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101.
A series of 14 parapharyngeal tumours has been studied with regard to their symptology, pre-operative evaluation and surgical management. High resolution computed tomography is now the best initial diagnostic study because it helps to determine the size and extent of the tumour, differentiate tumours of parotid and extraparotid origin, demonstrate degree of tumour vascularity, separate benign from malignant lesions, plan the surgical approach and predict prognosis.  相似文献   
102.
A 23 years old male presented with a soft cystic mass in the left paralaryngeal space since 3 months. Indirect laryngoscopy revealed a bulging of the left lateral pharyngeal wall. Histopathologic al examination of the biopsy proved it to be a synovial sarcoma. The case is the seventh case reported in literature.  相似文献   
103.
Bias in questionnaires is an important issue in public health research. To collect the most accurate data from respondents, investigators must understand and be able to prevent or at least minimize bias in the design of their questionnaires. This paper identifies and categorizes 48 types of bias in questionnaires based on a review of the literature and offers an example of each type. The types are categorized according to three main sources of bias: the way a question is designed, the way the questionnaire as a whole is designed, and how the questionnaire is administered. This paper is intended to help investigators in public health understand the mechanism and dynamics of problems in questionnaire design and to provide a checklist for identifying potential bias in a questionnaire before it is administered.  相似文献   
104.
Measurement Issues in Health Disparities Research   总被引:3,自引:0,他引:3       下载免费PDF全文
Background. Racial and ethnic disparities in health and health care have been documented; the elimination of such disparities is currently part of a national agenda. In order to meet this national objective, it is necessary that measures identify accurately the true prevalence of the construct of interest across diverse groups. Measurement error might lead to biased results, e.g., estimates of prevalence, magnitude of risks, and differences in mean scores. Addressing measurement issues in the assessment of health status may contribute to a better understanding of health issues in cross-cultural research.
Objective. To provide a brief overview of issues regarding measurement in diverse populations.
Findings. Approaches used to assess the magnitude and nature of bias in measures when applied to diverse groups include qualitative analyses, classic psychometric studies, as well as more modern psychometric methods. These approaches should be applied sequentially, and/or iteratively during the development of measures.
Conclusions. Investigators performing comparative studies face the challenge of addressing measurement equivalence, crucial for obtaining accurate results in cross-cultural comparisons.  相似文献   
105.
BACKGROUND: Drug-drug interactions (DDIs) are a well known risk factor for adverse drug reactions. HMG-CoA reductase inhibitors ('statins') are a cornerstone in the treatment of dyslipidaemia and patients with dyslipidaemia are concomitantly treated with a variety of additional drugs. Since DDIs are associated with adverse reactions, we performed a cross-sectional study to assess the prevalence of potentially critical drug-drug and drug-statin interactions in an outpatient adult population with dyslipidaemia. METHODS: Data from patients with dyslipidaemia treated with a statin were collected from 242 practitioners from different parts of Switzerland. The medication list was screened for potentially harmful DDIs with statins or other drugs using an interactive electronic drug interaction program. RESULTS: We included 2742 ambulatory statin-treated patients (mean age +/- SD 65.1 +/- 11.1 years; 61.6% males) with (mean +/- SD) 3.2 +/- 1.6 diagnoses and 4.9 +/- 2.4 drugs prescribed. Of those, 190 patients (6.9%) had a total of 198 potentially harmful drug-statin interactions. Interacting drugs were fibrates or nicotinic acid (9.5% of patients with drug-statin interactions), cytochrome P450 (CYP) 3A4 inhibitors (70.5%), digoxin (22.6%) or ciclosporin (cyclosporine) [1.6%]. The proportion of patients with a potential drug-statin interaction was 12.1% for simvastatin, 10.0% for atorvastatin, 3.8% for fluvastatin and 0.3% for pravastatin. Additionally, the program identified 393 potentially critical non-statin DDIs in 288 patients. CONCLUSIONS: CYP3A4 inhibitors are the most frequent cause of potential drug interactions with statins. As the risk for developing rhabdomyolysis is increased in patients with drug-statin interactions, clinicians should be aware of the most frequently observed drug-statin interactions and how these interactions can be avoided.  相似文献   
106.
