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91.
OBJECTIVE: To confirm in vivo optimal laser energy settings previously determined in vitro for lithotripsy, to develop a technique for Ho:YAG laser lithotripsy, and to evaluate acute and chronic tissue effects of laser lithotripsy. STUDY DESIGN: Prospective, randomized preclinical trial. ANIMALS OR SAMPLE POPULATION: Nineteen intact, adult male dogs. METHODS: Via cystotomy, a single urolith was inserted into the urethra to the level of the base of the os penis to simulate obstruction. Uroliths (calcium oxalate, urate, or magnesium ammonium phosphate) were fragmented by Ho:YAG laser, in contact mode through a 320 micro optic fiber, passed through the operating channel of a 2.8 mm flexible endoscope. The time and total energy to fragmentation were recorded. Dogs were euthanatized immediately after lithotripsy (3 dogs) or at 3 days (7 dogs), and urethral lesions and any stone remnants were evaluated. Urethral integrity was also evaluated in 9 other dogs by endoscopy on day 10; these were also monitored clinically for 30 days. RESULTS: The mean time for adequate fragmentation was 166.7 seconds (range, 47-494.5 seconds). The mean+/-SD energy used was 1418+/-851.2 J. In part 1, 2 dogs were obstructed with urolith fragments at necropsy. Eight dogs had minimal (<30 mg) or no urolith material evident within the urethra. Four dogs had gross focal or circumferential erosion, ulceration, or hemorrhage of the urethral mucosa. Lesions were not associated with the site of laser irradiation in 2 dogs. In dogs observed for 30 days, hematuria, pollakiuria, and stranguria that were observed after lithotripsy, resolved in all affected dogs by day 5. No mucosal lesions were observed by endoscopy and none of the dogs became obstructed. CONCLUSION: Laser lithotripsy with the Ho:YAG laser in contact mode successfully fragmented obstructive uroliths in male dogs. CLINICAL RELEVANCE: Laser lithotripsy may be a clinically relevant technique for treatment of urolithiasis in male dogs; clinical studies to evaluate long-term effects on urethral mucosa and the role of repeat treatment for recurrence are indicated.  相似文献   
92.
A 9-year-old, spayed female, Airedale Terrier was euthanatized and necropsied after a progressive clinical course that included Horner's syndrome of the left eye and unilateral atrophy of the masticatory muscles. Although gross lesions were limited, a polyradiculoneuritis and ganglionitis that was most severe in the trigeminal nerves and ganglia were confirmed histologically. The inflammatory infiltrate consisted predominantly of macrophages and B and T lymphocytes that were phenotypically confirmed by immunostaining. Horner's syndrome was the result of damage to postganglionic sympathetic fibers that were incorporated in segments of the inflamed trigeminal nerve and its ophthalmic branch. Histologically, the character and distribution of the inflammation was similar to previously described syndromes of suspected immune-mediated etiology in humans and animals.  相似文献   
93.
An 8‐year‐old, intact female, mixed‐breed dog presented to the Oklahoma State University Boren Veterinary Medical Teaching Hospital for evaluation of progressive lameness and joint effusion of multiple joints. Physical examination revealed joint effusion of the elbow, hock, and stifle joints bilaterally, enlarged left axillary and right popliteal lymph nodes, a subcutaneous mass over the left elbow, and a subcutaneous mass involving the left second and third mammary glands. Cytologic examination of the mammary mass, enlarged lymph nodes, and joint fluid from most affected joints revealed a monomorphic population of loosely cohesive neoplastic epithelial cells. The patient was humanely euthanized, and subsequent necropsy with histopathologic examination revealed a complex mammary carcinoma with metastases to enlarged lymph nodes, subcutaneous tissue over the left elbow, and the synovium of multiple joints. Immunohistochemical stains were performed and showed diffusely positive pan cytokeratin, CK8/18, and CK19 staining in the neoplastic luminal epithelial cells of the mammary carcinoma, synovium, and lymph nodes, and showed diffusely positive vimentin staining of the myoepithelial cells. Myoepithelial calponin positivity was diffuse in the mammary mass and lymph nodes but minimal in the synovium. Only the mammary mass showed p63 positivity. Metastatic mammary neoplasia is relatively common in dogs; however, metastasis to the synovium has only been reported once previously in the literature. This is the first case utilizing immunohistochemistry for confirmation and characterization of metastases.  相似文献   
94.
Ligand blotting of Pasteurella haemolytica leukotoxin (LKT) susceptible BL3 bovine lymphoma cell membranes with LKT detected two putative receptors with Mr of 95 and 100 kDa, whereas no LKT binding to membrane proteins was detected for LKT non-susceptible human leukemic cells. Anti-bovine CD18 and CD11a/CD18 mAb recognized 95 and 100kDa bands from BL3 cell membranes. CD18 isolated from BL3 cell membranes bound LKT. Pre-incubation of BL3 cells with anti-bovine CD18 or CD11a/CD18 mAb caused partial inhibition of LKT-induced leukolysis. Therefore, we propose that bovine CD18 acts as a species-specific leukocyte receptor for P. haemolytica LKT.  相似文献   
95.
