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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
Alexander Dullenkopf Goran Lamesic Andreas Gerber Markus Weiss 《Journal canadien d'anesthésie》2003,50(5):507-510
PURPOSE: A simple technical solution is presented to provide video transmission from the tip of a Bullard laryngoscope to a bedside video display, while the operator is still able to look through the viewing ocular of the Bullard laryngoscope during tracheal intubation. EQUIPMENT: This is achieved by insertion of an ultrathin fibreoptic video-endoscopic system into the working channel of the Bullard laryngoscope. Thereby the view from the distal blade tip is transmitted to a bedside monitor, without interfering with the use of the Bullards laryngoscope's original eyepiece. The presented technical solution allows video transmission without considerable additional weight normally associated with attaching video endoscopy cameras, light and camera cables to endoscopic devices. Thus, the Bullard laryngoscope remains lightweight and easy to maneuver. A screw-threaded adapter with a side-port is proposed to prevent displacement of the fibreoptic cable while still allowing application of oxygen. CONCLUSION: Experience and skills with tracheal intubation using the presented video-enhanced Bullard laryngoscope can be achieved in the originally intended way, while the supervisor or attending viewers can follow the tracheal intubation procedure on the video display. 相似文献
32.
Normative values of bone parameters of children and adolescents using digital computer-assisted radiogrammetry (DXR). 总被引:2,自引:0,他引:2
Ansgar Malich Martin G Freesmeyer Hans-Joachim Mentzel Dieter Sauner Joachim Boettcher Alexander Petrovitch Werner Behrendt Werner A Kaiser 《Journal of clinical densitometry》2003,6(2):103-111
PURPOSE: To verify whether estimation of bone mineral density (BMD) using digital X-ray radiogrammetry (DXR) is possible on children and to determine normative values of both such a DXR-BMD estimate and a corresponding metacarpal index (DXR-MCI) on. PATIENTS AND METHODS: In retrospect, X-rays were selected of the hands of 200 healthy Caucasian children (120 boys and 80 girls, aged 4-18 yr). The involved children were selected among a larger group of children submitted to the surgical department of our institute for evaluation of a suspected fracture after an occurred trauma. All children with a verified fracture or a chronic bone-related disease, including bone age retardation or acceleration, were excluded from the study. Furthermore, only conventional X-rays with the same film and capture parameters were included. The images were scanned and analyzed using the Pronosco X-posure system V.2 (Sectra Pronosco, Denmark). DXR-BMD, DXR-MCI, and a porosity index (DXR-PI) were automatically calculated using the midshafts of the metacarpals II-IV. Mean values of DXR-BMD and DXR-MCI were calculated separately for girls and boys in 2-yr intervals. RESULTS: In the present study the system has been demonstrated to be capable of calculating DXR-BMD from conventional X-rays of the hand from children down to approx 6 yr of age. This ability depended somewhat on the diameter and the length of the involved metacarpals. The success rate was higher for large bones than for small bones. The system succeeded in analyzing the images of 110 boys and 68 girls. Values of DXR-BMD were observed to increase with age from 0.40 g/cm2 to 0.62 g/cm2 in the male group and from 0.39 g/cm2 to 0.54 g/cm2 in the female group. Girls aged 11-12 yr had a higher DXR-BMD than did boys, corresponding to the earlier entry to puberty of girls. Standard deviations (SDs) reached values of up to 0.05 g/cm2. DXR-MCI increased with age from 0.36 to 0.47 for boys and from 0.34 to 0.49 for girls with a maximum SD of 0.06. The correlation between DXR-BMD and age was r=0.83 and r=0.84 for boys and girls, respectively. The corresponding correlations for DXR-MCI was lower, with observed correlations of r=0.63 (boys) and r=0.68 (girls), respectively, with p<0.01 in all cases. The DXR-PI did not reveal a significant correlation to age (r=-0.31 and r=0.04. respectively) and showed SDs marginally higher than the calculated mean values. CONCLUSION: The newly available DXR-methodology seems to offer the ability to determine DXR-BMD and DXR-MCI in children starting with a bone age of 6. This possibility may be of special relevance for children suffering from chronic bone diseases that require repeated X-rays of the hand (e.g. to determine bone age). The acquired normative data suggest that the measurements are of clinical value owing to low age-dependent variability (SDs) relative to an observed high increase with age. The clinical value of the porosity index (DXR-PI) remains uncertain and is limited owing to a high inter-individual variability. 相似文献
33.
34.
Martin Haupt Alexander Kurz Stefan Pollmann Barbara Romero 《Journal of neurology》1992,239(5):248-250
Summary Ninety outpatients with Alzheimer's disease according to ICD-10 diagnostic draft criteria were studied to test the hypothesis that cases with a familial aggregation are different from cases without such an aggregation with respect to cognitive impairment. In all cases the diagnosis of Alzheimer's disease was confirmed by prospective observation within 12 months of initial evaluation. Patients were divided into two groups: one consisting of 23 patients with a familial aggregation, the other consisting of 67 patients without secondary cases among first-degree relatives. By means oft-tests differences in impairment of cognitive functions between the groups were calculated. The results did not yield statistically significant differences between the groups for any of the neuropsychologically investigated cognitive deficits. Thus the hypothesis that the presence of a familial aggregation may lead to a distinct phenotype in Alzheimer's disease was not confirmed. 相似文献
35.
