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A 3-year-old sexually intact male Bull Mastiff underwent splenectomy for splenic thrombosis; prior to and after splenectomy, multiple blood transfusions were administered. Two weeks after the procedure, T-cell lymphoproliferative disease was diagnosed. Treatment with prednisone and chlorambucil was initiated, and 2 weeks later, cytologic examination of a blood smear revealed small (0.3 microm), coccoid basophilic bodies on the surface of approximately 70% of the RBCs. Morphologically, these resembled "Candidatus Mycoplasma haemominutum." A polymerase chain reaction assay was used to amplify a partial 16S rRNA sequence in blood obtained from the dog; the product was sequenced and compared with 16S rRNA gene sequences of other hemotropic mycoplasmas. The sequence was 98% homologous to that of "Candidatus M haemominutum", but only 77% homologous to that of M haemocanis and M haemofelis.  相似文献   
23.
Using light microscopic immunohistochemistry, neuron-specific enolase (NSE)-positive endocrine cells were quantitatively analyzed in the sheep lung during different stages of development from the canalicular stages to adulthood. In all stages, NSE-positive endocrine cells were usually located in the bronchi and bronchioles as solitary cells, although a few NSE-positive cell clusters, the so-called neuroepithelial bodies, were found in some places. The number of NSE-positive endocrine cells decreased with advanced stages of gestation. In the late alveolar stage, the number of NSE-positive endocrine cells reached its bottom during the fetal period. There was a gradual upturn after birth. The overall pattern of growth and differentiation of the endocrine cells is most likely species-related and depends on the state of airway development; the number of the endocrine cells of almost all animals, excluding the sheep, in relation to the size of the lung reaches a peak in the late fetal and early neonatal periods and decreases shortly thereafter. NSE-positive endocrine cells were also predominantly located in the large airways during the early stage of development (canalicular stage), and were found more frequently in the small peripheral airways towards the term. These results show the number of NSE-positive endocrine cells in the sheep to be different from that seen in other species.  相似文献   
24.
Total joint replacement has evolved over the past 50 years from a concept that was first attempted in people suffering from osteoarthritis to a commonly applied practice in veterinary medicine. Although many questions have been answered, several controversies still exist, with many implant and technical options being explored. Currently, total hip and elbow replacement are commercially available options viable for use in dogs. These options are detailed in this article.Joint replacement for other canine joints (ie, knee, hock, shoulder) that develop osteoarthritis likely will be developed in the near future.  相似文献   
25.
Poultry-derived food is a common source of infection of human with the non-host-adapted salmonellae while fowl typhoid and pullorum disease are serious diseases in poultry. Development of novel immune-based control strategies against Salmonella infection necessitates a better understanding of the host-pathogen interactions at the cellular level. Intestinal epithelial cells are the first line of defence against enteric infections and the role of macrophages is crucial in Salmonella infection and pathogenesis. While gene expression following Salmonella infection has been investigated, a comparison between different serovars has not been, as yet, extensively studied in poultry. In this study, chicken macrophage-like cells (HD11) and chick kidney epithelial cells (CKC) were used to study and compare the immune responses and mechanisms that develop after infection with different Salmonella serotypes. Salmonella serovars Typhimurium, Enteritidis, Hadar and Infantis showed a greater level of invasion and/or uptake characters when compared with S. Pullorum or S. Gallinarum. Nitrate and reactive oxygen species were greater in Salmonella-infected HD11 cells with the expression of iNOS and nuclear factor-κB by chicken macrophages infected with both systemic and broad host range serovars. HD11 cells revealed higher mRNA gene expression for CXCLi2, IL-6 and iNOS genes in response to S. Enteritidis infection when compared to S. Pullorum-infected cells. S. Typhimurium- and S. Hadar-infected HD11 showed higher gene expression for CXCLi2 versus S. Pullorum-infected cells. Higher mRNA gene expression levels of pro-inflammatory cytokine IL-6, chemokines CXCLi1 and CXCLi2 and iNOS genes were detected in S. Typhimurium- and S. Enteritidis-infected CKC followed by S. Hadar and S. Infantis while no significant changes were observed in S. Pullorum or S. Gallinarum-infected CKC.  相似文献   
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Anterior pituitary gland contents of LH and LHß- and α-subunit mRNAs, and circulating concentrations of LH and testosterone, were determined in bulls treated with the LH-releasing hormone (LHRH) agonist deslorelin. Brahman (Bos indicus) bulls (14-month-old) were allocated to two groups and received the following: Control (n = 5), no treatment; Deslorelin (n = 4), four deslorelin implants (approximately 200 μg total deslorelin/day) for 36 d. Plasma concentrations of LH were higher in bulls treated with deslorelin on Day 1, had returned to typical levels by Day 8, and did not differ for control bulls and bulls treated with deslorelin from Day 8 to Day 29. Pituitary content of LH on Day 36 was reduced (P < 0.001) in bulls treated with deslorelin (33 ± 4 ng/mg) compared with control bulls (553 ± 142 ng/mg). Relative pituitary content of LHß-subunit mRNA was also reduced on Day 36 in bulls treated with deslorelin (Control, 0.65 ± 0.10; Deslorelin, 0.22 ± 0.04; P = 0.003). However, α-subunit mRNA relative content did not differ (Control, 0.73 ± 0.15; Deslorelin, 1.06 ± 0.12; P > 0.05). Plasma concentrations of testosterone were increased over the period of the experiment in the bulls treated with deslorelin compared with control bulls. This is the first demonstration of reduced pituitary content of LHß-subunit mRNA and LH, and unaltered content of α-subunit mRNA, in bulls treated with LHRH agonist. This was associated with apparently typical plasma concentrations of LH and elevated plasma testosterone. The anterior pituitary in bulls treated with LHRH agonist, therefore, undergoes classical desensitization and downregulation, but plasma LH and testosterone are not suppressed.  相似文献   
28.
