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81.
The catechol-O-methyltransferase (COMT) Val158Met polymorphism modulates executive functions and working memory and recent neuroimaging studies implicate an association with emotional processing. We examined the relationship between the COMT Val158Met polymorphism and facial emotion recognition and differentiation in 100 healthy individuals. Compared to Met homozygosity, Val homozygosity was associated with better and faster recognition of negative facial expressions such as anger and sad. Our study provides evidence for a possible influence of the COMT polymorphism on emotion recognition abilities in healthy subjects. Additional research is needed to further define the neurocognitive phenotypes associated with COMT polymorphisms.  相似文献   
82.
Erythropoietic protoporphyria (EPP) is a disease of the heme metabolism due to a deficiency of ferrochelatase, leading to accumulation of protoporphyrin (PPIX) in the erythrocyte (red blood cell [RBC]). The major clinical manifestation in EPP is photosensitivity; however, in a small number of patients liver failure is a significant complication and liver transplantation is the only treatment option. Damage to both abdominal skin and organs occurs when exposed to operating light; however, this problem can be ameliorated by the use of filters that block the transmission of light with wavelength below 470 nm. A more unusual but very serious complication postoperatively is severe motor neuropathy, with few or no known acute available precautions. An effective treatment option is needed to manage EPP crises and to prevent complications after liver transplantation. We successfully treated a patient with EPP-induced liver failure with the molecular adsorbents recirculating system (MARS) and Prometheus in independent sessions. Following treatment with MARS we found a 9.1% reduction of the RBC-PPIX concentration and a 5.9% reduction after treatment with the Prometheus system. Plasmapheresis made a reduction in RBC-PPIX concentration of 0.8%. Following treatment sessions with MARS and Prometheus, the clinical condition was markedly improved and orthotopic liver transplantation was performed without further complications. In conclusion, extracorporeal therapy with MARS or Prometheus seems to be efficient in reducing RBC-PPIX concentration in comparison to plasma exchange.  相似文献   
83.
The aim of this study was to compare nonfluoroscopic electroanatomic mapping (NOGA), SPECT perfusion imaging, and PET metabolic imaging for assessment of myocardial viability. In particular, we sought to elucidate differences of electromechanical properties between the perfusion/metabolism mismatch as an indicator of a potentially reversible ischemic injury and the perfusion/metabolism match indicating irreversibly damaged myocardial tissue. METHODS: Twenty-one patients with coronary artery disease underwent NOGA mapping of endocardial unipolar voltage, cardiac 18F-FDG PET of glucose utilization, and resting 201Tl SPECT of myocardial perfusion. RESULTS: Electrical activity was 10.8 +/- 4.6 mV (mean +/- SD) in normal myocardium and was unchanged in hypoperfused segments with maintained glucose metabolism (perfusion/metabolism mismatch), 9.3 +/- 3.4 mV (P = not significant). In contrast, hypoperfused segments with a perfusion/metabolism match and nonviable segments showed significantly lower voltage (6.9 +/- 3.1 mV, P < 0.0001 and 4.1 +/- 1.1 mV, P < 0.0001 vs. normal). In hypoperfused segments, metabolic activity was more closely related to endocardial voltage than was myocardial perfusion (201Tl vs. voltage: r = 0.38, SEE = 3.2, P < 0.001; 18F-FDG PET vs. voltage: r = 0.6, SEE = 2.8, P < 0.0001). CONCLUSION: In hypoperfused myocardium, electrical activity by NOGA mapping is more closely related to PET metabolic activity than to SPECT myocardial perfusion. As NOGA mapping does not differentiate hypoperfused myocardium with enhanced glucose utilization from normal myocardium, results from NOGA mapping need to be correlated with results from perfusion imaging to identify hypoperfused, yet viable, myocardium and to stratify patients for revascularization procedures.  相似文献   
84.
85.
Aim: There is strong evidence that hepatocellular apoptosis is not only initiated by circulating blood cells which become adherent within the endotoxemic liver, but also contributes to further sustain the inflammatory cell-cell response. Methods: Because previous studies assumed the importance of the role of cellular cross-talk in mediating inflammatory liver injury, we herein examined the activation of Kupffer cells (KCs) and their spatial coincidence with intrahepatic leukocyte adherence and hepatocellular apoptosis at 6 h after intraperitoneal exposure of rats with lipopolysaccharide (10 mg/kg). Results: In vivo multifluorescence microscopy revealed liver injury including nutritive perfusion failure, tissue hypoxia, leukocyte accumulation, as well as KC activation and parenchymal apoptotic cell death. Detailed spatial analysis revealed frequent colocalization of activated KCs with apoptotic hepatocytes. Colocalization was absent in saline-treated controls.Colocalization was confirmed by histochemistry, which showed ED1-positive KCs neighboring and engulfing TUNEL-positive hepatocytes. Colocalization of KCs with leukocytes ranged between 4% and 5% and did not increase in endotoxemic animals. Taken together, the present results indicate that apoptotic cell death of hepatocytes may stimulate phagocytosis by neighboring KCs. Direct KC-leukocyte contact seems not to be mandatory for cellular communication in the process of hepatocellular apoptosis. Conclusion: With respect to the fundamental importance of cell apoptosis, improved knowledge of these cell-cell interactions might allow the development of new therapeutic strategies through the regulation of apoptotic cell death.  相似文献   
86.
We report on an unusual case of a young female patient who received an implantable LVAD after unsuccessful emergency coronary bypass surgery following acute myocardial infarction. After LVAD placement, it became evident that the patient had been pregnant. She had to undergo gynaecological surgery during mechanical support to remove the deceased fetus.  相似文献   
87.
