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11.
A bull was referred for a progressive oligoasthenotheratozoospermia that resulted in a unsuitable seminal quality for the cryopreservation. Breeding soundness evaluation results suggested gonadal dysfunction. Because of the lack of normal ranges for these hormones in the bull, in this study, the hypogonadism and the site of the dysfunction (hypothalamus) were diagnosed by the gonadotropin-releasing hormone (GnRH) stimulation test. The evaluation of pituitary and testicular responsiveness by a GnRH stimulating test revealed a responsiveness of the pituitary and testis, thus a secondary hypogonadism (hypothalamic hypogonadism) was postulated and a therapeutic approach based on the subcutaneous administration of GnRH analog was attempted. An increase in semen volume, concentration and sperm characteristics were detected 9 weeks after the start of the treatment, corroborating the hypothalamic origin of the disease and the useful of the GnRH therapy. 相似文献
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David A Jiménez Laura J Armbrust Robert T O'Brien David S Biller 《Veterinary radiology & ultrasound》2008,49(4):321-332
Digital radiography is becoming more prevalent in veterinary medicine, and with its increased use has come the recognition of a number of artifacts. Artifacts in digital radiography can decrease image quality and mask or mimic pathologic changes. They can be categorized according to the step during which they are created and include preexposure, exposure, postexposure, reading, and workstation artifacts. The recognition and understanding of artifacts in digital radiography facilitates their reduction and decreases misinterpretation. The purpose of this review is to name, describe the appearance, identify the cause, and provide methods of resolution of artifacts in digital radiography. 相似文献
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Pathogenesis in visceral leishmaniosis is associated with depressed cellular immunity and a significant rise of antileishmanial antibodies. We assessed the relative levels of immunoglobulin E anti-Leishmania infantum, together with those of IgG, IgG1 and IgG2, using the enzyme-linked immunosorbent assay (ELISA) test, in non-infected and infected dogs with or without symptoms, and their association with symptoms to differentiate the stages of the infection. The expression of all immunoglobulins (IgG, IgG1, IgG2 and IgE) was higher in symptomatic dogs than in all other categories. IgG and IgG2 expression was higher in the infected asymptomatic group than in the non-infected group, whereas IgG1 and IgE expression was only higher in symptomatic animals. This correlation between the expression of IgG1 and IgE and the pathology of leishmaniosis points to their potential role as markers of the active disease. 相似文献
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Laura N Cuypers Wim L Cuypers Amélie Gildemyn-Blomme Laura Abraham Senne Aertbeliën Apia W Massawe 《African Zoology》2017,52(2):119-123
In Africa, indigenous multimammate mice (Mastomys natalensis) only appear to live commensally in houses when invasive black rats (Rattus rattus) are absent, yet little is known about the underlying mechanism. Avoidance through smell may cause the absence of M. natalensis from areas occupied by R. rattus, but this hypothesis has not yet been tested. We conducted a Y-maze choice experiment where 15 M. natalensis were offered a choice between corridors containing conspecific scent, R. rattus scent and a control scent. Residence time in the R. rattus corridor was greater than that in the control corridor but equal to that in the M. natalensis corridor, suggesting that multimammate mice do not actively avoid the scent of their invasive competitor. 相似文献
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Laura K. McCluskie BVSc 《Veterinary surgery : VS》2010,39(7):884-890
Objective: To describe surgical technique and outcome in 10 horses with impacted cheek teeth that were removed by a transcortical osteotomy and buccotomy technique. Study Design: Case series. Animals: Horses (n=10) with impacted cheek teeth. Methods: Medical records (2002–2008) of horses with impacted cheek teeth requiring removal were reviewed; surgical technique and outcome were determined. Results: Exodontia of 11 cheek teeth was performed surgically in 10 horses; 3 horses had complications (residual swelling of the mandible) that resolved and all horses returned to their previous use. Conclusions: Transcortical buccotomy technique is effective for removal of incompletely erupted impacted cheek teeth in horses and has a good long‐term prognosis for remission of clinical signs. Clinical Relevance: Transcortical buccotomy approach is an effective technique for removal of unerupted impacted equine cheek teeth. 相似文献
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Chen SJ Foster WR Jure-Kunkel MN Girit E Abraham R Hefta LJ Gao S Yonan CR Lin JH Dambach DM 《Veterinary immunology and immunopathology》2008,126(3-4):377-381
CD137 plays an important role as a co-stimulatory molecule in activated T cells. Agonistic CD137 specific antibodies have been investigated as therapeutic agents to promote tumor-specific immune responses by direct activation of T cells. As part of the pre-clinical pharmacological evaluation of cynomolgus monkeys, monkey CD137 was cloned and characterized. The deduced amino acid sequence encoded a full-length gene of 254 amino acids 95% identical to human CD137. Sequence variants identified in monkey CD137 include four splice variants lacking the transmembrane domain. These variants were detectable in human including two previously unreported variants. Two missense single nucleotide polymorphisms were detected present in 42 and 50% of 36 monkeys tested. In both monkey and human, mRNA expression of full-length CD137 and splice variants were significantly increased in peripheral blood mononuclear cells (PBMCs) upon stimulation by anti-CD3 antibodies. Recombinant monkey CD137 protein was bound with high affinity by an agonistic anti-human CD137 antibody but not by an anti-mouse CD137 antibody. In summary, compared to human, monkey CD137 showed distinct extracellular domain amino acid sequence and sequence polymorphisms. Thus, antibodies directed against epitopes in this extracellular domain could have differences in pharmacologic activity between cynomolgus monkeys and human or across individual cynomolgus monkeys. 相似文献