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61.
BACKGROUND: The current study sought to delineate prospectively the rates and clinical course of emotional distress, cognitive impairment, and quality of life (QOL) in chemotherapy-naive patients with cancer and to consider the determinants of global QOL. METHODS: Patients who consented to participate were administered the European Organization for Research and Treatment of Cancer QLQ-C30 questionnaire, the Mini-Mental State Examination (MMSE), and the Hospital Anxiety and Depression Scale before and at the end of treatment (EOT). RESULTS: Of the 102 patients initially assessed, 80 (78.4%) completed the study. Most aspects of QOL did not change considerably over time. At EOT, patients reported only significant increases in fatigue and significant decreases in sleep disturbance. Although no significant changes emerged in the rates of anxiety or depression throughout chemotherapy, nearly one-third of the patients experienced severe emotional distress at both points in time. In addition, the authors observed neither significant alteration in the cognitive performance over time nor reliable associations between scores on the MMSE and subjective cognitive function, emotional distress, or QOL. Finally, depression proved to be the leading predictor of global QOL at baseline and at EOT. CONCLUSIONS: The results indicated that a significant proportion of Greek patients with cancer experienced intense anxiety and depression throughout chemotherapy and confirmed the importance of depression as a strong predictor of global QOL. Routine screening of emotional distress across all phases of cancer is mandatory because it will contribute to the identification of patients who are in need of pharmaceutical and/or psychologic intervention.  相似文献   
62.
PURPOSE: In view of the need for dose-validation procedures on each individual intensity-modulated radiation therapy (IMRT) plan, dose-verification measurements by film, by ionization chamber, and by polymer gel-MRI dosimetry were performed for a prostate-treatment plan configuration. Treatment planning system (TPS) calculations were evaluated against dose measurements. METHODS AND MATERIALS: Intensity-modulated radiation therapy (IMRT) treatments were planned on a commercial TPS. Kodak EDR-2 films were used for the verification of two-dimensional (2D) dose distributions at 1 coronal and 5 axial planes in a water-equivalent phantom. Full three-dimensional (3D) dose distributions were measured by use of a novel polymer gel formulation and a 3D magnetic resonance imaging (MRI) readout technique. Calculations were compared against measurements by means of isocontour maps, gamma-index maps (3% dose difference, 3-mm distance to agreement) and dose-volume histograms. RESULTS: A good agreement was found between film measurements and TPS predictions for points within the 60% isocontour, for all the examined plans (gamma-index <1 for 96% of pixels). Three-dimensional dose distributions obtained with the polymer gel-MRI method were adequately matched with corresponding TPS calculations, for measurements in a gel phantom covering the planning-target volume (PTV). CONCLUSIONS: Measured 2D and 3D dose distributions suggest that, for the investigated prostate IMRT plan configuration, TPS calculations provide clinically acceptable accuracy.  相似文献   
63.
OBJECTIVE: To assess the bioequivalence of 2 oral cefuroxime axetil (250 mg) tablets formulation. The reference preparation was Zinadol/Glaxo Wellcome, England, while the test preparation was cefuroxime axetil/Pharmathen, Athens, Greece. SUBJECTS, MATERIAL AND METHODS: The study was an open, randomized, 2-period, 2-sequence, 2-treatment crossover, involving 24 healthy male and female volunteers. All volunteers completed the study. Cefuroxime axetil plasma concentrations were measured utilizing a sensitive, reproducible and accurate HPLC method. Care was taken through the collection and analysis of the samples due to instability of cefuroxime axetil in light. Pharmacokinetic parameters used to assess bioequivalence were AUC(0-last), AUC(0-inf) for the extent of absorption and Cmax and tmax for the rate of absorption. Statistical evaluation of Cmax, AUC(0-last), and AUC(0-inf) was done using 2-way analysis of variance (ANOVA) after semilogarithmic transformation. Tmax values were tested using the distribution-free Hodges-Lehman interval. RESULTS: The parametric 90% confidence intervals for ratio T/R ranged from 98.91-111.65% (point estimate 105.09%) for AUC(0-last), 99.41-111.78% (point estimate 105.41%) for AUC(0-inf) and 87.61-102.89% (point estimate 94.95%) for Cmax, respectively. Based on the results of tmax, K(el) and t(1/2) there were no statistically significant differences. CONCLUSION: The 2 cefuroxime axetil preparations, examined in accordance with the European Union bioequivalence requirements, are equivalent with respect to rate and extent of absorption.  相似文献   
64.
