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排序方式: 共有8311条查询结果,搜索用时 15 毫秒
21.
D T Zero R F Raubertas A M Pedersen J Fu A L Hayes J D Featherstone 《Journal of dental research》1992,71(9):1546-1552
Previous studies have focused on enamel and plaque as the primary sites of fluoride (F) retention in the mouth. The present study was undertaken to evaluate the role of oral soft tissue as a site of F retention by comparing an edentulous subject panel (n = 9) with a fully dentate panel (n = 10). Unstimulated whole saliva samples were collected by having subjects pool saliva for two min. Samples were collected over a 24-hour period after application of a placebo dentifrice (PD; 0.4 ppm F), fluoride dentifrice (FD; 1100 ppm F), fluoride rinse (FR; 226 ppm F), or fluoride gel (FG; 5000 ppm F) delivered in custom trays. There was no statistically significant difference in salivary flow rate between the two panels for any of the treatments. The edentulous panel had higher salivary F levels than the dentate panel, which reached statistical significance (p less than 0.05) for the FD and FG treatments. In a separate study involving the same treatments, F levels at specific soft-tissue sites were measured over a one-hour period by use of absorbent discs placed in different soft-tissue areas of the mouth. The tongue and lower posterior vestibule retained the highest F levels, followed by the upper posterior buccal vestibule and upper anterior labial vestibule, with the lowest F levels retained in the lower anterior vestibule and the floor of the mouth. There was a strong-to-moderate correlation between whole saliva F concentration and F levels at specific soft-tissue sites. This study establishes the importance of oral soft tissue as the major site of F retention in the mouth. 相似文献
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Gabrielle Todd Miranda Haberfield Patrick L. Faulkner Caroline Rae Michael Hayes Robert A. Wilcox Janet L. Taylor Simon C. Gandevia Jana Godau Daniela Berg Olivier Piguet Kay L. Double 《Journal of neural transmission (Vienna, Austria : 1996)》2014,121(11):1377-1386
Abnormal substantia nigra morphology in healthy individuals, viewed with transcranial ultrasound, is a significant risk factor for Parkinson’s disease. However, little is known about the functional consequences of this abnormality (termed ‘hyperechogenicity’) on movement. The aim of the current study was to investigate hand function in healthy older adults with (SN+) and without (SN?) substantia nigra hyperechogenicity during object manipulation. We hypothesised that SN+ subjects would exhibit increased grip force and a slower rate of force application compared to SN? subjects. Twenty-six healthy older adults (8 SN+ aged 58 ± 8 years, 18 SN? aged 57 ± 6 years) were asked to grip and lift a light-weight object with the dominant hand. Horizontal grip force, vertical lift force, acceleration, and first dorsal interosseus EMG were recorded during three trials. During the first trial, SN+ subjects exhibited a longer period between grip onset and lift onset (i.e. preload duration; 0.27 ± 0.25 s) than SN? subjects (0.13 ± 0.08 s; P = 0.046). They also exerted a greater downward force prior to lift off (?0.54 ± 0.42 N vs. ?0.21 ± 0.12 N; P = 0.005) and used a greater grip force to lift the object (19.5 ± 7.0 N vs. 14.0 ± 4.3 N; P = 0.022) than SN? subjects. No between group differences were observed in subsequent trials. SN+ subjects exhibit impaired planning for manipulation of new objects. SN+ individuals over-estimate the grip force required, despite a longer contact period prior to lifting the object. The pattern of impairment observed in SN+ subjects shares similarities with de novo Parkinson’s disease patients. 相似文献
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Elizabeth Mann-Salinas Elizabeth Hayes Johnnie Robbins Jean Sabido Laura Feider David Allen Linda Yoder 《Burns : journal of the International Society for Burn Injuries》2014
Aim
To provide a systematic review of the literature regarding development of an evidence-based Precepting Program for nurses transitioning to burn specialty practice.Background
Burned patients are admitted to specialty Burn Centers where highly complex nursing care is provided. Successful orientation and integration into such a specialized work environment is a fundamental component of a nurse's ability to provide safe and holistic patient care.Design
A systematic review of the literature was performed for the period 1995–2011 using electronic databases within PUBMED and Ovid search engines.Data sources
Databases included Medline, CINHAL, ProQuest for Dissertations and Thesis, and Cochran Collaboration using key search terms: preceptor, preceptee, preceptorship, precept*, nurs*, critical care, personality types, competency-based education, and learning styles.Review methods
Nurses graded the level and quality of evidence of the included articles using a modified 7-level rating system and the Johns Hopkins Nursing Quality of Evidence Appraisal during journal-club meetings.Results
A total of 43 articles related to competency (n = 8), knowledge acquisition and personality characteristics (n = 8), learning style (n = 5), preceptor development (n = 7), and Precepting Programs (n = 14).Conclusions
A significant clinical gap existed between the scientific evidence and actual precepting practice of experienced nurses at the Burn Center. Based on this extensive review of the literature, it was determined that a sufficient evidence base existed for development of an evidence-based Precepting Program. 相似文献27.
