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1.
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   
2.
Cultured endothelial cells exposed to shear stresses in vitro undergo a reorganization of their F-actin-containing cytoskeletons which culminates in realignment with flow direction. Since a close transmembrane association exists between actin microfilaments and extracellular fibronectin, this study was undertaken to examine whether the actin reorganization induced by shear stress is accompanied by perturbations in the underlying fibronectin matrix. In a closed circulatory loop, bovine endothelial monolayers were exposed to steady, laminar flows corresponding to shear stress levels of 6 and 26 dynes/cm2 for 2, 6, 12, and 24 hours. The co-distribution of fibronectin and F-actin was determined in specimens which were double-labeled with antiserum to fibronectin and rhodamine phalloidin, respectively. Under the influence of shear stress, cells underwent coordinate shape changes resulting in varying degrees of alignment with flow direction. Reorientation at these shear stress levels was dependent on both the time of exposure and the magnitude of shear stress and was accompanied by a reorganization in cellular fibronectin and F-actin. In controls (no flow) correspondence between the two proteins was limited to similarly arranged, radial foci of fibronectin and F-actin filaments at the basal cell surfaces. In flow specimens, coincidence was detected only between occasional fibronectin fibrils and F-actin stress fibers. As a consequence of shear stress, fibronectin became more uniformly distributed beneath monolayers and frequently was organized into bands of densely packed fibrils. Despite this extensive reorganization, rearrangement of fibronectin did not result in the formation of identical, linear structures with F-.  相似文献   
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4.
The Behavioral Summarized Evaluation (BSE), is a 20-item paper- and-pencil rating scale specifically designed for the measurement of behavioral parameters which could be related to biological data in autistic children involved in educational programs, neurophysiological studies, and therapeutic trials. The development of the scale, the validity, and reliability studies are presented in this paper. The results suggest that the BSE is an acceptable tool for the assessment of autistic behaviors, easy to handle, and accessible to both professionals and paraprofessionals of the medico-educative staff. It is a useful addition to the bioclinical researcher's evaluation battery for bioclinical and therapeutic studies. However, more work is suggested to further investigate the psychometric properties of this behavior assessment instrument.This study was supported by CNRS, by INSERM U 316 Nervous System from the Foetus to the Child, Development, Circulation, Metabolism, L. Pourcelot, CNAMTS No. 2748/88, FRM 1986, Conseil Régional Région Centre, Contrat No.7.040.000, INSERM, and Fondation Langlois. The authors thank S. Lancrenon, Department of Biophysics and Biomathematics (J. Fermanian), C.H.U. Pitie-Salpetriere, Paris, for her helpful suggestions and assistance. They also thank Mrs. Barre and Miss Lioret for their technical work.  相似文献   
5.
Spatial discrimination of ibotenic acid-lesioned C57BL/6 (B6) and DBA/2 (D2) mice was tested in two-choice water maze and plus maze tasks. B6 but not D2 mice learned the spatial discrimination in the water maze, but strains did not differ in learning a spatial discrimination in the plus maze paradigm. Ibotenic acid lesions of the hippocampus impaired percentage correct choices in the water maze spatial discrimination task in B6 but not in D2 mice, the latter of which may have been due to a floor effect. Furthermore, lesioned mice were more thigmotaxic, the distance travelled until a choice was made was longer and animals made more errors of omission. Despite the poor performance during water maze acquisition, lesioned animals, as well as sham-lesioned D2 mice, eventually acquired some place response in the water maze, as was evident when the location of the platform was reversed. However, hippocampus-lesioned mice of both strains were impaired when tested in the plus maze spatial discrimination task. Thus, ibotenic acid-induced lesions of the hippocampus impair acquisition of spatial discrimination in mice. These deficits were strain-dependent and likely comprise impaired accuracy as well as changes in non-mnemonic types of behaviour. Importantly, lesions in both strains impaired spatial learning, and whether a deficit was seen in mice of the D2 strain seemed to depend on the demands of the task.  相似文献   
6.
The physiological roles and mechanisms of action of thrombopoietin (TPO) and its receptor c-Mpl have been studied through the analysis of mice genetically deficient in these molecules, as well as through the dissection of signaling events utilizing chimeric receptors. The evidence clearly demonstrates that the TPO/c-Mpl system provides dominant control in the regulation of megakaryocytopoiesis. The signaling mechanisms that underlie this process appear to be similar to those noted with other members of the hematopoietic cytokine and cytokine receptor families.  相似文献   
7.
Two types of 4 mm ID prostheses were studied in the carotid arteries of the dog. These were noncrimped polypropylene-supported filamentous velour knitted Dacron (PPSFV) and expanded polytetrafluoroethylene (e-PTFE, Gore-Tex). Thrombus-"Free" Surface TFS) areas and patency rates were determined at the end of the implant periods. One series of implants was subjected to controlled low flow rates for six hours; another was exposed to physiologic flow rates and observed at seven days, 14 days, and 12 weeks. At six hours the filamentous Dacron, preclotted according to a specific regimen utilizating heparin, performed as well as, and possibly better than, e-PTFE. The Gore-Tex developed surface coagulum in an irregular fashion which was related to graft wetting and blood soakage. Seven-day TFS scores and patency rates of the two graft types were comparable at physiologic flow rates. At two weeks, TFS scores and patency rates of the two graft types were comparable at physiologic flow rates. At two weeks, TFS scores and patency rates dropped. This was sufficiently marked in the case of e-PTFE that longer-term implants were not done. However, PPSFV grafts were implanted for 12 weeks, and all grafts examined at that time had closed. It appears that patency of 4 mm ID grafts of this construction will not be reliably attained in the dog carotid artery without the use of platelet-inhibitory drugs until complete healing has occurred.  相似文献   
8.
