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BACKGROUND: Acute rejection commonly occurs within the first year after heart transplantation, and then decreases in frequency with time. Recently, the long-term utility of endomyocardial biopsy during routine annual catheterization has been questioned. The purpose of this study was to retrospectively review the prevalence of biopsy-proven rejection during routine annual catheterization in our patient population, determine whether biopsies late after transplant are useful, and identify factors that correlate with late unsuspected rejection. METHODS: Biopsy results from the annual catheterization were evaluated from 1986 to August 2000. The prevalence of moderate rejection was evaluated and compared with the patient's immunosuppressive regimen; the prevalence of late rejection; and how late rejection correlated with recipient age, number of first-year rejections and presence of sub-therapeutic cyclosporine. RESULTS: A total of 1108 biopsies were performed in 269 children with a mean follow-up of 5 +/- 3 years (median 5 years, range 1 to 11 years). Three-drug immunosuppressive therapy, including steroids, was used in 93 patients. There was a persistent 8% to 10% prevalence of moderate rejection at up to 10 years post-transplantation. Moderate rejection was more likely in patients: (1). on 3-drug immunosuppressive therapy; (2). with a recipient age >1 year; and (3). with a relatively lower cyclosporine level. CONCLUSIONS: These data suggest that continued surveillance of pediatric transplant patients for acute rejection is indicated for long-term follow-up.  相似文献   
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In the present study, the effect of green tea extract (GTE) on lead induced toxicity was studied in Sprague–Dawley rats. Four groups of rats were used in the study. Lead and GTE was given orally to the rats with drinking water for 8 weeks. Lead concentration in the digested tissues of liver was detected using atomic absorption spectroscopy. The activities of glutathione-S-transferase (GST) and superoxide dismutase (SOD) were used as markers to evaluate the anti oxidant status of tissues. Lead exposure was found to attenuate the antioxidant potential of liver, which was however augmented when supplemented with green tea extract. Liver enzymes ALT, AST and ALP and serum protein determinations indicated the protective effects of green tea extract. Histopathological studies of liver revealed that supplementation of green tea extract resulted in mild degeneration and congestion of the blood vessels and an enhanced regenerative capacity.  相似文献   
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Breast Cancer Research and Treatment - Breast cancer survivors are often prescribed medications for at least 5 years to reduce recurrence risk, yet some forego this treatment due to cost....  相似文献   
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Renal dopamine plays an important role in maintaining sodium homeostasis and blood pressure (BP) during increased sodium intake. The present study was carried out to determine whether renal dopamine D1 receptor (D1R) dysfunction contributes to increase in salt sensitivity during oxidative stress. Male Sprague-Dawley rats, divided into various groups, received tap water (vehicle); 1% NaCl (high salt [HS]); L-buthionine sulfoximine (BSO), an oxidant; and HS plus BSO with or without Tempol, an antioxidant, for 12 days. Compared with vehicle, HS intake increased urinary dopamine production and decreased basal renal Na/K-ATPase activity but did not affect BP. BSO-treated rats exhibited oxidative stress and a mild increase in BP. In these rats, D1R expression and G protein coupling were reduced, and SKF38393, a D1R agonist, failed to inhibit Na/K-ATPase activity and promote sodium excretion. Concomitant administration of BSO and HS caused oxidative stress, D1R dysfunction, and a marked increase in BP. Although renal dopamine production was increased, it failed to reduce the basal Na/K-ATPase activity in these animals. Treatment of BSO plus HS rats with Tempol decreased oxidative stress and restored endogenous, as well as exogenous, D1R agonist-mediated Na/K-ATPase inhibition and normalized BP. In conclusion, during HS intake, the increased dopamine production via Na/K-ATPase inhibition prevents an increase in BP. During oxidative stress, D1R function is defective, and there is mild hypertension. However, in the presence of oxidative stress, HS intake causes marked elevation in BP, which results from a defective renal D1R function leading to the failure of dopamine to inhibit Na/K-ATPase and promote sodium excretion.  相似文献   
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Yield of dual endoscopy for positive fecal occult blood test   总被引:4,自引:0,他引:4  
OBJECTIVES: Dual endoscopy is frequently performed on the same day in patients whose stools are found to be positive on fecal occult blood testing (FOBT). This is often done to localize the potential sources of GI bleed. The diagnostic yield of same day dual upper endoscopy (EGD) and lower endoscopy (colonoscopy) for the detection of positive FOBT is uncertain. In the era of cost-efficient medical practice, we investigated whether a more evidence-based and structured approach could be used to guide physicians to the workup of patients who present with positive FOBT. METHODS: We performed a retrospective analysis of 309 patients, and 260 patients from this population met our inclusion criteria. Inclusion criteria included FOBT without acute GI hemorrhage, hematochezia, or melena. Patients were required to have had EGD and colonoscopy within the same day (<24 h). RESULTS: Of 260 patients, a total of 135 (52%) patients had positive findings on colonoscopy and a total of 42 (16.1%) patients had positive findings on EGD. Sixteen (6.1%) had positive EGD and negative colonoscopy; 109 (42%) had positive colonoscopy and negative EGD; and 26 (10%) had positive findings on both EGD and colonoscopy. CONCLUSIONS: Colonoscopy should be chosen as the initial procedure of choice in the evaluation of patients who present with positive FOBT. Same day dual endoscopy does not seem to be cost-effective.  相似文献   
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Annals of Surgical Oncology - Multifocality and multicentricity are increasingly recognized in breast cancer. However, little is known about the characteristics and biology of these cancers and the...  相似文献   
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