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51.
OBJECTIVE: The Lee-risk index [Lee-index] was developed to predict major adverse cardiac events [MACE]. However, age is not included as a risk factor. The aim was to assess the value of the Lee-index in vascular surgery patients among different age categories. METHODS: Of 2642 patients cardiovascular risk factors were noted to calculate the Lee-index. Patients were divided into four age categories; < or = 55 (n=396), 56-65 (n=650), 66-75 (n=1058) and > 75 years (n=538). Outcome measures were postoperative MACE (cardiac death, MI, coronary revascularization and heart failure). The performance of the Lee-index was determined using C-statistics within the four age groups. RESULTS: The incidence of MACE was 10.9%, for Lee-index 1, 2 and > or = 3; 6%, 13% and 20%, respectively. However, the prognostic value differed among age groups. The predictive value for MACE was highest among patients under 55 year (0.76 vs 0.62 of patients aged > 75). The prediction of MACE improved in elderly (aged > 75) after adjusting the Lee-index with age, revised risk of operation (low, low-intermediate, high-intermediate and high-risk procedures) and hypertension (0.62 to 0.69). CONCLUSION: The prognostic value of the Lee-index is reduced in elderly vascular surgery patients, adjustment with age, risk of surgical procedure, and hypertension improves the Lee-index significantly.  相似文献   
52.
Abstract: We have analyzed the plasma pharmacokinetics of busulfan in 272 patients receiving high-dose oral busulfan and intravenous cyclophosphamide in conjunction with allogeneic or autologous bone marrow transplantation. The patients ranged in age from 2 months to 59 yr (mean 10, median 12 yr) and had the following diagnoses: thalassemia or sickle cell anemia (n = 74); leukemia or myelodysplasia (n = 112); inborn errors of metabolism (n = 41) or immunodeficiency (n = 45). Plasma specimens were collected following the first dose for each patient which ranged from 1 to 4 mg/kg (mean ± SD, 1.21 ± 0.41, median 1.15). Busulfan was quantitated using ultraviolet absorbance detection after derivatization and HPLC separation. Pharmacokinetic parameters were derived by modeling the raw data to fit first-order single compartment kinetics. The kinetic parameters showed wide interpatient variability independent of age and diagnosis. There was a statistically significant correlation of age with the following parameters: area under the curve (AUC); maximal concentration; minimum concentration; clearance; volume of distribution and absorption half-time. The coefficients of determination (i.e. correlation coefficient squared) were low ranging from 0.04 to 0.12 implying only a small part (i.e. 4–12%) of the variance was explained by age. Although busulfan pharmacokinetics are age-related most of the variability is not explained by age or diagnosis.  相似文献   
53.
Finzi Eric  MD  PhD    Spangler Amy  MPAS  PA-C 《Dermatologic surgery》2005,31(8):916-922
Background. Redundant facial and neck skin is a major feature of aging and historically has been corrected surgically. Recently, monopolar radiofrequency application has been introduced for nonablative tissue tightening of skin by volumetric heating of the deep dermis. It has been able to improve neck and cheek laxity and periorbital rhytides and to elevate eyebrows. However, questions remain as to the ideal parameters needed to optimize the use of radiofrequency.
Objective. To determine the safety and report on the efficacy of a radiofrequency application that involves a multipass vector (mpave) technique to target facial and neck skin laxity.
Methods. Twenty-five patients (skin types I to V) with mild to severe facial and neck laxity received one treatment session with monopolar radiofrequency. Treatment parameters, adverse events, and digital photographs were recorded. All patients were treated with a multipass vector technique consisting of four to five passes targeted over areas of skin that would most improve facial laxity. The multipass vector (mpave) treatment approach is described. Energy levels ranged from 62 to 91 J/cm2 per pulse.
Results. All patients experienced some immediate erythema and edema, which had completely resolved in most patients within 48 hours. No scarring or dyspigmentation was noted on follow-up at 6 and 12 weeks. Photographic analysis of pre- and post-treatment digital images revealed cosmetic improvement in facial and neck laxity in 96% of patients. The majority of patients demonstrated a moderate or better improvement. Stacked pulses in the submental region were shown to reduce fat.
Conclusions. The direct application of monopolar radiofrequency to facial and neck skin using a multipass vector (mpave) treatment approach was safely tolerated in patients of all skin types. Patient satisfaction correlated well with photographic analysis, and the technique was shown to be efficacious for most patients.  相似文献   
54.
The objective of the study was to conduct a process and outcomes evaluation of the International AIDS Conference (IAC). Reaction evaluation data are presented from a delegate survey distributed at the 2004 IAC held in Thailand. Input and output data from the Thailand IAC are compared to data from previous IACs to ascertain attendance and reaction trends, which delegates benefit most, and host country effects. Outcomes effectiveness data were collected via a survey and intercept interviews. Data suggest that the host country may significantly affect the number and quality of basic science IAC presentations, who attends, and who benefits most. Intended and executed HIV work‐related behavior change was assessed under 9 classifications. Delegates who attended 1 previous IAC were more likely to report behavior changes than attendees who attended more than 1 previous IAC. The conference needs to be continually evaluated to elicit the required data to plan effective future IACs.  相似文献   
55.
