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101.
A cellular transtelephonic defibrillator for management of cardiac arrest outside the hospital 总被引:1,自引:0,他引:1
G W Dalzell P P McKeown M J Roberts A A Adgey 《The American journal of cardiology》1991,68(9):909-912
A cellular transtelephonic defibrillator facilitates early defibrillation in remote areas and involves electrocardiographic diagnosis and defibrillation control by a physician remote from but in voice contact with the patient-unit operator. The patient unit contains a microprocessor, microphone, defibrillator, electrocardiogram/defibrillator electrode pads and cellular telephone. Activation of the patient-unit initiates automatic dialing and contact with the remotely sited base station within 35 to 50 seconds. The physician at the base station identifies the rhythm and controls defibrillator charging and discharge. The minimal interaction required between the system and the local operator makes it suitable for use by minimally trained first responders. The cellular transtelephonic defibrillator has been tested in 211 calls responded to by a physician-manned mobile coronary care unit over distances up to 15 miles in an urban area. Satisfactory electrocardiographic transmission and voice communication were established in 172 of 211 calls (81.5%). In 39 (18.5%), connection with the base station either could not be established or maintained mainly because of geographic location or battery failure. One hundred direct current shocks of 50 to 360 J were effectively administered to 22 patients with 48 episodes of ventricular fibrillation or ventricular tachycardia with successful correction of 46 of 48 episodes using 1 to 4 shocks per episode. Widespread distribution of such devices could improve survival in patients with cardiac arrest outside the hospital. 相似文献
102.
Jennifer S. Gewandter Michael P. McDermott Andrew McKeown Shannon M. Smith Mark R. Williams Matthew Hunsinger John Farrar Dennis C. Turk Robert H. Dworkin 《Pain》2014
Missing data in clinical trials can bias estimates of treatment effects. Statisticians and government agencies recommend making every effort to minimize missing data. Although statistical methods are available to accommodate missing data, their validity depends on often untestable assumptions about why the data are missing. The objective of this study was to assess the frequency with which randomized clinical trials published in 3 major pain journals (ie, European Journal of Pain, Journal of Pain, and Pain) reported strategies to prevent missing data, the number of participants who completed the study (ie, completers), and statistical methods to accommodate missing data. A total of 161 randomized clinical trials investigating treatments for pain, published between 2006 and 2012, were included. Approximately two-thirds of the trials reported at least 1 method that could potentially minimize missing data, the most common being allowance of concomitant medications. Only 61% of the articles explicitly reported the number of patients who were randomized and completed the trial. Although only 14 articles reported that all randomized participants completed the study, fewer than 50% of the articles reported a statistical method to accommodate missing data. Last observation carried forward imputation was used most commonly (42%). Thirteen articles reported more than 1 method to accommodate missing data; however, the majority of methods, including last observation carried forward, were not methods currently recommended by statisticians. Authors, reviewers, and editors should prioritize proper reporting of missing data and appropriate use of methods to accommodate them so as to improve the deficiencies identified in this systematic review. 相似文献
103.
Jennifer S. Gewandter Shannon M. Smith Andrew McKeown Laurie B. Burke Sharon H. Hertz Matthew Hunsinger Nathaniel P. Katz Allison H. Lin Michael P. McDermott Bob A. Rappaport Mark R. Williams Dennis C. Turk Robert H. Dworkin 《Pain》2014
Performing multiple analyses in clinical trials can inflate the probability of a type I error, or the chance of falsely concluding a significant effect of the treatment. Strategies to minimize type I error probability include prespecification of primary analyses and statistical adjustment for multiple comparisons, when applicable. The objective of this study was to assess the quality of primary analysis reporting and frequency of multiplicity adjustment in 3 major pain journals (ie, European Journal of Pain, Journal of Pain, and PAIN®). A total of 161 randomized controlled trials investigating noninvasive pharmacological treatments or interventional treatments for pain, published between 2006 and 2012, were included. Only 52% of trials identified a primary analysis, and only 10% of trials reported prespecification of that analysis. Among the 33 articles that identified a primary analysis with multiple testing, 15 (45%) adjusted for multiplicity; of those 15, only 2 (13%) reported prespecification of the adjustment methodology. Trials in clinical pain conditions and industry-sponsored trials identified a primary analysis more often than trials in experimental pain models and non-industry-sponsored trials, respectively. The results of this systematic review demonstrate deficiencies in the reporting and possibly the execution of primary analyses in published analgesic trials. These deficiencies can be rectified by changes in, or better enforcement of, journal policies pertaining to requirements for the reporting of analyses of clinical trial data. 相似文献
104.
105.
