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121.
How to perform a comprehensive search for FDG-PET literature   总被引:1,自引:0,他引:1  
In this study, a comprehensive, unbiassed search strategy for identifying literature on fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) in Medline, Embase and Current Contents was developed, with specific search strategies for each database, using MeSH terms as well as free text words for PET and FDG. To examine which text words apply to FDG, we evaluated the ways of spelling FDG in a random sample of FDG-PET articles (n=100). These words were used as free text words in the two databases and overlap was determined. PET publications were identified using the text words ”positron emission tomography” and ”pet$” combined with the respective MeSH terms for each database. To compare the yield of the combined FDG-PET strategy in each database, the retrieved citations were downloaded to Pro-Cite 4.0. Finally, we added search terms for lung cancer, breast cancer, melanoma, head and neck cancer and lymphoma to our strategy and to a short strategy (consisting of the text words ”positron emission tomography” and ”fdg”). In order to measure the yield and precision (positive predictive value, PPV) of our search strategy and compare it with the short one, we screened the title and abstract of the retrieved citations. Reviewing a random sample of the FDG-PET literature yielded 56 different ways of spelling FDG. We confined the list to 11 text words, without missing articles. Of the publications retrieved by these text words, only 4% were indexed by the MeSH term ”Fludeoxyglucose F18” in Medline and 29% by the MeSH-term ”Fluorodeoxyglucose F18” in Embase. Only 51% of PET articles were indexed by the MeSH term ”Tomography, emission-computed” in Medline and 40% by the MeSH term ”Positron emission tomography” in Embase. The combined search strategy for identifying studies on FDG and PET resulted in 2865 publications in Medline and 2646 in Embase. Medline identified 1662 publications not found by Embase; Embase identified 1422 publications not found by Medline. Compared with the short strategy, our search strategy yielded on average 52% more publications (94%, 41% and 20% more in Medline, Embase and Current Contents, respectively). The PPV of our strategy (percent of publications that were really on PET, FDG and the specified subject) was 70%, compared with 76% using the short strategy. Regardless of the strategy used, Embase yielded more publications and was also slightly more specific than Medline. With the recommended strategy, FDG-PET publications can be identified more efficiently. We have shown the importance of searching more than one database and emphasize the use of both MeSH terms and text words in a search strategy. Standardization of the spelling of FDG and indexing of articles on FDG would substantially simplify searching. Received 5 July and in revised form 25 September 1999  相似文献   
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Seventy-seven very low birthweight (VLBW) infants (mean birthweight 891 +/- 209 g) with a diagnosis of bronchopulmonary dysplasia (BPD) were treated with a steroid (dexamethasone) in an attempt to wean them from mechanical ventilation. Seventeen of 77 (22%) treated infants died. Death from respiratory failure occurred in 13 infants; sepsis occurred in six infants (7.8%) and contributed to death in one. During steroid therapy systemic hypertension occurred in 18 surviving infants (30%), glucose intolerance occurred in 29 infants (38%), and marked irritability occurred in three infants (3.8%). Elevated blood pressure returned to normal and glucose intolerance resolved in all infants following discontinuation of therapy. Fifty infants were available for follow-up at a mean corrected age of 14.9 +/- 9.8 months. Twenty-two percent required rehospitalization in the first year of life for respiratory illnesses. Results of testing by Bayley Scales of Infant Development were normal in 60% of infants. Fifty percent were considered normal based on both developmental testing and physical examination. Twenty-eight percent had mild to moderate abnormalities, and 22% were severely handicapped. These follow-up results are statistically similar to those recorded in LBW infants with BPD not treated with steroids who were hospitalized during the same period. We conclude that the side effects of steroid therapy for BPD consist primarily of blood pressure elevation, glucose intolerance, and irritability. Causes of death are unchanged by steroids. The incidence of severe infection and the long-term neurologic outcome of high-risk infants with BPD are not appreciably compromised by this therapy. These data suggest that concern for steroid side effects should not prevent additional prospective investigation to determine the role of steroid therapy in the overall management of BPD.  相似文献   
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A Negro woman of the Xhosa tribe of Port Elizabeth in the Eastern Cape was found to be S--s--U--with anti-U in her serum. She had two S--s--U-- children, and her husband, father and other children all had single doses of S or s antigen. Three furhter S--s--U-- Negroes were found in a random sample of 1,000 Negro antenatal patients at Port Elizabeth.  相似文献   
127.
Bilateral total hip and knee replacement in rheumatoid arthritis patients   总被引:6,自引:0,他引:6  
Summary Between 1978 and 1983, 14 patients suffering from rheumatoid arthritis were treated by bilateral total hip and knee replacement. At the time of this follow-up study (32–92 months postoperatively) one patient had died of concomitant disease and was excluded. The postoperative results regarding pain relief, improvement in performing daily activities, and function were studied in the remaining 13 patients. A 200-point rating scale was used, which compared the pre- and postoperative findings at follow-up. All patients showed marked relief from pain, good function and a good functional score. Although walking ability did not always improve, all patients were enthusiastic.  相似文献   
128.
