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21.
OBJECTIVES: We compared single-point cardiac troponin T (cTnT) measurements with parameters from serial sampling during 96 h after acute myocardial infarction with magnetic resonance imaging measured infarct mass. BACKGROUND: Contrast-enhanced magnetic resonance imaging (CE-MRI) allows exact quantification of myocardial infarct size. Clinically, measurement of cardiac biomarkers is a more convenient alternative. METHODS: The CE-MRI infarct mass was determined 4 days after primary percutaneous coronary intervention in 31 ST-segment elevation myocardial infarction (STEMI) and 30 non-ST-segment elevation myocardial infarction (NSTEMI) patients. All single-point, peak, and integrated area under the curve (AUC) cTnT values were plotted against CE-MRI infarct mass. RESULTS: All single-point and serial cTnT values were significantly higher in STEMI than in NSTEMI (p < 0.01) patients. Except for the admission values, all single-point values on any of the first 4 days, peak cTnT and AUC cTnT were found to correlate comparably well with infarct mass. Among single-point measurements, cTnT on day 4 (cTnTD4) showed highest correlation and performed as well as peak cTnT or AUC cTnT (r = 0.66 vs. r = 0.65 vs. r = 0.69). Receiver-operator characteristic analysis demonstrated that cTnTD4 >0.84 microg/l predicted infarct mass above median as well as peak cTnT >1.57 microg/l or AUC cTnT (receiver-operator characteristic for AUC: 0.839 vs. 0.866 vs. 0.893). However, estimation of infarct mass with cTnTD4, peak cTnT, and AUC cTnT was worse in patients with NSTEMI (r = 0.36, r = 0.5, r = 0.36) than in STEMI (r = 0.75 vs. r = 0.65 vs. r = 0.76). CONCLUSIONS: All single-point cTnTs, except on admission, give a good estimation of infarct size and perform as well as peak cTnT or AUC cTnT. Infarct estimation by single-point measurements, particularly cTnTD4, may gain clinical acceptance because the measurement is easy and inexpensive.  相似文献   
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Purpose: To review literature specific to the use of AAC with adults who have severe aphasia. Method: The authors reviewed studies involving AAC interventions for adults with severe aphasia. Results: Published data support the use of aided and unaided AAC with adults with severe aphasia in controlled treatment contexts. Reported gains in communication typically have not generalized to everyday settings. Conclusions: The application of AAC with persons with severe aphasia must address factors potentially limiting treatment success outside of training environments.  相似文献   
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BACKGROUND: Inhibition of platelet aggregation by clopidogrel may be insufficient in up to 30% of users. These nonresponders carry an increased risk of cardiovascular events. We reported here a simple assay to study clopidogrel responsiveness. METHODS: Electrical impedance aggregometry was performed in diluted whole blood in the presence of 5 and 20 micromol/L ADP. Some samples were incubated with 0.1 mmol/L methyl-S-adenosine monophosphate (MeSAMP), a P2Y12 receptor blocker, to maximize inhibition of aggregation before aggregometry. To validate the assay, we analyzed 6-min impedance in 21 healthy probands and 244 patients with coronary artery disease (CAD). RESULTS: At 5 micromol/L ADP, the imprecision of the assay was 11%. Mean (SD) impedance of the healthy cohort was 12.2 (2.2) Omega. The mean - 3 SD was used to define the cutoff for clopidogrel responsiveness: responders and nonresponders exhibited a 6-min impedance < or =5 Omega and >5 Omega, respectively. Samples from nonresponders were incubated with MeSAMP and analyzed again to distinguish pharmacokinetic and pharmacodynamic types of resistance. Sixteen percent of CAD patients were classified as nonresponders (38 and 2 cases of pharmacokinetic and pharmacodynamic resistance, respectively). Female sex was strongly associated with clopidogrel resistance (P = 0.0002, Fisher exact test). A higher clopidogrel loading dose (P = 0.0353, Mann-Whitney U-test) was given to responders (median, 450 mg) than nonresponders (median, 300 mg). Age and cardiovascular diagnosis showed no significant associations. CONCLUSIONS: Impedance aggregometry using 5 mumol/L ADP is a useful tool for studying clopidogrel responsiveness. MeSAMP allows characterization of responsiveness "on treatment" and may be useful for optimizing clopidogrel dosing.  相似文献   
26.
