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61.
Théberge J Al-Semaan Y Jensen JE Williamson PC Neufeld RW Menon RS Schaefer B Densmore M Drost DJ 《Psychiatry research》2004,132(1):33-39
This study used high-field magnetic resonance spectroscopy to examine the correlation of 1H and 31P metabolite levels in patients with schizophrenia and normal controls. 1H and 31P in vivo spectra were acquired successively from the left anterior cingulate and left thalamus of nine chronic schizophrenic patients and eight comparable healthy controls. A significant positive correlation between glutamine (Gln) and phosphoethanolamine (PEtn) was found in the left anterior cingulate of patients. In the left thalamus of patients, a significant negative correlation between N-acetylaspartate (NAA) and glycerophosphocholine (GroPCho) was found. No significant correlations were found in controls. The correlation between glutamine and phosphoethanolamine may reflect a link between neurotransmission alterations and membrane phospholipid metabolism alterations. The negative correlation between N-acetylaspartate and glycerophosphocholine may reflect the presence of neurodegeneration. 相似文献
62.
BACKGROUND: This study evaluates laser ablation of large polyps and cancer of the rectum in poor-risk surgical patients. METHODS: We performed a retrospective review of treatment of rectal lesions with the neodymium yttrium aluminium garnet (Nd:YAG) laser. Biopsy was performed before the first and subsequent therapies. Large lesions were initially debulked by diathermy snare. Biopsies were performed on suspicious areas at follow-up after completion of therapy. RESULTS: Three patients with unresectable rectal cancer had symptom control over a mean period of 15.7 months and 12 patients with large polyps over 60.6 months since the start of therapy. Indications in polyps were carpeting of the rectum (n = 3), proximity to sphincter (n = 1), or comorbidity (n = 8). No complication occurred; however, there was 1 treatment failure. None of the patients with polyps developed cancer during a mean follow-up interval of 14 months after final treatment. CONCLUSIONS: Outpatient laser therapy is safe, repeatable, and effective in the local control of rectal lesions. 相似文献
63.
Extracorporeal membrane oxygenation as a bridge to cardiac transplantation in a patient with cardiomyopathy and hemophilia A 总被引:1,自引:1,他引:0
Thiagarajan RR Roth SJ Margossian S Mackie AS Neufeld EJ Laussen PC Forbess JM Blume ED 《Intensive care medicine》2003,29(6):985-988
OBJECTIVE: To report the use of extracorporeal membrane oxygenation (ECMO) as a bridge to cardiac transplantation in a patient with hemophilia A and dilated cardiomyopathy. DESIGN: Case report. INTERVENTIONS AND RESULTS: During ECMO factor VIII concentrate was administered to maintain a factor VIII level close to 50% of normal control both to decrease the risk of bleeding and to allow standard anticoagulation with heparin. The patient developed an inhibitor to exogenous factor VIII during hospitalization, which was successfully managed with a high-dose continuous infusion of factor VIII during ECMO, the transplant operation, and the postoperative period. CONCLUSIONS: We report the successful use of ECMO as a bridge to cardiac transplantation in a patient with hemophilia A and low-level factor VIII inhibitors. 相似文献
64.
Experimental and clinical evidence for persistence of polyclonal Philadelphia chromosome negative (Ph-) progenitors in chronic myelogenous leukemia (CML) patients has provided the rationale for autologous transplantation. Clinical trials of autologous transplantation suggest that this procedure can induce cytogenetic remissions in a subset of patients and may be associated with longer-than-expected patient survival. Most autologous transplant recipients, however, continue to have evidence of persistent leukemia. Recent reports indicating that it is possible to collect sufficient numbers of Ph- peripheral blood stem cells for autologous transplantation from most patients in complete cytogenetic remission on imatinib treatment have rekindled interest in autologous transplantation in CML. Additional approaches to eliminate residual disease in autografts and to sustain cytogenetic response after transplantation, however, will be required to achieve long-term restoration of Ph- hematopoiesis. Several promising methods to improve purging of the autograft and for more effective elimination of residual leukemia are being explored. 相似文献
65.
Redox-cycling of anthracyclines by thioredoxin system: increased superoxide generation and DNA damage 总被引:1,自引:0,他引:1
Anthracyclines such as doxorubicin and daunomycin undergo bioreductive activation by redox-cycling, and this is associated with generation of reactive oxygen species. Toxicity of anthracyclines is attributed to DNA intercalation by an anthracycline semiquinone radical that is generated via redox-cycling. Flavoprotein enzymes catalyze the bioreductive activation of anthracyclines. Thioredoxin reductase (TR), which is also a flavoprotein enzyme, participates in bioreductive activation of anthracyclines. In the present study we showed that addition of E. coli thioredoxin (Trx) enhances the rate of superoxide production by E. coli TR in the presence of anthracyclines. The superoxide generated in this redox-cycling process induced DNA damage as determined by an in vitro plasmid DNA damage assay. In addition, Trx-SH enhanced the activity of cytochrome P450 reductase and the redox-cycling of anthracyclines independently of NADPH. Furthermore, when A549 cells were incubated with E. coli Trx followed by doxorubicin treatment, increased levels of ROS generation were observed. Taken together, these results show a novel property of the Trx system in bioreductive activation of anthracyclines. 相似文献
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Hsu S Ledbetter LS Krishnan RS Reed JA 《Journal of the American Academy of Dermatology》2003,48(4):638-9; author reply 639
70.
The aim of this study was the introduction of a new linear ventricular measurement which has a better correlation with ventricular volume than the commonly used linear measurements, especially in chronically shunted patients with small and/or asymmetrical ventricles. Ventricular volume, brain volume, Evans ratio, Schierman index, cella media index and frontal and occipital horn ratio were measured from CT scans of 57 shunted hydrocephalic patients and 20 normal control children. Four groups of patients were identified with regards to the ventricular size and symmetry (small, large, symmetrical and asymmetrical). A new linear measurement was defined as half of the ratio of the frontal and occipital ventricular width to that of the skull (frontal and occipital horn width ratio; FOHWR) and compared to other linear measurements in different patient groups. FOHWR showed better correlation with ventricular size and ventricular brain ratio than the ventricular linear measurements currently in use, especially in chronically shunted patients with small and/or asymmetrical ventricles. 相似文献