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21.
22.
Between 1969 and 1993, 123 patients were accepted in this unit for surgery for refractory hyperparathyroidism associated with chronic renal failure. Subtotal parathyroidectomy was the procedure of choice. At operation, four or more parathyroids were identified in 75% of patients. Methylene blue localised additional parathyroids in 32% of initial explorations in which it was used. Coincidental thyroid pathology was found in 8.3%, including papillary carcinoma in 2.4%. No further parathyroid surgery was required in 90% of patients at a mean of 6.6 years after operation. Reoperation (10%) was more likely to be required (14.3%) when less than four glands were found than when four or more were found (8.5%). Patients continuing on dialysis were more likely to need reoperation than those with functioning renal transplants. 相似文献
23.
Gel filtration chromatography and SDS-PAGE of venom from two specimens of Demansia psammophis showed little similarity. Amidolytic activity of the venoms, however, was in the same order of reactivity against various chromogenic substrates. The venom from both snakes produced precipitin lines with brown snake antivenom but the venom detection kit (Commonwealth Serum Laboratories) identified one venom as brown snake (Pseudonaja sp.) and the other as tiger snake (Notechis sp.). These results raise questions about the phylogeny of this species. 相似文献
24.
Effect of ciprofibrate, bezafibrate, and LY171883 on peroxisomal beta-oxidation in cultured rat, dog, and rhesus monkey hepatocytes 总被引:3,自引:0,他引:3
P S Foxworthy S L White D M Hoover P I Eacho 《Toxicology and applied pharmacology》1990,104(3):386-394
Cultured rat hepatocytes have been used extensively to study the mechanisms of chemically induced peroxisome proliferation. Hepatocytes from nonrodent species have been used on a limited scale to study interspecies differences in the response. Because of their importance in pharmaceutical safety assessment, we have developed a model to study the response of beagle dog and rhesus monkey hepatocytes to peroxisome proliferators. Treatment of the hepatocytes with peroxisome proliferators was begun after 20 hr in culture and continued for 72 hr. Untreated rat, dog, and monkey hepatocytes retained 62, 42, and 43% of their initial (20 hr) peroxisomal beta-oxidation activity throughout 92 hr of culture. Ciprofibrate, bezafibrate, and LY171883 caused a dose-related increase in beta-oxidation in rat hepatocytes to a maximum of 10-, 8-, and 5-fold, respectively. In dog and monkey hepatocytes the increases in beta-oxidation were less than 2-fold. Peroxisome morphology in dog and monkey hepatocytes appeared to be unchanged by the drugs. Morphometric analysis in monkey hepatocytes showed no increase in peroxisome volume fraction in response to the chemicals. Treatment of dog and monkey hepatocytes with dexamethasone and glucagon during the final 24 hr in culture caused a 4- to 6-fold increase in tyrosine aminotransferase activity. This induction is characteristic of the in vivo response. The small increase in beta-oxidation reflects the relative insensitivity of the dog and monkey liver to peroxisome proliferators in vivo rather than a loss of sensitivity during culture. Cultured hepatocytes from beagle dog and rhesus monkey may provide a model for studying the mechanisms underlying the interspecies differences. Such information would help clarify the relevance of rodent data in human risk assessment. 相似文献
25.
The flow cytometric crossmatch and early renal transplant loss 总被引:3,自引:0,他引:3
R J Mahoney K A Ault S R Given R J Adams A C Breggia P A Paris G E Palomaki S A Hitchcox B W White J Himmelfarb 《Transplantation》1990,49(3):527-535
Data from this retrospective study indicate that a positive two-color T and/or B cell flow cytometric crossmatch (FCXM) is predictive of early renal allograft loss (less than 2 months) in cadaveric kidney donor recipients who had a negative crossmatch by the antihuman globulin complement-dependent cytotoxicity technique. Among 90 cadaveric kidney donor recipients (67 primary, 23 regrafts), 14 (8 primary, 6 regrafts) lost their renal allografts within 2 months, and 10 of the 14 were FCXM positive and HLA sensitized. The remaining 76 allografts survived beyond 2 months, 12 of which were FCXM-positive. Thus, the FCXM sensitivity rate for detecting early graft loss was 71%, and the specificity rate was 84%. Cadaveric graft-loss rates at 2 months were 33% for primary and 60% for FCXM-positive regrafts in contrast to 7% for primary and 0% for FCXM-negative regrafts. The difference in early graft loss between FCXM-positive and FCXM-negative recipients was statistically significant (P less than 0.0001). Subset analyses of FCXM-positive graft recipients indicate: (1) previous early graft loss contraindicates transplantation of an FXCM-positive regraft (P = 0.03); and (2) panel reactive antibody (PRA) less than or equal to 10% at crossmatch is not associated with early graft loss (P = 0.04). There was no significant difference in 1-year graft survival between primary and regrafts in either FCXM-negative recipients (85% vs. 77%, respectively) or FCXM-positive recipients (67% vs. 40%). All 12 of the FCXM-positive primary and regrafts that survived 2 months continued to function at 2 years. Stepwise logistic regression analysis of 5 independent predictor variables (FCXM status, gender, primary vs. regraft status, PRA level, and HLA mismatched antigens) indicated that the FCXM test was the best predictor of early graft loss. When FCXM results of the 90 cadaveric graft recipients were ranked in three groups, an FCXM channel shift of 29 or greater (third tertile) on a 1024 channel log scale was associated with a 7.0-fold (95% confidence interval 1.9-25.5) increased risk of early graft failure when compared to the first two tertiles. These data indicate that the FCXM offers an additional approach for identifying sensitized patients at risk of early renal allograft loss. 相似文献
26.