PURPOSE, MATERIAL AND METHODS: The dose calculation accuracy of the voxel-based Monte Carlo (VMC++) electron dose module of Oncentra MasterPlan (Nucletron B.V., Veenendaal, The Netherlands) was verified by measurements in homogeneous water phantoms. RESULTS: Measured and calculated dose maxima on the central beam axis (calculations with 10,000-20,000 incident electron histories per cm(2)) agree well using standard applicator configurations as well as individually shaped inserts. Profile scans with higher electron energies (>/= 15 MeV) reveal differences up to 5% especially in the penumbra region. Depth dose curves agree best in the vicinity of maximum depths. In the buildup region energy-dependent differences up to 5% in both directions could be observed. In the decay region of depth dose curves calculated doses were up to 10% higher than measured values. CONCLUSION: Good VMC++ accuracy combined with moderate computing times of 1-15 min per beam satisfy all clinical needs. VMC++ allows, for the first time, accurate routine dose evaluations of radiation therapy with electrons. Adequate positioning of the dose reference point is essential. Even small displacements may significantly influence the calculation of monitor units.  相似文献   
88.
Introduction Failure to enter the coronary sinus (CS) with a guiding catheter and entering its tributaries remains challenging in left ventricle (LV) pacing lead implants for cardiac resynchronization therapy (CRT). A dual telescoping catheter system (8F outer/6F inner) is designed to provide the ability to adjust the catheter curve size, shape and/or reach to the patients’ anatomy avoiding the need for catheter change. Methods Five different designs for CS cannulation were randomly tested in 64 patients scheduled for CRT device implant. Results In 33 consecutive patients three adaptable telescoping guiding catheter systems were tested per patient, the adaptable catheters had higher overall cannulation success rates (68, 63 and 62%) compared to the fixed shape catheter (46%) and an greater cannulation success rate when the CS location was not known (70, 53 and 72% vs 33% for the fixed shape). In a second group of 31 CRT patients the two telescoping catheters had similar high levels of success (71–80%), with or without using the inner catheter. Conclusions The telescopic system is adaptable to a wide range of anatomical variations in patients and can result in a higher CS cannulation success rate due to its adjustability in the RA in search for the CS ostium. On top of this the inner catheter allows for sub-selecting the CS tributaries.  相似文献   
89.
BACKGROUND: A carbonated apatite cement (NORIAN SRS) was used as a bone mineral substitute for the calvaria or viscerocranium in 27 patients. It has the consistency of a paste and hardens at physiologic pH and body temperature due to dahllite crystallization, which has the stoichiometric formula Ca(8.8)(HPO(4))(0.7)(PO(4))(4.5)(CO(3))(0.7)(OH)(1.3). MATERIAL AND METHODS: The cement was used for posttraumatic bone defects in the orbital, periorbital or malar regions (nine patients), posttraumatic deformities of the frontal bone (six patients), tumour-dependent bony defects of the calvaria (two patients) and posttraumatic or cystic defects of the mandible (five patients). In another five patients, the material was used to augment the atrophic anterior mandible in combination with the insertion of dental implants. Follow-up varied between 6 and 40 months (mean: 29 months). RESULTS: There was no inflammatory reaction surrounding the implanted material. There was no sign of infection in any of the patients and only one case of partial wound dehiscence with superficially exposed material. The defect fillings and augmentations were successful in all patients. None of the 19 dental implants which were inserted in combination with the material showed any sign of infection or loosening. Also, there was no loosening of the implants after loading (mean follow-up: 15 months). From the check-up radiographs, the material could be seen as a dense, radio-opaque structure. There were no material fractures or dislocations. Radiologically, the material seemed to be completely replaced by bony tissue after 30 months. CONCLUSION: Our 5-year clinical experience suggests that the material is a suitable bone mineral substitute for cranio-maxillofacial surgery especially for moderate-sized defects of the calvaria and forehead bone. It has advantages over preformed, solid bone substitute materials, and, due to its initial plasticity and eventual great compressive strength, it can also stabilize dental endosseous implants in the atrophic mandible.  相似文献   
90.
OBJECTIVE: Patients with non-small cell lung cancer (NSCLC) with metastases to ipsilateral mediastinal lymph nodes (N2) are an heterogeneous group of patients as regard to prognosis and treatment. Indication and timing of surgery remain controversial. The present study investigates the prognostic factors, in order to identify homogenous subgroups of patients. METHODS: Histologically proven N2-NSCLC patients, who underwent a complete surgical resection were retrospectively reviewed. Clinical and pathological features were reported and analyzed, and survival study was performed. RESULTS: One hundred eighty-three patients were analyzed. Overall 1.3 and 5 years survival rates were, respectively, 70, 35 and 20%, with a median survival time of 24 months. Univariate analysis showed a significant better prognosis for: incidental N2 respect to clinical N2 (5-years 35.4 vs 17.4%); single level lymph node involvement respect to multiple levels (5-years 23.8 vs 14.7%); metastases to superior mediastinal or aortic nodes respect to lower mediastinal nodes (5-years 32 and 24.3 vs 16.3%); right upper lobe tumors with superior mediastinal nodes and left upper lobe tumors with aortic nodes respect to lower lobes tumors with lower mediastinal nodes (5-years 31.8 and 26.9 vs 15.7%). Skip metastases had not a significant survival advantage respect to continuous lymphatic spread. N2 clinical status, the number of levels involved and the two specific patterns of lymphatic spread resulted significant prognostic factors at multivariate analysis. CONCLUSIONS: Clinical N2 status, number of lymph nodes levels involved and specific patterns of lymphatic spread identify homogenous subgroups of patients that can be proposed for different therapeutic strategies.  相似文献   
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