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101.
Bos JE van Erp J Groen EL van Veen HJ 《Journal of vestibular research : equilibrium & orientation》2005,15(3):149-160
This paper shows that tactile stimulation can override vestibular information regarding spinning sensations and eye movements. However, we conclude that the current data do not support the hypothesis that tactile stimulation controls eye movements directly. To this end, twenty-four subjects were passively disoriented by an abrupt stop after an increase in yaw velocity, about an Earth vertical axis, up to 120 degrees /s. Immediately thereafter, they had to actively maintain a stationary position despite a disturbance signal. Subjects wore a tactile display vest with 48 miniature vibrators, applied in different combinations with visual and vestibular stimuli. Their performance was quantified by RMS body velocity during self-control. Fast eye movement phases were analyzed by counting samples exceeding a velocity limit, slow phases by a novel method applying a first order model. Without tactile and visual information, subjects returned to a previous level of angular motion. Tactile stimulation decreased RMS self velocity considerably, though less than vision. No differences were observed between conditions in which the vest was active during the recovery phase only or during the disorienting phase as well. All effects of tactile stimulation found on the eye movement parameters could be explained by the vestibular stimulus. 相似文献
102.
Wit JM Finken MJ Rijken M Walenkamp MJ Oostdijk W Veen S 《Pediatric endocrinology reviews : PER》2005,3(1):52-3; author reply 54
103.
PURPOSE: To systematically review published data about the short- and long-term effects of exercise training and angioplasty on functional capacity and quality of life of patients with intermittent claudication. MATERIALS AND METHODS: Articles published between January 1980 and February 2003 were included if patients had intermittent claudication treated with exercise training or angioplasty and if both functional capacity and quality-of-life scores from Medical Outcomes Study 36-Item Short Form health survey were reported for at least 3 months of follow-up. Data were pooled by using a random effects model and weighted means. Pooled results were compared between the treatment groups by using the chi2 test and the Student t test (alpha = .05, two sided). RESULTS: In the analyses, five studies (202 patients) were included in the exercise group, and three studies (470 patients), in the angioplasty group. At 3 months of follow-up, the ankle-brachial index was significantly improved in the angioplasty group (mean change, 0.18; P < .01) but not in the exercise group (mean change, 0.01; P = .29). At 3 months, quality of life was significantly improved with regard to ratings of physical functioning and bodily pain in the exercise group (mean change, 18 and 10, respectively; P < .01) and physical role functioning in the angioplasty group (mean change, 30; P = .03). Mean change in ankle-brachial index significantly differed between the two treatment groups at 3 and 6 months (P < .01); mean change in quality-of-life scores did not. CONCLUSION: Improvement in quality of life was demonstrated after both exercise training and angioplasty, whereas functional capacity showed significant improvement after angioplasty. The ankle-brachial index significantly differed between the two treatment groups at 3 and 6 months, whereas the quality-of-life scores did not. 相似文献
104.
Drying effects in 14 natural lesions were studied with quantitative light-induced fluorescence and optical pathlength spectroscopy. Results were compared with clinical judgments of the lesion surface and microradiographical characterizations of the lesions. Relative fluorescence and average pathlength decreased as a function of drying time with a decay time ranging from 35.5 to <1 min. Depth and mineral loss correlated with average pathlength total changes (r = -0.79/-0.60, respectively) and poorly with total fluorescence changes (r approximately = 0.3). The decay time of the drying process for the relative fluorescence correlated well with a theoretical model based on water diffusion in lesion and surface layer, but only for large decay times. Clinical judgments could not be related to the surface layer properties or the changes in the average pathlength, but were weakly related to the changes in the relative fluorescence. We conclude that (i) fluorescence effects are mostly due to the screening by the lesion of the fluorescence from the dentin and enamel-dentin junction; (ii) water evaporation in lesions conforms to the diffusion laws only in large lesions with low surface layer penetrability; (iii) the evaporation process is controlled by the surface layer only for small surface penetrabilities (approximately 0.1 vol% microm(-1)). 相似文献
105.
