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71.
Chromatopsia     
More than half of the cases with complaints of chromatopsia had recent-onset retinal pathology. Erythropsia due to bright (sun-)light is a relatively common finding in aphakia and pseudophakia. UV-coated intraocular lenses do not provide complete protection. Cerebrovascular chromatopsia usually occurs in transient attacks.  相似文献   
72.
Total radical trapping antioxidant potential (TRAP) and exercise   总被引:1,自引:0,他引:1  
The relationship between physical activity, physical fitness and total radical trapping antioxidant potential (TRAP) was examined in the Northern Ireland Health and Activity Survey. This was a cross-sectional population study (n = 1600) using a two-stage probability sample of the population. TRAP was calculated using the sum of the individual serum antioxidant concentrations (urate, protein thiols, ascorbate, alpha tocopherol and bilirubin) multiplied by their respective stoichiometric values. Physical fitness was determined by estimation of VO2max by extrapolation from submaximal oxygen uptake, and physical activity was recorded by computer-assisted interview. Mean serum TRAP concentrations were significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female smokers had significantly lower TRAP values than non-smokers (males p < 0.0001, females p = 0.02). In females, there was a positive relationship of TRAP with age (p < 0.001) and body mass index (p < 0.001) but a negative relationship with physical fitness (p < 0.05). The known beneficial effects of exercise and activity do not appear to be directly mediated through increased antioxidant status.   相似文献   
73.
The interaction of amitriptyline, doxepin, imipramine and their N-methyl quaternary derivatives with muscarinic receptors was investigated in the brain and heart. The potency of the tricyclic derivatives for inhibiting the binding of 11[[2-[(diethylamino) methyl]-1-piperidinyl]acetyl]-5,11-dihydro-6H-pyrido[2,3-b] [1,4] benzodiazepine-6-one to M2 muscarinic receptors in cerebral cortex was similar to that measured in competitive binding experiments with the nonselective muscarinic antagonist [3H]N-methylscopolamine in the corpus striatum and heart. Moreover, the tricyclic derivatives antagonized muscarinic receptor-mediated inhibition of adenylate cyclase activity with similar potency in the corpus striatum and heart, and there was good agreement between the affinities of the tricyclic derivatives when measured by radioligand binding and by antagonism of the adenylate cyclase response. Our results show that amitriptyline, doxepin and imipramine lack selectivity for subtypes of the muscarinic receptor.  相似文献   
74.
Understanding mechanisms and active ingredients of intervention is critical to training clinicians, particularly when interventions are transported from laboratories to communities. One promising active ingredient of parenting programs is clinicians’ in vivo feedback regarding parent–child interactions. The present study examined whether a form of in vivo feedback, in the moment commenting, predicted treatment retention and parent behavior change when the Attachment and Biobehavioral Catch-up (ABC) intervention was implemented in a community setting. Observational data were collected from 78 parent–child dyads (96% mothers; M age = 29 years; 81% minority; infants’ M age = 12 months; 90% minority) across 640 sessions conducted by 9 clinicians (100% female, M age = 39; 67% minority) in Hawaii. Parental behavior was assessed with a semistructured play task before and after intervention. Clinicians’ in-the-moment feedback to parents was assessed from intervention session videos. Clinicians’ frequency and quality of in-the-moment feedback predicted change in parental intrusiveness and sensitivity at posttreatment. Frequency of in-the-moment feedback also predicted likelihood of retention. Hierarchical linear modeling demonstrated strong support for these associations at the between-clinician level, and limited additional support at the within-clinician (i.e., between-case) level. Thus, a hypothesized active ingredient of treatment, in-the-moment feedback, predicted community-based ABC outcomes. The results complement lab-based evidence to suggest that in vivo feedback may be a mechanism of change in parenting interventions. Helping clinicians to provide frequent, high-quality in vivo feedback may improve parenting program outcomes in community settings.  相似文献   
75.
Playing a musical instrument at a professional level is a complex multimodal task requiring information integration between different brain regions supporting auditory, somatosensory, motor, and cognitive functions. These kinds of task‐specific activations are known to have a profound influence on both the functional and structural architecture of the human brain. However, until now, it is widely unknown whether this specific imprint of musical practice can still be detected during rest when no musical instrument is used. Therefore, we applied high‐density electroencephalography and evaluated whole‐brain functional connectivity as well as small‐world topologies (i.e., node degree) during resting state in a sample of 15 professional musicians and 15 nonmusicians. As expected, musicians demonstrate increased intra‐ and interhemispheric functional connectivity between those brain regions that are typically involved in music perception and production, such as the auditory, the sensorimotor, and prefrontal cortex as well as Broca's area. In addition, mean connectivity within this specific network was positively related to musical skill and the total number of training hours. Thus, we conclude that musical training distinctively shapes intrinsic functional network characteristics in such a manner that its signature can still be detected during a task‐free condition. Hum Brain Mapp 37:536–546, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
76.

