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11.
15 patients with acute myeloid leukaemia (AML) were treated with low-dose cytosine arabinoside (LD ARA-C). 2 patients had complete remissions, which lasted for 8 and 3 months, and 5 patients had a partial remission. 46% of the patients thus responded to LD ARA-C. This included 1 responding patient who had not previously responded to therapy with 6-mercaptopurine, thioguanine, or vinblastine. The 2 patients with complete remission did not show LD ARA-C-induced hypoplasia of bone marrow, although 1 had hypoplastic AML before therapy. Leukaemic cells from 1 patient showed in vivo maturation from M1 to M3 after LD ARA-C treatment. The present results, together with the published data, indicate that: a. LD ARA-C treatment, although it may have some toxic effects, is an effective treatment for some patients with AML, especially those with hypoplastic AML; b. Response to LD ARA-C can be obtained after one or several courses of treatment; c. LD ARA-C-induced remissions are sometimes obtained even in patients who fail in more conventional treatments; d. LD ARA-C-induced remissions can be achieved without bone marrow hypoplasia, and induction of hypoplasia by itself does not always result in complete remission; e. LD ARA-C can induce in vivo maturation of leukaemic cells. It is suggested that induction of remission in AML patients by LD ARA-C may result from either differentiation of leukaemic blast cells, cytotoxicity to leukaemic blasts, or both mechanisms acting together.  相似文献   
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The pathogenesis of late renal allograft loss is heterogeneous and difficult to diagnose. We have analyzed renal allografts in nonhuman primates to determine the relationship between alloantibodies and the graft pathology of late graft loss. Seventeen Cynomolgus monkeys were chosen from among those on several protocols for renal allotransplantation with mixed chimerism induction so that animals with and without alloantibodies were included. All animals received transient CD154 blockade and short-term cyclosporine treatment until day 28. Serial blood samples were tested for alloantibodies. Protocol biopsies and autopsy kidneys were scored for pathology and C4d deposition. Group 1, defined by complete lack of C4d deposition (24 tissue samples; 8 recipients), had no detectable alloantibodies (33 serum samples; 1-7 samples per recipient) and no evidence of chronic rejection. Three survived greater than 2 years with normal function and histology. Group 2, defined as having C4d deposition in peritubular capillaries, all made alloantibodies (100%), and most grafts later showed chronic allograft glomerulopathy (89%), and/or arteriopathy (89%). All grafts in Group 2 failed (3-27 months). Pathologic lesions of typical of chronic rejection in humans develop in monkeys, correlate with antecedent alloantibodies/C4d deposition and predict chronic rejection rather than durable accommodation.  相似文献   
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Of 1,470 patients treated with neuroleptics during 1 year at a private psychiatric hospital, only one patient developed neuroleptic malignant syndrome--an annual frequency of 0.07%. Use of low doses of neuroleptics may account for this frequency, which is below recent estimates.  相似文献   
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Endothelin-1 in children with chronic renal failure   总被引:1,自引:0,他引:1  
Endothelin-1 (ET-1) was meansured after extraction from plasma of normal adults (5.9±1.9 pg/ml,n=22), normal children (7.1±1.86 pg/ml,n=29), nonhaemodialysed children with chronic renal failure (CRF) (11.1±1.8 pg/ml),n=10), renal graft recipients (9.5±3.4 pg/ml,n=37), haemodialysed children 24 h after a haemodialysis session (20.02±10.9 pg/ml,n=26) and haemodialysed children before and after a haemodialysis session (15.31±10.6 and 13.8±8.5 respectively,n=14). A sensitive and specific radioimmunoassay was used. ET-1 was significantly higher in non-haemodialysed CRF children and in renal graft recipients than in normal children (P<0.001 andP<0.01, respectively) and significantly higher in haemodialysed children when compared with normal children, non-haemodialysed CRF children and renal graft recipients (P<0.001). ET-1 concentrations were similar in normal children and normal adults. ET-1 was inversely correlated with glomerular filtration rate in non-haemodialysed CRF children (r=–0.39,P<0.01) and positively correlated with extracellular volume in haemodialysed children (r=0.435,P<0.03). After haemodialysis, ET-1 increased in 6 and decreased in 8 of the 14 children studied before and after a haemodialysis session.  相似文献   
16.
The involvement of arachidonic acid (AA) and its metabolites in the control of PTH secretion by porcine parathyroid cells was investigated. Increasing the extracellular calcium concentration from 0.5 to 2 mM increased free [3H]AA release and decreased PTH secretion from labeled parathyroid cells as a function of time (1-30 min). Free [3H]AA in the medium was significantly increased (+153 +/- 6%) after 5 min, while PTH secretion was significantly decreased (-75 +/- 7%) only after 15 min, suggesting a link between the two. [3H]AA release was associated with a decrease in [3H]AA incorporated into phosphatidylinositol, phosphatidic acid, and phosphatidylcholine, suggesting that these phospholipids are the major source of AA. Exogenous phospholipase-A2 (PL-A2; 1-500 mU/ml) and AA (5-40 microM) inhibited PTH secretion in a dose-dependent manner. PTH secretion inhibited by 2 mM Ca2+ was restored by two PL-A2 inhibitors, indomethacin (30 microM) and mepacrine (50 microM). The cyclooxygenase pathway inhibitor ibuprofen (20 microM) did not restore PTH secretion of affect high Ca(2+)-, AA-, or PL-A2-inhibited PTH secretion. Two inhibitors of the lipoxygenase pathway (LO), phenidone (1 microM) and baicalein (0.1 microM), a relatively selective 12-LO inhibitor, blunted high Ca(2+)-induced inhibition of PTH secretion (+101 +/- 10% and +105 +/- 6%, respectively), but nordihydroguaiaretic acid, which inhibits the 5-LO pathway, did not restore PTH secretion inhibited by high Ca2+, AA, or PL-A2. These results suggested that AA and agents that cause its liberation inhibit PTH secretion. AA may act via the 12-LO, but not via the 5-LO or cyclooxygenase, pathway. Thus, 12-LO products may be second messengers in parathyroid cells.  相似文献   
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Ohne ZusammenfassungVgl. dies. Arch. XXII. Bd. S. 155. 1886, sowie die dazu gehörige Tafel IV, Fig. 8–13.  相似文献   
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In this study we retrospectively examined the results of surgery for atherosclerotic renal artery lesions and analysed the factors that may affect postoperative blood pressure response, changes in renal function and late mortality. A total of 326 patients were operated on over a 15 year period and were followed up for periods from 4 to 165 months (mean follow-up time: 37.2 months). An extra renal vascular area was also involved in 91.4% of cases and in 187 (57.3%) a significant involvement of both renal arteries was found and simultaneously treated. Combined revascularisation of other arteries was performed in 50.3% of patients. The indications for surgery were the treatment of extreme hypertension in 243 patients (74.5%), the improvement of renal function in 45 with renal insufficiency, and preservation of the kidney in 38 (11.7%). The preferred method of reconstruction was transaortic endarterectomy (236 cases, i.e. 72.4%) and postoperative angiography demonstrated a normal patent renal artery in 319 of 338 studied renal arteries (94.4%). There were no deaths in the early postoperative period after isolated renal artery reconstruction. Of the 164 patients with simultaneous renal and aortic reconstruction however 14 died during the early postoperative phase. The overall early mortality was thus 4.3% (14 out of 326 patients) and correlated significantly with the extent of the atherosclerotic disease, the age of the patients, the operative technique used and the different intra- and postoperative management during the two different periods of our experience (1974-1980 v. 1981-1989).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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