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31.
Intracranial germ cell tumours were identified in two middle-aged, male dogs. The predominant clinical signs were progressive visual and pupillary abnormalities; one dog was blind. At post mortem examination a discrete extramedullary tumour was found at the base of the brain in each dog. Expansion of the mass had produced severe destruction of the diencephalon and brain stem. Histopathological examination revealed a mixed cellular pattern, consistent with a neoplasm derived from germ cells.  相似文献   
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Certain cytologic features of the porcine adrenal medulla   总被引:1,自引:0,他引:1  
Adrenal glands were collected from pigs of various ages under general anesthesia. Glutaraldehyde-fixed medullary tissue was postfixed with OsO4 for electron microscopy and with potassium dichromate or potassium iodate for light microscopy. Columnar epinephrine (E) cells formed cords between wide sinusoidal capillaries at the corticomedullary junction and were arranged in palisade fashion along the central vein and its major tributaries. The E cells usually were polarized, with the nuclei located away from the sinusoidal capillaries. Clusters of polygonal norepinephrine (NE) cells formed large central aggregates surrounded by E cells. Granulated vesicles were the predominant cytoplasmic feature of both E and NE cells. Round or oval E granules were bounded by a crenated membrane separated from the granule by a clear halo. The more electron-dense, elongate NE granules were bounded by a closely apposed, smooth membrane. The average longest granule axis was 270 nm for E granules and 305 nm for NE granules. Many cytoplasmic organelles were congregated in a granule-free paranuclear zone, which contained a prominent Golgi complex. Thin nonmyelinated nerve fibers (singly or in small groups) were interposed between the E and NE cells. Nerve fibers often were located close to the nucleus in a depression of the cell surface and often were wrapped by thin E or NE cell processes. The medulla of newborn pigs was composed predominantly or exclusively of NE cells. In both adults and pigs, E or NE cell cords radiated through the cortex toward the capsule, and isolated clusters of E or NE cells frequently were found in the capsule or zona glomerulosa.  相似文献   
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Three dogs and 1 cat with intranasal tumors were treated with pyropheophorbide-a-hexyl ether-based photodynamic therapy (PDT). PDT was well tolerated by all the animals, and no adverse effects from photosensitizer injection, such as cutaneous photosensitization, were observed. Facial swelling was observed in all animals after each PDT treatment but resolved spontaneously within 72 hours after treatment. All animals had a decrease in severity of epistaxis, frequency of sneezing, and amount of nasal discharge after PDT. Clinical signs were controlled for variable time, although long-term responses were comparable with radiation therapy in 2 animals. This small case series demonstrates another application for PDT in veterinary medicine. On the basis of these findings. further studies are warranted to define the role of PDT in the management of intranasal tumors in dogs and cats.  相似文献   
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OBJECTIVE: To describe the demographic and clinical characteristics of a population of geriatric horses. DESIGN: Retrospective study. ANIMALS: 467 horses that were > or = 20 years of age. PROCEDURE: Medical records of 539 geriatric horses that were evaluated at a university large animal hospital between 1989 and 1999 were reviewed. Data collected included signalment, reason for evaluation, specific diagnoses, surgical procedures, inpatient or outpatient care, duration of hospitalization, and outcome. RESULTS: 467 horses met the criteria for inclusion in the study. Horses that were > or = 20 years of age comprised 2.2 and 12.5% of horses evaluated during 1989 and 1999, respectively. Pony breeds were significantly overrepresented in the > or = 30-years-of-age group. Gastrointestinal tract, musculoskeletal, and respiratory tract problems were most frequently reported. Colic was the most common clinical sign, followed by lameness. Diagnoses made most frequently included pituitary dysfunction, strangulating lipoma of the small intestine, laminitis, heaves, large colon impaction, and gastric ulcers. Pituitary dysfunction was significantly more prevalent in horses that were > 30 years of age. Laminitis was significantly associated with the presence of pituitary dysfunction. CONCLUSIONS AND CLINICAL RELEVANCE: It was difficult to assess association of age with illnesses identified in these horses. Demographic data and information regarding common diseases of horses that are > or = 20 years of age are limited but will become increasingly important as this geriatric population increases.  相似文献   
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OBJECTIVE: To describe the demographic and clinical characteristics, management practices, and owner perception of a population of geriatric horses, and to compare these data with findings in a group of younger horses. DESIGN: Original study. ANIMALS: 218 horses. PROCEDURE: Data were collected via a survey tool from owners of 165 horses that were > or = 20 years of age and 53 horses that were < 20 years of age. RESULTS: Compared with young horses, the geriatric group included a significantly greater number of ponies; geriatric horses were also more likely to have a history of colic, dental disease, tumors, lameness, and pituitary disease, but not laminitis, diarrhea, allergies, respiratory tract disease, thyroid disease, or fractures. Horses that had participated in Western equestrian disciplines were more likely to have a history of lameness. Among old horses, those with pituitary dysfunction were more likely to have a history of laminitis than those without pituitary dysfunction. Geriatric horses were more likely to have long hair and shedding abnormalities than were younger horses. Owners perceived their horses as old at approximately 22 years of age. In horses older than 16.5 years of age, age was a negative factor in the purchase of horses. CONCLUSIONS AND CLINICAL RELEVANCE: Geriatric and young horses share some similar health problems, but old horses have distinct health problems and veterinary medical requirements. The management and athletic history of horses may influence health as they age.  相似文献   
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A retrospective study was performed describing the clinical presentations, radiographic findings, and surgical outcomes of 17 dogs (18 elbows) following medial coronoidectomy for the treatment of elbow joint incongruity as a sole disease entity. Complete resolution of lameness was achieved in 100% of the cases. The mean radiographic arthrosis grade progressed in 70% of the cases. Results of this study indicate that resolution of clinical lameness may be achieved with medial coronoidectomy in dogs with elbow incongruity; however, progression of degenerative joint disease with unknown, long-term clinical significance can be expected after surgery.  相似文献   
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OBJECTIVE: To determine the effect of finasteride on programmed cell death (apoptosis) of prostatic cells during prostatic involution in dogs with benign prostatic hypertrophy (BPH). ANIMALS: 9 dogs with BPH. PROCEDURE: Dogs were randomly assigned to treatment or control groups. Treatment dogs (n = 5) were administered finasteride (0.1 to 0.5 mg/kg, PO, q 24 h) for 16 weeks, whereas the 4 control dogs were administered an inert compound. Prostatic cells from the prostatic fluid portion of the ejaculate of treatment and control dogs were obtained before and 1, 2, 3, 4, 8, and 16 weeks after initiation of treatment. Cells were concentrated by use of centrifugation. Prostatic cells were examined for indications of apoptosis by use of a terminal deoxyribonucleotidyl transferase-mediated deoxyuracil triphosphate nick-end labeling technique. After receiving the inert compound for 16 weeks, the 4 control dogs were administered finasteride for 16 weeks, and evaluations were repeated. RESULTS: Percentage of apoptotic prostatic cells in ejaculated prostatic fluid of treatment dogs increased significantly (from 9% before treatment to 33, 31, 26, and 27% after 1, 2, 3, and 8 weeks of treatment, respectively). There was no significant change in percentage of apoptotic prostatic cells in the ejaculated prostatic fluid of control dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Finasteride-induced prostatic involution appears to be via apoptosis in dogs with BPH. Finasteride treatment of dogs with BPH causes prostatic involution by apoptosis rather than necrosis.  相似文献   
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