BACKGROUND: Research studies have focused attention on the importance of the comorbidity of personality disorders and depression. METHODS: The present review examines seven potential explanations for the overlap to clarify the nature of the relationship, if any, between depression and personality disorder diagnoses. RESULTS: There may be many explanations for the potential overlap of personality disorders (PD) and major depressive disorder (MDD). For example, the distinction between states and traits may not be as clear and definitive as suggested in the DSM-IV. In some cases, depression may influence personality pathology, and may even lead to personality disorders. In other cases, personality disorders may lead to MDD. CONCLUSION: Further research may clarify the nature of the relationship, if any, between depression and personality disorder diagnoses, as well as the relationship between comorbidity and treatment response.  相似文献   
56.
57.
BACKGROUND: Peripheral arterial disease (PAD) is a risk factor for cardiovascular events. This study assessed the prognostic significance of repeated ankle-brachial index (ABI) measurements at rest and after exercise in patients with PAD receiving conservative treatment. METHODS: In a cohort study of 606 patients (mean age 62+/-12 years, 68% male), ABI at rest and after exercise was measured at baseline and after 1 year. Patients with reductions in ABI were divided into three equally-sized groups (minor, intermediate and major reductions) and were compared to patients without reductions. During a mean follow-up of 5+/-3 years, all-cause mortality, cardiac events, stroke and progression to kidney failure were noted. RESULTS: Death was recorded in 83 patients (14%) of which 49% were due to cardiac causes. Non-fatal myocardial infarction occurred in 38 patients (6%), stroke in 46 (8%) and progression to kidney failure in 35 (6%). By multivariate analysis, patients with major declines in resting (>20%) and post-exercise (>30%) ABI were at increased risk of all-cause mortality (HR: 3.3, 95% CI: 1.5-7.2, HR: 3.0, 95% CI: 1.4-6.4, respectively), cardiac events (HR: 3.1, 95% CI: 1.3-7.2, HR: 2.4, 95% CI: 1.1-5.6, respectively), stroke (HR: 4.2, 95% CI: 1.6-10.4, HR: 3.9, 95% CI: 1.4-10.2, respectively) and kidney failure (HR: 2.7, 95% CI: 1.1-7.5, HR: 6.9, 95% CI: 1.5-31.5, respectively), compared to patients with no declines in ABI. CONCLUSIONS: This study shows that major 1-year declines in resting and post-exercise ABI are associated with all-cause mortality, cardiac events, stroke and kidney failure in patients with PAD.  相似文献   
58.
When rural/urban differences are found in health status or health care use, it is often desirable to identify those factors (such as age, social structure, income, etc.) that influence such differences. To this end, researchers often test rural/urban differences in age, social structure, income, etc., for statistical significance. Also, researchers commonly perform multivariate analyses (such as multiple regressions) to examine rural-urban differences in the influence of various independent variables on the dependent variable of interest. Frequently, researchers discover: (1) statistically significant rural/urban differences in the independent variables (such as age, social structure, income, etc.) and (2) statistically significant rural/urban differences in the effects of these independent variables (i.e., statistically significant rural/urban differences in regression coefficients). The analysis typically stops here, without addressing the relative contributions of (1) and (2) to the rural/urban differences in the dependent variable. This paper argues that the relative contributions of (1) and (2) have important implications for the way policy-makers address rural health problems. This paper presents a method for assessing the relative contributions of differences in the independent variables and differences in regression coefficients to observed differences in the dependent variable, and illustrates the application of the method by analyzing rural/urban differences in the risk of institutionalization.  相似文献   
59.
60.
OBJECTIVE: In 1991, a randomized study was published and demonstrated that use of nonsurgical therapy (chemoradiation) provided similar survival to total laryngectomy (the gold standard) for patients with advanced-stage laryngeal cancer. The purpose of this study was to assess how treatment of advanced laryngeal cancer was influenced by such developments in non-surgical therapy. STUDY DESIGN: Patterns of care study using National Cancer Database (1985-2001). RESULTS: The percentage of advanced-stage patients treated with chemoradiation increased from 8.3% to 20.8% while the proportion treated with radiation alone decreased from 38.9% to 23.0%. Use of chemoradiation increased at a significantly faster rate after the 1991 publication at both community cancer centers and teaching research facilities. The use of total laryngectomy decreased slightly during this period. CONCLUSIONS: The use of chemoradiation increased after the 1991 publication. It was impossible to determine from the NCDB whether additional patients who could benefit from chemo-RT were not offered or did not complete this treatment option. We recommend that treatment recommendations discussed at tumor boards be recorded in cancer registries.  相似文献   
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