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91.
Walhovd KB Fjell AM Reinvang I Lundervold A Fischl B Salat D Quinn BT Makris N Dale AM 《Neuropsychologia》2005,43(5):704-713
The rationale for the present study was to investigate the relationship between cortical volume, the latency of the ERP component P3a (as a measure of speed-of-processing), and performance intelligence (not adjusted for age differences). Seventy-one participants aged 20-88 years underwent a visual 3-stimuli oddball ERP task, an MRI-scan, and intelligence testing. P3a latency and cortical volume shared 9% variance (p<.05) and both were significantly related to performance intelligence (R2=.26 and .40, respectively). The amount of explained variance increased significantly (to R2=.51) when both measures were used as simultaneous predictors. When a path diagram was constructed including age as an exogenous variable, P3a latency and cortical volume both significantly predicted performance intelligence, but were no longer related to one another. The main conclusion from the study is that speed and size are complementary in prediction of performance intelligence, and the theoretical implications are discussed. 相似文献
92.
Abstract
Hangover headache has been focused upon in connection with the Vågå study of headache epidemiology, with 714 cases among 1122 dalesmen (64%). Most frequently the headache was global in location. It was more frequently located in the anterior (frontotemporal) than occipital area. A unilateral headache was present in only 3% of the dalesmen, many of whom were migraineurs. Headache seemed to be more intense in males than females. Headache usually seemed to be of a lower intensity than the pain of migraine, but higher than, or similar to, that of tension-type headache. The headache appeared late in the night/early morning hours, i. e., several hours after discontinuation of drinking. In most cases, headache stopped in the late morning hours, or at high noon, but it could even last until somewhat late in the afternoon; it rarely, if ever, exceeded 12 hours duration. Red wine seemed mostly to provoke headache the same evening (with traits similar to those of the spontaneously occurring headache attacks). Criteria for hangover headache are proposed. 相似文献
93.
Bronchoscopic surfactant administration preserves gas exchange and pulmonary compliance after single lung transplantation in dogs 总被引:3,自引:0,他引:3
Friedrich I Börgermann J Splittgerber FH Brinkmann M Reidemeister JC Silber RE Seeger W Schmidt R Günther A 《The Journal of thoracic and cardiovascular surgery》2004,127(2):335-343
BACKGROUND: Surfactant abnormalities have been implicated in reperfusion injury and respiratory failure in lung transplantation. METHODS: We investigated the efficacy of bronchoscopic administration of a bovine natural lung surfactant extract (Alveofact) to improve gas exchange and lung mechanics after heterologous left lung transplantation in foxhounds (+4 degrees C ischemia for 24 hours, conservation with Euro-Collins solution). Animals received either no surfactant therapy (untreated controls, n = 6) or 50 mg/kg body weight (prior to explantation, only graft) and 200 mg/kg body weight Alveofact (immediately after reperfusion, both lungs, n = 6). After lung transplantation, separate but synchronized ventilation of each lung was performed in a volume-controlled, pressure-limited mode for 12 hours, with the animals prone. Small catheters were inserted into the pulmonary veins of both the graft and the recipient's native lung for separate blood gas analysis. In the control group, marked protein leakage, influx of neutrophils into the alveolar space, and pulmonary edema formation (extravascular lung water; wet/dry ratio) were encountered in the transplanted lung but only to a very minor extent in the recipient's native lung. RESULTS: Lung compliance values and arterial oxygenation progressively deteriorated in the transplanted but not in the native lungs. Pulmonary hemodynamics did not change significantly. Surfactant administration did not significantly influence the development of reperfusion edema, protein leakage, and neutrophil influx into the grafts. However, surfactant restored the surface activity and the gas exchange (PaO2/FIO2 of 201.2 +/- 20.2 mm Hg vs 119.8 +/- 21.7 mm Hg in controls; P <.05) in the transplanted lungs, and compliance was markedly improved in the surfactant-treated animals (18.8 +/- 1.8 mL/mbar vs 11.5 +/- 1.6 mL/mbar in the controls; P <.05). CONCLUSION: Bronchoscopic surfactant administration does not prevent leukocyte influx or vascular leakage but does protect against respiratory failure and improves lung mechanics in single lung transplantation in dogs. 相似文献
94.
This article describes the spatial and temporal distribution of verotoxin-producing Escherichia coli among humans (EHEC) and cattle (VTEC) in Sweden, in order to evaluate relationships between the incidence of EHEC in humans, prevalence of VTEC O157 in livestock and agricultural structure by an ecological study. The spatial patterns of the distribution of human infections were described and compared with spatial patterns of occurrence in cattle, using a Geographic Information System (GIS). The findings implicate a concentration of human infection and cattle prevalence in the southwest of Sweden. The use of probability mapping confirmed unusual patterns of infection rates. The comparison of human and cattle infection indicated a spatial and statistical association. The correlation between variables of the agricultural structure and human EHEC incidence was high, indicating a significant statistical association of cattle and farm density with human infection. The explained variation of a multiple linear regression model was 0.56. 相似文献
95.
