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BACKGROUND AND OBJECTIVE: Anthracyclines are highly effective and widely used cytotoxic agents, but their application is often limited by cumulative dose-dependent cardiotoxicity. Dexrazoxane has been shown in several clinical trials to prevent the development of this serious toxicity. The aim of our study was to analyze the incidence of cardiac dysfunction over a 10-year period in patients with breast cancer who were treated with anthracycline-based regimens with addition of dexrazoxane, mainly in an adjuvant setting. METHODS: We conducted a retrospective analysis on a population of women with breast cancer treated at our institution between January 1993 and October 2003. We reviewed patients' medical records and data on patient characteristics, treatment history, and adverse events that were collected, starting from the time of first visit before starting therapy, with the use of software created and designed for clinical records management in our institution (1999 OK-DHtrade mark). Patients underwent an ECG assessment prior to starting chemotherapy, and were clinically monitored for cardiac failure. Those who developed signs and symptoms suggestive of cardiac dysfunction underwent further ECG. If clinical findings indicated, echocardiography and further cardiologic investigations were performed. The main outcome measure was the development of signs and symptoms indicative of congestive heart failure (CHF). RESULTS: A total of 318 female patients were treated with an anthracycline (doxorubicin or epirubicin)-based combination chemotherapy regimen during this time, in most cases in the adjuvant setting (n = 285). Most patients (n = 302) had early-stage disease and only 16 women presented with metastatic disease with good life expectancy (at least 1 year). All patients received dexrazoxane 1000 mg/m(2) intravenously prior to anthracycline administration during each chemotherapy cycle. The median follow-up duration was 35 months. During this time, five patients (1.57%) developed signs and symptoms of CHF. No patient at our institution died of heart failure during the period analyzed. Dexrazoxane was well tolerated, with no reports of adverse events associated with this drug. CONCLUSIONS: The reported incidence of cardiotoxicity in this study represents a marked reduction compared with historical data for patients receiving anthracycline-based chemotherapy without dexrazoxane. Dexrazoxane appears to have a cardioprotective effect in women with early-stage or advanced breast cancer treated with anthracycline-based combination chemotherapy, mainly as an adjuvant treatment. Prospective, randomized, controlled clinical trials in adjuvant setting should be performed to confirm these results.  相似文献   
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In the literature, several malformations of cortical development have been described as additional lesions in tuberous sclerosis complex. Among these lesions, a very large focal cortical dysplasia has peculiar magnetic resonance imaging features: a signal abnormality that extends radially inward toward the lateral ventricle from the pachygyric cortical surface plus a homogeneous clinical picture. Affected patients have early-onset drug-resistant epilepsy and severe developmental delay. We describe the clinical, genetic, neurophysiologic, and neuroradiologic characteristics of four patients affected by tuberous sclerosis and this type of cortical dysplasia these patients are of special interest because they have been operated on for their dysplastic lesions. Total control of seizures has been achieved in the three children who underwent a complete lesionectomy. This result cannot be permanent, however, because of the presence of other cortical tubers which could become epileptogenic. All things considered, our choice was to give these children at least temporary relief from severe epilepsy and possibly support for developmental progression.  相似文献   
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AIMS AND BACKGROUND: In patients with breast cancer the presence of internal mammary chain (IMC) metastases changes tumor staging, and the occurrence of IMC drainage is quite common in breast cancer. Nevertheless, IMC dissection is not a routine procedure in modern surgical approaches towards breast cancer. We therefore need minimally invasive techniques for accurate assessment of the IMC nodal basin. The aim of this study was to investigate whether sentinel node biopsy (SLNB) could offer a solution. METHODS AND STUDY DESIGN: From November 1997 to June 2001 143 female patients who were eligible for breast cancer surgery were included in the study. All patients had T1 breast cancer and clinically negative axillae. Patients were submitted to preoperative lymphoscintigraphy with subsequent SLNB. We used a 99m-technitium nanocolloid tracer (Nanocoll) that was injected peritumorally so as to have about 10 MBq of radioactivity at the time of surgery. Scintigraphy was performed about 17 hours after tracer administration. During surgery, lymphoscintigraphic imaging and a gamma ray detection probe were used to locate the sentinel node. Histological examination after embedding in paraffin was usually requested and