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The clinicopathologic features of osteosarcoma in 12 children younger than 16 years of age treated at The Children's Hospital and Dana-Farber Cancer Institute, Boston, during a 70-year time period are presented. Only one of six children treated before 1972 is a long-term survivor. Four of six children (67%) treated after 1972 are disease-free with an average follow-up of 8.8 years. The year 1972 marked the onset of use of effective chemotherapy in osteosarcoma, namely, high-dose methotrexate and leucovorin rescue. It would appear that the pathologic features and behavior of osteosarcoma in young children is similar to that of osteosarcoma in older children and adolescents. A combination of complete (wide) surgical resection or amputation and aggressive chemotherapy offers the best chance of long-term survival.  相似文献   
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Experimental studies demonstrated a severe cardiac load of the CO2 pneumoperitoneum caused by an accelerated after- and a decreased preload. Patients displaying cardiovascular risks are therefore often rejected from laparoscopic surgery. Hence, the pathophysiological changes and the intraoperative risk of the CO2 pneumoperitoneum in high-risk cardiopulmonary patients (NYHA II–III, n= 15) undergoing laparoscopic cholecystectomy are described. The changes in cardiac after- and preload seem to be due to the elevated intraabdominal pressure rather than transperitoneally resorbed CO2 and are reversible by desufflation. In one patient conversion to open operation had to be performed because of a severe drop in cardiac output and right ventricle ejection fraction. Mixed oxygen saturation was predicting intraoperative worsening in this case. The described pathophysiological changes may seem to be well tolerated even in high-risk cardiac patients. Monitoring of hemodynamics should include an arterial catheter line and blood gas analyses. Pharmacologic interventions or pressureless laparoscopic procedures might not be necessary as long as laparoscopic cholecystectomy is performed. Received: 13 December 1996/Accepted: 8 January 1997  相似文献   
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In contrast to conventional film angiography, the perfusion pattern of hepatic arterial chemotherapy was consistently visualized by DSA in 40 patients with implanted Infusaid pump or Port-A devices. Incomplete perfusion of a liver region by the cytotoxic agent was recognized by DSA as accurately as by nuclide scintigraphy. Furthermore, DSA appeared to be more sensitive in determining aberrantly perfused extrahepatic regions; this was especially true when there was a nonligated right hepatic artery. Specific details of vascular lesions and associated complicating events also could be satisfactorily analyzed by DSA only.  相似文献   
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We present a new concept after Schultheis which is based on the results of experimental studies on cell cultures. Local chemoembolization in liver tumours including liver metastases is usually performed via the angiographic route. Embolisation of the most peripheral branches of the hepatic artery prevents early formation of collateral vessels. The method also comprises the additional infusion of cytostatic agents via the portal vein. The procedure is usually repeated after an interval of about four weeks. In this paper we will describe our method in liver metastases and present the preliminary results obtained from 19 patients treated to date.  相似文献   
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With regard to disturbances of the iron metabolism, porphyria cutanea tarda (PCT) is most frequently accompanied by liver siderosis. In 74 out of 88 patients suffering from PCT (84%), we found histochemical evidence of liver siderosis. These patients showed a significantly higher incidence of HLA A3--which has been proved to be associated with hemochromatosis--than those without liver siderosis (39.2% vs. 7.1%). With part of the PCT patients, disorders of the iron metabolism related to the HLA system (A3) might contribute to the manifestation of the disease. We discuss PCT as the result of the combined action of several predisposing genetic markers and exogenic factors.  相似文献   
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In a prospectively randomized study we used two different ways of drainage of the sacral space after an abdomino-perineal-resection of the rectum. One group with 25 patients had a drainage anteriorly through the abdominal wall, the other 25 patients got a drainage posteriorly through the buttocks. In each case we used two closed silicone-drainage-systems without active suction. In 60% of the anterior and in 50% of the posterior drained cases we saw an unaffected primary healing of the sacral wound. There was no significant difference. The patients felt the anterior way of drainage to be more convenient. Contamination of the sacral space by disrupture of the rectum during the operation was followed by a sacral abscess in 50%.  相似文献   
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A 19-year-old woman presented with a large mediastinal mass, histologically shown to be malignant lymphoma of lymphoblastic type (LBL). Immunophenotypic and gene rearrangement analysis unequivocally demonstrated that the neoplasm was of B-cell lineage. The neoplastic cells expressed terminal deoxynucleotidyl transferase, the pan-B cell antigens CD19, CD20, and CD22, and were negative for immunoglobulins and numerous T-cell antigens tested. Southern blot analysis showed rearrangement of one allele of the immunoglobulin heavy chain gene while the immunoglobulin kappa and T-cell receptor beta chain genes were in the germline configuration. Thus, the immunophenotypic and molecular findings in this case correspond to an early stage of B-cell differentiation, the pre-pre B-cell stage as has been named by others. In contrast with LBL of immature T-cell lineage, precursor B-cell LBLs involving the mediastinum are truly rare. Occasional cases have been reported that have arisen elsewhere and subsequently involved the mediastinum at time of relapse or tumor progression. Well-documented examples of immature B-cell LBL arising in the mediastinum are virtually unreported. The site and cell population giving rise to this neoplasm is unknown. However, origin from precursors of normal thymic medullary B cells is proposed as one possibility.  相似文献   
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