PURPOSE: Consumer assessments of interpersonal processes of care during prenatal care provide important information about how well clinicians satisfy the perceived needs of the women they serve, but few measures are available that tap the various components of these processes. The purpose of this study is to develop a multidimensional measure of prenatal interpersonal processes of care (PIPC) that demonstrates reliability and validity in ethnically diverse women in Medicaid managed care plans. METHODS: A telephone survey of African American, Latino (U.S. and foreign born) and Caucasian pregnant women in four Medicaid managed care plans in California was conducted in English and Spanish in 2001. Factor analytic methods were used to test the PIPC measures. A psychometric evaluation, including reliability, variability, and construct validity, was conducted with the final scales for the total sample and for each racial/ethnic group. RESULTS: Three dimensions, Communication, Patient-Centered Decision Making, and Interpersonal Style, with seven scales were supported with 30 items. The scales for each dimension exhibit acceptable reliability for the total sample (Internal Consistency Reliability ranged from 0.66 to 0.85) and for all racial/ethnic groups. All scales had significant associations with satisfaction with prenatal care and explained considerable variation in satisfaction (19-43%). The scale qualities and validity associations held for all scales and ethnic groups except some scales for U.S.-born Latinas. CONCLUSIONS: The multidimensional PIPC measure for assessing what actually happens between providers and low-income pregnant women of diverse ethnic groups demonstrates acceptable reliability and construct validity.  相似文献   
107.
OBJECTIVE: To assess whether treatment with heparin alters ultrasound findings in pregnant women with inherited thrombophilia. METHODS: This was a retrospective study of a cohort of patients referred for pregnancy complications who were found to have genetic thrombophilia. Ultrasounds were reviewed in treated and untreated pregnancies for the presence of growth restriction, oligohydramnios or abnormal Doppler results. RESULTS: There were a total of 178 pregnancies in 51 patients. The overall percentage of abnormal ultrasounds was significantly greater in the untreated compared with treated pregnancies (52.8% vs. 27.9%; p = 0.024.) Growth restriction and abnormal Doppler results were more common in untreated pregnancies. There was a significantly decreased risk of oligohydramnios with treatment (27.3% vs. 7%; p = 0.03). Overall outcomes were significantly improved with the use of anticoagulation ( p < 0.0001). CONCLUSIONS: Treatment markedly improves ultrasound parameters of growth, fluid and feto-placental blood flow in patients with thrombophilia. The presence of abnormalities despite treatment reinforces the need for close antenatal surveillance.  相似文献   
108.
OBJECTIVES: Childhood obesity contributes to a wide array of medical conditions, including asthma. There is also increasing evidence in adult patients admitted to the intensive care unit (ICU) that obesity contributes to increased morbidity and to a prolonged length of stay. We hypothesized that obesity is associated with the need for increased duration of therapy in children admitted to the ICU with status asthmaticus. DESIGN: Retrospective cohort study. SETTING: A tertiary pediatric ICU in a university-affiliated children's hospital. PATIENTS: We retrospectively examined data from all children older than 2 yrs admitted to the ICU with status asthmaticus between April 1997 and June 2004. Children were classified as normal weight (<95% weight-for-age percentile) or obese (>95% weight-for-age). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of the 209 children admitted to the ICU with asthma, 45 (22%) were obese. Compared with children of normal weight, the obese children were older (9.7 +/- 4.4 vs. 8.0 +/- 4.3 yrs, p = .02), more likely to be female (60% vs. 37%, p < .01), and more likely to have been admitted to the ICU previously (40% vs. 20%, p = .01). The obese children also had a statistically significant difference in race (more likely to be Hispanic) and in baseline asthma classification (more likely to have persistent asthma). Despite similar severity of illness at ICU admission, obese children had a significantly longer ICU length of stay (116 +/- 125 hrs vs. 69 +/- 57 hrs, p = .02) and hospital length of stay (9.8 +/- 7.0 vs. 6.5 +/- 3.4 days, p < .01). Obese children also received longer courses of supplemental oxygen, continuous albuterol, and intravenous steroids. CONCLUSIONS: Childhood obesity significantly affects the health of children with asthma. Obese children with status asthmaticus recovered more slowly from an acute exacerbation, even after adjustment for baseline asthma severity and admission severity of illness.  相似文献   
109.