Pijnenborg JM Dam-de Veen GC de Haan J van Engeland M Groothuis PG 《Gynecologic oncology》2004,94(2):550-559
OBJECTIVE: To investigate whether defective DNA mismatch repair (MMR) defines a subgroup at risk for recurrence in sporadic endometrial carcinoma patients. METHODS: Primary tumors from 44 patients with recurrent stage I endometrial carcinoma were compared after matching, with tumors of 44 patients being free of recurrence for minimal 3 years. Paraffin-embedded primary tumors (n = 88) and recurrent tumors (n = 32) were subjected to immunohistochemical analysis for hMSH2 and hMLH1 expression. Subsequently, a staining index (SI = 0-9) was calculated based on staining intensity and quantity. DNA was extracted from paraffin-embedded tissues, and promoter methylation of hMLH1 was determined by nested methylation-specific PCR (MSP). Microsatellite instability (MSI) was assessed by BAT-26 or BAT-25. RESULTS: Low hMSH2 expression was observed in 2% of primary tumors of control patients without recurrence, 14% of primary tumors of patients with recurrence, and 0% of recurrent tumors. Low hMLH1 expression was observed in 32%, 19%, and 22%, respectively. hMLH1 gene promoter methylation was detected in 50%, 47%, and 32%, and MSI was found in 16%, 14%, and 30%, respectively. No significant differences were found between primary tumors of patients with and without recurrence with respect to hMSH2 and hMLH1 expression, hMLH1 promoter methylation, and MSI. When primary and recurrent tumors were compared, there was an increased correlation of hMLH1 methylation with low hMLH1 expression and MSI in recurrent tumors. CONCLUSION: MSI, hMLH1 promoter methylation, and the expression of hMLH1 and hMSH2 are not predictive for the development of recurrent stage I endometrial carcinoma. In the progression of tumor, "de novo" hMLH1 methylation rarely occurs, instead there is further derailment of the MMR pathway in affected tumors. 相似文献
106.
Reesink K Dekker A van der Nagel T Blom H Soemers C Geskes G Maessen J van der Veen E 《Artificial organs》2004,28(10):933-939
Right-sided circulatory failure (RSCF) is a serious complication in 15-30% of patients receiving a left ventricular assist device (LVAD). It is hypothesized that left ventricular support which lacks physiologic properties predisposes to RSCF. An integral computer simulation and experimental validation protocol was performed. The results suggest that with conventional insensitive left ventricular support right-sided circulatory function is compromised, which may form a substrate for the onset or progress of RSCF. Feedback control of the LVAD could provide a means to counter this problem. A control concept for the LVAD which aims to preserve right-sided circulatory function, while supporting peripheral perfusion, is proposed 相似文献
107.
Context During 1999 and 2000, approximately 10 million people were affected by famine in Ethiopia. Results of nutrition assessments and surveys conducted by humanitarian organizations were used by donors and government agencies to determine needs for food aid and to make other decisions on geographic allocation of limited resources; however, accurate results might have been hampered by methodological errors. Objectives To identify common methodological errors in nutrition assessments and surveys and to provide practical recommendations for improvement. Design and Setting Nutrition assessments and surveys (n = 125) conducted by 14 nongovernmental organizations (NGOs) in 54 woredas (districts) in Ethiopia from May 1, 1999, through July 31, 2000. Surveys were ranked as valid and precise according to 5 criteria: use of population proportional to size sampling, sample size, number of clusters, number of children per cluster, and use of weight-for-height index. Main Outcome Measures Number and proportion of surveys that used standard, internationally accepted methods and reported valid and precise results. Results Fifty-eight of the 125 surveys (46%) were not intended to be standard 30 x 30 cluster surveys. Of the remaining 67 surveys, 6 (9%) met predetermined criteria for validity and precision. All 67 used the anthropometric index of weight-for-height, with 58 (87%) reporting z scores. Fifty-four (81%) used nonrandom sampling without consideration of population size and 6 (9%) had sample sizes of fewer than 500 persons. Conclusions Major methodological errors were identified among 30 x 30 cluster surveys designed to measure acute malnutrition prevalence in Ethiopia during the famine of 1999-2000. Donor agencies and NGOs should be educated about the need for improved quality of nutrition assessments and their essential role in directing allocation of scarce food resources. 相似文献
108.
