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31.
The authors present their first experience with laser interstitial thermotherapy, (ITT). Four patients with deep-seated non-infiltrative benign tumours (three astrocytomas, one oligodendrocytoma) underwent ITT. Previously, a stereotactic procedure had been performed to determine the exact location of the tumour, its spatial configuration and its histological diagnosis. The MRI controls confirmed the efficacy of hyperthermia on the tumour tissues. The authors discuss the possible ITT mechanisms. The indications of such laser ITT in neurosurgery should be enlarged to malignant tumours (gliomas, metastases) and to certain hypophyseal adenomas.  相似文献   
32.
PURPOSE: To explore maternal responsiveness in the first 2 to 4 months after delivery and to evaluate potential predictors of maternal responsiveness, including infant feeding, maternal characteristics, and demographic factors such as age, socioeconomic status, and educational level. DESIGN AND METHODS: A cross-sectional survey design was used to assess the variables of maternal responsiveness, feeding patterns, and maternal characteristics in a convenience sample of 177 mothers in the first 2 to 4 months after delivery. The 60-item self-report instrument included scales to measure maternal responsiveness, self-esteem, and satisfaction with life as well as infant feeding questions and sociodemographic items. An online data-collection strategy was used, resulting in participants from 41 U.S. states. FINDINGS: Multiple regression analysis showed that satisfaction with life, self-esteem, and number of children, but not breastfeeding, explained a significant portion of the variance in self-reported maternal responsiveness scores. In this analysis, sociodemographic variables such as age, education, income, and work status showed little or no relationship to maternal responsiveness scores. CONCLUSIONS: This study provides additional information about patterns of maternal behavior in the transition to motherhood and some of the variables that influence that transition. Satisfaction with life was a new predictor of maternal responsiveness. However, with only 15% of the variance explained by the predictors in this study, a large portion of the variance in maternal responsiveness remains unexplained. Further research in this area is needed.  相似文献   
33.
This investigation monitored the response of established contact lens wearers using contact lenses made from Filcon 4a 77% water-content material in three different thicknesses (0.08, 0.10 and 0.12 mm) over a 6-hour period of wear under adverse environmental conditions. The results obtained showed the following. (1) In accordance with previous studies carried out with lenses of similar water content, the present lenses produced corneal desiccation staining under the challenging conditions of use. However, the staining produced was similar for all three lens thicknesses tested. (2) Corneal desiccation staining was present despite the good and stable fitting characteristics observed during the study, confirming that mechanical trauma is not a necessary cause for soft-lens-induced desiccation staining. (3) Corneal desiccation staining was associated with a rapidly destabilizing pre-lens tear film (PLTF) and a thinning lipid layer. The initial break-up of the PLTF and corneal staining were recorded with a higher incidence in the vertical quadrants than in the horizontal quadrants. The PLTF is thinnest and most unstable at the tear prism margin border, hence least efficacious at preventing evaporation. Corneal desiccation staining may be due, at least partly, to excessive evaporation at the contact lens front surface.  相似文献   
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35.
Madreporic coral: a new bone graft substitute for cranial surgery   总被引:9,自引:0,他引:9  
Since 1985, the authors have been using madreporic coral fragments (genera Porites) as a bone graft substitute. Of the 167 coral grafts implanted, 150 were coral "corks" used to obliterate burr holes (diameter 10 mm), five were large implants (length 20 to 40 mm) to repair skull defects, and 12 were coral blocks to reconstruct the floor of the anterior cranial fossa. Previous experimental studies suggested that coral grafts would be well tolerated and become partially reossified as the calcific skeleton was resorbed. The authors describe their experience and detail the main biological properties of these materials, which appear to be very promising for use in cranial reconstructive surgery.  相似文献   
36.