ACE inhibitors have significantly decreased cardiovascular mortality, myocardial infarction (MI), and hospitalizations for heart failure (HF) in patients with asymptomatic or symptomatic left ventricular (LV) systolic dysfunction. Furthermore, the extended 12-year study of the SOLVD (Studies Of Left Ventricular Dysfunction) Prevention and Treatment trials (X-SOLVD) demonstrated a significant benefit with a reduction of cumulative all-cause death compared with placebo (50.9% vs 56.4%) [hazard ratio (HR) 0.86; 95% CI 0.79, 0.93; p < 0.001]. The survival benefits and significant reductions in cardiovascular morbidity related to treatment with ACE inhibitors are likely achieved by titrating the dose of ACE inhibitors to the target dose achieved in clinical trials. Although the ATLAS (Assessment of Treatment with Lisinopril And Survival) study, which randomly allocated HF patients to low- or high-dose lisinopril, showed no significant difference between groups for the primary outcome of all-cause mortality (HR 0.92; 95% CI 0.82, 1.03), the predetermined secondary combined outcome of all-cause mortality and HF hospitalization was reduced by 15% for the patients receiving high-dose lisinopril compared with low-dose (p < 0.001) with a 24% reduction in HF hospitalization (p = 0.002). Despite the use of ACE inhibitors, blockade of the renin angiotensin aldosterone system (RAAS) remains incomplete, with evidence of continued production of angiotensin II by non-ACE-dependent pathways. The safety and potential benefits of angiotensin receptor antagonists (angiotensin receptor blockers [ARBs]) in patients with impaired systolic function have been assessed in moderate to large clinical trials. In patients with impaired LV systolic function and HF, combination therapy with ARBs with recommended HF therapy including ACE inhibitors in patients who remain symptomatic may be considered for its morbidity benefit. Based on the CHARM (Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity)-Added data, candesartan cilexetil in addition to standard HF therapy results in a further reduction of cardiovascular mortality. Close monitoring of renal function and serum potassium levels is needed in this setting. The VALIANT (VALsartan In Acute myocardial iNfarction Trial) results suggest that valsartan is as effective as captopril in patients following an acute MI with HF and/or LV systolic dysfunction and may be used as an alternative treatment in ACE inhibitor-intolerant patients. There was no survival benefit with valsartan-captopril combination compared with captopril alone in this trial. Despite these results, ACE inhibitors remain the first-choice therapeutic agent in post-MI patients, and ARBs can be used in patients with clear intolerance. Although the use of ACE inhibitors may be appealing in patients with HF and preserved LV systolic function, there is currently no evidence from large clinical trials to support this.  相似文献   
110.
The venom of the Neotropical social wasp Protopolybia exigua(Saussure) was fractionated by RP-HPLC resulting in the elution of 20 fractions. The homogeneity of the preparations were checked out by using ESI-MS analysis and the fractions 15, 17 and 19 (eluted at the most hydrophobic conditions) were enough pure to be sequenced by Edman degradation chemistry, resulting in the following sequences: Protopolybia MPI I-N-W-L-K-L-G-K-K-V-S-A-I-L-NH2 Protopolybia-MP II I-N-W-K-A-I-I-E-A-A-K-Q-A-L-NH2 Protopolybia-MP III I-N-W-L-K-L-G-K-A-V-I-D-A-L-NH2 All the peptides were manually synthesized on-solid phase and functionally characterized. Protopolybia-MP I is a hemolytic mastoparan, probably acting on mast cells by assembling in plasma membrane, resulting in pore formation; meanwhile, the peptides Protopolybia-MP II and -MP III were characterized as a non-hemolytic mast cell degranulator toxins, which apparently act by virtue of their binding to G-protein receptor, activating the mast cell degranulation.  相似文献   
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