The deleted in colorectal cancer (DCC) gene is a candidate tumor suppressor gene that may be associated with differentiation and proliferation of normal cells. Loss of heterozygosity (LOH) of 18q, where the gene is located, and absence of DCC protein expression have been associated with worse prognosis in certain subgroups of patients with colorectal adenocarcinoma. We studied the prognostic significance of loss-of-protein expression in 66 patients with resected gastric cancer with a high probability of relapse (T3, T4, N+). The DCC protein was detected with immunohistochemistry using an anti-DCC monoclonal antibody on paraffin-embedded sections. The DCC protein expression was present in 51 cases (77.3%) and absent in 15 cases (22.7%). Poorly differentiated and signet ring carcinomas had significantly lower expression than more differentiated tumors (p < 0.05) as did diffuse-type tumors compared to intestinal and mixed (p < 0.01). There was no correlation with proliferation rate, estimated immunohistochemically using an anti-proliferating cell nuclear antigen (PCNA) monoclonal antibody. Absence of DCC protein was an independent favorable prognostic factor (median survival 57 months vs. 18 months, p = 0.0176). The DCC protein expression was correlated with relapse site: all patients with distant metastases were positive for DCC staining, while one-third of patients with local/peritoneal relapse were negative (p < 0.01). In conclusion, DCC protein expression seems to be a significant prognostic factor in high-risk resected gastric cancer. Our results support previous data associating the DCC gene with differentiation and indicate that this gene may play a role in the metastatic potential of these tumors. These findings need to be confirmed by future larger studies.  相似文献   
65.
66.
Yao KA  Talamonti MS  Nemcek A  Angelos P  Chrisman H  Skarda J  Benson AB  Rao S  Joehl RJ 《Surgery》2001,130(4):677-82; discussion 682-5
BACKGROUND: We reviewed 36 patients with liver metastases from islet cell tumors of the pancreas (n = 18) and carcinoid tumors (n = 18) who were treated with surgical resection (n = 16) or hepatic chemoembolization (n = 20). METHODS: All resections were complete and included 4 lobectomies, 6 segmental resections, and 6 wedge resections. There were no operative deaths. RESULTS: Median survival has not yet been reached, and the actuarial 5-year survival rate is 70%. Prognostic variables associated with improved disease-free survival included prior resection of the primary tumor and 4 or fewer metastases resected (P <.05). With an average of 3 chemoembolization procedures per patient, 17 of 20 patients (90%) demonstrated either a significant radiographic response (n = 5), stabilization of tumor mass (n = 2), or improvement of clinical symptoms (n = 10). Factors related to a sustained response (more then 1 year) included surgical resection of the primary tumor, 4 or more chemoembolization procedures, and liver metastases of 5 cm or smaller. Median survival after treatment was 32 months (range, 7-63 months), and the actuarial 5-year survival rate was 40%. CONCLUSIONS: Surgical resection of metastatic neuroendocrine tumors provides the best chance for extended survival. Chemoembolization effectively improves clinical symptoms and, in selected patients, may provide sustained tumor control.  相似文献   
67.