OBJECTIVE: To compare the mechanical properties of 4 stabilization methods for equine long-bone fractures: dynamic compression plate (DCP), limited contact-DCPlate (LC-DCP), locking compression plate (LCP), and the clamp-rod internal fixator (CRIF--formerly VetFix). STUDY DESIGN: In vitro mechanical study. SAMPLE POPULATION: Bone substitute material (24 tubes) was cut at 20 degrees to the long axis of the tube to simulate an oblique mid-shaft fracture. METHODS: Tubes were divided into 4 groups (n=6) and double plated in an orthogonal configuration, with 1 screw of 1 implant being inserted in lag fashion through the "fracture". Thus, the groups were: (1) 2 DCP implants (4.5, broad, 10 holes); (2) 2 LC-DCP implants (5.5, broad, 10 holes); (3) 2 LCP implants (4.5/5.0, broad, 10 holes) and 4 head locking screws/plate; and (4) 2 CRIF (4.5/5.0) and 10 clamps in alternating position left and right of the rod. All constructs were tested in 4-point bending with a quasi-static load until failure. The implant with the interfragmentary screw was always positioned on the tension side of the construct. Force, displacement, and angular displacement at the "fracture" line were determined. Construct stiffness under low and high loads, yield strength, ultimate strength, and maximum angular displacement were determined. RESULTS: None of the implants failed; the strength of the bone substitute was the limiting factor. At low loads, no differences in stiffness were found among groups, but LCP constructs were stiffer than other constructs under high loads (P=.004). Ultimate strength was lowest in the LCP group (P=.01), whereas yield strength was highest for LCP constructs (409 N m, P=.004). CRIF had the lowest yield strength (117 N m, P=.004); no differences in yield strength (250 N m) were found between DCP and LC-DCP constructs. Differences were found for maximum angular displacement at the "fracture" line, between groups: LPC相似文献   
29.
River dolphins are especially susceptible to negative human impacts. For their conservation, attempts of relocation or procreation ex situ may become important in the future to avoid their extinction. Additional knowledge and medical experiences of river dolphin management in captivity may aid such conservation efforts. The medical records and necropsy and histopathology reports on 123 captive Amazon River dolphins (Inia geoffrensis) were re-viewed. Of these 123 animals, 105 were necropsied and 70 necropsies were supported with histopathology. Eighteen animals were not necropsied. Among wild-born animals, mortality was highest in the first 2 mo immediately postcapture and transport, accounting for 32 of 123 deaths. Pneumonia and skin lesions (cutaneous and subcutaneous ulcerations and abscesses) were the most common findings, found in 44 of 105 (42%) and 38 of 105 (36%) of gross diagnoses, respectively. At least 10 of 44 cases of pneumonia diagnosed grossly included a verminous component. Cachexia, from a variety of causes, was a major gross finding in 21 animals. Fifteen animals had histologic evidence of significant renal pathology, and this was the primary cause of death in 13 cases. Hepatic pathology was found in 18 cases, and bacterial sepsis was confirmed via histology in 16 cases. Based on these findings, it may be concluded that keys to successful maintenance of this species include 1) prophylactic anthelminthic and antibiotic therapy immediately post-capture; 2) maintenance of animals in larger enclosures than in past attempts, in compatible groups, and in facilities capable of separating aggressive animals; 3) maintenance in microbiologically hygienic water quality at all times; and 4) a proactive program of preventive medicine during the immediate postcapture, quarantine, and maintenance period of captivity.  相似文献   
30.
99mTc-methylene diphosphonate (MDP) radionuclide imaging examinations were done in four horses having clinical evidence of skull trauma or infection. Radiographs were made of each horse prior to scintigraphy. Four case histories are presented. In each instance, scintigraphy provided complementary information to that obtainable through radiography, which aided in accurately localizing and characterizing the site and extent of abnormalities, and which proved particularly valuable as an aid for therapeutic planning.  相似文献   
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