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51.
Two months after colic surgery, subcutaneous masses were found on the ventral and lateral portions of the thorax of a 3-year-old Hanoverian-cross filly. Six months later, the filly was admitted for evaluation of severe lameness. Arthrocentesis of the tarsocrural joint yielded clotted sanguineous material; however, unusual multinucleated giant cells were seen. Radiography of the right tarsus revealed soft tissue opacity and degenerative joint disease. The filly was euthanatized to prevent further suffering. At necropsy, multiple soft-tissue masses were located throughout the fascial planes of the tarsi and in the subcutis of the ventral and lateral portions of the thorax. Neoplasms consisted primarily of a large number of mature well-differentiated T lymphocytes. On the basis of these findings, the diagnosis was cutaneous lymphoma with unusual involvement of periarticular tissues. Severe degenerative joint disease in the right tarsus did not appear to be associated with the tumors. 相似文献
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An important component of barrier function in human epidermis is contributed by ceramides that are bound by ester linkages to undefined proteins of the cornified cell envelope (CE). In this paper, we have examined the protein targets for the ceramide attachment. By partial saponification of isolated foreskin epidermal CEs followed by limited proteolysis, we have recovered several lipopeptides. Biochemical and mass spectroscopic characterization revealed that all contained near stoichiometric amounts of ceramides of masses ranging from about 690 to 890 atomic mass units, of which six quantitatively major species were common. The array of ceramides was similar to that obtained from pig skin, the composition of which is known, thereby providing strong indirect data for their fatty acid and sphingosine compositions. The recovered peptides accounted for about 20% of the total foreskin CE ceramides. By amino acid sequencing, about 35% of the peptides were derived from ancestral glutamine-glutamate-rich regions of involucrin, an important CE structural protein. Another 18% derived from rod domain sequences of periplakin and envoplakin, which are also known or suspected CE proteins. Other peptides were too short for unequivocal identification. Together, these data indicate that involucrin, envoplakin, periplakin, and possibly other structural proteins serve as substrates for the attachment of ceramides by ester linkages to the CE for barrier function in human epidermis. 相似文献
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AG Magee BW McCrindle J Mawson LN Benson WG Williams RM Freedom 《Canadian Metallurgical Quarterly》1998,32(2):502-508
OBJECTIVES: To determine the prevalence of systemic venous collaterals after the bidirectional cavopulmonary anastomosis and the factors associated with their development. BACKGROUND: Systemic venous collaterals have been found after cavopulmonary anastomosis. Methods. Cardiac catheterization was performed in 103 patients before and after a bidirectional cavopulmonary anastomosis. RESULTS: After surgery, 51 venous collaterals were identified in 32 patients (31%). Collateral development was associated with an abnormal superior vena caval connection (56% incidence vs. 26% with a single right superior vena cava, p = 0.01) and postoperative factors including pulmonary artery distortion (53% incidence vs. 22% without distortion, p = 0.002); increased superior vena caval mean pressure (14 +/- 5 mm Hg versus 11 +/- 4 mm Hg with no collaterals, p = 0.0002); increased pulmonary artery mean pressure (13 +/- 4 mm Hg vs. 11 +/- 4 mm Hg with no collaterals, p = 0.02); lower right atrial mean pressure (5 +/- 2 mm Hg vs. 6 +/- 3 mm Hg with no collaterals, p = 0.04); and increased mean gradient between superior vena cava and right atrium (8 +/- 3 mm Hg vs. 5 +/- 4 mm Hg with no collaterals, p = 0.0002). Using multiple logistic regression, only this last factor was independently associated with collateral development with an odds ratio per 1 mm Hg of 1.33 (95% CI 1.12-1.58, p = 0.001) for their presence. CONCLUSIONS: Systemic venous collaterals occur frequently after a bidirectional cavopulmonary anastomosis and are found postoperatively when a significant pressure gradient occurs between cava and right atrium. 相似文献
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GK Bejjani PC Nora PL Vera L Broemling LN Sekhar 《Canadian Metallurgical Quarterly》1998,43(3):491-8; discussion 498-500
