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排序方式: 共有721条查询结果,搜索用时 34 毫秒
711.
Kapetanakis EI Athanasiou T Mestres CA Nashef SA Aagaard J Moritz A Van Ingen G Chronidou F Palatianos G Alivizatos PA Stavridis GT 《The Journal of heart valve disease》2008,17(2):200-205
BACKGROUND AND AIMS OF THE STUDY: Prompted by anecdotal evidence and observations by surgeons, an investigation was undertaken into the potential differences in implanted aortic valve prosthesis sizes, during aortic valve replacement (AVR) procedures, between northern and southern European countries. METHODS: A multi-institutional, non-randomized, retrospective analysis was conducted among 2,932 patients who underwent AVR surgery at seven tertiary cardiac surgery centers throughout Europe. Demographic and perioperative variables including valve size and type, body surface area (BSA) and early mortality were collected. Group analysis by patient geographic distribution and by annular diameter of the prosthesis utilized was conducted. Patients with a manufacturer's labeled prosthesis size > or = 21 mm were assigned to the 'large' aortic size subset, while those with a prosthesis size < 21 mm were assigned to the 'small' aortic size subset. Effective orifice area indices were calculated for all patients to assess the geographic distribution of patient-prosthesis mismatch. Univariable and multivariable logistic regression analyses adjusting for possible confounding variables were performed. RESULTS: Prostheses with diameter < 21 mm were implanted at almost twice the rate in southern Europe compared to the north (56.4% versus 26.7%, p < 0.01). The mean valve size was also smaller in southern compared to northern European patients (21.6 +/- 2.1 mm versus 23.4 +/- 2.2 mm, p < 0.01). There were no regional differences in the distribution of either gender or BSA. In the multivariable model, south European patients were seven times more likely to receive a smaller-sized aortic valve (OR = 6.5, 95% CI = 4.82-8.83, p < 0.01), and thus the odds of developing patient-prosthesis mismatch were increased two-fold in southern European patients (OR = 1.9, 95% CI = 1.25-2.80, p = 0.02). However, neither geographic distribution nor valve size were significantly associated with operative mortality. CONCLUSION: The study results demonstrated differences in implanted aortic valve size, between the participating northern and southern European countries. Imbalances in the prevalence of rheumatic heart disease, health resource availability and variations in surgical practice throughout Europe might be possible etiological causes. 相似文献
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Identification of an additional negative regulatory region for p53 sequence-specific DNA binding 总被引:3,自引:0,他引:3 下载免费PDF全文
Beate F. Müller-Tiemann Thanos D. Halazonetis James J. Elting 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(11):6079-6084
The DNA binding activity of p53 is crucial for its tumor suppressor function and is subject to tight regulation. Previous studies revealed that the inhibitory function of the p53 C terminus is implicated in the latent, low affinity sequence-specific DNA binding activity of p53 in the uninduced state. Sequence-specific DNA binding of p53 has been shown to be activated by several posttranslational modifications and interacting proteins that target predominantly the C terminus. Moreover, several authors have shown that synthetic peptides corresponding to p53 C-terminal sequences activate p53 sequence-specific DNA binding. In an effort to identify the interaction site of p53 with these activating peptides we assessed complex formation between p53 deletion constructs and C-terminal activating peptides by peptide affinity precipitation. This study revealed that two distal regions of the p53 molecule contribute synergistically to the interaction with activating C-terminal peptides: amino acids 80–93 and 364–393. The C-terminal residues 364–393 are already well characterized as having negative regulatory function. DNA binding analyses with these deletion constructs reveal a comparable negative regulatory activity for residues 80–93, defining this region as a previously unidentified negative regulatory domain of p53. Furthermore, synthetic peptides spanning this newly identified proline-rich negative regulatory region (residues 80–93) are able to activate p53 sequence-specific DNA binding in vitro. We suggest that both negative regulatory regions, residues 80–93 and 364–393, contribute cooperatively to the maintenance of the latent, low-affinity DNA binding conformation of p53. 相似文献
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L Harling T Athanasiou H Ashrafian J Kokotsakis V Brown A Nathan R Casula 《Journal of cardiothoracic surgery》2012,7(1):80
ABSTRACT: Papillary fibroelastomas are rare primary tumours of cardiac origin accounting for approximately 10% of all primary cardiac neoplasms. Due to a high thromboembolic risk, surgical excision is the mainstay of treatment these patients and median sternotomy the most widely used approach. We describe the case of a 43 year-old lady presenting with acute myocardial infarction secondary to aortic valve papillary fibroelastoma subsequently excised using a minimal access technique. From our experience mini-sternotomy offers excellent exposure and allows for safe resection in such cases, improving cosmesis without compromising either intra or post-operative outcome. 相似文献
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A hallmark of brain organization is the integration of primary and modulatory pathways by principal neurons. Primary sensory inputs are usually not plastic, while modulatory inputs converging to the same principal neuron can be plastic. However, the mechanisms determining this input-specific expression of synaptic plasticity remain unknown. We investigated this problem in the dorsal cochlear nucleus (DCN), where principal cells integrate primary auditory nerve input with plastic, parallel fiber input. Our previous DCN studies have shown that parallel fiber inputs exhibit short- and long-term plasticities mediated by endocannabinoid signaling. Here we show that auditory nerve inputs to principal cells do not show short- or long-term endocannabinoid-mediated synaptic plasticity. Electrophysiological and electron microscopy studies indicate that input specificity arises from selective expression of presynaptic cannabinoid (CB1) receptors in parallel fiber terminals, but not in auditory nerve terminals. However, pairing of parallel fiber activity with auditory nerve activity elicits plasticity in parallel fiber inputs, thus suggesting a role for synaptic plasticity in multisensory integration. 相似文献
719.
This systematic review describes tools which could be considered for use for holistic needs assessment (HNA) in brain cancer. MEDLINE, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and PsycINFO were searched. Studies were included which met the following criteria; primary research published in English which reported the development, psychometric testing or clinical utility testing of patient‐reported outcome measures (PROMs) for the assessment of adult brain cancer patients’ needs, problems or concerns or generic cancer needs assessment tools developed specifically on a brain cancer or brain tumour population. Nine articles describing four tools were identified. The tools were first assessed using the COSMIN protocol for systematic reviews of measurement properties and then assessed for their quality and usefulness as a holistic needs assessment tool. None of the four tools had strong psychometric properties; however, the two symptom questionnaires had better psychometric properties but would need adapted to holistically assess the multiple domains of need. The two HNA tools had only minimal psychometric testing. The lack of a tool, which adequately meets all requirements for HNA, supports the need to further development of tools to optimise this intervention. 相似文献
720.