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The aim of this study was to evaluate the effect of correction of chronic anaemia on the physical performance and the cardiovascular response to effort in children with end-stage renal disease (ESRD) maintained by haemodialysis. Seven patients (mean age 13.9 years) underwent triangular-type treadmill exercise testing before [haemoglobin (Hb) 6.3±0.9 g/dl] and after (Hb 11.2±1.2 g/dl) anaemia correction with recombinant human erythropoietin (rHuEPO). After treatment, the work-load reached, the peak oxygen uptake and average ventilatory anaerobic threshold (VAT) values were significantly increased (P<0.01,P<0.001,P<0.05 respectively). VAT values, expressed as a percentage of normal values, increased from 55.7±16.6% to 82.4±21%. This improvement correlated well with the increase in Hb (r=0.79). Oxygen pulse also increased significantly, when tested after anacmia correction. In conclusion, these data demonstrate that when the anaemia of children with ESRD is corrected with rHuEPO, there is a clear improvement in acrobic work capacity and effort tolerance.  相似文献   
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Cancers of the middle umbilical fold are very infrequent, making up 0.1% to 0.7% of all bladder tumors. This type of tumor affects male subjects in 60% to 75% of cases, in the 5th or 6th decade of life. In more than 90% of all cases, the lesion is a mucosecretory adenocarcinoma developing from embryonic remains within the wall of the bladder and respecting the superficial urothelium of the bladder, which is affected only secondarily, contrary to what occurs in the other adenocarcinomas of the bladder. The pathogenesis remains controversial, especially the role of middle umbilical fold patency and of bladder carcinogens. The diagnosis is most often established late, because of a long clinical latency. It is mainly based on ultrasonography and computed tomography. Explorations of the bladder are useful only at an advanced stage. The prognosis is very poor, survival at 5 years ranging from 6.5% to 25% according to the authors. The treatment is mainly surgical. Only extensive exeresis with partial cystectomy extending to the peri- and supravesical environment, including the peritoneum and the umbilicus, and associated with pelvic lymphadenectomy may give some hope. Chemotherapy and radiation therapy, either alone or complementary, are disappointing. The prognosis may be improved only by an early diagnosis.  相似文献   
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AIMS: The aim of this study was to evaluate the anal manometric changes and the clinical effects after topical application of isosorbide dinitrate (ISDN) in patients with persistent constipation after pull-through surgery for Hirschsprung's disease (HD). METHODS: We studied 3 children (2 males and 1 female), aged 2, 3 and 5 years respectively, who had undergone the Soave-Boley surgical procedure for HD and who suffered from persistent constipation after operation. We performed a pre- and postoperative anorectal manometry study and we applied ISDN paste (1 mg/kg two times daily) in the anal region for three weeks. All patients were followed-up and re-evaluated at 1, 3, and 6 months. RESULTS: All patients showed an improvement of symptoms, with an average of 4 spontaneous evacuations per week. Prior to the topical treatment, the medium pressure was 115.6 mmHg (range 102 - 130 mmHg), the maximum pressure was 160 mmHg (range 145 - 175 mmHg), and the medium length of the high pressure zone was 1.8 cm (range 1.5 - 2.0 cm). At the 6 month follow-up, the medium pressure was 57.3 mmHg (range 52 - 61 mmHg, a decrease of 54.4 %), the maximum pressure was 98 mmHg (range 88 - 107 mmHg; a decrease of 38.7 %), and the medium length of the high pressure zone was 1.6 cm (range 1.4 - 1.8 cm; a decrease of 11.1 %). CONCLUSIONS: Topical treatment with ISDN is a valid therapeutic alternative to an anal myotomy in patients with persistent constipation after pull-through surgery for HD. However, a greater number of cases and a longer follow-up are necessary to confirm the validity of our experience.  相似文献   
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Long-term acetyl-L-carnitine (ALCAR) administration prevents the development of escape deficit produced by acute exposure to unavoidable stress. However, it does not revert the escape deficit sustained by chronic stress exposure. Rats exposed to chronic stress show a low dopamine (DA) output in the nucleus accumbens shell (NAcS) and do not acquire an appetitive behavior sustained by the earning of vanilla sugar (VS) made contingent on the choice of one of the two divergent arms of a Y-maze (VS-sustained appetitive behavior, VAB), while control rats consistently do. The present study shows that ALCAR treatment in rats exposed to a 7-day stress protocol prevented a decrease in DA output in the NAcS and medial prefrontal cortex (mPFC) of rats, and that it strengthened the DA response to VS consummation in the same two areas. Moreover, rats treated with long-term ALCAR or exposed to chronic stress while treated with ALCAR acquired VAB as efficiently as control rats. Moreover, VAB acquisition in stressed rats treated with ALCAR coincided with the reversal of the deficits in escape and in dopaminergic transmission in the NAcS. Thus, repeated ALCAR treatment preserved the DA response to VS in chronically stressed rats and this effect appeared to be predictive of the rat's competence to acquire VAB.  相似文献   
8.
Cutaneous T-cell lymphoma   总被引:1,自引:0,他引:1  
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To more nearly accurately quantitate the dose of pharmacologic agents delivered to human and animal airways via aerosols, we have developed a monodisperse aerosol containing either methacholine or histamine that permits a light scattering device (tyndallometry) to measure accurately the quantity of inspired and expired particles. These aerosols (described in previous studies) are simultaneously tagged with a radioactive label (technetium 99m) to permit the use of external gamma camera imaging. Present work focuses on the development of assay techniques to measure the quantity of methacholine delivered in these aerosols. The lack of specific radioimmune or radioenzyme assays coupled with the cross-reaction of organic contaminants with conventional chemical reagents for measuring methacholine required the development of separative techniques to isolate the methacholine from the organic aerosol contaminants. With aqueous extraction and column separation we have been able to completely isolate the methacholine from these contaminants. This allows the application of standard spectrophotometric assays for methacholine to quantitate the methacholine in the resulting solution. These separative techniques will permit the use of these aerosols in quantitative studies of airway reactivity.  相似文献   
10.
Susceptibilities to macrolides were evaluated in 267 Streptococcus pneumoniae isolates, of which 182 were from patients with invasive diseases and 85 were from healthy carriers. Of the 98 resistant isolates, 20 strains showed an M phenotype and carried mef. Strains that carried both mef(A) and mef(E) were found: 17 strains carried mef(A) and 3 carried mef(E). The characteristics of the strains carrying the mef genes and the properties of the mef-containing elements were studied. Strains carrying mef(A) belonged to serotype 14, were susceptible to all the antibiotics tested except erythromycin, and appeared to be clonally related by pulsed-field gel electrophoresis (PFGE). The three mef(E) strains belonged to different serotypes, showed different susceptibility profiles, and did not appear to be related by PFGE. The sequences of a fragment of the mef-containing element, which encompassed mef and the msr(A) homolog, were identical among the three mef(E)-positive strains and among the three mef(A)-positive strains, although there were differences between the sequences for the two variants at 168 positions. In all mef(A)-positive strains, the mef element was inserted in celB, which led to impairment of the competence of the strains. In line with insertion of the mef(E) element at a different site, the competence of the mef(E)-positive strains was maintained. Transfer of erythromycin resistance by conjugation was obtained from two of three mef(A) strains but from none of three mef(E) strains. Due to the important different characteristics of the strains carrying mef(A) or mef(E), we suggest that the distinction between the two genes be maintained.  相似文献   
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