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991.
Ben Rattray Martin Thompson Patricia Ruell Corinne Caillaud 《European journal of applied physiology》2013,113(2):427-436
There is limited understanding of the mitochondrial adaptation following repeated eccentric exercise bouts, a model resulting in muscle adaptation known as the repeat bout effect. It was hypothesized that downhill training would reduce mitochondrial calcium content (MCC) post an acute eccentric bout with concurrent improvements in mitochondrial respiratory function. Thirty-four Sprague–Dawley rats were divided into four groups: control (N), control with acute eccentric exercise (N ecc), trained control (X) and trained with acute eccentric exercise (X ecc). Training for X and X ecc consisted of 30 min per day for five consecutive days of downhill treadmill running. The acute eccentric exercise bout was a ?14° treadmill exercise for 90 min performed 2 weeks after the training period. Animals were killed 48 h post-exercise. Isolated mitochondria from the red quadriceps allowed for the measure of mitochondrial respiratory indices and MCC. Calpain activity and heat shock protein 72 expression (HSP72) were also measured. MCC dramatically increased following the acute bout of eccentric exercise in N ecc (p < 0.001), but did not change in X ecc. Mitochondrial respiratory function tended to be slightly depressed in N ecc (state 3 respiration, p = 0.053; respiratory control ratio, p = 0.098) and unaltered in X ecc. Previous training altered the calpain and heat shock protein response to an acute bout of eccentric exercise. The results suggest that downhill exercise training improves mitochondrial calcium homeostasis following an acute bout of prolonged eccentric exercise and may stabilize mitochondrial respiratory function. These improvements coincide with a reduction in calpain activity and heat shock protein upregulation. 相似文献
992.
The influence of early relational experience on later social understanding has evoked rich theoretical discussion but relatively little empirical inquiry. Enlisting data from the NICHD Study of Early Child Care and Youth Development, measures of the security of attachment in infancy, toddlerhood, and early childhood, together with measures of parenting quality (maternal sensitivity and depressive symptoms) gathered longitudinally throughout infancy and early childhood, were used to predict differences in children's thoughts and feelings about peers (i.e., social problem solving, negative attributional biases, aggressive solutions to ambiguous social situations, and self-reported loneliness) when children were 54 months and in first grade. Relational experiences, especially before 36 months, were significantly predictive of later peer-related representations. Attachment security at 24 and 36 months was associated with enhanced social problem-solving skills and less loneliness, but security of attachment at 15 months was nonpredictive. Early maternal sensitivity was positively associated with later social problem-solving and negatively with aggressive responses, and early maternal depressive symptoms were positively associated with children's negative attributions. Concurrent parenting quality was also associated with children's thoughts and feelings about peers, but less consistently. These findings shed new light on how early relational experiences may contribute to social information processing with peers at the end of the preschool years, and that the timing of relational influences may be crucial. 相似文献
993.
Zahra?MA?MohammedEmail author Donald?C?McMillan Joanne?Edwards Elizabeth?Mallon Julie?C?Doughty Clare?Orange James?J?Going 《BMC clinical pathology》2013,13(1):31
Background
Several well-established tumour prognostic factors are used to guide the clinical management of patients with breast cancer. Lymphovascular invasion and angiogenesis have also been reported to have some promise as prognostic factors. The aim of the present study was to examine the prognostic value of tumour lymphovascular invasion and microvessel density compared with that of established prognostic factors in invasive ductal breast cancer.Methods
In addition to hormone receptor status and Ki-67 proliferative activity, lymphovascular invasion and microvessel density and their relationship with survival were examined in patients with invasive ductal breast cancer. Full sections and tissue microarrays (n?=?384 patients) were utilised to assess these factors and were scored by appropriate methods.Results
On univariate analysis tumour size (P?<?0.05), lymph node involvement (P?<?0.01), lymphovascular invasion (P?<?0.05), microvessel density (P?<?0.05) and local- regional treatment (P?<?0.01) were associated with poorer survival in ER negative tumours. On multivariate analysis in ER negative tumours lymph node involvement (P?<?0.01) and local- regional treatment (P?<?0.05) were independently associated with poorer cancer-specific survival. On univariate analysis tumour grade (P?<?0.05), lymph node involvement (P?<?0.001), HER-2 (P?<?0.05), Ki-67 (P?<?0.01) and lymphovascular invasion (P?<?0.001) were associated with poorer survival in ER positive tumours. On multivariate analysis lymph node involvement (P?<?0.001), Ki-67 (P?<?0.001) and lymphovascular invasion (P?<?0.05) were independently associated with poorer cancer-specific survival in ER positive tumours.Conclusion
Lymphovascular invasion but not microvessel density was independently associated with poorer survival in patients with ER positive but not ER negative invasive ductal breast cancer.994.
