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91.
92.
Kyung Hwa Lee Greg J. Siegle Ronald E. Dahl Jill M. Hooley Jennifer S. Silk 《Social cognitive and affective neuroscience》2015,10(7):902-912
Parental criticism can have positive and negative effects on children’s and adolescents’ behavior; yet, it is unclear how youth react to, understand and process parental criticism. We proposed that youth would engage three sets of neural processes in response to parental criticism including the following: (i) activating emotional reactions, (ii) regulating those reactions and (iii) social cognitive processing (e.g. understanding the parent’s mental state). To examine neural processes associated with both emotional and social processing of parental criticism in personally relevant and ecologically valid social contexts, typically developing youth were scanned while they listened to their mother providing critical, praising and neutral statements. In response to maternal criticism, youth showed increased brain activity in affective networks (e.g. subcortical–limbic regions including lentiform nucleus and posterior insula), but decreased activity in cognitive control networks (e.g. dorsolateral prefrontal cortex and caudal anterior cingulate cortex) and social cognitive networks (e.g. temporoparietal junction and posterior cingulate cortex/precuneus). These results suggest that youth may respond to maternal criticism with increased emotional reactivity but decreased cognitive control and social cognitive processing. A better understanding of children’s responses to parental criticism may provide insights into the ways that parental feedback can be modified to be more helpful to behavior and development in youth. 相似文献
93.
Comparative impacts of two major hurricane seasons on the Neuse River and western Pamlico Sound ecosystems 总被引:1,自引:0,他引:1 下载免费PDF全文
Burkholder J Eggleston D Glasgow H Brownie C Reed R Janowitz G Posey M Melia G Kinder C Corbett R Toms D Alphin T Deamer N Springer J 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(25):9291-9296
Ecosystem-level impacts of two hurricane seasons were compared several years after the storms in the largest lagoonal estuary in the U.S., the Albemarle-Pamlico Estuarine System. A segmented linear regression flow model was developed to compare mass-water transport and nutrient loadings to a major artery, the Neuse River Estuary (NRE), and to estimate mean annual versus storm-related volume delivery to the NRE and Pamlico Sound. Significantly less water volume was delivered by Hurricane Fran (1996), but massive fish kills occurred in association with severe dissolved oxygen deficits and high contaminant loadings (total nitrogen, total phosphorus, suspended solids, and fecal bacteria). The high water volume of the second hurricane season (Hurricanes Dennis, Floyd, and Irene in 1999) delivered generally comparable but more dilute contaminant loads, and no major fish kills were reported. There were no discernable long-term adverse impacts on water quality. Populations of undesirable organisms, such as toxic dinoflagellates, were displaced down-estuary to habitats less conducive for growth. The response of fisheries was species-dependent: there was no apparent impact of the hurricanes on commercial landings of bivalve molluscs or shrimp. In contrast, interacting effects of hurricane floodwaters in 1999 and intensive fishing pressure led to striking reductions in blue crabs. Overall, the data support the premise that, in shallow estuaries frequently disturbed by hurricanes, there can be relatively rapid recovery in water quality and biota, and benefit from the scouring activity of these storms. 相似文献
94.
de Bono S Riechmann L Girard E Williams RL Winter G 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(5):1396-1401
It has been suggested that protein domains evolved by the non-homologous recombination of building blocks of subdomain size. In earlier work we attempted to recapitulate domain evolution in vitro. We took a polypeptide segment comprising three beta-strands in the monomeric, five-stranded beta-barrel cold shock protein (CspA) of Escherichia coli as a building block. This segment corresponds to a complete exon in homologous eukaryotic proteins and includes residues that nucleate folding in CspA. We recombined this segment at random with fragments of natural proteins and succeeded in generating a range of folded chimaeric proteins. We now present the crystal structure of one such combinatorial protein, 1b11, a 103-residue polypeptide that includes segments from CspA and the S1 domain of the 30S ribosomal subunit of E. coli. The structure reveals a segment-swapped, six-stranded beta-barrel of unique architecture that assembles to a tetramer. Surprisingly, the CspA segment retains its structural identity in 1b11, recapitulating its original fold and deforming the structure of the S1 segment as necessary to complete a barrel. Our work provides structural evidence that (i) random shuffling of nonhomologous polypeptide segments can lead to folded proteins and unique architectures, (ii) many structural features of the segments are retained, and (iii) some segments can act as templates around which the rest of the protein folds. 相似文献
95.