FL Porter  CM Wolf  J Gold  D Lotsoff  JP Miller 《Pediatrics》1997,100(4):626-632
BACKGROUND: Despite an increased awareness among clinicians regarding pain and pain management for infants undergoing surgery, pain associated with procedures performed outside the operating room may not be adequately managed. PURPOSE: To examine the beliefs and self-described behavior of physicians and nurses regarding the management of procedural pain in newborn infants. METHODS: A survey was distributed to 467 clinicians (nurses and physicians) working in 11 level II and 4 level III nurseries in a large metropolitan area. Respondents were asked to rate the painfulness of 12 common bedside nursery procedures and how often pharmacologic and nonpharmacologic (comfort) measures are currently used and should be used for those procedures. Demographic data were also collected. RESULTS: Surveys were completed by 374 clinicians (80% response rate). Physicians and nurses believe infants feel as much pain as adults and that 9 of the 12 listed procedures are moderately to very painful. Neither pharmacologic nor comfort measures are believed to be used frequently, even for the most painful procedures. Physicians and nurses believe both pharmacologic and comfort measures should be used more frequently, but nurses believe comfort measures should be used more frequently than do physicians. Beliefs about infant pain and procedural pain were related to pain management preferences. Physicians' but not nurses' ratings were associated with significant personal pain. CONCLUSIONS: Despite their beliefs that infants experience significant procedure-related pain, clinicians believe pain management for infants remains below optimal levels. Barriers to more consistent and effective pain management need to be identified and surmounted.  相似文献   
9.
Here we confirm and extend our previous studies demonstrating that the mutagenic potency of 1,2-dibromoethane (DBE) and dibromomethane (DBM) is markedly enhanced (not prevented) in bacteria expressing the O6- alkylguanine-DNA alkyltransferase (ATase) encoded by the Escherichia coli ogt gene. We demonstrate that, in close parallel with mutagenesis, the Ogt ATase sensitizes the bacteria to the lethal effects of these carcinogens, suggesting that one or more of the potentially mutagenic lesions induced by DBE and DBM in the presence of Ogt has additional lethal capacity. We further demonstrate that the sensitization to both lethality and mutagenesis by DBE and DBM is a property shared by other DNA alkyltransferases. This objective was accomplished by quantifying the induction of mutations and lethal events in ogt- ada- E. coli expressing an exogenous bacterial or mammalian ATase from a multicopy plasmid. Mammalian recombinant ATases enhanced the lethal and mutagenic actions of DBE and suppressed the lack of sensitivity of the vector- transformed bacteria to DBM. In most cases the order of effectiveness of the ATases ranked: murine > human > Ogt > rat. Further comparisons included the full-length Ada ATase from E. coli and a truncated Ada version (T-ada) that retains the O6-methylguanine binding domain of the protein. The full-length Ada ATase was effective in enhancing the lethality but not the mutagenicity induced by DBE and DBM. The T-ada ATase provided less sensitization than Ada to lethality by DBE, but of the three bacterial ATases T-ada yielded the highest sensitization to mutagenesis by this compound. T-ada and Ada ATases were in general less effective than the mammalian versions, with the exception of the rat recombinant ATase. The effectiveness of the different mammalian and bacterial ATases in promoting the deleterious actions of dibromoalkanes was compared with the effectiveness of these proteins in suppressing the lethal and mutagenic effects induced by N-nitroso-N-methylurea. The ability to sensitize E. coli to the lethal and mutagenic effects of DBE and DBM seems restricted to DNA alkyltransferase, since overexpression of thioredoxin (Trx) or glutaredoxin (Grx1) in ogt- ada- cells showed no effect, in spite of the reported potential of bioactive dihaloethane- derived species to alkylate Trx.   相似文献   
10.
Forty lower limb bypasses using arm veins were performed on 37 patients. The indications for surgery were limb threat in 50% of cases, graft failure in 33%, aneurysms in 10% and claudication in 7%. Saphenous veins were absent because of prior use in 73% of cases, and because they were unsuitable in 27%. A single vein was used in 48%, 2 veins in 40% and 3 veins in 12% of cases. Seventy-four per cent of cases had a single-vessel run-off below the distal anastomosis. Eighty-two per cent of the distal anastomoses were to infrapopliteal arteries. The primary and secondary rates of these 40 bypasses at a mean follow-up of 14 months (range 1-40 months) were 74% and 90%, respectively. Limb salvage was 94%. Peri-operative morbidity and mortality were 23% and 3%, respectively. The anatomical and technical aspects of harvesting arm veins are critical to the success of this procedure and will be emphasised. We have found arm veins to be a durable source of accessible autogenous grafts for lower limb revascularisation in the absence of suitable saphenous veins.  相似文献   
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