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排序方式: 共有435条查询结果,搜索用时 31 毫秒
101.
MB Koivisto F Eschricht C Urhausen HO Hoppen M Beyerbach CHY Oei AR Günzel-Apel 《Reproduction in domestic animals》2009,44(S2):320-325
Effects of a short-term hyper- and hypoprolactinaemia on serum concentrations of LH, testosterone and semen quality in six male Beagles were investigated. Blood samples were collected at 3-day intervals for 12 weeks. The time span was divided into five 3-week periods: pre-treatment, metoclopramide (MCP) treatment (0.2 mg/kg orally three times daily), cabergoline (CAB) treatment (5 μg/kg orally once daily), post-treatment 1 and post-treatment 2. In the latter, only semen characteristics were evaluated. Semen parameters were analyzed once per week during the whole 15-week investigation time. At the end of each period, the effects of a single intravenous injection of thyrotropin-releasing hormone (TRH; 10 μg/kg) on the secretion of prolactin (PRL), LH, testosterone, thyroid-stimulating hormone and thyroxine (T4) were investigated. Pre-treatment serum PRL concentration increased under MCP (p < 0.05), followed by a decrease under CAB administration (p < 0.05). Luteinizing hormone and testosterone concentrations were not affected. Except for straight-line sperm velocity, semen quality did not differ between collection periods. A single iv TRH injection induced a significant PRL increase at 20 min in all experimental periods except during CAB treatment. Luteinizing hormone and testosterone did not show clear TRH-related changes. Basic T4 levels were significantly reduced after CAB treatment (p < 0.05). The results of the present study demonstrate that MCP-induced short-term hyperprolactinaemia in male beagles does not seriously affect the hypothalamo-pituitary axis and semen quality. 相似文献
102.
103.
Antioxidant profile of cataractous English Cocker Spaniels 总被引:2,自引:1,他引:1
Barros PS Angelotti AC Nobre F Morales A Fantoni DT Barros SB 《Veterinary ophthalmology》1999,2(2):83-86
Cataracts have been attributed to oxidative injury in proteins and lipids. Primary defenses that directly protect the lens against oxidative damage include small molecule antioxidants (vitamin C, vitamin E, glutathione and carotenoids) and antioxidant enzymes (superoxide dismutase, catalase, and the glutathione enzyme systems – glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase). In humans, low plasmatic levels of vitamin C, vitamin E and carotenoids have been associated with a high risk of senile cataracts. Dogs are more prone to develop cataracts. A decrease in antioxidant defenses could be responsible for increased lens oxidation and cataract development. In this study we report the levels of erythrocytic enzymatic antioxidants (superoxide dismutase, catalase, glutathione peroxidase and glucose-6-phosphate dehydrogenase) and plasma vitamin C as well as malondialdehyde, in normal and cataractous English Cocker Spaniel dogs. Plasma vitamin C levels were consistently lower in cataractous dogs (20.17 μ m ± 8.2 μ m ) when compared with normal dogs (24.1 μ m ± 9.4 μ m ). These results indicate a possibly decreased synthesis in vitamin C, leading to lower aqueous humor levels of this vitamin. Considering that vitamin C levels in the aqueous humor may be responsible for lens antioxidant maintenance, and that these levels are obtained from plasma secretion through the ciliary epithelium, decreased plasma levels may indicate a decrease in the antioxidant capacity of the aqueous humor. 相似文献
104.