Christie SD Sadi D Mendez I 《The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques》2004,31(1):87-96
BACKGROUND: The role of neural transplantation as a restorative strategy for spinal cord injury continues to be intensely investigated. Ideally, the tissue source for transplantation must be readily available, free of disease and able to survive and mature following implantation into the adverse environment created by the injury. We have studied the use of a commercially available cell line of cultured human neurons (hNT neurons) as a tissue source for neural transplantation in spinal cord injury. METHODS: Following a left lateral thoracic hemisection, 54 immunosuppressed, female Wistar rats were randomly allocated into different treatment groups; hemisection only or hemisection and hNT cell transplantation (via a bridge, double or triple graft). Grafting occurred three days after spinal cord injury. After thirteen weeks the animals were sacrificed and tissue sections were stained with human neuron specific enolase and human specific neural cell adhesion molecule. RESULTS: Immunohistochemical evidence of graft survival was displayed in 66.7% of the surviving, grafted animals. Fibre outgrowth, greatest in the bridge and triple grafts, was observed in both rostral and caudal directions essentially bridging the lesion. Double grafts were smaller, displaying less fibre outgrowth, which did not cross the lesion. Long fibre outgrowth was evident up to 2 cm from the graft as assessed by tracing and immunohistochemical studies. CONCLUSIONS: Bridge and triple grafts displayed greater growth and enabled the hNT graft to essentially bridge the lesion. This suggests that hNT neurons have the potential to structurally reconnect the proximal and distal spinal cord across the region of injury. 相似文献
96.
97.
In the V?g? study of headache epidemiology, a search was made also for cluster headache. Of the available 18-65-year-old dalesmen, 1838 (88.6%) could be examined personally (O.S.) - 51.3% females and 48.7% males. Based on current International Headache Society criteria, cluster headache seemed to be present in seven dalesmen, one female and six males (corresponding to a total prevalence of 381 per 100 000; 95% confidence interval (CI) 153-783 per 100 000). Except for the female gender, the female case was fairly typical. In one case, there were short-lasting bouts ('minibouts'). It was felt that this also was a genuine case of cluster headache. If one excluded the latter case, there would be one female and five males [a prevalence of 106 per 100 000 for females, and 558 per 100 000 for males, giving a prevalence in the total population of 326 per 100 000 (95% CI 120-709 per 100 000)]. The confidence interval was considerable. This study therefore does not give a clear indication as to prevalence. 相似文献
98.
99.
The impact of the CYP2D6 polymorphism on haloperidol pharmacokinetics and on the outcome of haloperidol treatment 总被引:7,自引:0,他引:7
Brockmöller J Kirchheiner J Schmider J Walter S Sachse C Müller-Oerlinghausen B Roots I 《Clinical pharmacology and therapeutics》2002,72(4):438-452
OBJECTIVES: The genetically polymorphic enzyme cytochrome P450 (CYP) 2D6 contributes to the biotransformation of the antipsychotic drug haloperidol. The impact of the polymorphism on haloperidol pharmacokinetics, adverse events, and efficacy was prospectively evaluated under naturalistic conditions in 172 unselected psychiatric inpatients with acute psychotic symptoms. METHODS: Serum trough levels of haloperidol and reduced haloperidol of patients receiving clinically adjusted doses were analyzed on days 3, 14, and 28 after hospital admission. Adverse events such as extrapyramidal symptoms were assessed by standardized rating scales. Efficacy was documented by recording the change in positive and negative schizophrenic symptoms. These parameters were correlated with the CYP2D6 genotype determined by polymerase chain reaction analysis for alleles *1 to *15 and *17. RESULTS: The serum concentrations showed wide interindividual variation. Reduced haloperidol trough levels and haloperidol total clearance correlated significantly with the number of active CYP2D6 genes. In addition, body weight and smoking had significant effects on haloperidol kinetics, whereas age, gender, and comedication showed only slight effects. The ratings for pseudoparkinsonism were significantly higher in poor metabolizers of substrates of CYP2D6. On the other hand, there was a trend toward lower therapeutic efficacy with increasing number of active CYP2D6 genes. CONCLUSIONS: Treatment with haloperidol should be avoided in extremely slow and extremely rapid metabolizers of CYP2D6 substrates. Both genotyping and blood concentration measurement explained only a fraction of the adverse events; about 20 patients would have to be genotyped to achieve a significant benefit in 1 patient. It is interesting that genotyping was at least as good a predictor of adverse events as the measured drug concentrations. 相似文献
100.