PET using 18F-FDG is a promising technique to monitor response in oncology. Unfortunately, a multitude of analytic methods is in use. To date, it is not clear whether simplified methods could replace complex quantitative methods in routine clinical practice. The aim of this study was to select those methods that would qualify for further assessment in a future prospective response-monitoring study by comparing results with patient outcome. METHODS: Dynamic 18F-FDG PET scans were obtained on 2 groups of patients. First, 10 patients with advanced non-small cell lung cancer (NSCLC) were scanned on consecutive days before treatment to assess test-retest variability. Second, 30 scans were obtained on 19 patients with locally advanced NSCLC as part of an ongoing response-monitoring study. These scans were analyzed by 2 observers to assess observer variability. In addition, these studies were used to compare various methods with the gold standard, full kinetic analysis (nonlinear regression [NLR]). RESULTS: Using an image-derived input function, NLR showed excellent test-retest and observer agreement confirming that it could be used as a gold standard method. From a total of 34 analytic methods, 10 showed good correlation with NLR. Taking into account the degree of complexity of the methods, 4 remain for further evaluation. CONCLUSION: The optimal method for analysis of 18F-FDG PET data was determined for several levels of complexity. Four methods need to be evaluated further to determine the optimal trade-off between simplicity and accuracy for routine clinical practice.  相似文献   
129.
ObjectiveTo address a gap between spinal cord injury (SCI) research and practice by rigorously and systematically co-developing integrated knowledge translation (IKT) guiding principles for conducting and disseminating SCI research in partnership with research users.DesignThe process was guided by the internationally accepted The Appraisal of Guidelines for REsearch & Evaluation (AGREE) II Instrument for evaluating the development of clinical practice guidelines.SettingNorth American SCI research system (ie, SCI researchers, research users, funders).ParticipantsThe multidisciplinary expert panel (n=17) and end users (n=35) included individuals from a North American partnership of SCI researchers, research users, and funders who have expertise in research partnerships.InterventionsNot applicable.Main Outcome MeasuresClarity, usefulness, and appropriateness of the principles.ResultsData regarding 125 principles of partnered research were systematically collected from 4 sources (review of reviews, scoping review, interviews, Delphi consensus exercise). A multidisciplinary expert panel held a 2-day meeting to establish consensus, select guiding principles, and draft the guidance. The panel reached 100% consensus on the principles and guidance document. The final document includes a preamble, 8 guiding principles, and a glossary. Survey data showed that the principles and guidance document were perceived by potential end users as clear, useful, and appropriate.ConclusionsThe IKT Guiding Principles represent the first rigorously co-developed, consensus-based guidance to support meaningful SCI research partnerships. The principles are a foundational tool with the potential to improve the relevance and impact of SCI research, mitigate tokenism, and advance the science of IKT.  相似文献   
130.
OBJECTIVES: African Americans with acute coronary syndromes receive cardiac catheterization less frequently than whites. The objective was to determine if such disparities extend to acute evaluation and non interventional treatment. METHODS: Data on adults with chest pain (N = 7,935) presenting to eight emergency departments (EDs) were evaluated from the Internet Tracking Registry of Acute Coronary Syndromes. Groups were selected from final ED diagnosis: 1) acute myocardial infarction (AMI), n = 400; 2) unstable angina/non-ST-elevation myocardial infarction (UA/NSTEMI), n = 1,153; and 3) nonacute coronary syndrome chest pain (non-ACS CP), n = 6,382. American College of Cardiology/American Heart Association guidelines for AMI and UA/NSTEMI were used to evaluate racial disparities with logistic regression models. Odds ratios (ORs) were adjusted for age, gender, guideline publication, and insurance status. Non-ACS CP patients were assessed by comparing electrocardiographic (ECG)/laboratory evaluation, medical treatment, admission rates, and invasive and noninvasive testing for coronary artery disease (CAD). RESULTS: African Americans with UA/NSTEMI received glycoprotein IIb/IIIa receptor inhibitors less often than whites (OR, 0.41; 95% CI = 0.19 to 0.91). African Americans with non-ACS CP underwent ECG/laboratory evaluation, medical treatment, and invasive and noninvasive testing for CAD less often than whites (p < 0.05). Other nonwhites with non-ACS CP were admitted and received invasive testing for CAD less often than whites (p < 0.01). African Americans and other nonwhites with AMI underwent catheterization less frequently than whites (OR, 0.45; 95% CI = 0.29 to 0.71 and OR, 0.40; 95% CI = 0.17 to 0.92, respectively). A similar disparity in catheterization was noted in UA/NSTEMI therapy (OR, 0.53; 95% CI = 0.40 to 0.68 and OR, 0.68; 95% CI = 0.47 to 0.99). CONCLUSIONS: Racial disparities in acute chest pain management extend beyond cardiac catheterization. Poor compliance with recommended treatments for ACS may be an explanation.  相似文献   
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