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Renal cell carcinoma extends into the lumen of the inferior vena cava in approximately 4% of patients at the time of diagnosis. Surgical removal of the intracaval tumor thrombus with radical nephrectomy is the preferred treatment for this malignancy. From January 1977 to June 1990, 31 such patients were examined for combined problems of renal carcinoma and intracaval tumor extension. Twenty-six of these patients underwent radical nephrectomy and vena caval thrombectomy. Ten patients had tumor thrombus confined to the infrahepatic vena cava, 11 had retrohepatic caval involvement, and 5 had extension to the level of the diaphragm or into the right atrium. Surgical approach was dictated by the level of caval involvement. Control of the suprahepatic vena cava plus temporary occlusion of hepatic arterial and portal venous inflow were necessary in some cases; cardiopulmonary bypass was required for transatrial removal of more extensive tumors. Five of the 26 patients had evidence before operation of distant metastatic disease; none of these survived beyond 12 months. The 5-year actuarial survival rate of the 21 patients without known preoperative metastatic disease was 57%. Complete surgical excision of all gross tumor appears to be critical for long-term survival in these patients.  相似文献   
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Background

Assessment of patient performance status is often subjective. Sarcopenia—measurement of muscle wasting—may be a more objective means to assess performance status and therefore mortality risk following intra-arterial therapy (IAT).

Methods

Total psoas area (TPA) was measured on cross-sectional imaging in 216 patients undergoing IAT of hepatic malignancies between 2002 and 2012. Sarcopenia was defined as TPA in the lowest sex-specific quartile. Impact of sarcopenia was assessed relative to other clinicopathological factors.

Results

Indications for IAT included hepatocellular carcinoma (51 %), intrahepatic cholangiocarcinoma (13 %), colorectal liver metastasis (7 %), or other metastatic disease (30 %). Median TPA among men (568 mm2/m2) was greater than women (413 mm2/m2). IAT involved conventional chemoembolization (54 %), drug-eluting beads (40 %), or yttrium-90 (6 %). Median tumor size was 5.8 cm; most patients had multiple lesions (74 %). Ninety-day mortality was 9.3 %; 3-year survival was 39 %. Factors associated with risk of death were tumor size (HR?=?1.84) and Child's score (HR?=?2.15) (all P?<?0.05). On multivariate analysis, sarcopenia remained independently associated with increased risk of death (lowest vs. highest TPA quartile, HR?=?1.84; P?=?0.04). Sarcopenic patients had a 3-year survival of 28 vs. 44 % for non-sarcopenic patients.

Conclusions

Sarcopenia was an independent predictor of mortality following IAT with sarcopenic patients having a twofold increased risk of death. Sarcopenia is an objective measure of frailty that can help clinical decision-making regarding IAT for hepatic malignancies.  相似文献   
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Cell and tissue engineering are now being translated into clinical organ replacement, offering alternatives to fight morbidity, organ shortages and ethico-social problems associated with allotransplantation. Central to the recent first successful use of stem cells to create an organ replacement in man was our development of a bioreactor environment. Critical design features were the abilities to drive the growth of two different cell types, to support 3D maturation, to maintain biomechanical and biological properties and to provide appropriate hydrodynamic stimuli and adequate mass transport. An analytical model was developed and applied to predict oxygen profiles in the bioreactor-cultured organ construct and in the culture media, comparing representative culture configurations and operating conditions. Autologous respiratory epithelial cells and mesenchymal stem cells (BMSCs, then differentiated into chondrocytes) were isolated, characterized and expanded. Both cell types were seeded and cultured onto a decellularized human donor tracheal matrix within the bioreactor. One year post-operatively, graft and patient are healthy, and biopsies confirm angiogenesis, viable epithelial cells and chondrocytes. Our rotating double-chamber bioreactor permits the efficient repopulation of a decellularized human matrix, a concept that can be applied clinically, as demonstrated by the successful tracheal transplantation.  相似文献   
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Patients who undergo Epstein–Barr virus (EBV) seromismatch (D+/R − ) transplants have a higher risk for the development of post‐transplant lymphoproliferative disorder (PTLD). Adult renal transplant recipients at a single institution were prospectively monitored for EBV during the first year post‐transplant. Over a 2‐year period, 34 patients (7.78%) were identified as being EBV D+/R − recipients. Patients who developed symptoms or had persistent viremia were pre‐emptively administered rituximab. Six recipients were discharged without monitoring on the protocol. Of those six, three (50%) developed PTLD and all three lost their grafts. Twenty (60.6%) of the 34 recipients developed viremia during the first year post‐transplant. Of the recipients who became viremic, six (30%) received rituximab. None of the six who received rituximab‐developed PTLD. We found that recipients who were not monitored on the protocol were more likely to have PTLD and graft loss compared to those who were (p = 0.008). Post‐transplant monitoring of adults who undergo EBV D+/R − kidney transplants for viremia and symptoms associated with EBV infection may prompt intervention which reduces the incidence of PTLD within the first year. Use of rituximab in preventing PTLD among patients with primary EBV infection requires further prospective study to determine its overall safety and efficacy.  相似文献   
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Empirical therapy for subfertility using assisted reproductive technologies recently has gained popularity; however, the cost-effectiveness of these therapies, compared with an untreated control group, has not been established. Similarly, there has been no comparative cost analysis of the utility of controlled ovarian hyperstimulation and IUI in the management of the same condition. Significant PRs in untreated couples with subfertility mandate the design and execution of controlled trials to ascertain the role of controlled ovarian hyperstimulation and IUI in infertility therapy. Various disorders of subfertility have been treated with controlled ovarian hyperstimulation and IUI. The rationale for this therapy is the increase in gamete density at the site of fertilization, as with GIFT and IVF when used for management of the same problems. The live birth rate per initiated cycle and risk of complications are similar to results recently reported for GIFT and IVF. The utility of controlled ovarian hyperstimulation and IUI still remains controversial. When the relatively low direct and indirect costs of controlled ovarian hyperstimulation and IUI are considered, acknowledging the lack of prospective, controlled studies, this procedure appears to be at least as cost-effective as GIFT and IVF.  相似文献   
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