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排序方式: 共有1351条查询结果,搜索用时 203 毫秒
51.
Is zinc deficiency a risk factor for atherosclerosis? 总被引:3,自引:0,他引:3
The development of atherosclerosis is influenced by genetic, lifestyle and nutritional risk factors. Zn and metallothionein deficiency can enhance oxidative-stress-related signalling processes in endothelial cells, and since changes in available plasma Zn may affect the Zn status of the endothelium, Zn deficiency could be a risk factor for IHD. Although the association of Zn with many proteins is essential for their function, three key signalling processes are highlighted as being principal targets for the effect of Zn deficiency: the activation of NF-kappaB, the activation of caspase enzymes and the signalling of NO. The need to develop a reliable indicator of Zn status is critical to any epidemiological approach for studying the relationship between Zn status and disease incidence. Studies using appropriate animal models and investigating how the plasma Zn pool influences endothelial intracellular labile Zn would be helpful in appreciating the importance of Zn deficiency in atherogenesis. 相似文献
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The present study analyzed the anatomical plasticity of serotonergic immunoreactive projections to external anal sphincter (EAS) motoneurons, and the behavioral plasticity of EAS reflexes, penile erection, and locomotion in rats with spinal contusion injury (SCI) or complete spinal cord transection (TX). Electromyographic activity of the EAS, penile erection latency, and BBB locomotor score exhibited parallel recovery over the 6-week recovery period after contusion SCI. This pattern of recovery was not observed in TX animals. While locomotor scores demonstrated a small increase after TX, erectile and anorectal function remained at abnormal levels established immediately after injury. Serotonergic immunofluorescent (5-HT-IF) staining at the lesion site identified a small number of fibers spared after SCI that may provide a substrate for functional recovery. Pixel density measurements of 5-HT-IF in the vicinity of retrogradely labeled EAS and unlabeled pudendal motoneurons necessary for penile erection provide indirect evidence of serotonergic sprouting that parallels the observed functional recovery in animals with SCI. No 5-HT-IF was detected caudal to the injury site in TX animals. These studies indicate: (1) lumbosacral eliminative and reproductive reflexes provide a valid means of studying the mechanisms of post-SCI plasticity; (2) the similar recovery curves suggest similar return of descending control, perhaps through sprouting of descending serotonergic fibers; (3) the observed deficits after TX likely represent the permanent removal of descending inhibition and reflect reorganization of segmental circuitry. 相似文献
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This study investigated the effects of sample size on the noise floor and distortion product otoacoustic emissions (DPOAEs) in 55 normal-hearing subjects as a function of intensity. More specifically, we investigated the effects of sample size (12-400 sweeps) as a function of intensity (L1 = L2 = 35, 45 and 55 dB SPL), firstly, on the identifiability of DPOAEs (2F1-F2), secondly, on the noise floor adjacent to DPOAEs, and thirdly, on the magnitude of DPOAEs centred around geometric means of 531 Hz, 1,000 Hz, 2,000 Hz and 4,000 Hz. Testing was conducted with a commercially available system for measuring DPOAEs (Grason-Stadler, GSI-60). A constant F2:F1 ratio of 1.21 was used. As sample size increased from 12 to 400 sweeps, the noise floors decreased by about 13 dB; this closely corresponds to the expected 15 dB reduction based on the square root rule of noise reduction. The highest noise floors were measured at 531 Hz and the lowest noise floors at 2,000 Hz and 4,000 Hz. Identifiability increased as intensity increased from 35 to 55 dB SPL and as sample size increased from 12 to 400 sweeps for all stimulus conditions. Mean DPOAEs for all frequencies (531-4,000 Hz) appeared to decrease as sample size increased, particularly at stimulus levels of 35 dB and 45 dB SPL. These results may be explained by a reduction in the noise levels within the bandwidth of the DPOAE bin. That is, the DPOAE bin is comprised of the DPOAE plus background noise and these two quantities are not separated within the measured bin. Because the magnitude of bin containing DPOAEs is critically dependent on sample size, clinicians should carefully document this variable when collecting normative data. Similarly, clinicians who compare the magnitude of their DPOAEs to published data should note the sample size employed. 相似文献
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Wiskin AE Beattie RM 《Journal of pediatric gastroenterology and nutrition》2008,47(5):672; autor reply 672-672; autor reply 673
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MacEntee MI Wyatt CC Beattie BL Paterson B Levy-Milne R McCandless L Kazanjian A 《Community dentistry and oral epidemiology》2007,35(1):25-34
OBJECTIVES: This randomized clinical trial aimed to assess the effectiveness of a pyramid-based education for improving the oral health of elders in long-term care (LTC) facilities. METHODS: Fourteen facilities matched for size were assigned randomly to an active or control group. At baseline in each facility, care-aides in the active group participated with a full-time nurse educator in a seminar about oral health care, and had unlimited access to the educator for oral health-related advice throughout the 3-month trial. Care-aides in the control group participated in a similar seminar with a dental hygienist but they received no additional advice. The residents in the facilities at baseline and after 3 months were examined clinically to measure their oral hygiene, gingival health, masticatory potential, Body Mass Index and Malnutrition Indicator Score, and asked to report on chewing difficulties. RESULTS: Clinical measures after 3 months were not significantly different from baseline in either group, indicating that education neither influenced the oral health nor the dental hygiene of the residents. CONCLUSIONS: A pyramid-based educational scheme with nurses and care-aides did not improve the oral health of frail elders in this urban sample of LTC facilities. 相似文献
59.
BACKGROUND AND PURPOSE: An instrument that provides valid measurements of satisfaction with physical therapy care for Spanish-speaking patients will enhance communication and ensure their representation in quality assurance analyses and research on health care disparities. The purpose of this investigation was to provide preliminary information on the factor structure, group- and individual-level reliability, and criterion-referenced validity of measurements obtained from a Spanish-language version of the MedRisk Instrument for Measuring Patient Satisfaction With Physical Therapy Care (MRPS). SUBJECTS: A total of 203 Spanish-speaking patients in the New York City area participated in this study. METHODS: Consenting subjects completed a 20-item MRPS after discharge from outpatient physical therapy care. Several translators performed "forward" and "backward" translation of the MRPS, followed by consensus agreement on item structure. Factor structure was investigated using item-correlation and exploratory factor analysis. Group-level reliability for single test administration was assessed using the Cronbach alpha, and individual-level reliability was assessed by calculating the standard error of the measure (SEM). Concurrent validity was tested by comparing the item scores and mean scores of factors to global measures of satisfaction. RESULTS: The means of individual item scores (1-5) ranged from 3.22 for "I did not wait too long" to 4.80 for "My therapist treated me respectfully." There were no sex-based differences in item scores. Exploratory factor analysis suggested a 2-factor solution: a 7-item "external" factor and a 3-item "internal" factor. The correlations (r) of the mean scores from these factors with the 2 global measures ranged from .59 to .82. The SEM was 0.16 for the internal factor and 0.25 for the external factor. DISCUSSION AND CONCLUSION: The underlying factor structure of the Spanish-language version of the MRPS was identical to the English-language version. Our findings provide preliminary support for the reliability and validity of measurements obtained from the Spanish-language version of the MRPS. Further study is needed to assess the stability of these findings in other samples. As with English-speaking patients, Spanish-speaking patient's satisfaction with physical therapy care is most strongly linked to the professional behavior of the clinician. 相似文献
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