Aaron L. Fidler Roberto M. Vanacore Sergei V. Chetyrkin Vadim K. Pedchenko Gautam Bhave Viravuth P. Yin Cody L. Stothers Kristie Lindsey Rose W. Hayes McDonald Travis A. Clark Dorin-Bogdan Borza Robert E. Steele Michael T. Ivy The Aspirnauts Julie K. Hudson Billy G. Hudson 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(1):331-336
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Masud H. Khandaker Raul E. Espinosa Rick A. Nishimura Lawrence J. Sinak Sharonne N. Hayes Rowlens M. Melduni Jae K. Oh 《Mayo Clinic proceedings. Mayo Clinic》2010,85(6):572-593
Pericardial diseases can present clinically as acute pericarditis, pericardial effusion, cardiac tamponade, and constrictive pericarditis. Patients can subsequently develop chronic or recurrent pericarditis. Structural abnormalities including congenitally absent pericardium and pericardial cysts are usually asymptomatic and are uncommon. Clinicians are often faced with several diagnostic and management questions relating to the various pericardial syndromes: What are the diagnostic criteria for the vast array of pericardial diseases? Which diagnostic tools should be used? Who requires hospitalization and who can be treated as an outpatient? Which medical management strategies have the best evidence base? When should corticosteroids be used? When should surgical pericardiectomy be considered? To identify relevant literature, we searched PubMed and MEDLINE using the keywords diagnosis, treatment, management, acute pericarditis, relapsing or recurrent pericarditis, pericardial effusion, cardiac tamponade, constrictive pericarditis, and restrictive cardiomyopathy. Studies were selected on the basis of clinical relevance and the impact on clinical practice. This review represents the currently available evidence and the experiences from the pericardial clinic at our institution to help guide the clinician in answering difficult diagnostic and management questions on pericardial diseases.CMR = cardiac magnetic resonance imaging; CT = computed tomography; CYP = cytochrome P450; ECG = electrocardiographic; ESC = European Society of Cardiology; IVC = inferior vena cava; LV = left ventricular; NSAID = nonsteroidal anti-inflammatory drug; RA = right atrium; RV = right ventricleThe pericardium is a thin covering that separates the heart from the remaining mediastinal structures and provides structural support while also having a substantial hemodynamic impact on the heart. The pericardium is not essential—normal cardiac function can be maintained in its absence—however, diseased pericardium presenting clinically as acute or chronic recurrent pericarditis, pericardial effusion, cardiac tamponade, and pericardial constriction can be challenging to manage and life-threatening in some cases. The etiology of pericardial disease is often difficult to determine or remains idiopathic. However, microorganisms, including viruses and bacteria; systemic illnesses, including neoplasia, autoimmune disease, and connective tissue disease; renal failure; previous cardiac surgery; previous myocardial infarction; trauma; aortic dissection; radiation; and, rarely, drugs have been associated with pericardial diseases.The diagnosis and management of pericardial diseases remain challenging because of the vast spectrum of manifestations and the lack of clinical data on which to base guidelines by the American College of Cardiology and the American Heart Association. However, the European Society of Cardiology (ESC) published guidelines on pericardial disease in 2004.1 This review aims to describe the methods of diagnosing and managing major pericardial syndromes on the basis of the literature and the clinical experience of our pericardial clinic. Searches were performed on PubMed and MEDLINE using the keywords diagnosis, treatment, management, acute pericarditis, relapsing or recurrent pericarditis, pericardial effusion, cardiac tamponade, constrictive pericarditis, and restrictive cardiomyopathy. No date limitations were set. Studies were selected on the basis of clinical relevance and the impact on clinical practice. 相似文献
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Donna L. Berry Fangxin Hong Traci M. Blonquist Barbara Halpenny Christopher P. Filson Viraj A. Master Martin G. Sanda Peter Chang Gary W. Chien Randy A. Jones Tracey L. Krupski Seth Wolpin Leslie Wilson Julia H. Hayes Quoc-Dien Trinh Mitchell Sokoloff Prabhakara Somayaji 《The Journal of urology》2018,199(1):89-97