High salt (sodium chloride) consumption is an important determinant of high blood pressure and cardiovascular risk. According to World Health Organisation (WHO) statistics, over 80% of cardiovascular disease (CVD) deaths take place in low-and middle-income countries, and elevated blood pressure levels were a major cause of these CVD deaths in those countries.1 Lifestyle factors such as unhealthy diet, physical inactivity, tobacco use and harmful use of alcohol have been considered the most important behavioural risk factors for heart disease and stroke.2Among dietary factors, high salt intake has been the most strongly associated with raised blood pressure and increased risk of stroke and CVD.3 Therefore dietary sodium restriction has been recommended as a non-pharmacological approach to blood pressure lowering,4-6 and for the prevention and control of non-communicable diseases at the population level.7,8Cumulative evidence has shown that even a modest reduction in salt intake was associated with blood pressure lowering and therefore with a significant reduction in incidence of cardiovascular events.9-12 Furthermore, data from the most recent systematic review and meta-analyses has shown the benefit of lowering sodium intake in apparently healthy adults and children,13 and in both hypertensive and normotensive individuals, irrespective of gender and ethnic group.9Since hypertension is associated with CVD worldwide, a public health intervention to reduce high blood pressure must target the role of lifestyle, particularly reduced sodium intake.7 Therefore, several countries have initiated strategies to reduce dietary salt intake in the general population by a combination of various procedures such as public education, food labelling, and collaboration with the food industry to reduce the salt content of processed food.14Among sub-Saharan African countries, only Nigeria and South Africa have developed dietary guidelines regarding salt intake.15 Recently, the South African government implemented important specific legislation towards decreasing salt intake in the population by reducing sodium content of processed foods by industries.16 Therefore, the current public health recommendation is that countries should launch national initiatives to reduce the over-consumption of salt as part of non-communicable disease prevention and healthy nutrition policies for limiting salt intake to less than 5 g/day for the general population including children.7 Despite of this guideline, however, high sodium intake remains prevalent around the world, with average daily salt intake varying from 5 to 18 g/day per person.17Although processed foods have been found to be the principal source of excessive dietary salt intake,18 sources of dietary sodium vary largely worldwide and may be influenced by cultural context and dietary habits of the population.19 In sub-Saharan African countries experiencing demographic and epidemiological transition, the rapid rise in prevalence of CVD (chiefly hypertension) has been attributed to lifestyle change, including high dietary sodium intake.20,21 However, consistent data from studies on risk factors are lacking for the majority of these countries.With regard to Angola, available data from a cross-sectional study reported a high prevalence of multiple cardiovascular risk factors, such as hypertension, sedentary lifestyle, electrocardiographic left ventricular hypertrophy,22 and high rate of the metabolic syndrome23 in an apparently healthy middle-aged population of university public employees living in urban and peri-urban areas.Determining the level of sodium intake in the population is crucial to establish intervention strategies and policy on reduction of sodium intake. For medical students in particular, it is very important to assess their awareness regarding dietary salt intake, since they are the future providers of healthcare information for the counselling of people about the need to reduce salt consumption. The aim of this study was to determine salt intake and to assess the knowledge, attitude and behaviour regarding dietary salt among medical students.  相似文献   
27.
The radiographic findings in five pediatric patients in whom unregulated B-cell lymphoproliferative disorders developed following bone marrow transplantation are described. Four patients received T-cell-depleted bone marrow from mismatched donors and one received nondepleted marrow from a matched sibling donor. These disorders are similar to B-cell lymphoproliferative disorders that have been described in other immunosuppressed hosts. They are associated with Epstein-Barr virus and range from polyclonal proliferation without cytogenetic abnormalities to monoclonal lymphoma with clonal cytogenetic changes. Unlike other postallograft lymphoproliferative processes, B-cell lymphoproliferative disorders in these patients have not responded to antiviral therapy, immunologic therapy, or chemotherapy. The radiographic patterns of disease include diffuse or focal hepatic involvement; gallbladder wall thickening; and pulmonary, soft-tissue, and basal-ganglion masses. These radiologic findings are not specific and evaluation of tissue histology is required for diagnosis.  相似文献   
28.
急性呼吸窘迫综合征(acute respiraory distress syndrome,ARDS)是一种常见的严重肺功能紊乱的肺部并发症。常并发于脓毒血症、创伤和抽吸术等严重损伤后。ARDS的发生及死亡率可因发生ARDS损伤类型的不同而有差别,提示ARDS的发病机制和预后因临床风险因素而不同。最近,对重症病人进  相似文献   
29.
Purpose: To review literature specific to the use of AAC with adults who have severe aphasia. Method: The authors reviewed studies involving AAC interventions for adults with severe aphasia. Results: Published data support the use of aided and unaided AAC with adults with severe aphasia in controlled treatment contexts. Reported gains in communication typically have not generalized to everyday settings. Conclusions: The application of AAC with persons with severe aphasia must address factors potentially limiting treatment success outside of training environments.  相似文献   
30.
目的通过整合不同的患者导向的测量工具的项目来编制ICF特定类目的等距量表结构。方法使用有效的122例类风湿关节炎患者的样本资料进行心理测量研究。患者完成6个不同的以患者导向的测量工具。将这些测量工具项目的内容与ICF类目进行匹配。对项目反应等级进行Rasch分析用于检查这些测量工具项目是否说明了ICF类目b130:能量和驱力功能,从而构成一个心理测量可靠的等距量表。结果 19个项目与b130能量和驱力功能有关。根据2χ检验和Z值统计,19个项目中的16个项目拟合Rasch模型(项目和个人的ZMean=0.451,ZSD=1.085和ZMean=-0.223,ZSD=1.132)。Person分离指数rβ是0.93。结论可以构建ICF类目等距量表使得单个ICF类目可操作化。每个项目的原始格式在等距量表中保持不变。本研究在ICF的操作和将来的实施方面迈出了重要的一步。  相似文献   
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