Henryk J Salacinski Nigel R Tai Robert J Carson Alan Edwards George Hamilton Alexander M Seifalian 《Journal of biomedical materials research》2002,59(2):207-218
Poly(ester)urethane and poly(ether)urethane vascular grafts fail in vivo because of hydrolytic and oxidative degradative mechanisms. Studies have shown that poly(carbonate)urethanes have enhanced resistance. There is still a need for a viable, nonrigid, small-diameter, synthetic vascular graft. In this study, we sought to confirm this by exposing a novel formulation of compliant poly(carbonate-urea)urethane (CPU) manufactured by an innovative process, resulting in a stress-free. Small-diameter prosthesis, and a conventional poly(ether)urethane Pulse-Tec graft known to readily undergo oxidation in a variety of degradative solutions, and we assessed them for the development of oxidative and hydrolytic degradation, changes in elastic properties, and chemical stability. To simulate the in vivo environment, we used buffered solutions of phospholipase A(2) and cholesterol esterase; solutions of H(2)O(2)/CoCl(2), t-butyl peroxide/CoCl(2) (t-but/CoCl(2)), and glutathione/t-butyl peroxide/CoCl(2) (Glut/t-but/CoCl(2)); and plasma fractions I-IV, which were derived from fresh human plasma centrifuged in poly(ethylene glycol). To act as a negative control, both graft types were incubated in distilled water. Samples of both graft types (100 mm with a 5.0-mm inner diameter) were incubated in these solutions at 37 degrees C for 70 days before environmental scanning electron microscopy, radial tensile strength and quality control, gel permeation chromatography, and in vitro compliance assessments were performed. Oxidative degradation was ascertained from significant changes in molecular weight with respect to a control on all Pulse-Tec grafts treated with t-but/CoCl(2), Glut/t-but/CoCl(2), and plasma fractions I-III. Pulse-Tec grafts exposed to the H(2)O(2)/CoCl(2) mixture had significantly greater compliance than controls incubated in distilled water (p < 0.001 at 50 mmHg). No changes in molecular weight with respect to the control were observed for the CPU samples; only those immersed in t-but/CoCl(2) and Glut/t-but/CoCl(2) showed an 11% increase in molecular weight to 108,000. Only CPU grafts treated with the Glut/t-but/CoCl(2) mixture exhibited significantly greater compliance (p < 0.05 at 50 mmHg). Overall, results from this study indicate that CPU presents a far greater chemical stability than poly(ether)-urethane grafts do. 相似文献
36.
37.
Prodromal frontal/executive dysfunction predicts incident dementia in Parkinson's disease. 总被引:2,自引:0,他引:2
Steven Paul Woods Alexander I Tr?ster 《Journal of the International Neuropsychological Society》2003,9(1):17-24
To identify the cognitive characteristics predictive of incident dementia in Parkinson's disease (PD), we examined the baseline neuropsychological profiles of 18 initially non-demented patients with PD who met diagnostic criteria for dementia (PDD) at one-year follow-up. PDD participants' baseline neuropsychological test scores were compared to the baseline performance of 18 patients with PD who did not meet criteria for dementia at one-year follow-up (PDND) and 18 normal controls (NC). The three groups were matched on baseline demographic and disease variables. Relative to the PDND group, the incident PDD participants demonstrated significantly poorer performance on digits backward (Wechsler Memory Scale-Revised), word list learning and recognition (California Verbal Learning Test), and perseverative errors on the Wisconsin Card Sorting Test. Each of these baseline neuropsychological variables exhibited adequate diagnostic classification accuracy in predicting PDD and PDND group membership at follow-up. These results suggest that subtle frontal/executive dysfunction is evident during the immediate PDD prodrome and may be of prognostic value in identifying PD patients at risk for dementia. Accordingly, neuropsychological evaluation may facilitate early identification of PDD and thereby inform appropriate dispositional planning. 相似文献
38.
Application of attachment theory to the study of sexual abuse. 总被引:1,自引:0,他引:1
P C Alexander 《Journal of consulting and clinical psychology》1992,60(2):185-195
Research on sexual abuse frequently fails to address the influence of the family as a risk factor for the onset of all kinds of sexual abuse and as a mediator of its long-term effects. Attachment theory provides a useful conceptual framework for understanding the familial antecedents and long-term consequences of sexual abuse. Themes associated with insecure parent-child attachment (rejection, role reversal/parentification, and fear/unresolved trauma) are frequently found in the dynamics of families characterized by sexual abuse, and specific categories of sequelae are related to probable attachment experiences. Implications for intervention and research on sexual abuse are suggested. 相似文献
39.
40.
J B Sherman M A Alexander D Gomez M Kim P Marole 《Journal of community health nursing》1992,9(3):183-190
The purpose of this study was to implement and evaluate a program for obese school children. A pretest-posttest design was utilized. Data was collected related to weight status, skinfold measurements, self-esteem, and nutritional knowledge. A convenience sample of 26 children, in the fourth to sixth grades, completed this 9-week program. The results indicate that self-esteem increased significantly (p less than .001) between the pretest and posttest interval. Weight status and nutritional knowledge showed no improvement. Exercise was difficult to assess on self-report, therefore no conclusions were were drawn in relation to this variable. Future research will be directed toward refining this intervention program. 相似文献