches tothe spleen. There was a moderate correlation (R=0.6) between the number of splenic branchesand the longitudinal length of the spleen. The splenic branches often arose as a trunk or trunks in commonwith short gastric arteries. The number of common trunk(s) was usually 1 (range, 0 to 4). The data showed thatthe pattern and number of arterial branches to the spleen varied according to the individual animal,suggesting that such variations should be considered when performing experimental and veterinary surgicaltreatments in rabbits.  相似文献   
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Advances in magnetic resonance (MR) imaging and three-dimensional (3D) modeling software provide the tools necessary to create sophisticated, interactive anatomic resources that can assist in the interpretation of MR images of extremities, and learning the structure and function of limb musculature. Modeling provides advantages over dissection or consultation of print atlases because of the associated speed, flexibility, 3D nature, and elimination of superimposed arrows and labels. Our goals were to create a diagnostic atlas of pelvic limb muscles that will facilitate interpretation of MR images of patients with muscle injury and to create a 3D model of the canine pelvic limb musculature to facilitate anatomic learning. To create these resources, we used structural segmentation of MR images, a process that groups image pixels into anatomically meaningful regions. The Diagnostic Atlas is an interactive, multiplanar, web-based MR atlas of the canine pelvic limb musculature that was created by manually segmenting clinically analogous MR sequences. Higher resolution volumetric MR and computed tomography (CT) data were segmented into separately labeled volumes of data and then transformed into a multilayered 3D computer model. The 3D Model serves as a resource for students of gross anatomy, encouraging integrative learning with its highly interactive and selective display capabilities. For clinicians, the 3D Model also serves to bridge the gap between topographic and tomographic anatomy, displaying both formats alongside, or even superimposed over each other. Both projects are hosted on an open-access website, http://3dvetanatomy.ncsu.edu/  相似文献   
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The need for exact knowledge of the projections of internal organs onto the surface of animals is emphasized, for clinical veterinary medicine as well as for hunting purposes. A method is described for outlining the projections of dissected anatomical structures onto the exposed surface, on a photograph of the undisturbed animal in a natural standing position.  相似文献   
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利用酒精、镊子对黑木耳耳片进行组织分离,方法方便、快捷,分离成功率100%。  相似文献   
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