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81.
BACKGROUND: When used in conjunction with steroids and cyclosporin, mycophenolate mofetil (MMF) has been shown to significantly reduce mortality and incidence of rejection in the first year after heart transplantation. It also appears that in this early post-transplantation period, the monitoring of immunosuppressive therapies may be warranted. The current study was undertaken to determine if such monitoring is still useful more than 1 yr after heart transplantation. METHODS: Twenty-six patients who had survived the first year after orthotopic heart transplantation and had been on MMF therapy for more than 3 months were prospectively followed. At the time of their routine endomyocardial biopsy blood samples were taken to monitor immunosuppressive therapy. Most patients had two samples taken, on average 109 d apart. RESULTS: There were 22 episodes of asymptomatic rejection documented on a total of 48 biopsies. Of these, only two were of ISHLT (International Society for Heart and Lung Transplantation) grade 3A the remainder being of ISHLT grades 1 or 2. There was no relation between immunosuppressive regimen (tacrolimus and MMF or cyclosporin and MMF) and rejection. There was no relation between monitored immunosuppressive levels and rejection. Patients with the combination of MMF and tacrolimus had significantly higher plasma mycophenolic acid levels despite significantly lower daily MMF dose. CONCLUSION: There does not appear to be a benefit in continued monitoring of plasma mycophenolic acid levels beyond the first year of heart transplantation. There were significant differences in plasma mycophenolic acid levels depending on the type of calcineurin inhibitor concomitantly used.  相似文献   
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Outcome of sibling vesicoureteral reflux.   总被引:3,自引:0,他引:3  
PURPOSE: We determine the efficacy of a prospective screening analysis of an asymptomatic sibling of patients with reflux. MATERIALS AND METHODS: A total of 78 siblings of patients with reflux were evaluated and 40 (51%) had reflux. The resolution rate and necessity for surgical intervention were evaluated. RESULTS: A total of 40 patients had vesicoureteral reflux, including grade I in 12, II in 33, III in 19 and IV in 1. No patient had gross renal scar on ultrasound or renal pelvis dysmorphism on voiding cystourethrogram. Treatment consisted of prophylactic antibiotics in all. One patient required surgical correction for breakthrough urinary tract infection. Followup was available in 31 patients, of whom reflux resolved completely with medical management in 26. Reflux was downgraded in 4 patients. Of the patients in whom reflux resolved completely grades I to II vesicoureteral reflux were in 18, and II to IV in 8. Mean time to resolution was 15.6 months. CONCLUSIONS: The incidence of sibling reflux is significant. However, grade specific time to resolution appears to be decreased compared to primary reflux diagnosed after urinary tract infection. Furthermore, the incidence of renal damage appears to be decreased compared to "traditional" reflux. Although it is reasonable to recommend screening, we suggest that sibling reflux may follow a more benign course.  相似文献   
84.
BACKGROUND: Telomere shortening at every replication cycle is postulated to limit the life span of human somatic cells. In contrast, activation of telomerase is proposed to be an essential step for cancer cell immortalization. Head and neck cancer is the most common malignancy in the Indian population compared with Western countries. However, there are very few reports on telomerase activity and telomere length in head and neck cancer. METHODS: Telomerase activation and telomere length alterations were studied in tumor and adjacent normal tissues in 110 patients with head and neck cancer and 40 patients with precancerous/benign conditions. Telomerase activity and telomere lengths were determined by Telomeric Repeat Amplification Protocol (TRAP assay) and Southern blot analysis, respectively. RESULTS: Telomerase activation was observed in 78.2% of the malignant tissues, 85% of the precancerous tissues, and 53.1% of the adjacent normal tissues. Peak terminal restriction fragment length (TRF) was observed to be significantly lower in malignant tissues compared with the adjacent normal tissues. No significant correlation could be observed between telomerase activation and clinicopathologic characteristics of the patients. Two-year disease-free survival analysis showed that patients showing telomerase activation in the adjacent normal tissues and patients showing higher telomere length in malignant tissues had poor disease-free survival. CONCLUSIONS: Our results demonstrate the significant clinical usefulness of telomerase activation and telomere length for head and neck cancer patients. These markers may be helpful in predicting the clinical course of the disease and thus in identifying the patients in need of a close follow-up and vigorous adjuvant treatment.  相似文献   
85.
