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Twenty-three patients (16 adults) failing their first or subsequent (n = 8) intensive treatment for de novo acute lymphoblastic leukemia (ALL) and chronic myeloid leukemia lymphoid blast phase (n = 2) were managed with protocol POG 8201, originally introduced in relapsed ALL of childhood. In this programme, a four-drug induction phase is followed by early consolidation with teniposide-cytarabine, intrathecal chemotherapy, continuation weekly chemotherapy alternating teniposide-cytarabine with vincristine-cyclophosphamide, and periodic reinduction courses. Fourteen adults and five children with ALL achieved a complete response (CR) (86 per cent). The highest response rate (100 per cent) was obtained in 12 patients treated at first relapse after an initial CR of greater than 18 months (p = 0.07). Median duration of CR was 8 months in adults and 11 months in children. A longer than previous one CR (inversion) was obtained in four cases. Four ALL patients were successfully transplanted from a matched sibling after 3-11 months from achievement of CR. Median overall survival in adults with ALL was 11 months, significantly longer than for 40 comparable cases treated intensively but without rotational continuation therapy in previous years (p less than 0.001). This regimen is applicable to adults with relapsed ALL, where prolongation of survival may allow time for effective salvage with bone marrow transplantation.  相似文献   
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Angiotensin converting enzyme inhibitors (ACEI) are believed to protect remnant kidney, but all previous studies used the ligation model which causes severe hypertension, and very few have compared drugs in rats having similar control of blood pressure (BP). We compared rats with uremia obtained by 70% excision of total renal mass, a model which causes mild, late hypertension. Study I compared the effects of enalapril (E), cicletanine (C) and placebo (P) in uremic (U) rats fed a 0.50% (normal-high) Na diet. Study II compared the effects of E, C, P, and guanfacine (G) in U rats fed a diet restricted to 0.25% Na (normal-low). In study I, UP rats developed progressive hypertension (140, 146, 160 and 166 mm Hg at 3, 6, 9 and 12 weeks), proteinuria (240 mg/day at 9 and 12 weeks) which were not affected by E or C. The occurrence of end-stage renal disease (ESRD) led to the sacrifice of all rats after three months. All three groups had similar severe renal lesions (over 25% sclerosed glomeruli in 5 of 10 UP, 9 of 14 UE, 7 of 14 UC rats, with huge cystic tubular dilatations). In study II, rats could be sacrificed later (6 months) and had evidence of less severe renal disease. All the drugs tested prevented hypertension throughout the study (P less than 0.001), with lowest values in UE rats. E and G, but not C, reduced proteinuria. Renal damage was reduced with E and G, but not with C, despite similar BP in C and G rats. Thus, in contrast with what was obtained in the ligation model, ACEI affected neither the BP nor the renal lesions of rats made uremic by renal excision and fed a 0.50% Na diet. Moderate Na restriction improved the consequences of nephron loss and restored the anti-hypertensive effect of drugs. However, these drugs had a different effect on renal preservation: it was dramatic with E, good with G, and undetectable with C.  相似文献   
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Flexible tantalum stents (Strecker) were used as an adjunct to percutaneous transluminal angioplasty (PTA) in the treatment of stenotic arterial or venous limbs of Brescia-Cimino hemodialysis fistulas. The diagnostic procedure was performed using retrograde fistulography. After PTA with unsatisfactory results, stents were placed in 5 patients with significant residual stenoses and poor fistula function. Within the mean follow-up period of 6.4 months (range 3–10 months) all fistulas were functioning. We conclude that Strecker stent is useful in the treatment of stenotic hemodialysis arteriovenous fistulas as an adjunct to PTA.  相似文献   
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The Hemopump Cardiac Assist System is a relatively new intraarterial, axial-flow circulatory assist device that offers temporary left ventricular support to patients in refractory cardiogenic shock, without requiring major surgery for insertion. Use of the Hemopump is associated with a low complication rate. Device-related morbidity is extremely rare. Because the Hemopump is safe for use in community hospitals, the number of patients supported by this device is expected to increase. In this report, we present general guidelines for the care of patients supported by the Hemopump. We describe techniques for the management of afterload reduction, supravalvular dislodgement, device malfunction, ventricular ectopy, intracardiac shunting, and inflow cannula obstruction.  相似文献   
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We have studied the effect of soman intoxication on serum acute phase reactants (APR) levels, and the relationship of the APR and corticosterone concentrations and the immunosuppressive activity of the serum. One day after the injection of 1.8 LD50 soman the concentrations of 2-macroglobulin (2-MG) and 1-acid glycoprotein (AGP) in the serum of antidote protected rats increased 4- and 7-fold, respectively, whereas those of hemopexin (Hx), haptoglobin (Hp) and cysteine protease inhibitor (CPI) were two to three times higher than in the controls. A similar magnitude of increase of serum acute phase reactants levels was observed when 0.3 LD50 soman was administered at 24-h intervals over the 5-day period. The relationship of changes in the APR concentration, corticosterone level and immunosuppressive activity of the serum was also comparable to that observed in the acute phase response to tissue injury.  相似文献   
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Adrenocorticotrophic hormone (ACTH) is essential for developmental maturation of numerous organ systems during the fetal period and for adaptation to environmental challenges. Immunocytochemical and stereological methods were used in the present study to examine the effects of dexamethasone (Dx) administration during pregnancy on fetal rat pituitary ACTH-producing cells. Doses of 0.5, 0.5 and 1.0 mg Dx/kg body weight/day were given to the dams on 3 consecutive days starting on day 16 of gestation. Morphometric analysis of the ACTH-producing cells of fetuses at 21 days of gestation revealed significant inhibition by 24% and 27%, respectively, of cell volume and cell number after maternal Dx administration, whereas the volume of cell nuclei and volume density of ACTH-stained cells were insignificantly decreased. Immunocytochemical analysis showed reduced numbers, sizes and immunopositivity of ACTH cells of 21-day-old fetuses from Dx-treated dams as compared with the control group. Maternal Dx treatment in the period of intense differentiation of the hypothalamo-hypophyseal-adrenal system had an inhibitory effect on fetal function and proliferative activity of ACTH-producing cells at 21 days of gestation. Thus, inhibition of activity of fetal ACTH-producing cells may lead to adrenal suppression, modified activity of the hypothalamo-pituitary-adrenal axis and reduced body weight possibly causing lasting functional abnormalities.  相似文献   
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