Hydroxyethyl methacrylate (HEMA) has been advocated as a polymerizing solution with which to prevent deflation of detachable balloons in interventional neuroradiology. It is pertinent to know if unpolymerized HEMA would have untoward effects if accidentally released into the carotid artery by balloon rupture or deflation. Seven mongrel dogs underwent transfemoral catheterization of the common carotid artery and subsequent injection of HEMA solution in volumes of 1 cc in five dogs, 2 cc in one, and 4 cc in one. Angiography performed at the time of injection revealed evidence of intravascular thrombosis as well as possible spasm. Three surviving animals were sacrificed at 48 hours; the brains were fixed and examined histopathologically. One brain was normal and one was autolyzed and could not be examined. Five of the seven animals had histopathologically documented cerebral infarctions of varying size. No foreign substance was seen within the blood vessels to suggest intravascular polymerization. The animals injected with 2 or 4 cc HEMA solution did not survive 48 hours. Literature review reveals little documentation of the toxicology of intravascular HEMA. With its increasing popularity as a compound for polymerization in detachable balloons introduced into the brain, further investigations are warranted to understand the physical properties of the compound and potential risks of its use. 相似文献
27.
Testicular involvement in acute lymphocytic leukemia is considered an indicator of extramedullary relapse following chemotherapy. Biopsy of the testes prior to the cessation of chemotherapy has yielded early diagnosis and treatment of relapse, with an improved prognosis. Scrotal ultrasonography successfully guided the biopsy of palpably normal testes in a boy with acute lymphocytic leukemia. This success suggests that ultrasound may be a useful adjunct in localizing occult testicular leukemia prior to biopsy. 相似文献
28.
A D Deitch V A Andreotti M A Strand L Howell R W deVere White 《The Journal of urology》1990,143(4):700-705
We describe a method to fix exfoliated bladder cells that is suitable for followup of bladder cancer patients by deoxyribonucleic acid flow cytometry. After fixation with room temperature methanol plus acetic acid (20:1, volume:volume) urine and bladder washing samples from these patients can be stored at room temperature for 3 to 7 days and then assessed reliably for the presence of aneuploidy and the percentage of hyperdiploid cells. For those with active transitional cell carcinoma diagnostic accuracy comparing fresh to fixed specimens was improved from 58 to 92% with urine and from 50 to 100% with washing samples. For patients with a history of transitional cell carcinoma who currently are free of disease the false positive rate remains unchanged after fixation. The procedure described is suitable for use in the outpatient clinic and should permit shipping of samples without refrigeration to a central flow cytometry facility for analysis. 相似文献
29.
30.
W B Greene L T DeGnore G C White 《The Journal of bone and joint surgery. American volume》1990,72(1):2-11
Thirty patients who had hemophilia and were seropositive for the human immunodeficiency virus were evaluated. The preoperative CD4 lymphocyte count was decreased to an average of 336 x 10(9) per liter (range, 27 to 708 x 10(9) per liter). After twenty-six orthopaedic operations in patients who had no previous bacterial infection, a nosocomial infection (cellulitis in the forearm, at the site of an intravenous catheter) developed in only one patient, but five patients had an abnormal postoperative fever that was not accompanied by the expected increase in the white blood-cell count. The preoperative CD4 lymphocyte count was significantly reduced in the patients who had an abnormal elevation in body temperature (p less than 0.004). The functional result or outcome after operation was similar to that in hemophilic patients treated before 1982. Subsequent progression of infection with the human immunodeficiency virus, as determined by the CD4 lymphocyte count and the Walter Reed classification system, occurred in most patients. Acquired immunodeficiency syndrome was diagnosed in six patients. A more rapid progression to acquired immunodeficiency syndrome was seen in the patients who had a lower CD4 lymphocyte count preoperatively. Preoperative evaluation of the CD4 lymphocyte count and the response to intradermal skin-test antigens in patients who are at risk for infection postoperatively provides additional information concerning immunological competence. With these data, the possible risk of infection in patients who are seropositive for the human immunodeficiency virus can be estimated more accurately. 相似文献