Edson de Sousa Barros Júnior Mara Eliane Soares Ribeiro Rafael Rodrigues Lima Mrio Honorato da Silva e Souza Júnior Sandro Cordeiro Loretto 《Materials》2022,15(21)
This study aimed to evaluate the effects of 22% carbamide peroxide combined with an erosive challenge and simulated brushing on enamel. Bovine incisor teeth were divided into G1, tooth bleaching; G2, tooth bleaching + erosive challenge; and G3, tooth bleaching + erosive challenge + simulated brushing, and evaluated at T0, before any intervention; T1, 14 days after the proposed treatments; and T2, 28 days after the proposed treatments. Tooth bleaching was performed daily for 1 h for 28 days. The microhardness, surface roughness, mass variation, and ultrastructure were analyzed at T0, T1, and T2. Two-way analysis of variance for repeated measures was performed and Tukey’s post hoc test (α = 5%) was used. The surface roughness increased in groups G2 and G3 as a function of time, whereas microhardness and mass measurements demonstrated a significant reduction for groups associated with challenges. Ultrastructural evaluation indicated a loss of the aprismatic layer and exposure of the enamel prisms in all groups after 14 days of bleaching, with more pronounced results in G2 and G3 after 28 days. In conclusion, abrasive and erosive challenges potentiated the deleterious effects of tooth whitening on microhardness, ultramorphology, and mass, without affecting the roughness of dental enamel. 相似文献
106.
Sociologists of childhood have stressed the importance of children??s experience in the present and children as agents who actively construct their own lives and influence relationships with family and friends. Current thinking in the field of child well-being emphasises the need to consult children as experts in their own lives. Findings from research with children have led to important insights about what contributes to well-being. Relationships with family and friends have been found to be central to well-being whilst bullying by peers deeply impacts on their well-being. Shared activities appear to be the context for children to not only master competences but also learn about and negotiate relationships. The Growing Up in Ireland interviews with 9?year old children were re-analysed with a view to exploring these crucial domains and how they impact on the children??s well-being. The children were found to have a wide circle of family connections and were particularly close to their mothers although also close to their fathers. Grandparents played a significant role in their lives and their relationships with siblings were often positive but did fluctuate. Reasons for closeness centred around trust. Lack of availability due to work was a key contributor to children feeling less close to a family member. The children were involved in a wide range of structured activities after school and at the weekend, This was usually balanced with free time although some ??hurried?? children had frenetic lifestyles. Involvement in unstructured activities such as free play was particularly associated with time with friends and choice. Friendship was characterised by sharing and trust. On the other hand, bullying by peers had been experienced by many of the children and almost all were conscious of the danger of becoming bullied. The wider issues of work-family balance and its impact on children, the predominance of bullying and children??s right to be heard are reflected upon. 相似文献
107.
A C Fiore T D Ivey P P McKeown G A Misbach M D Allen D H Dillard 《The Annals of thoracic surgery》1986,42(4):372-379
Twenty-three patients with bacterial endocarditis and mycotic aneurysms of the aortic annulus were treated between 1978 and 1985. There were 18 men and 5 women ranging from 24 to 72 years old. All patients had congestive heart failure and positive blood cultures as a complication of the endocarditis and were in New York Heart Association (NYHA) Functional Class III or IV. The aneurysm complicated late prosthetic valve endocarditis in 7 patients and native valve endocarditis in 16. The most common infecting organisms were streptococci (12 patients) and staphylococci (7 patients). The noncoronary sinus was the most frequent site for aneurysm formation. Following debridement of the abscess cavity, the orifice of the aneurysm was closed with a patch of Dacron in 20 patients and autologous pericardium in 3. A prosthetic valve (18 bioprosthetic and 5 mechanical) was secured to the noninfected portion of the native annulus and to the patch at the level of annulus. There were 3 deaths, 1 perioperative and 2 late, each without evidence of residual infection or aortic insufficiency. There are 20 late survivors (87%). After a mean follow-up of 1 year, all patients are in NYHA Functional Class I. Patch closure of mycotic aneurysms involving the aortic annulus permits aggressive debridement of the abscess cavity and affords closure of the orifice without tension. The prosthetic valve can be seated at the level of the native annulus, thus avoiding complicated reconstructive procedures of the aortic root and coronary arteries. This technique is an effective alternative in selected cases of mycotic aneurysms involving the aortic annulus. 相似文献
108.
109.
Members of the ALP/Enigma family of PDZ-LIM proteins play a role in cytoskeletal anchorage and mutations in at least one member of this family are associated with human cardiomyopathy. Here, we describe the analysis of the Caenorhabditis elegans alp-1 gene. alp-1 is predicted to encode the entire nematode ALP/Enigma protein family, consisting of one ALP-related protein with a single LIM domain and three Enigma-like proteins containing four LIM domains. We demonstrate that the ALP-1 proteins are expressed in muscle cells, where they localize to actin anchorage and muscle attachment sites. We show that the PDZ domain of the ALP-1 proteins is sufficient to target the protein to the dense bodies, which are important actin anchorage sites in C. elegans body wall muscle. We demonstrate that the C. elegans ALP/Enigma proteins are also localized to cell-cell junctions and to both epithelial and muscle cell nuclei. These findings suggest new roles for the ALP/Enigma protein family that may lead to the understanding of their involvement in cardiomyopathy. 相似文献
110.