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51.
The present study examined sex differences in hemisphere preference (HP) assessed by the Preference Test (PT). This instrument is designed to measure the extent to which normal subjects rely on right-hemisphere or left-hemisphere cognition. Factor analysis on the total sample (N=1,057; 473 men and 584 women) revealed a clear two-factor structure (i.e., left-HP and right-HP), although separate analyses for men and women suggest that this structure is more straightforward in men than in women. The main differences between men and women have to do with PT items relevant to language abilities, where women tend to be more symmetrically distributed across the two factors. However, the frequency of right- and left-HP is similar in men and women and does not change for men when PT scores are recalculated after removal of unspecific items. Furthermore, once the items that assess verbal abilities were excluded, the corrected PT value for women showed higher right-HP. Our results provide some indications of a less pronounced lateralization of hemisphere-linked cognitive abilities in women.  相似文献   
52.
Summary Concentrations of the sulfur-containing amino acids methionine, homocysteic acid, cysteic acid and taurine were measured in brain structures of young and old Wistar rats in an attempt to etablish a possible link between the increase in oxidative stress with ageing and changes in tissue levels of these amino acids. Contrary to data reported by others, in all brain structures of young and old rats homocysteic acid levels could not be quantified. Compared with young rats, in old animals taurine and methionine concentrations significantly decreased in striatum and cortex; decreased taurine levels were also found in nucleus accumbens and cerebellum and lower concentrations of methionine were found in midbrain, hippocampus and pons-medulla. Cysteic acid levels either did not change or significantly increased in cortex and hippocampus. These results are discussed taking into account the biosynthesis of sulfur-containing amino acids in rat brain and the decrease in glutathione in relation to oxidative stress with ageing.Changes in aspartic acid, glutamic acid, serine, glutamine, glycine and GABA concentrations with ageing were also determined in the same brain structures and were in good agreement with those previously reportedAbbreviations H 2O2 hydrogen peroxide - MAO monoamine oxidase - GSHP glutathione peroxidase - PAPS 3-phosphoadenosine-5-phosphosulfate - OPA O-phthaldialdehyde - HPLC high performance liquid chromatography - Asp aspartic acid - CA cysteic acid - CSA cysteine sulfinic acid - Cys cysteine - GABA -aminobutyric acid - Gln glutamine - Glu glutamic acid - Gly glycine - HCA homocysteic acid - Met methionine - Ser serine - Tau taurine  相似文献   
53.
The aim of this study was the evaluation, in healthy subjects, of the renal functional reserve (RFR), that is, the GFR increase induced by a combined infusion of amino acids (AA) and dopamine (D), in conditions of extracellular volume depletion caused by diuretic administration. In particular, this study was undertaken: a) to evaluate whether and to which extent, AA + D can reverse the functional GFR impairment induced by salt depletion, without volume restoration; b) to study whether any relationship may be found between the GFR in normal condition (the so-called "resting" GFR), and/or the renal functional reserve and the GFR impairment induced by salt depletion, in order to understand the role of both "resting" GFR and RFR in the degree of renal dysfunction induced by salt depletion. In control conditions the i.v. infusion of AA + D significantly increased RPF (+ 41% vs. baseline period) with a mean absolute increase of 211 ml/min. A similar pattern was observed in GFR behavior (+31.5% with 34 ml/min of mean absolute increase). A significant inverse exponential relationship was observed between GFR before AA + D i.v. infusion ("resting" GFR) and renal functional reserve (P less than 0.05), suggesting that, in normal conditions, these inversely related parameters may widely vary according to the tone of the glomerular arterioles. Following salt depletion, we observed a variable degree of GFR impairment. Both GFR and RPF were significantly decreased (-25.9%, P less than 0.05 and -29%, P less than 0.05, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
54.
55.
Visual event-related potentials and spline map topography during a discriminative response task (DRT) were studied in 8 obsessive-compulsive disorder (OCD) patients without comorbidity for panic disorder or depression and in 12 age-matched controls. In the DRT task (like in a go/no-go task) the subject had to press a button when the target stimuli appeared and had to retain the response when the non-target stimulus appeared (vertical bars were intermixed with an equal probability of horizontals). OC patients had greater N1 latency than controls and their N1 and P3 amplitude was larger for the target stimuli, but not for non-target stimuli. In the normals, non-target stimuli (no-go task) produced a larger activation than target stimuli (go task). In the OCD patients the target stimuli produced the same large activation as the non-target. These findings are consistent with theories that consider OCD to be an attentional disorder deriving from a misallocating of cognitive resources. Moreover, spline map topography confirmed that P3 hyperactivation is localised principally on the frontal lobes.  相似文献   
56.
Rituximab for myasthenia gravis developing after bone marrow transplant   总被引:8,自引:0,他引:8  
Zaja F  Russo D  Fuga G  Perella G  Baccarani M 《Neurology》2000,55(7):1062-1063
  相似文献   
57.
The relationship between coercion strategies used by perpetrators of childhood sexual abuse (CSA) and elevations of CSA survivors on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) was investigated. Participants were 151 women survivors of CSA in outpatient treatment at a university-based community mental health center. Scores on the MMPI-2 clinical scales and the Keane posttraumatic stress disorder (PTSD) scale were examined. Main effects were found for promised or received rewards on several clinical scales and the PTSD scale of the MMPI-2, independent of the presence of force. Specifically, the presence of such rewards was associated with significantly higher levels of symptomatology on Paranoia (Pa), Psychasthenia (Pt), Schizophrenia (Sc), and PTSD (Pk). There were no main or interaction effects noted for the presence of actual or threatened force on any of the scales.  相似文献   
58.
