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101.
102.
Although current evidence supporting a more precise strategy for identifying patients at highest risk for sudden cardiac death (SCD) is sparse, strategies for translating existing and future evidence into clinical practice and policy are needed today. A great many unanswered questions exist. Examples include the following: At what level of risk for SCD should we pursue further testing or therapy? How should clinical strategies ethically and economically balance alternative outcomes? How can we best translate optimal strategies into clinical practice so as to prevent tomorrow's SCDs? On July 20 and 21, 2006, a group of individuals with expertise in clinical cardiovascular medicine, biostatistics, economics, and health policy was joined by government (Food and Drug Administration; Centers for Medicare and Medicaid Services; National Heart, Lung, and Blood Institute; Agency for Healthcare Research and Quality), professional societies (Heart Rhythm Society), and industry to discuss strategies for risk assessment and prevention of SCD. The meeting was organized by the Duke Center for the Prevention of Sudden Cardiac Death and the Duke Clinical Research Institute. This article, the second of 2 documents, summarizes the policy discussions of that meeting, discusses an analytic framework for evaluating the risks and benefits associated with SCD prevention and risk stratification, and addresses the translation of SCD risk assessment strategies into practice and policy.  相似文献   
103.
PURPOSE: To study the possible causes of intra-operative metaphyseal fractures in elderly patients undergoing hemiarthroplasty for displaced intracapsular femoral neck fracture. METHODS: 36 men and 228 women aged 61 to 89 years with 273 displaced femoral neck fractures underwent hemiarthroplasty using a hydroxyapatite ceramic-coated Furlong bipolar prosthesis. Anteroposterior and lateral radiographs were taken immediately after surgery to evaluate the presence and type of any intra-operative fractures (classified according to the Vancouver system) and their effect on stem stability or osseointegration. Pain and clinical outcomes were evaluated using a visual analogue scale and the Harris Hip Score. RESULTS: Regarding the 273 surgeries for displaced femoral neck fracture, 28 (10%) were associated with intra-operative metaphyseal fracture (21 Vancouver type AL and 7 type AG). There was a correlation between intra-operative metaphyseal fractures and stem size. A size-9 stem was used in 64 surgeries without any fracture. A size-10 stem was used in 129 surgeries in which 11 (9%) sustained fractures, and a size-12 stem was used in 80 surgeries in which 17 (21%) sustained fractures. Postoperatively, 25 cases developed hip-related problems (thigh pain=14 and periprosthetic fractures=8) after 3 to 18 months. No patient whose metaphyseal fracture was fixed had hip problems. CONCLUSION: In elderly women with compromised bone quality, extra care is needed to achieve better fitting so as to avoid iatrogenic metaphyseal fractures. Under-sizing or cementing of the prosthesis is recommended when encountering difficulties.  相似文献   
104.
The present study aims to identify (1) what proportion of abstracts of clinical trials presented at The American Society for Laser Medicine and Surgery (ASLMS) annual meetings are published as full reports, (2) time to publication, and (3) factors that may predict the publication of research in peer-reviewed journals. Two investigators independently hand-searched all abstracts of the ASLMS meetings to identify all reports of clinical trials. Details of sample size, the country of origin, topic of research, type of presentation, type of laser, direction of outcome, and statistical significance were recorded for each abstract. To determine the full publication status of each study, The Cochrane Central Register of Controlled Trials, PubMed, and EMBASE was searched. A total of 198 abstracts were identified. Of these, 87 abstracts (44%) have been fully published. The average time from presentation at the meeting to full publication was 57 months (95% confidence interval = 52-61), and the estimated rate of abstracts published at 1, 2, and 4 years was 15, 30, and 38%, respectively. There is significant tendency for being fully published in high-power laser studies, with USA as country of origin, and orally presented. Our findings supports this opinion that conference abstracts can be an important source for systematic reviews and failure to identify trials presented in congresses might threaten the validity of systematic reviews.  相似文献   
105.
Grading severity of AS in AF is complicated by varying stroke volumes associated with fluctuating maximum velocities and pressure gradients across the aortic valve. Current guidelines recommend averaging five continuous‐wave peak velocity and mean gradient (MG) Doppler signals across the aortic valve when estimating severity of AS in AF. However, it is unknown when grading severity of AS how the average of multiple Doppler signals vs the highest Doppler signal in AF compares to the Doppler signals when the patient is in normal sinus rhythm. We present a series of patients with AS who had two echocardiograms performed within 2‐4 months of each other, one when in normal sinus rhythm and one when in AF, and compare the aortic valve hemodynamics associated with the two rhythms.  相似文献   
106.