OBJECTIVE: To determine whether epinephrine in combination with high flow worsens left ventricular (LV) myocardial high-energy phosphate stores during reperfusion of ischemic ventricular fibrillation (VF). DESIGN: Blinded, prospective block randomized, placebo controlled study. SETTING: University medical center research laboratory. SUBJECTS: A total of 22 mixed breed swine weighing 22.0+/-3.3 kg (SD). INTERVENTIONS: Open-chest swine, anesthetized with alpha-chloralose, underwent 10 mins of nonperfused VF followed by reperfusion with cardiopulmonary bypass for 90 mins and then defibrillation. Animals were block randomized to four groups for reperfusion: Group 1 (n = 5), high flow (100 mL/kg/min) and epinephrine (2.5 microg/kg/min); Group 2 (n = 5), high flow and placebo; Group 3 (n = 6), low flow (30 mL/kg/min) and epinephrine; and Group 4 (n = 6), low flow and placebo. MEASUREMENTS AND MAIN RESULTS: In vivo LV creatine phosphate (CP) and adenosine triphosphate (ATP) were determined using whole wall and spatially localized 31P NMR spectroscopy at 4.7 Tesla. During perfusion of the fibrillating myocardium, epinephrine significantly increased aortic pressure (p < .05) and improved defibrillation rates (p < .01). ATP levels during reperfusion were significantly decreased within all groups compared with baseline. There were no differences in ATP levels between groups. High flow, independent of epinephrine, was associated with increased preservation of ATP (p < .05), increased CP/ATP ratios (p < .02) in all layers of the LV wall, and decreased aortic and cardiac vein lactates (p < .001). CONCLUSIONS: Epinephrine, in combination with flow higher than standard cardiopulmonary resuscitation flows, increased perfusion pressure and defibrillation rates, but did not significantly alter myocardial ATP during VF reperfusion in the in vivo heart Reperfusion flow, independent of epinephrine, is a critical determinant of myocardial ATP preservation.  相似文献   
68.
69.
BACKGROUND AND PURPOSE: Nasopharyngeal carcinoma (NPC) represents a seldom malignancy in most developed countries. Nevertheless, NPC receives an endemic form in concrete racial entities. The aims of this study were to detect the presence of Epstein-Barr virus DNA (EBV-DNA) in peripheral blood of NPC patients, to molecularly define human leukocyte antigens (HLA) DRB1*, DQA1* and DQB1* allele frequencies, and, finally, to determine whether the genetic predisposition of an individual to NPC depends on the liability to EBV infection. PATIENTS AND METHODS: A total of 101 patients of Hellenic origin and nationality, with histologically proven NPC, participated in this study. EBV-DNA detection was also applied in 66 patients with EBV-related malignancies (Hodgkin's [HL] and non-Hodgkin's lymphoma [NHL]) and infectious mononucleosis (IM), as well as in 80 healthy EBV-seropositive controls. RESULTS: 81% of the NPC patients, 77.8% with HL, 72.2% with NHL, and 66.7% with IM were EBV-DNA positive, whereas the EBV genome was detected only in 15% of the healthy controls. These differences were statistically significant in all cases. Analysis of HLA class II antigens showed decreased frequency of the DRB1*07 (p = 0.003), DQA1*0103 (p = 0.002), and DQA1*0201 (p = 0.003) alleles among NPC patients. A significant association between the HLA-DR/DQ alleles and the presence of EBV-DNA in peripheral whole blood was not established. CONCLUSION: Circulating EBV-DNA and specific HLA class II alleles may predispose to or protect from NPC. However, the results of this study suggest that the genetic predisposition of an individual to NPC is independent of the liability to EBV infection.  相似文献   
70.
Ventricular fibrillation (VF) remains the most common cardiac arrest heart rhythm. Defibrillation is the primary treatment and is very effective if delivered early within a few minutes of onset of VF. However, successful treatment of VF becomes increasingly more difficult when the duration of VF exceeds 4 minutes. Classically, successful cardiac arrest resuscitation has been thought of as simply achieving restoration of spontaneous circulation (ROSC). However, this traditional approach fails to consider the high early post-cardiac arrest mortality and morbidity and ignores the reperfusion injuries, which are manifest in the heart and brain. More recently, resuscitation from cardiac arrest has been divided into two phases; phase I, achieving ROSC, and phase II, treatment of reperfusion injury. The focus in both phases of resuscitation remains the heart and brain, as prolonged VF remains primarily a two-organ disease. These two organs are most sensitive to oxygen and substrate deprivation and account for the vast majority of early post-resuscitation mortality and morbidity. This review focuses first on the initial resuscitation (achieving ROSC) and then on the reperfusion issues affecting the heart and brain.  相似文献   
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