Background

Myocardial injury after noncardiac surgery is common, although the exact pathophysiology is unknown. It is plausible that hypotension after surgery is relevant for the development of myocardial injury. The authors evaluated whether low mean arterial pressures (MAPs) after surgery are related to an increased incidence in postoperative cardiac-troponin elevation.

Methods

A prospective cohort of 2211 patients aged ≥60 yr, undergoing major or moderate noncardiac surgery in The Netherlands, was retrospectively analysed for the occurrence of postoperative cardiac-troponin elevation [high-sensitive troponin T (hsTnT) >14 ng L?1]. Blood pressures after surgery were recorded and divided into quartiles based on the lowest MAP prior to peak troponin recording. The association between MAP and extent of postoperative cardiac-troponin elevation was analysed.

Results

The patients were divided into quartiles based on their lowest MAP in the period preceding the peak hsTnT, ranging from a median of 62 in the lowest quartile to 94 in the highest quartile. Postoperative hsTnT elevation was present in 53.2% of the population. An association between MAP quartile and postoperative peak hsTnT was predominantly observed in the lowest quartile (P<0.001): median hsTnT 17.6 (10.3–37.3), 14.9 (9.4–24.6), 13.8 (9.1–22.5), and 14.0 (9.2–22.4). The multivariable logistic-regression analysis showed an increased risk for postoperative cardiac-troponin elevation with decreasing MAP thresholds.

Conclusions

Lower postoperative blood pressure is associated with an increased incidence of postoperative cardiac hsTnT elevation, irrespective of pre- and intraoperative variables.  相似文献   
77.

Background

Emerging evidence suggests that postoperative troponin release is a strong and independent predictor of short-term mortality. However, evaluating elevated troponins in patients with chronic kidney disease (CKD) is still controversial and is often disregarded. This study examines morbidity along with short- and long-term mortality risk associated with elevated high-sensitivity troponin T (hsTnT) in patients with different stages CKD undergoing noncardiac surgery.

Methods

This observational cohort comprised 3262 patients aged ≥60 yr who underwent noncardiac surgery. Postoperative hsTnT concentrations were divided into normal [<14 ng l?1 (reference)], low (14–49 ng l?1), moderate (50–149 ng l?1), and high (≥150 ng l?1) groups. A threshold of 50 ng l?1 was used to dichotomize hsTnT. The study endpoints were 30-day and long-term all-cause mortality, and postoperative myocardial infarction.

Results

Postoperative hsTnT was associated with a stepwise increase in 30-day and long-term mortality risk: low hsTnT adjusted hazard ratio (HR) 1.4 [95% confidence interval (CI): 1.1–1.7], moderate hsTnT adjusted HR 3.1 (95% CI: 2.3–4.3), high hsTnT adjusted HR 5.5 (95% CI: 3.6–8.4). Postoperative hsTnT ≥50 ng l?1 was associated with 30-day and long-term mortality risk for each stage of CKD. Elevated troponin concentrations in severe CKD (estimated glomerular filtration rate <30 mL min?1 1.73 m?2), however, did not predict short-term death.

Conclusions

Elevated postoperative hsTnT is associated with a dose-dependent increase in 30-day and long-term mortality risk in each stage of CKD with an estimated glomerular filtration rate ≥30 ml min?1 1.73 m?2.  相似文献   
78.
79.
80.
Lung injury after cardiac surgery is believed to result from cardiopulmonary bypass and its pro-inflammatory effects. To test this hypothesis, we compared the oxygenation ratios, extravascular lung water indices and systemic and pulmonary tumour necrosis factor alpha (TNF-α) and interleukin (IL)-8 at predetermined intervals in coronary artery surgery patients with or without cardiopulmonary bypass. No differences in oxygenation ratios or extravascular lung water indices were found. Serum values of TNF-α and IL-8 increased in both groups but were higher in the cardiopulmonary bypass group (end of surgery: mean (SD) TNF-α 3.68 (2.5) vs 2.20 (1.2) pg.ml−1 (p  =  0.043 (CI 0.05–2.9)) and mean (SD) IL-8 19.45 (10.8) vs 6.31 (5.3) pg.ml−1 (p  =  0.001 (CI 6.9–19.3)). In broncho-alveolar lavage fluid, TNF-α and IL-8 increased in both groups with no differences between the groups.  相似文献   
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