The aim of the present study was to investigate the effect of exposure to a microcystin (MC)-containing extract from a cyanobacteria bloom on growth, development, mineral nutrient accumulation, and photosynthetic activity of Triticum durum, Zea mays, Pisum sativum and Lens esculenta cultivars. The MCs in the extract, identified by HPLC and/or mass spectrometry (MS) were: MC-RR, -LR, -YR, -(H4)YR, -WR, and -FR. Plant growth and development was tested along 30 exposure days. After this period, MC-extract caused a clear reduction in plant growth and productivity, as well as deleterious effects on development and Photosystem II activity, measured by Fv/Fm fluorescence. However, the chlorophyll (a + b) content hardly varied, and the accumulation of Na+, K+, Ca2+, P and N was enhanced. All the effects observed were plant species, MC concentration, and exposure-time dependent. Relative accumulation of each MC variant greatly varied among plant species and plant organ. The data obtained supports the idea that the use of surface water containing MCs for crop irrigation can affect both plant yield and quality, and secondly, that MC accumulation in edible plants might pose a potential risk for human and animal health, if the MC intake exceeded the recommended tolerable limits.  相似文献   
107.
BACKGROUND: Adenomas are rarely diagnosed in the appendix and may be isolated or may coexist with other neoplasms in the gastrointestinal tract. This emphasizes the need for postoperative colonoscopy when a polyp of the appendix is found. Moreover, the polyps are considered to be premalignant lesions. AIM: Report two new cases of adenomas of the appendix. CASES: We report the cases of 23-year-old and 22-year-old men, for whom appendicectomy performed for acute appendicitis. In both cases, histologic studies revealed adenomas in moderate dysplasia ; colonoscopy did not reveal any polyps.  相似文献   
108.
Treatment for cerebral palsy depends upon the severity of the child’s condition and requires knowledge about upper limb disability. The aim of this study was to develop a systematic quantitative classification method of the upper limb disability levels for children with spastic unilateral cerebral palsy based on upper limb movements and muscle activation. Thirteen children with spastic unilateral cerebral palsy and six typically developing children participated in this study. Patients were matched on age and manual ability classification system levels I to III. Twenty-three kinematic and electromyographic variables were collected from two tasks. Discriminative analysis and K-means clustering algorithm were applied using 23 kinematic and EMG variables of each participant. Among the 23 kinematic and electromyographic variables, only two variables containing the most relevant information for the prediction of the four levels of severity of spastic unilateral cerebral palsy, which are fixed by manual ability classification system, were identified by discriminant analysis: (1) the Falconer index (CAI E ) which represents the ratio of biceps to triceps brachii activity during extension and (2) the maximal angle extension (θ Extension,max). A good correlation (Kendall Rank correlation coefficient = ?0.53, p = 0.01) was found between levels fixed by manual ability classification system and the obtained classes. These findings suggest that the cost and effort needed to assess and characterize the disability level of a child can be further reduced.  相似文献   
109.
AIM: To study the frequency of vitamin D deficiency in patients with hepatitis C virus(HCV) infection and to evaluate the role of vitamin D supplementation in improving antiviral therapy.METHODS: Sixty-six children aged from 7-14 years(mean ± SD, 11.17 ± 2.293) diagnosed with HCV infection were matched to 28 healthy controls. Serum levels of 25(OH) D3, calcium, phosphorus, alkaline phosphatase and plasma level of parathormone were measured. Quantitative PCR for HCV was performed Bone density was determined by dual energy X-ray absorptiometry. All cases received conventional therapy, and only 33 patients received vitamin D supplementation.RESULTS: Children with HCV showed significantly increased levels of HCV RNA(P 0.001), parathormone(P 0.01) and decreased vitamin D levels(P 0.05)(33.3% deficient and 43.3% insufficient) compared with controls. Abnormal bone status(Z score-1.98 ± 0.75) was found in ribs, L-spine, pelvis and total body. Cases treated with vitamin D showed significant higher early(P 0.04) and sustained(P 0.05) virological response. There was a high frequency of vitamin D deficiency among the Egyptian HCV children, with significant decrease in bone density. The vitamin D level should be assessed before the start of antiviral treatment with the correction of any detected deficiency. CONCLUSION: Adding vitamin D to conventional Peg/RBV therapy significantly improved the virological response and helped to prevent the risk of emerging bone fragility.  相似文献   
110.
Rationalizing has become a new trend in the world of science and technology. Nanotechnology has ascended to become one of the most favorable technologies, and one which will change the application of materials in different fields. The quality of dental biomaterials has been improved by the emergence of nanotechnology. This technology manufactures materials with much better properties or by improving the properties of existing materials. The science of nanotechnology has become the most popular area of research, currently covering a broad range of applications in dentistry. This review describes the basic concept of nanomaterials, recent innovations in nanomaterials and their applications in restorative dentistry. Advances in nanotechnologies are paving the future of dentistry, and there are a plenty of hopes placed on nanomaterials in terms of improving the health care of dental patients.  相似文献   
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