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1.
The root mean square successive difference (RMSSD) in heart period series is a time domain measure of heart period variability. The RMSSD is sensitive to high-frequency heart period fluctuations in the respiratory frequency range and has been used as an index of vagal cardiac control. By transfer function simulations, the RMSSD statistic is shown to represent a high-pass filter that effectively captures respiratory sinus arrhythmia but also passes lower frequency fluctuations that can include sympathetic influences. These simulations, together with analysis of actual heart period series, reveal that the RMSSD is biased by basal heart period. Although between-subjects levels of RMSSD covary highly with spectral estimates of high-frequency variability, within-subject RMSSD change scores account for only 50-60% of the variance in spectral estimates. The present findings raise caveats in the applications and interpretation of the RMSSD statistic.  相似文献   
2.
Cardiac responses to non-signal stimuli and to signal stimuli in a vigilance task were examined in children born with congenital heart defects (CHD), and in normal and attention deficit disordered (ADD) subjects. Overall task performance was lower in subjects with heart defects and in the ADD group. Cardiac measures revealed that normal children displayed significantly larger heart rate deceleration to the target stimuli than did either of the clinical groups. Moreover, although no group differences were observed in the cardiac response to non-signal auditory stimuli, exaggerated heart rate deceleration was observed to vibrotactile stimuli in both the clinical groups. Regression analyses revealed that the magnitude of the cardiac response to somatosensory stimuli was predictive of task performance (both within and between subject groups), with larger responses associated with higher error rates and lower perceptual sensitivity. Results were suggestive of a predictive relationship between somatosensory reactivity and neuropsychological maturation.  相似文献   
3.
We compared the efficacy of the Medoff sliding plate (MSP) with 3 other screw-plate systems for fixation of unstable intertrochanteric fractures in a randomized multicenter trial of 569 elderly patients. The MSP has biaxial dynamic capacity along both the neck and the shaft of the femur unlike the other systems, which lack dynamic capacity along the shaft. 268 fractures were operated on with the MSP, and 301 with the dynamic hip screw (DHS), with or without a trochanteric stabilizing plate (DHS/TSP) or with the dynamic condylar screw (DCS). The MSP had recently been shown to the surgeons.The patients in the groups were similar as regards age, domestic situation, preinjury walking ability and type of fracture. We followed the patients clinically and radiographically for at least 1 year. There was no significant difference in walking ability at follow-up or rate of return to home. Fixation failure occurred in 18/268 fractures operated on with the MSP, in 8/238 with the DHS, in 3/49 with the DHS/TSP and in 1/14 with the DCS. The difference in the rate of fixation failure was not statistically significant when the MSP group was compared to the 3 other groups. In 14 of the 18 fixation failures in the MSP group, the biaxial dynamic capacity of the MSP had not been used due to technical errors by surgeons, unfamiliar with the new method. No selection bias was found regarding fracture types in the 2 subgroups of patients with correct or inadequate biaxial dynamization. Extramedullary fixation of unstable intertrochanteric fractures with these implants showed a low failure rate. When using the MSP, biaxial dynamization must be correctly performed.  相似文献   
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There is extensive evidence for influence of gut microbiota on health. Exclusive enteral nutrition (EEN) possibly changes gut microbiota, but the exact pathophysiological role is unknown. EEN has been shown to have an anti-inflammatory effect in children with Mb Crohn, an inflammatory bowel disease. The intestinal tract is very scarcely studied in children with juvenile idiopathic arthritis (JIA), but data points to an immunologically important role. The aim of this study was to explore if EEN had any anti-inflammatory effect in children with JIA. The first patient enrolled in the study was followed for 1 year. She had onset of severe polyarticular disease at 3.2 years of age, negative in RF, anti-CCP, ANA, and HLA-B27. She was included in the study at 7.4 years of age. Exclusive enteral nutrition was given in two periods of almost 7 weeks each, several months apart, during the year of the study. Clinical and laboratory status were assessed before, during, and after treatment periods. In this patient, EEN had remarkable anti-inflammatory effect that was sustained for months after each of two separate treatment periods. Exclusive enteral nutrition is a possible anti-inflammatory treatment in patients with JIA, but to what extent EEN is effective in other children with JIA needs to be explored, as well as the possible pathophysiological role of EEN in those children.  相似文献   
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Oral health care has been shown to have low priority in nursing and has been only partly successful. To create more positive effects than those achieved through traditional oral health care education, this project tested an educational model for nursing staff personnel. In addition to traditional oral health care education, some of the nursing staff members passed an additional dental auscultation period and served as oral care aides. The aides were responsible for the oral health care of the residents at their nursing facilities (intervention group). The intervention nursing facilities were compared with facilities where nursing personnel only received a traditional oral health care education program. Assessments were made at baseline and at a 6-month follow-up. At follow-up it was shown that the nursing staff in the intervention group gave higher priority to the oral health care work than the nursing staff in the control group.  相似文献   
8.