Bouma AW van Dam B Meynaar IA Peltenburg HG Walenbergh-van Veen MC 《Nederlands tijdschrift voor geneeskunde》2004,148(33):1642-1645
A 44-year-old female was found comatose after attempting suicide. Toxicological screening showed phenobarbital intoxication. The patient was treated symptomatically. After ten days her serum level of phenobarbital still had not decreased and she was not clinically recovered. The patient was transferred to another hospital for hemoperfusion to decrease the level of phenobarbital. After hemoperfusion the level of phenobarbital dropped significantly and the patient recovered neurologically. Phenobarbital has a long elimination half-life and for this reason it is advisable to use means to accelerate clearance until the clinical condition of the patient shows improvement. Multiple-dose activated charcoal effects the elimination of phenobarbital. If elimination needs to be speeded up, then hemoperfusion can be considered. If this technique is unavailable, hemodialysis is a good alternative. 相似文献
109.
For tissue engineering of autologous cartilage, cell expansion is needed to obtain the cell numbers required. Standard expansion media contain bovine serum. This has several disadvantages, that is, the risk of transmitting diseases and serum-batch variations. The aim of this study was to find a serum-free medium with at least the same potential to expand cell numbers as serum-containing media. Ear chondrocytes of three young children were expanded in either serum-containing medium (SCM; DMEM with 10% fetal calf serum) or serum-free medium (SFM; DMEM with ITS+) supplemented with 5 or 100 ng/mL fibroblast growth factor-2 (FGF2). To promote cell adherence onto the culture flask, the serum-free conditions were cultured with 10% serum for 1 day after each trypsinization. After the fourth passage, the chondrocytes were encapsuled in alginate beads and redifferentiated in a SFM (DMEM with ITS+, hydrocortisone, and L-ascorbic acid) supplemented with 10 ng/mL IGF-I and 10 ng/mL TGFbeta-2. Results showed that expansion in SFM with 100 ng/mL FGF2 was comparable to expansion in SCM. Redifferentiation with SFM with IGF-I and TGFbeta-2 showed high collagen type II expression and high GAG/DNA production regardless of which expansion medium had been used. However, chondrocytes expanded in SFM with 100 ng/mL FGF2 resulted in less positive cells for collagen type I and 11-fibrau (a fibroblast membrane marker). The present study shows that it is possible to use serum-free medium for tissue engineering of cartilage. Expansion of immature ear chondrocytes in SFM supplemented with high-concentration FGF2 resulted in high cell numbers, which in addition had better redifferentiation capacity than cells expanded in medium with 10% serum. 相似文献
110.
Optimal camera and illumination angulations for detection of interproximal caries using quantitative light-induced fluorescence 总被引:2,自引:0,他引:2
The aim of the study was to find the optimal illumination and camera angulations for interproximal use of quantitative light-induced fluorescence (QLF). A multiaxis optical bench was developed and interproximal tooth assemblies were investigated using a modified version of QLF. Extracted human premolars without caries (n = 8) and with interproximal D1, D2 and D3 caries (n = 20) were selected. Tooth-pair models without caries and with interproximal caries of matching size, location, and shape were imaged with varying camera and illumination directions from buccal (0 degrees) to occlusal (90 degrees) to lingual (180 degrees) in steps of 30 degrees using a PC and framegrabber and examined for observed presence. Interproximal lesions could be detected in all teeth, but observed presence was dependent on camera angulation (p < 0.05), rather than on illumination angulation (p = 0.32). No caries could be detected with the camera in the 90 degree position. 相似文献