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BACKGROUND: As costs related to mechanical ventilation increase, clear indicators of patients' readiness to be weaned are needed. Research has not yet yielded a consensus on physiological variables that are consistent correlates of weaning outcomes. Subjective perceptions rarely have been examined for their contribution to successful weaning. OBJECTIVE: To explore the subjective perceptions of dyspnea, fatigue, and self-efficacy and selected physiological variables in patients being weaned from mechanical ventilation. METHODS: Data were collected prospectively on 68 patients being weaned from mechanical ventilation. Subjective perceptions were measured by using 3 visual analog scales; physiological variables were measured by using the Burns Weaning Assessment Program and a patient profile. Weaning outcomes were recorded 24 hours after data collection. RESULTS: Participants were primarily white women and required mechanical ventilation for a mean of less than 4 days. Participants reported mild dyspnea, moderate fatigue, and high weaning self-efficacy. High PaO2, low PaCO2, stable hemodynamic status, adequate cough and swallow reflexes, no metabolic changes, and no abdominal problems were associated with complete weaning (P = .05). Subjective perceptions were associated with physiological variables but not with weaning outcomes. CONCLUSIONS: Multidimensional assessment of both primary and secondary indicators of readiness to be weaned is necessary for timely, efficient weaning from mechanical ventilation. Primary assessments include physiological variables related to gas exchange, hemodynamic status, diaphragmatic expansion, and airway clearance. Secondary assessments include perceptions related to key physiological variables. Additional research is needed to determine the predictive value of physiological variables and perceptions of dyspnea, fatigue, and self-efficacy.  相似文献   
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Face perception plays a crucial role in primate social communication. We have investigated the pattern of eye movements produced by rhesus monkeys (Macaca mulatta) as they viewed images of faces. Eye positions were recorded accurately using implanted eye coils, while neutral upright, inverted and scrambled images of monkey and human faces were presented on a computer screen. The monkeys exhibited a similar eye scan pattern while viewing familiar and unfamiliar monkey face images, or while viewing monkey and human face images. No differences were observed in the distribution of viewing times, number of fixations, time into the trial of first saccade to local facial features, and the temporal and spatial characteristics of viewing patterns across the facial images. However, there was a greater probability of re-fixation of the eye region of unfamiliar faces during the first few seconds of the trial suggesting that the eyes are important for the initial encoding of identity. Indeed, the highest fixation density was found in the eye region of all the face images. The viewing duration and the number of fixations per image decreased when inverted or scrambled faces were presented. The eye region in these modified images remained the primary area of fixation. However, the number of fixations directed to the eyes decreased monotonically from the upright images through the inverted versions to the scrambled face images. Nonetheless, the eyes remain the most salient facial substructure regardless of the arrangement of other features, although the extent of salience which they attain may depend both on the low level properties of the eyes and on the global arrangement of facial features. Electronic Publication  相似文献   
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Hereditary hearing loss (HHL) is a very common disorder. When inherited in an autosomal recessive manner, it typically presents as an isolated finding. Interestingly and unexpectedly, in spite of extreme heterogeneity, mutations in one gene, GJB2, are the most common cause of congenital severe-to-profound deafness in many different populations. In this study, we assessed the contributions made by GJB2 mutations and chromosome 13 g.1777179_2085947del (the deletion more commonly known as del (GJB6-D13S1830) that includes a portion of GJB6 and is hereafter called Delta(GJB6-D13S1830)) to the autosomal recessive non-syndromic deafness (ARNSD) genetic load in Iran. Probands from 664 different nuclear families were investigated. GJB2-related deafness was found in 111 families (16.7%). The carrier frequency of the 35delG mutation showed a geographic variation that is supported by studies in neighboring countries. Delta(GJB6-D13S1830) was not found. Our prevalence data for GJB2-related deafness reveal a geographic pattern that mirrors the south-to-north European gradient and supports a founder effect in southeastern Europe.  相似文献   
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The present systematic review and meta‐analysis was conducted to investigate the effects of ginger supplementation on markers of inflammatory and oxidative stress. PubMed, Embase, Scopus, and Web of Science were systematically searched to identify relevant clinical trials evaluating the effects of ginger on serum CRP (C‐reactive protein), TNF‐α (tumor necrosis factor‐alpha), IL‐6 (interleukin‐6), PGE2 (prostaglandin E2), TAC (total antioxidant capacity), and MDA (malondialdehyde) from inception up to September 2019. Mean difference and 95% confidence intervals were pooled using a random‐effects model. Potential publication bias was assessed using visual inspection of funnel plot and Egger's weighted regression tests. After excluding irrelevant records, 20 full‐text articles that included 25 separate studies were included to the meta‐analysis. Pooled results of this study indicated a statistically significant effect of ginger on serum CRP, TNF‐α, IL‐6, TAC, and MDA levels following ginger supplementation in compared to the controls. Also, the effects of ginger on serum PGE2 was marginally significant. Moreover, the high heterogeneity was disappeared in subgroup analysis performed by age, duration, dosage, and quality. This current analysis indicates that ginger supplementation has a significant effects on serum inflammatory and oxidative stress markers.  相似文献   
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The purpose of the research was to introduce a procedure to derive a powder compression parameter (EM A) representing particle yield stress using an effective medium equation and to compare the EM A parameter with the Heckel compression parameter (1/K).  相似文献   
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