BACKGROUND AND AIMS: Impaired mobility is one of the strongest predictors for falls in older people. We hypothesized that exercise as part of a fall prevention program would have positive effects, both short- and long-term, on gait, balance and strength in older people at high risk of falling and with varying levels of cognition, residing in residential care facilities. A secondary hypothesis was that these effects would be associated with a reduced risk of falling. METHODS: 187 out of all residents living in 9 facilities, > or =65 years of age were at high risk of falling. The facilities were cluster-randomized to fall intervention or usual care. The intervention program comprised: education, environment, individually designed exercise, drug review, post-fall assessments, aids, and hip protectors. Data were adjusted for baseline performance and clustering. RESULTS: At 11 weeks, positive intervention effects were found on independent ambulation (FAC, p=0.026), maximum gait speed (p=0.002), and step height (> or =10 cm, p<0.001), but not significantly on the Berg Balance Scale. At 9 months (long-term outcome), 3 intervention and 15 control residents had lost the ability to walk (p=0.001). Independent ambulation and maximum gait speed were maintained in the intervention group but deteriorated in the control group (p=0.001). Residents with both higher and lower cognition benefited in most outcome measures. No association was found between improved mobility and reduced risk of falling. CONCLUSIONS: Exercise, as part of a fall prevention program, appears to preserve the ability to walk, maintain gait speed, ambulate independently, and improve step height. Benefits were found in residents with both lower and higher cognitive impairment, but were not found to be associated with a reduced risk of falling.  相似文献   
9.
Circulating plasma adiponectin, an adipocyte-derived protein, has been shown to be decreased in obese subjects as well as in patients with type 2 diabetes and also in subjects who do not have diabetes, but are insulin resistant. We assessed the relationship between plasma levels of adiponectin, the metabolic syndrome and the occurrence of small dense LDL particles (pattern B) in 101 clinically healthy middle-aged subjects recruited from the general population. Low adiponectin levels were associated with the metabolic syndrome and low-density lipoprotein (LDL) particle size (r =.55, P <.001). The relationship between adiponectin and LDL particle size remained in a multiple regression model, in which adiponectin and total body fat explained 30% of the variability in LDL particle size. Furthermore, subjects in the lowest tertile of adiponectin had an increased risk of having pattern B (risk odds ratio [ROR] = 5.6). Because this was a cross-sectional study, no conclusions can be drawn about causality. This is the first population-based study in man demonstrating a relationship between small dense LDL particles and adiponectin.  相似文献   
10.
OBJECTIVE: To evaluate how heredity for psoriasis influences classification according to the International League of Associations for Rheumatology (ILAR). Heredity for psoriasis is currently both an exclusion and an inclusion criterion for different types of childhood arthritis according to ILAR classification criteria. METHODS: Twenty physicians in 5 Nordic countries prospectively collected data from the incident cases in their catchment areas over an 18 month period beginning July 1, 1997. Clinical and serological data from the first year of disease were collected. RESULTS: Of the 321 patients included who could be classified according to ILAR criteria for childhood arthritis, 50 (15.6%) patients were excluded from 55 classification events and fulfilled criteria for "other arthritis 1" i.e., did not fulfill criteria for any of the other classification categories, primarily because of heredity for psoriasis. If psoriasis in second degree relatives was disregarded as an exclusion criterion, only 8.7% of the patients remained in the "other arthritis 1" subgroup. For 20.6% of the whole group, heredity for psoriasis in a first or second degree relative (or both) and its distribution among arthritis subgroups did not differ except for juvenile psoriatic arthritis. CONCLUSION: We suggest that second degree heredity for psoriasis be withdrawn as an exclusion criterion from the ILAR criteria.  相似文献   
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