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61.
Reductions in right prefrontal cerebral blood flow have been correlated with symptomatic improvement in depressed individuals receiving electroconvulsive therapy (ECT). Non-invasive near infrared spectroscopy has previously been shown to reliably measure changes in cerebral hemoglobin concentrations and oxygen saturation. In this study, we measured the concentration and oxygen saturation of hemoglobin on the right and left frontal brain regions of nine patients during right unilateral ECT. In all patients, we have found that the electrically induced seizure causes a stronger cerebral deoxygenation on the side ipsilateral to the electrical current (-21+/-5%) with respect to the contralateral side (-6+/-4%). On the brain side ipsilateral to the ECT electrical discharge, we have consistently observed a discharge-induced decrease in the total hemoglobin concentration, i.e. in the cerebral blood volume, by -7+/-3 microM, as opposed to an average increase by 6+/-3 microM on the contralateral side. The ipsilateral decrease in blood volume is assigned to a vascular constriction associated with the electrical discharge, as indicated by the observed decrease in cerebral oxy-hemoglobin concentration and minimal change in deoxy-hemoglobin concentration during the electrical discharge on the side of the discharge. These findings provide indications about the cerebral hemodynamic/metabolic mechanisms associated with ECT, and may lead to useful parameters to predict the individual clinical outcome of ECT.  相似文献   
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The anterior sacral meningocele is the congenital hernia of the thecal sac into the pelvis through a bone defect of the anterior wall of the sacrum. The association of anorectal anomaly, anterior sacral defect and presacral mass, known as Currarino's triad, can be diagnosed during the first decade of life in the eighty per cent of the cases However, in the incomplete syndrome, the symptoms appear in adults. In order to avoid late complications and due to the clear genetic origin of this uncommon pathology, the investigation of the family is of paramount importance for the early diagnosis and treatment. We review the literature and add two cases of anterior sacral meningocele with rectal fistula and incomplete Currarino's syndrome. In one of the cases the pathology is also present in another member of the same family and is complicated with meningitis. The importance of early diagnosis and treatment of these malformations and the need for fammily genetic investigation are discussed.  相似文献   
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BACKGROUND AND AIM OF THE STUDY: The study aim was to update the clinical analysis of hemodynamic performance, structural failure and survival in patients undergoing aortic valve replacement (AVR) with a composite aortic, aldehyde tanned, stentless porcine bioprosthesis. METHODS: Between January 1990 and March 2001, 247 patients underwent AVR with aortic stentless valves. Patient demographic and clinical analysis included age, sex, valve lesion, valve size, pre- and postoperative NYHA class, hospital morbidity, mortality, operative data and duration of hospitalization. RESULTS: Mean patient age was 47.3 years; 71% of patients were males, and 45% had aortic insufficiency. The incidence of rheumatic heart disease requiring surgery was 41.7%. In 23% of patients surgery was indicated due to aortic stented bioprosthetic dysfunction. Preoperatively, 81% of patients were in NYHA classes III and IV. Mean follow up was 5.9+/-2.8 years (range: 1 month to 11.4 years); total follow up was 1,392 patient-years (98% complete). The valve size used was < or =25 mm in 75.3% of patients. The mean intensive care unit stay was 2.6 days; mean hospital stay was 10.7 days. Hospital mortality was 4.0% and late death 6.1%. There were no valve-related deaths. Postoperatively, the mean aortic effective orifice area (EOA) was 1.71 cm2, the mean peak transvalvular gradient 17.1 mmHg, and the mean transvalvular gradient 9.0 mmHg; the left ventricular mass index (g/m2) was 174 and 117 before and after surgery respectively. The rate of leaflet tissue degeneration was 0.9%, and seen as mild by echocardiographic follow up. Actuarial survival at almost 12 years was 91%, and freedom from reoperations was approximately 99%. CONCLUSION: Patients with aortic stentless valves have hemodynamic benefits seen as larger aortic EOA, low transvalvular gradients, satisfactory left ventricular remodeling with significant reduction of left ventricular mass, low complication rate, low reoperation rate, lower leaflet tissue degeneration rate, and no valve-related mortality. A longer follow up is required to confirm these benefits.  相似文献   