Protein tyrosine phosphatase PTP1B suppresses p210 bcr-abl-induced transformation of Rat-1 fibroblasts and promotes differentiation of K562 cells 总被引:6,自引:1,他引:6 下载免费PDF全文
Kenneth R. LaMontagne Jr. Greg Hannon Nicholas K. Tonks 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(24):14094-14099
The bcr-abl chimeric oncoprotein exhibits deregulated protein tyrosine kinase activity and is implicated in the pathogenesis of Philadelphia chromosome (Ph)-positive human leukemias, such as chronic myelogenous leukemia (CML). Recently we have shown that the levels of the protein tyrosine phosphatase PTP1B are enhanced in p210 bcr-abl-expressing cell lines. Furthermore, PTP1B recognizes p210 bcr-abl as a substrate, disrupts the formation of a p210 bcr-abl/Grb2 complex, and inhibits signaling events initiated by this oncoprotein PTK. In this report, we have examined whether PTP1B effects transformation induced by p210 bcr-abl. We demonstrate that expression of either wild-type PTP1B or the substrate-trapping mutant form of the enzyme (PTP1B-D181A) in p210 bcr-abl-transformed Rat-1 fibroblasts diminished the ability of these cells to form colonies in soft agar, to grow in reduced serum, and to form tumors in nude mice. In contrast, TCPTP, the closest relative of PTP1B, did not effect p210 bcr-abl-induced transformation. Furthermore, neither PTP1B nor TCPTP inhibited transformation induced by v-Abl. In addition, overexpression of PTP1B or treatment with CGP57148, a small molecule inhibitor of p210 bcr-abl, induced erythroid differentiation of K562 cells, a CML cell line derived from a patient in blast crisis. These data suggest that PTP1B is a selective, endogenous inhibitor of p210 bcr-abl and is likely to be important in the pathogenesis of CML. 相似文献
96.
A safety study on intrathecal delivery of autologous mesenchymal stromal cells in rabbits directly supporting Phase I human trials 下载免费PDF全文
97.
Minimal access reoperative mitral and aortic valve surgery 总被引:1,自引:0,他引:1
Grossi EA LaPietra A Bizekis C Ribakove G Galloway AC Colvin SB 《Current cardiology reports》2000,2(6):572-574
Minimally invasive cardiac surgery has allowed surgeons to perform valve procedures with a morbidity and mortality comparable
with conventional resternotomy approaches while reducing postoperative ventilatory and intensive care unit requirements and
overall hospital length of stay. Additionally, patient satisfaction with rapid recovery, earlier return to work, and improved
cosmetic results has pushed the pendulum of reoperative valve surgery towards minimally invasive techniques. We reviewed our
institutional data consisting of 129 patients requiring reoperative valve surgery over the past 4 years, which was accomplished
using these minimally invasive approaches. 相似文献
98.