multilevel sectioning of the sentinel node (SLN) was performed, with hematoxylin and eosin staining and immunohistochemistry. RESULTS: Preoperative lymphoscintigraphy localized SLNs in the IMC basin in 27 of 143 patients (18.9%). Harvesting of IMC-SLNs based on lymphoscintigraphy results was successful in 20 of 27 patients (74.1%). Histological examination revealed micrometastases in four of the 20 harvested nodes. One of these patients showed no axillary drainage and no axillary lymph node dissection was therefore performed. In the remaining three patients also axillary SLNs were harvested, which turned out to be free from metastatic involvement. CONCLUSIONS: In our experience lymphoscintigraphy with SLNB was an accurate method to detect IMC metastases in patients with breast cancer. We recommend peritumoral tracer injection and a reasonable interval between injection and scintigraphy. IMC-SLN biopsy did not result in any serious additional complications or morbidity. In our study this approach led to improved cancer staging: four of 20 harvested IMC-SLNs proved to be micrometastatic. None of these four patients had metastatic axillary SLNs. Exclusive drainage to the IMC is present in only a small number of breast cancer patients, and our results suggest that it is possible to avoid unnecessary axillary node dissection in such cases.  相似文献   
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OBJECTIVE--Insulin-receptor function in humans is usually studied in vitro on readily available cells, e.g., erythrocytes and fibroblasts. Although these cells are not metabolically important targets for insulin action, information derived from them are often taken as representative of other tissues. The aim of this study was to investigate insulin receptors in vitro on erythrocytes and in vivo on one of the main insulin-target organs, the liver. RESEARCH DESIGN AND METHODS--A 16-yr-old girl affected by severe insulin resistance was identified. Insulin receptor binding was measured on the erythrocytes of the patient and of 6 nondiabetic volunteers. The biodistribution of 123I-labeled insulin was studied in vivo by scintigraphic scanning in the insulin-resistant patient and in 10 nondiabetic volunteers. RESULTS--Erythrocytes of this patient displayed a markedly reduced [125I]insulin binding. In vivo 123I-insulin biodistribution was characterized by lack of hormone uptake by the liver (4 vs. 21% of the injected dose in control subjects) contrasting with intense accumulation of radioactivity in the kidneys. CONCLUSIONS--Our studies show that defects of insulin binding can be directly demonstrated in vivo on liver receptors with a noninvasive technique with low radiotoxicity.  相似文献   
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From October 1976 to December 1990 181 pancreatic transplants were performed in our centre on 171 Type 1 (insulin-dependent) diabetic patients. Oral glucose tolerance test evaluated 1 year after surgery in 31 subjects showed an impaired glucose tolerance at 120 min (blood glucose 9.5±0.6 mmol/l). Similar results were obtained in seven patients 3 years after transplantation (blood glucose at 120 min 8.3±1.08 mmol/l). 24h metabolic profiles performed at the same intervals showed near normal blood glucose levels and good insulin release. Preliminary data concerning a randomized, comparative study between whole pancreas with bladder diversion and segmental pancreas transplantation, showed better metabolic control in the patients who received the whole pancreas, probably due to the greater islet mass grafted.  相似文献   
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The epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein whose expression is important in the regulation of breast cancer cell growth. The relationship between EGFR status (determined by an immunocytochemical assay) and various prognostic factors was investigated in 164 primary breast cancers. Overall 56% of tumours were EGFR-positive and the expression of EGFR was unrelated to axillary node status, tumour size and histological grade; and it was poorly associated with the tumour proliferative activity measured by Ki-67 immuno-cytochemistry. The relapse-free survival (RFS) probability at 3-years was significantly worse for patients with EGFR positive tumours (P = 0.003) and for those whose Ki-67 score was > 7.5% (P = 0.0027), as well as in patients with axillary node involvement (P = 0.01) and with poorly differentiated tumours (P = 0.04). Immunocytochemical determination of EGFR and cell kinetics gave superimposable prognostic information for predicting RFS with odds ratios of 3.51, when evaluated singly. In our series of patients EGFR, Ki-67 and node status retain their prognostic value concerning RFS in multivariate analysis. The 3-year probability of overall survival (OS) was significantly better in node-negative patients (P = 0.04) and was similar in EGFR-positive and negative patients. In conclusion, EGFR status appears to be a significant and independent indicator of recurrence in human breast cancer and the concomitant measurement of the tumour proliferative activity seems to improve the selection of patients with different risks of recurrence.  相似文献   
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