Background
Informed decision making requires that those individuals making health and health-care decisions understand the advantages and disadvantages associated with particular health options. Research and theory suggest factors that contribute to the decision-making process: data on the likelihood of risks and benefits, level of certainty about outcomes, familiarity with the health issue, characteristics of information sources and presentation, and patient values and beliefs. As the health information environment increases in complexity, it becomes important to understand how interactions among information sources, family, and friends may affect the processing of health information and choices and their alignment with available evidence.Analysis
This paper discusses the potential interactions among social networks, information sources and evidential preferences for health information as they influence health decisions. The role of family and friends who increasingly search for health information for others and the potential for information filtering influenced by second- or third-party attitudes and preferences is explored. Evidential preferences suggestive of the potential value of social math (creatively presented statistics) strategies for presenting data, the information-processing factors that may make personal experiences, anecdotes and testimonials that are often shared within social networks and may exert powerful influences on health decisions are examined in this article.Conclusions
The paper concludes with recommendations for revised health-communication practices, health professional training to improve patient understanding in the clinical encounter, and directions for future research. Simple, direct, and socially relevant communications that avoid conflicts with the values and beliefs of the individual, as well as those of the family and social network, are recommended.995.
Stephanie M. Thornber Lucy M. Mottram Amber R. Mason Paul Thompson Martin C. Stennett Neil C. Hyatt 《RSC advances》2020,10(54):32497
The immobilisation and disposal of fissile materials from civil and defence nuclear programmes requires compatible, passively safe and proliferation resistant wasteforms. In this study, we demonstrate the application of an albite glass–zirconolite ceramic material for immobilisation of chloride contaminated plutonium oxide residues in the United Kingdom. The chlorine solubility limit in the albite glass phase was determined to be 1.0 ± 0.1 wt%, above the maximum envisaged chorine inventory of 0.5 wt%, attainable at a 20 wt% PuO2 incorporation rate within the ceramic. Cl K-edge of X-ray Absorption Near Edge Spectroscopy (XANES) was exploited to confirm partitioning of Cl to the glass phase, speciated as the chloride anion, with exsolution of crystalline NaCl above the chlorine solubility limit. Combinatorial fitting of Cl XANES data, utilising a library of chemically plausible reference spectra, demonstrated the association of Cl with Na and Ca modifier cations, with environments characteristic of the aluminosilicate chloride minerals eudialyte, sodalite, chlorellestadite and afghanite. Adventitious incorporation of Ca, Zr and Ti within the albite glass phase apparently assists chlorine solubility, by templating a local chemical environment characteristic of the mineral reference compounds. The partitioning of Ce, as a Pu analogue, within the glass–ceramic was not adversely impacted by incorporation of Cl. The significance of this research is in demonstrating the compatibility of the glass–ceramic wasteform toward Cl solubility at the expected incorporation rate, below the determined solubility limit. Thus, an upstream heat treatment facility to remove chloride contamination, as specified in the current conceptual flowsheet, would not be required from the perspective of wasteform compatibility, thus providing scope to de-risk the technology roadmap and reduce the projected capital and operational plant costs.Understanding chlorine speciation and incorporation in glass ceramic wasteforms underpins future treatment of contaminated plutonium residues. 相似文献
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Comparative impact of continent and incontinent urinary diversion on long‐term renal function after radical cystectomy in patients with preoperative chronic kidney disease 2 and chronic kidney disease 3a
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