This study was conducted to evaluate the effects of different concentrations of the antioxidant N‐acetyl‐cysteine (NAC) supplemented to the maturation medium on porcine embryo development. Concentrations of NAC and its synthetic derivative, NAC‐amide (NACA) were evaluated for effects on nuclear maturation, fertilization success and embryo development. Concentrations of NAC (0, 0.5, 1.0, 1.5, 2.0, 2.5 and 5.0 mm ) were supplemented to maturing oocytes, and embryo development was analysed at 48 and 144 h post‐fertilization. There were no differences among cleavage rates for any of the treatment groups. Blastocyst formation for 1.5 mm NAC (56.5 ± 9.2%) was higher (p < 0.05) than all other supplementations. There were no differences in nuclear maturation or fertilization or in cleavage rates when comparing 1.5 mm NAC and 1.5 mm NACA supplementation to the control. Blastocyst formation for 1.5 mm NAC (44.4 ± 4.7%) and 1.5 mm NACA (46.2 ± 3.4%) supplementation were higher (p < 0.05) than the control (32.1 ± 6.2%) oocytes. These results indicate that supplementing 1.5 mm of NAC or NACA to the oocyte maturation medium increased the percentage of viable embryos reaching the blastocyst stage of development.  相似文献   
96.
Eclogitic diamond formation at jwaneng: No room for a recycled component   总被引:4,自引:0,他引:4  
Eclogitic diamonds have a large range of delta13C values, whereas peridotitic diamonds do not. Paired delta15N-delta13C-N variations in 40 eclogitic diamonds from the Jwaneng kimberlite in Botswana show that neither the influence of recycled biogenic carbon nor the global and primordial heterogeneity of mantle carbon are likely for the origin of the large delta13C range; the data instead support a fractionation process. It is proposed that carbonatitic mantle melts from which diamonds crystallize undergo different evolutions before diamond precipitation, when percolating through either a peridotite or an eclogite. These different evolutions, reflecting the presence or absence of olivine, can account for their respective delta13C distributions.  相似文献   
97.
98.
The second in this series of clinical reviews on neurological diseases in ruminant livestock in Australia examines toxic disorders associated with plant and microbial toxins as well as the neurological effects of vitamin and mineral deficiencies. The aim of these reviews is to assist in the surveillance of neurological diseases, especially the transmissible spongiform encephalopathies.  相似文献   
99.
We have described the efforts of the Australian administration of the Territory of Papua and New Guinea (TPNG) to establish a veterinary service and viable animal industries. These efforts began with planning before the end of World War II in 1945 and continued until independence in 1975. Whereas pre-war cattle had mostly been used to control grass on plantations, post-war, the objective was to use the country's extensive, unoccupied grasslands for cattle production. During this period, the cattle population increased from 4000 to more than 150,000. The greatest success was achieved in herds with crosses of Bos indicus and Bos taurus owned by expatriates. The only serious disease constraint on production was myiasis due to Chrysomya bezziana, a parasite throughout New Guinea and South-east Asia. Attempts were made to increase the productivity of the indigenous pig population. Success was limited by a failure to manage inadequate nutrition and internal parasites and to fully understand the cultural aspects of pig ownership. Similar problems inhibited chicken production in villages. The serious viral infections of pigs and birds were absent from TPNG, but a border with Indonesian Papua represents a potential route for the incursion of animal diseases exotic to both Papua New Guinea and to Australia.  相似文献   
100.
Corynetoxins, members of the tunicamycin group of antibiotics, produce a severe and frequently fatal neurological disorder in ruminant livestock, and guinea pigs are a useful model to study the pathology and pathogenesis of this disease. The aim of this study was to determine whether tunicamycin produced ocular damage in this species, which could have pharmacotherapeutic and diagnostic value. Four 8-week-old guinea pigs were treated with tunicamycin, and two control animals were given the drug vehicle only. Guinea pigs were injected subcutaneously with 400 μg/kg of tunicamycin, in dimethyl sulphoxide, and killed 48 h post-injection. The eyes were then examined by light microscopy. Immunohistochemistry for rhodopsin was also performed. The principal pathological finding was marked retinal photoreceptor damage, which was characterised by disruption and disorganisation of rods, sometimes progressing to necrosis and separation of the outer segment. The cytoplasm of some rods was focally distended by accumulated, proteinaceous material. Rhodopsin immunopositivity in injured rods was markedly diminished and associated with shrinkage and shortening of the injured rod's outer segment. Ocular pathology, in the form of reproducible and extensive retinal photoreceptor damage, was found in guinea pigs given tunicamycin, extending the range of species found to be susceptible to this toxic injury. The guinea pig could prove to be a good animal model to test potential therapeutic interventions, and as brain lesions are often minimal and liver pathology non-specific in intoxicated ruminants, any spontaneously arising ophthalmic injury found in these species could be diagnostically useful.  相似文献   
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