Background
The Health Information Technology for Economic and Clinical Health (HITECH) Act imposes pressure on health care organizations to qualify for “Meaningful Use”. It is assumed that portals should increase patient participation in medical decisions, but whether or not the use of portals improves outcomes remains to be seen.Objective
The purpose of this systemic review is to outline and summarize study results on the effect of patient portals on quality, or chronic-condition outcomes as defined by the Agency for Healthcare Research and Quality, and its implications to Meaningful Use since the beginning of 2011. This review updates and builds on the work by Ammenwerth, Schnell-Inderst, and Hoerbst.Methods
We performed a systematic literature search in PubMed, CINAHL, and Google Scholar. We identified any data-driven study, quantitative or qualitative, that examined a relationship between patient portals, or patient portal features, and outcomes. We also wanted to relate the findings back to Meaningful Use criteria. Over 4000 articles were screened, and 27 were analyzed and summarized for this systematic review.Results
We identified 26 studies and 1 review, and we summarized their findings and applicability to our research question. Very few studies associated use of the patient portal, or its features, to improved outcomes; 37% (10/27) of papers reported improvements in medication adherence, disease awareness, self-management of disease, a decrease of office visits, an increase in preventative medicine, and an increase in extended office visits, at the patient’s request for additional information. The results also show an increase in quality in terms of patient satisfaction and customer retention, but there are weak results on medical outcomes.Conclusions
The results of this review demonstrate that more health care organizations today offer features of a patient portal than in the review published in 2011. Articles reviewed rarely analyzed a full patient portal but instead analyzed features of a portal such as secure messaging, as well as disease management and monitoring. The ability of patients to be able to view their health information electronically meets the intent of Meaningful Use, Stage 2 requirements, but the ability to transmit to a third party was not found in the review. 相似文献99.
Brent Doney Eva Hnizdo Monica Graziani Greg Kullman Cecil Burchfiel Sherry Baron 《COPD》2014,11(4):368-380
Introduction: The contribution of occupational exposure to the risk of chronic obstructive pulmonary disease COPD in population-based studies is of interest. We compared the performance of self-reported exposure to a newly developed JEM in exposure-response evaluation. Methods: We used cross-sectional data from Multi-Ethnic Study of Atherosclerosis (MESA), a population-based sample of 45–84 year olds free of clinical cardiovascular disease at baseline. MESA ascertained the most recent job and employment, and the MESA Lung Study measured spirometry, and occupational exposures for 3686 participants. Associations between health outcomes (spirometry defined airflow limitation and Medical Research Council-defined chronic bronchitis) and occupational exposure [self-reported occupational exposure to vapor-gas, dust, or fumes (VGDF), severity of exposure, and a job-exposure matrix (JEM)-derived score] were evaluated using logistic regression models adjusted for non-occupational risk factors. Results: The prevalence of airflow limitation was associated with self-reported exposure to vapor-gas (OR 2.6, 95%CI 1.1–2.3), severity of VGDF exposure (P-trend < 0.01), and JEM dust exposure (OR 2.4, 95%CI 1.1–5.0), and with organic dust exposure in females; these associations were generally of greater magnitude among never smokers. The prevalence of chronic bronchitis and wheeze was associated with exposure to VGDF. The association between airflow limitation and the combined effect of smoking and VGDF exposure showed an increasing trend. Self-reported vapor-gas, dust, fumes, years and severity of exposure were associated with increased prevalence of chronic bronchitis and wheeze (P < 0.001). Conclusions: Airflow limitation was associated with self-reported VGDF exposure, its severity, and JEM-ascertained dust exposure in smokers and never-smokers in this multiethnic study. 相似文献
100.
Error processing is frequently examined using the error‐related negativity (ERN), a negative‐going event‐related potential occurring after the commission of an error at frontal‐central sites, and has been suggested as a neural biomarker that may be useful in characterizing trajectories of risk for anxiety. While the ERN has been shown to have excellent psychometric properties in adults, few studies have examined psychometric properties of the ERN in children and adolescents. The current study examined the 2‐year test‐retest reliability of the ERN in a sample of children and adolescents, and the convergent validity of the ERN using a flanker and go/no‐go task. Results suggest that the ERN is both reliable and stable across 2 years and across tasks. However, results also indicate that the internal consistency obtained using the flanker task is greater than the internal consistency obtained using the go/no‐go task. 相似文献