PURPOSE: Imatinib (Glivec) is a potent inhibitor of bcr/abl, an oncogenic fusion protein that causes chronic myelogenous leukemia (CML). alpha1 acid glycoprotein (AGP) binds to imatinib with high affinity and inhibits imatinib activity in vitro and in vivo in an animal model. A pharmacokinetics analysis of imatinib was undertaken in CML patients. EXPERIMENTAL DESIGN: Imatinib plasma concentrations were measured in 19 CML patients treated with imatinib (400 or 600 mg/day). Five patients received a concomitant short-term course of clindamycin (CLI). RESULTS: A positive correlation between AGP and imatinib plasma levels was observed. CLI administration decreased imatinib plasma concentrations, evaluated as area under the curve (AUC) and peak concentrations (C(max)). The effects of a bolus of CLI was studied in three patients on imatinib 23 h after the last imatinib dose. Within 5-10 min in three of three cases, CLI caused a decrease in imatinib plasma concentrations of 2.6-, 2.7-, and 4.7-fold, respectively. In vitro experiments using fresh blasts from CML patients showed that AGP, at concentrations observed in the patients, decreased imatinib intracellular concentrations up to 10 times and blocked imatinib activity. The incubation with CLI restored imatinib intracellular concentrations and biological activity. CONCLUSION: AGP exerts significant effects of the pharmacokinetics, plasma concentrations, and intracellular distribution of imatinib in CML patients; these data indicate that plasma imatinib levels represent unreliable indicators of the cellular concentrations of this molecule.  相似文献   
59.
Background. Abnormalities of the pulmonary arteries following palliative or corrective surgery for tetralogy of Fallot (TOF) are common. Our purpose was to compare the usefulness of magnetic resonance imaging (MRI) and echocardiography in the post- operative evaluation of the pulmonary arteries in children with TOF. Objective. Our hypothesis was that MRI is more sensitive than echocardiography in the detection of branch pulmonary artery abnormalities in children with TOF. Materials and methods. Pulmonary artery MRI and echocardiography were performed in 20 children following palliative and/or corrective surgery for TOF. MRI and echocardiography were compared in their ability to detect abnormalities of the pulmonary arteries. Angiographic or surgical correlation was available in 15 children. A perfusion scan for confirmation of pulmonary artery patency was available in one additional child. Results. Abnormalities of the branch pulmonary arteries identified by MRI included: absence or occlusion (2), focal stenosis (15), hypoplasia (2), aneurysm (1), and non-confluence (1). Echocardiography could not adequately visualize the right and left branch pulmonary arteries in eight and ten children, respectively. Echocardiography missed stenosis in 13 branch pulmonary arteries, patency of hypoplastic pulmonary arteries in two children, non-confluence of the pulmonary arteries in one child, and a left pulmonary artery aneurysm in one child. Abnormalities identified by MRI were confirmed in 16 children by angiography, surgery or perfusion scan. Conclusion. MRI is more sensitive than echocardiography for the evaluation of branch pulmonary artery abnormalities in children following surgery for TOF. Received: 13 January 1997 Accepted: 31 July 1997  相似文献   
60.
This study examined whether the prevention of diabetes-related albuminuria by aminoguanidine (AG) or ramipril (RAM) may be mediated by a common post-glomerular basement membrane renal intracellular mechanism involving protein kinase C (PKC). The renal handling of albumin was examined over 24 weeks in control and streptozotocin (STZ)-induced diabetic rats. A radioimmunoassay (RIA) that measures intact albumin, and intravenously injected tritium-labeled rat serum albumin, was used to assess the proportion of intact albumin and albumin fragments in urine. Diabetes was induced in male Sprague-Dawley rats by the intravenous administration of STZ at a dose of 50 mg/kg. Age-matched control rats received buffer alone. Diabetes was characterized by an increase in blood glucose (>15 mmol/l), an increase in GHb (means at 24 weeks 29.3+/-1.1%; control 6.1+/-0.1%, P<0.005), an increase in glomerular filtration rate (GFR) (4.13+/-0.15 ml/min; control 3.54+/-0.19 ml/min, P<0.005), an increase in intact albumin excretion rate (expressed as geometric mean 11.64 times/divided by 2.11 mg/24 h; control 0.74 times/divided by 1.57 mg/24 h, P<0.005) as measured by RIA, and an increase in glomerular PKC activity (26.83+/-2.38 pmol x mg(-1) x min(-1); control 14.6+/-2.99 pmol x mg(-1) x min(-1), P<0.005). Treatment of diabetic rats with either AG or RAM prevented the rise in intact albuminuria and glomerular PKC activity. Renal lysosomal cathepsin activity decreased in diabetic rats and this was not prevented by AG or RAM. Neither drug affected glycemic control or GFR, but RAM reduced systolic blood pressure (BP), whereas AG did not. These data indicate that urinary excretion of intact albumin and albumin-derived fragments in diabetes may be modulated independently of glycemic control (AG and RAM) and systolic BP (RAM). While both drugs are known for their different mechanisms of action, the fact that both prevent diabetes-related increases in glomerular PKC activity and albuminuria supports the hypothesis that PKC plays a central role in the development of diabetic nephropathy.  相似文献   
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