Background Urogenital melanoma is a rare neoplasm with poor prognosis. Its management in the past involved radical vulvectomy and complete bilateral inguinofemoral lymphadenectomy. Sentinel lymph node biopsy is an accurate low-morbidity procedure when used in the context of cutaneous melanoma. However, prophylactic lymphadenectomy has not been shown to improve survival of melanoma patients. We wanted to determine the feasibility of sentinel lymph node biopsy in patients with female urogenital melanoma as a staging procedure. Methods Six patients with vulvar or vaginal melanomas underwent preoperative lymphatic mapping with99mTc-labeled sulfur colloid followed by sentinel lymphadenectomy. In addition, we reviewed the literature on the application of sentinel lymph node biopsy in urogenital tract melanomas. Results One or more sentinel nodes were identified in all six patients by lymphoscintigraphy. All patients underwent sentinel lymphadenectomy, except for one patient with a deep vaginal melanoma that drained to pelvic nodes. The five successful cases had unilateral drainage patterns. None of the sentinel lymph nodes excised had tumor invasion. Combined with five other patients from the published literature, the success rate of localizing sentinel lymph nodes in the patients with urogenital melanoma approaches 100%. Conclusions This experience, plus reports of a small number of patients from three similar studies, supports the impression that sentinel lymph node biopsy is feasible for vulvar and vaginal melanoma.  相似文献   
86.
Patients with acute leukemia who undergo hematopoietic stem cell transplantation (HSCT) are susceptible to malnutrition caused by several factors including intensive cytotoxic therapy. This paper discusses the significance of malnutrition in these patients and provides an overview of nutrition therapy by the oral, enteral, and parenteral routes. The goal is to investigate whether the use of parenteral nutrition (PN) produces improved clinical outcomes in patients with acute leukemia and to identify criteria for the selection of patients most likely to benefit from this therapy. Although PN may be appropriate for patients suffering from complications such as graft-versus-host disease (GVHD) and mucositis, the data available at this time do not support PN as first-line therapy for all recipients of HSCT.  相似文献   
87.
BACKGROUND: We report on a controlled trial of a mixed amphetamine salts compound (Adderall, dextroamphetamine sulfate, dextro-, levoamphetamine sulfate, dextroamphetamine aspartate, levoamphetamine aspartate, and dextroamphetamine saccharate) in the treatment of adult attention-deficit/hyperactivity disorder (ADHD). METHODS: This was a 7-week, randomized, double-blind, placebo-controlled, crossover study of Adderall in 27 well-characterized adults satisfying full DSM-IV criteria for ADHD of childhood onset and persistent symptoms into adulthood. Medication was titrated up to 30 mg twice a day. Outcome measures included the ADHD Rating Scale and the Clinical Global Impression Score. Comorbid psychiatric disorders were assessed to test for potential effects on treatment outcome. RESULTS: Treatment with Adderall at an average oral dose of 54 mg (administered in 2 daily doses) was effective and well tolerated. Drug-specific improvement in ADHD symptoms was highly significant overall (42% decrease on the ADHD Rating Scale, P<.001), and sufficiently robust to be detectable in a parallel groups comparison restricted to the first 3 weeks of the protocol (P<.001). The percentage of subjects who improved (reduction in the ADHD rating scale of > or =30%) was significantly higher with Adderall treatment than with a placebo (70% vs 7%; P =.001). CONCLUSIONS: Adderall was effective and well tolerated in the short-term treatment of adults with ADHD. More work is needed to evaluate the long-term effects of Adderall, or other amphetamine compounds, in the treatment of adults with ADHD.  相似文献   
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Background  

Although clinical research is integral to the advancement of medical knowledge, physicians face a variety of obstacles to their participation as investigators in clinical trials. We examined factors that influence the participation of gastroenterologists and hepatologists in clinical research.  相似文献   
90.
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