Macieira Dde B Messick JB Cerqueira Ade M Freire IM Linhares GF Almeida NK Almosny NR 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(1):44-48
BACKGROUND: Infection with Ehrlichia canis causes a highly variable, multisystemic disease in dogs. Nevertheless, many clinicians in Rio de Janeiro, Brazil, use the presence of only thrombocytopenia to make a presumptive diagnosis of E canis infection. OBJECTIVE: The objective of this study was to determine the prevalence of E canis in thrombocytopenic dogs from Rio de Janeiro, Brazil, using polymerase chain reaction (PCR). METHODS: Following DNA extraction of whole blood samples from 226 dogs, PCR assays were done using primers for rickettsial DNA (including Ehrlichia spp, Anaplasma platys and A phagocytophilum) and using E canis-specific primers (16S rRNA gene). Dogs were grouped as thrombocytopenic and nonthrombocytopenic based on platelet counts. The null hypothesis that there was no difference in the prevalence of E canis in these groups was rejected at P<.05. RESULTS: Thirty-six (32.1%) of the thrombocytopenic dogs and 4 (3.5%) of the nonthrombocytopenic dogs were positive for rickettsial gene sequences (P<.0001). Further, 30 (26.8%) of thrombocytopenic dogs and 4 (3.5%) nonthrombocytopenic dogs were positive for E canis-specific gene sequences (P<.0001). CONCLUSIONS: Although the prevalence of E canis infection was higher in thrombocytopenic dogs, less than one third of these dogs had demonstrable E canis infection. Thus, thrombocytopenia is not specific for the detection of E canis infection and should not be used solely to establish a diagnosis of canine ehrlichiosis, even in a geographic area with relatively high disease prevalence. 相似文献
105.
de Souza AI Barros EM Ishikawa E Ilha IM Marin GR Nunes VL 《Veterinary parasitology》2005,128(1-2):41-45
A case of leishmaniasis in a domestic cat (Felis domesticus) is described. The animal showed a single, nodular lesion on the nose and many nodules of different size on the ears and digital regions of all the paws. Diagnosis was made by microscopic detection of amastigotes in Giemsa-stained smears from the lesions. By monoclonal antibodies the aetiological agent was identified as Leishmania (Leishmania) amazonensis, one of the seven species implicated in human leishmaniasis in Brazil. The clinical signs in feline leishmaniasis are unspecific and similar to those observed in other diseases such as cryptococcosis and in sporotrichosis, commonly found in cats. Leishmaniasis should therefore, be added to the differential diagnosis by feline veterinary practitioners and adequate investigations should carried out for dermal leishmaniasis in the area where the feline infection is detected. 相似文献
106.
Schubach TM Schubach A Okamoto T Pellon IV Fialho-Monteiro PC Reis RS Barros MB Andrade-Perez M Wanke B 《The Journal of small animal practice》2003,44(9):395-398
The recovery of Sporothrix schenckii from blood samples is rare, and the diagnosis of systemic sporotrichosis is usually made at necropsy. In this report, S schenckii was isolated from two or more internal organs of nine necropsied cats with naturally acquired sporotrichosis. Haematogenous spread was demonstrated in vivo by the isolation of S schenckii from the peripheral blood of 17 (n = 49, 34.4 per cent) cats. Feline leukaemia virus (FeLV) was not detected, and co-infection with feline immunodeficiency virus (FIV), observed in nine cases (n = 43, 20.9 per cent), apparently did not affect the isolation of S schenckii from peripheral blood or from the internal organs. 相似文献
107.
Rachel C. Murray Vet. MB PhD Bridget L. Roberts BVMS Michael C. Schramme Dr. Med. Vet. PhD Sue J. Dyson Vet. MB PhD Marion Branch BSc 《Veterinary radiology & ultrasound》2004,45(2):103-111
Injury of the distal aspect of the deep digital flexor tendon (DDFT) is a recognized cause of lameness, but diagnosis is difficult. This study aimed to improve understanding of DDFT morphology and pathology using retrospective evaluation of magnetic resonance (MR) images. We hypothesized that: (1) The distal aspect of the DDFT in normal horses would have a repeatable proximal/distal pattern and symmetry between limbs and between lobes; (2) DDFT dimensions would be related to bodyweight, navicular bone dimensions and hoof size; (3) this symmetry and pattern would be lost in DDFT injury; and (4) DDFT size would increase with injury. MR images of 64 live horse limbs, 26 with no identified DDFT lesion and 38 with identified DDFT abnormalities, and 19 normal cadaver limbs were analyzed. Using standardized transverse images, measurements of DDFT cross-sectional area, medial-lateral (ML) width and dorsal-palmar depth were obtained at six preselected sites. A uniform distal to proximal shape pattern was identified in all horses. The flattened crescent shape at the insertion changed to a deeper bilobed shape more proximally, with the mid-navicular area having the greatest cross-sectional area. Strong ML (P < 0.0006) and left/right symmetry (P < 0.02) were observed. In addition, there was a strong association between DDFT cross-sectional area and horse weight (P = 0.005) and between DDFT and navicular bone ML width (P = 0.004). Symmetry between sides or between lobes was lost at sites with a unilateral lesion and correlation between horse weight and DDFT cross-sectional area was lost in the presence of lesions. DDFTs with core lesions had a consistent increase in cross-sectional area overall, but other lesion types had no significant increase in size. The shape and symmetry seen in normal tendons could be related to the mechanical demands placed upon individual lobes. The limited increase in cross-sectional area with injury may be explained by the restrictive structures of the hoof, possibly explaining the ongoing pain seen in such lesions. 相似文献
108.
