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91.
We attempt to demonstrate that physicians overdiagnose loxoscelism (colloquially known as 'brown recluse spider bites') by comparing the numbers of such diagnoses to the historically known numbers of Loxosceles spiders from the same areas in four western American states. The medical community from non-endemic Loxosceles areas often makes loxoscelism diagnoses solely on the basis of dermonecrotic lesions where Loxosceles spiders are rare or non-existent. If these diagnoses were correct then Loxosceles populations should be evident, specimens should readily be collected over the years and there should be a reasonable correlation between diagnoses and spider specimens. In 41 months of data collection, we were informed of 216 loxoscelism diagnoses from California, Oregon, Washington and Colorado. In contrast, from these four states, we can only find historical evidence of 35 brown recluse or Mediterranean recluse spiders. There is no consistency between localities of known Loxosceles populations and loxoscelism diagnoses. There are many conditions of diverse etiology that manifest in dermonecrosis. In the western United States, physician familiarity with these conditions will lead to more accurate diagnoses and subsequent proper remedy.  相似文献   
92.
BACKGROUND: Combined modality therapy (CMT) is the standard of care for patients with unresectable stage III non-small-cell lung cancer (NSCLC); however, insufficient data are available regarding prognostic factors in this disease setting. PATIENTS AND METHODS: Six hundred and ninety-four patients included in five trials conducted by the Cancer and Leukemia Group B evaluating CMT in stage III NSCLC were included in this analysis. The primary objective was to identify factors that were predictors of survival and selected radiation-related toxicities using Cox regression models and logistic regression analysis. RESULTS: The Cox model shows that performance status (PS) 1 [hazard ratio (HR) 1.24; 95% confidence interval (CI) 1.06-1.45; P=0.009] and thoracic radiation therapy (TRT) only (HR 1.58; 95% CI 1.22-2.05; P=0.001) predicted for poorer survival, while baseline hemoglobin >/=12 g/dl predicted for improved survival (HR 0.67; 95% CI 0.55-0.81; P 5% weight loss (OR 2.9; 95% CI 1.3-6.6; P=0.008) and patients receiving concurrent chemoradiation (OR 7.3; 95% CI 3.4-15.6; P=0.0001). CONCLUSIONS: Baseline hemoglobin and PS, as well as the use of CMT, have the greatest effect on survival in unresectable stage III NSCLC. The use of concurrent chemoradiation increases the risk of esophagitis, which remains the primary radiation-related toxicity.  相似文献   
93.
Crawford ED 《Urology》2000,55(3):395-396
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94.
OBJECTIVES: The determination of the percentage of free prostate-specific antigen (%fPSA) enhances the specificity of prostate cancer (CaP) detection. This study was undertaken to assess the performance of %fPSA in differentiating benign prostate disease from CaP and to determine the CaP probability estimates using the AxSYM Free PSA and AxSYM Total PSA assays. METHODS: In this prospective study, 297 men, 50 years old or older, with a total PSA level between 4 and 10 ng/mL and a nonsuspicious digital rectal examination were enrolled at 10 clinical sites. All subjects underwent at least sextant prostate biopsies to establish the diagnosis. fPSA and total PSA (tPSA) levels were determined using the AxSYM Free PSA and AxSYM Total PSA assays. Percent fPSA values were compared with tPSA values to determine the appropriate cutoffs for prostate biopsy and to calculate the CaP probability estimates. RESULTS: The strongest predictor of CaP in a logistic regression model was %fPSA (odds ratio 2.29), which contributed significantly more than age or tPSA to the predictive model. In this study population, a %fPSA cutoff of 26.4% would have detected 96% of subjects with CaP (sensitivity) and would have eliminated 27.4% of unnecessary biopsies (specificity). CaP probability estimates ranged from 9% to 69% and increased as the %fPSA value decreased. Men with a %fPSA level of 10% or lower had a 69% probability of CaP, and men with a %fPSA level of greater than 26% had a 9% probability of CaP. CONCLUSIONS: Percent fPSA values can help differentiate CaP from benign prostate disease and reduce unnecessary biopsies in 27% of men 50 years old or older whose digital rectal examination was normal and whose tPSA level was between 4 and 10 ng/mL. A %fPSA result can assist the physician and patient in determining the probability of CaP and assessing the need for prostate biopsy.  相似文献   
95.
The laboratory and clinical investigation of hematopoietic growthfactors has had a profound impact on the practice of oncologyand the care of cancer patients [1]. In studies with these agents,we have learnt not only about the biological effects these agentshave on the hematopoietic system, but also about the clinicalbenefit that occurs by reducing treatment-related anemia, neutropeniaand thrombocytopenia. With regard to the colony-stimulatingfactors (G-CSF, GM-CSF) our knowledge base continues to growand guidelines for clinical use continue to undergo revision[2]. In addition to reducing the toxicity of myelosuppressivechemotherapy for millions of cancer patients, these agents havealso been integral to the study of chemotherapy dose intensityand dose density. The science of stem cells has been heavilydependent on the study of the hematopoietic cytokines and theirregulation and interaction. As a  相似文献   
96.
