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991.
There is limited information available on the morphology of the thoracic limb of the ring‐tailed lemur (Lemur catta). This study describes the morphology of the thoracic limb of captive ring‐tailed lemurs evidenced by gross osteology and radiography as a guide for clinical use. Radiographic findings of 12 captive ring‐tailed lemurs are correlated with bone specimens of three adult animals. The clavicle is well developed. The scapula has a large area for the origin of the m. teres major. The coracoid and hamate processes are well developed. The lateral supracondylar crest and medial epicondyle are prominent. The metacarpal bones are widely spread, and the radial tuberosity is prominent. These features indicate the presence of strong flexor muscles and flexibility of thoracic limb joints, which are important in arboreal quadrupedal locomotion. Furthermore, an ovoid ossicle is always seen at the inter‐phalangeal joint of the first digit. Areas of increased soft tissue opacity are superimposed over the proximal half of the humerus and distal half of the antebrachium in male animals as a result of the scent gland. Knowledge of the morphology of the thoracic limb of individual species is important for accurate interpretation and diagnosis of musculoskeletal diseases.  相似文献   
992.
Traditional veterinary anatomical models describe the branches of the caudal gluteal artery as the iliolumbar, cranial gluteal, lateral caudal, satellite of the ischiatic nerve and dorsal perineal arteries. However, some classical veterinary anatomy textbooks often indicate variations the general organization of the arterial tree, without giving any pattern of origin or illustrations of the different branching. The aim of this study was to investigate the presumptive variability of the caudal gluteal artery. Two hundred and thirty‐two pelvic halves from 116 adult dogs were examined. Twelve anatomical variations were found, nine occurring in more than 5% of the dogs, and three in <5%. A ‘long‐type’ internal iliac artery, which means short caudal gluteal and internal pudendal arteries, was identified, while a ‘perineal trunk’ was observed as an interesting arterial variation. If the caudal segment alone is taken into consideration, identical vascular patterns in both hemi‐pelvises are found in 17% of the dogs. Significant statistical correlation was found for four different types of anatomic variations and gender, two types of variations and body size, one type of variation for body side and one type of variation for head shape.  相似文献   
993.
Plastic hematocrit tubes (PHTs) are convenient tools for electron microscopy (EM) of peripheral blood buffy coats, and the PHT‐EM technique is expected to be a practical method for veterinary clinical medicine. In this study, fixatives composed of various concentrations of sucrose, glutaraldehyde, and phosphate buffer (PB) were tested for preparing canine and feline buffy coats. The highest quality images were obtained using a fixative consisting of 2.5% glutaraldehyde in 0.1 m PB, and it was concluded that this method allows clinicians who are inexperienced in histological techniques can conveniently transport buffy coat samples to diagnostic laboratories for analysis by EM.  相似文献   
994.
This study describes the distribution of galanin (Gal) and galanin receptor 2 (GalR2) in the pre‐optic area (POA) of the female guinea pig. Frozen sections were undergone for a routine immunofluorescence labelling. Gal and GalR2 display immunoreactivity in all parts of the pre‐optic area. Gal shows reactivity both in perikarya and fibres, whereas GalR2 was observed only in perikarya. Gal‐ and GalR2‐immunoreactive (‐ir) perikarya were the most numerous in the medial pre‐optic area (MPA) with the highest reactivity in its dorsal part. In the median pre‐optic nucleus (MPN) and periventricular pre‐optic nucleus (PPN), only single Gal‐ and GalR2‐ir neurons were observed. The highest density of Gal‐ir fibres was revealed in the PPN and the lowest in the lateral pre‐optic area (LPA). The results of this study indicate that the distribution pattern of Gal containing neurons overlaps well with the distribution pattern of GalR2‐positive neurons, especially in the MPA. This may suggest GalR2‐dependent activity in this brain region.  相似文献   
995.
Our previous study revealed the expression of substance P (SP) and calcitonin gene‐related peptide (CGRP) in sensory distal ganglion of the vagus (nodose ganglion) neurons in the pig. As these neuropeptides may be involved in nociception, the goal of these investigations was to determine possible expression of vasoactive intestinal polypeptide (VIP), SP and CGRP in the pituitary adenylate cyclase‐activating polypeptide‐immunoreactive (PACAP‐IR) porcine nodose perikarya. Co‐expression of these substances was examined using a double‐labelling immunofluorescence technique. To reveal the ganglionic cell bodies, the pan‐neuronal marker protein gene product 9.5 (PGP 9.5) was used. Quantitative analysis of the neurons revealed that 67.25% of the PGP 9.5+ somata in the right‐side ganglion and 66.5% in the left side, respectively, co‐expressed PACAP‐IR. Moreover, 60.6% of the PACAP‐IR cells in the right‐side ganglion and 62.1% in the left, respectively, co‐expressed VIP. SP‐IR was observed in 52.2 and 39.9% of the right and left ganglia, respectively. CGRP was found in 27.7 and 34.1% of the right and left distal ganglion of the vagus, respectively. High level of co‐expression of PACAP with VIP, SP and CGRP in the distal ganglia of the vagus sensory perikarya directly implicates studied peptides in their functional interaction during nociceptive vagal transduction.  相似文献   
996.
We document the anatomical architecture and frequency of occurrence of variations in the branching pattern of the brachiocephalic artery and the origin of the internal iliac arteries in the domestic cat, a widely used model organism in both anatomical training and research. Based on the study of 56 preserved specimens, we observed three distinct arrangements in the branching pattern of the brachiocephalic artery. The most common pattern (52% of the examined specimens) was that in which the brachiocephalic artery was divided into two branches, the left common carotid artery and a common branch for the right subclavian artery and the right common carotid artery. The frequency of occurrence of each variation type was independent of the gender and body size. The internal iliac arteries originated caudal to the point at which the external iliac arteries branched off from the abdominal aorta. However, the portion of the abdominal aorta between the external and internal iliac arteries varied greatly in length and was not significantly correlated with its width, nor with body size or gender. This study is the first to report and quantify the occurrence of such variations in North American cats. Given the anatomical similarity between the cat and other felids, the results of this study can be applied to other species, including endangered species.  相似文献   
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