Moraes PT Pacheco MR de Souza WM da Silva RA Neto PB Barreto CS Ribeiro AA 《Anatomia, histologia, embryologia》2002,31(6):362-366
The digestive system of the capybara has been investigated because of its coprofagia habits, important for their absorptive activity. These species present differences in terms of gastrointestinal morphological characters when compared with other rodents. Macroscopiclly, the stomach of the capybara is constituted of the following parts: cardiac, pyloric, body, fundic and gastric diverticulum. It presents two curvatures, one big and another small. Externally, the presence of gastric bands (tenias) is observed. With regards to the volumetric view, the gastric capacity varies from 850 to 2010 ml, with an average of 1498.57 ml. So, the stomach of this animal can be classified as a simple stomach, in the format of a curved sack and similar to an inverted letter 'J'. The gastric mucous membrane presents a surface filled by numerous tortuous gastric folds and longitudinally distributed along all its extension. The mucous tunic also possesses recesses located among the successive gastric folds, which were denoted as gastric parts with numerous openings described as gastric pits. In the cardiac part, a glandular epithelium with cardiac glands is noticed containing a lot of parietal and mucous neck cells. The fundic part, body and gastric diverticulum contain proper gastric glands with main, parietal and mucous neck cells. Finally, the pyloric part has pyloric glands with two cellular types, mucous neck and parietal cells. 相似文献
109.
ROLFE M. RADCLIFFE DVM Diplomate ACVS JON CHEETHAM Vet MB Diplomate ACVS ABRAHAM J. BEZUIDENHOUT BVSc DVSc NORM G. DUCHARME DVM MS Diplomate ACVS ALAN J. NIXON BVSC MS Diplomate ACVS 《Veterinary surgery : VS》2008,37(8):733-740
Objective— To describe anatomic considerations and arthroscopic technique in horses for arthroscopic removal of palmar/plantar osteochondral fragments from the proximal interphalangeal (PIP) joint. Study Design— Retrospective study. Animals— Adult horses (n=4) with osteochondral fragments of the palmar/plantar PIP joint. Methods— Arthroscopic removal of palmar/plantar osteochondral fragments within the PIP joint was performed with horses in dorsal recumbency under general anesthesia. Medical records of affected horses were reviewed to determine history; physical, lameness, and radiological findings; surgical technique; complications and outcome. Results— Two horses had lameness localized to the PIP joint. Two other horses had lameness suspected, but not confirmed to the pastern region. One of these horses had a history of intermittent lameness, but was not lame on admission. All horses had radiographic evidence of palmar/plantar osteochondral fragmentation within the PIP joint. Fragmentation was located abaxially in 2 horses in the hind limb and axially in 2 horses in the left forelimb. Osteochondral fragments were successfully removed via a palmar/plantar arthroscopic approach in all horses. Three horses returned to previous levels of athletic performance; 1 horse was used for trail riding instead of reining. Conclusions— Arthroscopy of the palmar/plantar pouch of the PIP joint allowed limited assessment of the joint and removal of osteochondral fragments. Clinical Relevance— Arthroscopy of the palmar/plantar PIP joint pouch for assessment and removal of osteochondral fragments is possible and should be considered when lameness is localized to this joint. 相似文献
110.
Barros Lílian Moreira Prochnow Daiane de Oliveira Victoria Freitas da Silva Airton Rosa de Oliveira Antonio Costa da Maia Luciano Carlos 《Journal of Crop Science and Biotechnology》2019,22(1):31-36
Journal of Crop Science and Biotechnology - The morphological characterization allows one to estimate and evaluate the genetic distance among different varieties, identifying heterotrophic groups... 相似文献