INTRODUCTION: There is some controversy regarding the value of intraoperative neurophysiological monitoring in predicting postoperative neurological deficits. We discuss our experience with the use of intraoperative somatosensory evoked potentials (SSEPs) during surgery of cranial base tumors. METHODS: We retrospectively reviewed all of the procedures that had been performed for the resection of cranial base tumors from July 29, 1993, through March 16, 1995. One hundred ninety-three consecutive patients had undergone a total of 244 procedures. SSEP waveforms were classified as follows: Type I, no change; Type II, change that reverts to baseline; Type III, change that does not revert to baseline; and Type IV, complete flattening of the SSEP waveform without improvement. Two patients had no waveforms from the beginning of the case (Type V) and were excluded from further analysis. New immediate postoperative neurological deficits were recorded. RESULTS: There were 64 male and 129 female patients, with a mean age of 46.6 years. One hundred seventy-seven patients had Type I SSEP waveforms, 13 of whom had postoperative deficits (7%). Fifty-six patients had Type II SSEPs, and nine (16%) of them had postoperative neurological deficits. Six patients had Type III SSEPs, and three had Type IV SSEPs, all of whom (100%) had postoperative deficits. There was a correlation between SSEP type and the results of the postoperative neurological examinations. The positive predictive value is 100%, and the negative predictive value is 90%. Although a change in the waveform that did not revert to baseline (Types III and IV) always predicted a postoperative deficit, a normal waveform did not always rule out postoperative deficits. Pathological abnormality, vessel encasement, vessel narrowing, degree of cavernous sinus involvement, brain stem edema, middle fossa location, final amount of resection, age, and tumor size correlated with a high predictive value of SSEP monitoring on univariate analysis (P < 0.05). None of these variables correlated significantly on multivariate analysis (P > 0.05), although brain stem edema was close (P = 0.0571). CONCLUSION: Intraoperative SSEPs have a high positive predictive value during surgery for cranial base tumors, but they do not detect all postoperative deficits. 相似文献
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S Kumar HA Ashe LN Parnell DJ Fernando C Tsigos RJ Young JD Ward AJ Boulton 《Canadian Metallurgical Quarterly》1994,11(5):480-484
The prevalence of peripheral neuropathy, peripheral vascular disease, and foot ulceration in Type 2 diabetic patients in the community were determined in a community-based study. Eight hundred and eleven subjects (404 male, 407 female, mean age 65.4 (range 34-90) years, diabetes duration 7.4 (0-50) years) from 37 general practices in three UK cities were studied. Neuropathy was diagnosed clinically using modified neuropathy disability scores which were ascertained using structured interviews and clinical examinations by one observer in each city. Peripheral vascular disease was diagnosed if a history of revascularization was present or > or = 2 foot pulses were absent. History of current or previous foot ulceration was recorded. The prevalence of neuropathy was 41.6% (95% confidence limits 38.3-44.9%) and the prevalence of PVD, 11% (9.1-13.7%). Forty-eight percent of neuropathic patients reported significant neuropathic symptoms. Forty-three patients (5.3% (3.8-6.8%)) had current or past foot ulcers; 20 of these were pure neuropathic ulcers, 13 neuroischaemic, 5 pure vascular, and 5 were unclassified. Multiple logistic regression showed history of amputation, neuropathy disability score, and peripheral vascular disease to be significantly associated with foot ulceration after adjusting for age and diabetes duration. A substantial proportion of Type 2 diabetic patients, often elderly patients who do not attend hospitals, suffered from peripheral neuropathy and peripheral vascular disease. These patients are at risk of foot ulceration and may benefit from preventive footcare. 相似文献
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LN Diebel JG Tyburski SA Dulchavsky 《Canadian Metallurgical Quarterly》1998,124(4):642-9; discussion 649-50
BACKGROUND: Hypertonic saline solutions may have beneficial hemodynamic effects in the resuscitation of hemorrhagic shock. The effects on cardiac function and potential interaction with lung function are controversial and served as the basis for this study. METHODS: Domestic swine were resuscitated from hemorrhagic shock with equivalent sodium loads of lactated Ringer's solution (LR) or 7.5% NaCl plus 10% dextran (HSD). Hemodynamic data were obtained at baseline, shock, and after resuscitation. Right ventricular ejection fraction and left ventricular change in pressure with respect to time (dP/dt) were used to index contractility. Regional myocardial blood flow was determined with microspheres. Lung water was determined gravimetrically. RESULTS: There were no differences in the ability to restore hemodynamic parameters with equivalent sodium loads of LR and HSD resuscitation. Right ventricular ejection fraction and left ventricular change in pressure with respect to time were only transiently affected by shock and resuscitation. Regional myocardial blood flow was increased above baseline values after HSD. The total resuscitation volumes were 1958 +/- 750 mL and 140 +/- 31 mL with LR and HSD, respectively. CONCLUSIONS: Although LR and HSD were equally effective in the early resuscitation of hemorrhagic shock, this occurred at the expense of significantly greater volume requirements for resuscitation with LR. This may contribute to cardiac dysfunction in this setting. Enhanced regional myocardial blood flow after HSD resuscitation may be beneficial against ongoing myocardial stress. 相似文献