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PURPOSE: Multiple myeloma is an incurable hematologic malignancy characterized by increased bone marrow angiogenesis and extensive lytic bone disease. We have previously shown that elevated levels of stromal-derived factor-1alpha (SDF-1alpha) in peripheral blood plasma are associated with osteolysis in multiple myeloma patients. We have now examined whether SDF-1alpha levels also correlate with angiogenesis. EXPERIMENTAL DESIGN: We examined the contribution of multiple myeloma plasma cell-derived SDF-1alpha in the stimulation of in vitro angiogenesis using a tube formation assay. We also collected trephine and peripheral blood plasma samples from patients with multiple myeloma to analyze microvessel density and SDF-1alpha levels, respectively. RESULTS: We show that multiple myeloma plasma cell line-derived conditioned medium containing SDF-1alpha stimulates in vitro angiogenesis. In addition, in a large cohort of patients with multiple myeloma and its precursor condition monoclonal gammopathy of undetermined significance, we confirm previous findings that plasma cell burden correlates with both angiogenesis and plasma levels of SDF-1alpha. We now extend these observations and show the novel finding that peripheral blood plasma levels of SDF-1alpha positively correlate with the degree of bone marrow angiogenesis in multiple myeloma and monoclonal gammopathy of undetermined significance patients. CONCLUSIONS: High levels of SDF-1alpha produced by multiple myeloma plasma cells promote osteolysis and bone marrow angiogenesis. Therefore, we propose that inhibition of SDF-1alpha may be an effective mechanism by which angiogenesis and osteolysis can be reduced in multiple myeloma patients.  相似文献   
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Background Persistent or recurrent macular-sparing subretinal fluid (SRF) can sometimes occur following scleral buckling procedures. Observation and reoperation have been used in the management of such cases. Demarcation laser therapy (DLT) has been used to treat macular-sparing retinal detachments in the context of cytomegalovirus retinitis and as primary treatment for selected rhegmatogenous retinal detachments. There are, however, scarce data in the literature regarding its use following primary scleral buckling procedures. The current study explores the use of DLT under the latter circumstances.Methods The medical records of all consecutive patients with persistent SRF sparing the macula following primary rhegmatogenous retinal detachment repair using a scleral buckling procedure were retrospectively reviewed. Only those patients in whom the breaks were localised to the area of indentation and, thus, seemed to be well supported by the buckle were included. Demographics, clinical characteristics of the retinal detachment prior to scleral buckling, extension of the residual SRF observed postoperatively, details of the laser procedure, anatomical and functional outcomes and complications were evaluated.Results Seven patients, all females, with a mean age of 47.9 years (range: 20–81) were included in the study. The retinal detachments were superior (n=3), inferior (n=3) and subtotal, affecting both superior and inferior retina (n=1). Scleral buckling procedures were used to treat the retinal detachments in all cases. Following demarcation laser therapy, the area of SRF remained stable in two patients, and flattened in four. In one patient, extension of SRF occurred requiring further surgery.Conclusions Demarcation laser therapy appears to be a reasonable option in the management of patients with persistent or recurrent SRF sparing the macula following scleral buckling surgery.The authors do not have any proprietary interests in the products or methods utilised in this study  相似文献   
67.
The ultrastructure of the dorsal column nucleus (DCN) has been investigated at the level of the obex region in normal and experimental toads. Large 'isolated' neurons (greater than 20 micrometer) and clusters of small neurons (less than 20 micrometer) have been identified in this region. Synaptic profiles have been classified into three types: large 'en passant' LR boutons, containing round synaptic vesicles and neurofilaments, small R boutons with round vesicles and F boutons with pleomorphic vesicles. The axon terminals exhibited synaptic contacts with cell somata, with dendrites of varying calibers and with other axons. The terminals involved in the axo-axonic contact were the F boutons which were presynaptic to the LR boutons, thus representing the morphological basis for presynaptic inhibition. Transection of the second dorsal root was performed in order to identify the terminals of the primary afferents to the DCN, after different survival periods (16 h--50 days). Only the LR boutons underwent degeneration, thus representing the central endings of the primary dorsal root afferents. The functional significance of these findings was discussed.  相似文献   
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The records of 190 consecutive patients referred to our department to be treated for small cell lung cancer were retrospectively evaluated, and the outcomes were compared on the basis of their first-line treatment. 113 patients were treated with 4-6 courses of cyclophosphamide, epidoxorubicin and etoposide (CEVP16), 77 with 4-6 courses of carboplatin and etoposide (CBE). 72 patients had limited disease and 118 extensive disease. Response rates were 58.4% for CEVP16 and 28.6% for CBE (p=0.0001), with no significant difference in the time to progression (255 vs 246 days, p=0.21). Overall survival was 334 days and 212 days, and the 1-year survival rate was 46% and 22.1%, respectively (p=0.0018). In patients with limited disease, overall survival was 434 days and 249 days (p=0.08) in both treatment group respectively and 281 and 208 days in those with extensive disease, respectively (p=0.02). No difference in side effects was observed between the two groups of patients. Our data suggest a role for anthracycline-containing regimens as first-line treatment of small cell lung cancer.  相似文献   
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