PURPOSE: This retrospective study was undertaken to assess practice patterns in adjuvant chemotherapy for early-stage breast cancer (ESBC) and to define the incidence and predictive factors of reduced relative dose-intensity (RDI). PATIENTS AND METHODS: A nationwide survey of 1,243 community oncology practices was conducted, with data extracted from records of 20,799 ESBC patients treated with adjuvant chemotherapy. Assessments included demographic and clinical characteristics, chemotherapy dose modifications, incidence of febrile neutropenia, and patterns of use of colony-stimulating factor (CSF). Dose-intensity was compared with published reference standard regimens. RESULTS: Dose reductions > or =15% occurred in 36.5% of patients, and there were treatment delays > or =7 days in 24.9% of patients, resulting in 55.5% of patients receiving RDI less than 85%. Nearly two thirds of patients received RDI less than 85% when adjusted for differences in regimen dose-intensity. Multivariate analysis identified several independent predictors for reduced RDI, including increased age; chemotherapy with cyclophosphamide, methotrexate, and fluorouracil, or cyclophosphamide, doxorubicin, and fluorouracil; a 28-day schedule; body-surface area greater than 2 m2; and no primary CSF prophylaxis. CSF was often initiated late in the chemotherapy cycle. CONCLUSION: Patients with ESBC are at substantial risk for reduced RDI when treated with adjuvant chemotherapy. Patients at greatest risk include older patients, overweight patients, and those receiving three-drug combinations or 28-day schedules. Predictive models based on such risk factors should enable the selective application of supportive measures in an effort to deliver full dose-intensity chemotherapy.  相似文献   
97.
98.
Sirenomelia, also known as the mermaid syndrome, is a rare congenital malformation of uncertain etiology. It is characterized by fusion of the lower limbs and commonly associated with severe urogenital and gastrointestinal malformations. In this report, we describe the first case of an infant with sirenomelia and a massive angiomatous lumbosacral myelocystocele.  相似文献   
99.
OBJECTIVE: Increased systemic levels of the bioactive peptide endothelin 1 during and after cardioplegic arrest and cardiopulmonary bypass have been well documented. However, endothelin 1 is synthesized locally, and therefore myocardial endothelin 1 production during and after cardiopulmonary bypass remains unknown. METHODS: Pigs (n = 11) were instrumented for cardiopulmonary bypass, and cardioplegic arrest was initiated. Myocardial interstitial and systemic arterial levels of endothelin 1 were measured before cardiopulmonary bypass, throughout bypass and cardioplegic arrest (90 minutes), and up to 90 minutes after separation from bypass. Myocardial interstitial endothelin 1 was determined by microdialysis and radioimmunoassay. RESULTS: Baseline myocardial endothelin 1 levels were higher than systemic endothelin 1 levels (25.6 +/- 6.7 vs 8.3 +/- 1.1 fmol/mL, P <.05). With the onset of bypass, myocardial endothelin 1 increased by 327% +/- 92% from baseline (P <.05), which preceded the increase in systemic endothelin 1 levels. CONCLUSION: Myocardial compartmentalization of endothelin 1 exists in vivo. Cardiopulmonary bypass and cardioplegic arrest induce temporal differences in endothelin 1 levels within the myocardial interstitium and systemic circulation, which, in turn, may influence left ventricular function in the postbypass period.  相似文献   
100.
Objectives: To evaluate the effect of extra‐corporeal (cardiopulmonary) bypass on hearing during coronary artery bypass grafting. Design: Prospective (single‐blinded) controlled study. Setting: District General Hospital. Participants: Fifty‐two patients undergoing coronary artery bypass grafting completed this study. Comparison was made between 14 control patients undergoing off‐pump coronary artery bypass grafting and 38 study patients undergoing on‐pump coronary artery bypass grafting. The age range of patients was 48–81 years, with 50% between 64 and 66 years. Main outcome measures: Pure tone audiograms were performed in all patients before and after coronary artery bypass grafting. Data were analysed for any significant difference between pre‐ and post‐operative pure tone audiograms. Results: Mann–Whitney U‐test demonstrated no difference between the area generated between mean pre‐ and post‐operative audiograms (P = 0.754). No significant difference between off versus on pump was demonstrated for average differences at 250–500 Hz, 4 kHz, 4–8 kHz and 8 kHz. Wilcoxon matched‐pairs signed‐rank test demonstrated no difference between right and left ears for each individual frequency. Spearman's test to analyse the effect on vessel number or minutes on bypass pump revealed no significant difference at 4–8 kHz (P = 0.550 for number of vessels and P = 0.276 for minutes on pump.) Conclusion: In this study, it was not possible to demonstrate any statistically significant deleterious effect of extra‐corporeal (cardiopulmonary) bypass on hearing during coronary artery bypass grafting.  相似文献   
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