The Infant Behavioral Summarized Evaluation (IBSE) is a rating scale adapted from the Behavioral Summarized Evaluation (BSE) and specifically related to the assessment of behaviors of young children having autistic disorders. Content validity and reliability studies described in the paper were made from behavior ratings of videotapes for 89 children aged from 6 to 48 months. Results show a significant group of 19 items including some characteristic early autistic behaviors (communicative and social abnormalities) and some that are less commonly described in the syndrome (attentional, perceptive, and adaptive disorders). The value of the use of this scale for clinicians and professionals involved in behavioral evaluations and treatment of young children with developmental disorders and the necessity for further psychometric investigations are discussed.This study was supported by INSERM U.316 Nervous System from the Foetus to the Child. Development, Circulation, Metabolism, L. Pourcelot, INSERM, Network INSERM No. 489001, Grant INSERM No. 911182 (D. Savrage) No. 911008 (L. Hameury) MRT. No. 9906 Fondation Langlois. Gratitude is expressed to Professor G. Lelord who initiated and supervised this study. The authors thank Professor J. Fermanian, Department of Biostatistics, CHU Necker, Paris, for his helpful suggestions and assistance. They also thank Dr. Larmande, Dr. Leddet, Dr. Glorion, and Dr. Garreau for their medical participation in the study and C. Richard, C. Fillatre, J. Rabant, and F. Etourneau for the psychological assessments of children. Special thanks to G. Calzas, M. Barré, A. Lardeux, and D. Lioret for their technical assistance.  相似文献   
37.
Auditory evoked responses (AER) were obtained from Cz and Fz in 30 adults (14 male, 16 female) from 20-80 years old. Sound bursts (1000 Hz-200 msec) of four different intensities were used. Peak to trough amplitudes of P1N1 and N1P2 and latencies of P1, N1 and P2 peaks were measured with increasing stimulus intensity and slopes of amplitude - intensity and latency - intensity curves were analysed for assessment of an age effect. The main result is that the increase in P1N1 amplitude with increasing stimulus intensity is more pronounced in older persons. Previous studies have established a negative correlation between the augmenting-reducing responses and HVA levels in the CSF (with lower amounts of HVA in the CSF of "augmenters"). Decreased dopamine metabolism in old subjects could account for our results, so further studies should focus on patients with pathological dopamine deficiencies.  相似文献   
38.
Brain-derived neurotrophic factor (BDNF) is involved in the differentiation and the survival of neurons. It has also been shown to be associated with the regrowth of neurons of damaged spinal cord and the modulation of ionic currents by acting on sodium channels and NMDA receptors through tyrosine kinase B (TrkB) receptors. We investigated the effects of BDNF on rhythm generation induced by disinhibition in dissociated cultures from embryonic rat spinal cord (E14), with extracellular multisite recordings (MultiElectrode Arrays, MEAs) or intracellular patch-clamp recordings. Exogenous BDNF had only minor effects on the bursting by increasing the activity during the burst. This increase of activity is suggested to be mediated by a potentiation of the postsynaptic NMDA receptors because it has been found that BDNF potentiates the NMDA-evoked depolarization in cultures incubated with BDNF for 10 min. Possible direct effects of BDNF on sodium channels were also investigated by local application of BDNF to the soma of patched neurons but no depolarization was observed. Long-term application of BDNF strongly decreased the activity during the burst and also the number of active electrodes, possibly due to a decrease in network density.  相似文献   
39.
The objective of radiotherapeutic management in esophageal cancer is to accomplish maximum tumor sterilization with minimal normal tissue damage. This sincere effort is most often countered by the differential in tumor dose response vs normal tissue tolerance. Intraluminal isotope radiation, with its inherent advantage of rapid dose falloff, spares the lungs, the spinal cord, and other vital structures, yet yields adequately high doses to esophageal tumor. Though in existence since the turn of the century, the method of intracavitary radium bougie application dropped out of favor due to technical difficulties imposed by the size of the radium source and radiation exposure to the personnel involved. The authors describe a simple “iridium 192 afterloading intraluminal technique” that eliminates technical problems and reduces radiation exposure considerably.  相似文献   
40.
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