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91.
BackgroundCurrent data regarding the risk of malignancy in a large thyroid nodule with benign fine-needle aspiration biopsy(FNAB) is conflicting. We investigated the impact of patient age on the risk of malignancy in nodules≥4 cm with benign cytology.MethodsWe performed a single-institution retrospective review of patients who underwent surgery from 07/2008–08/2019 for a cytologically benign thyroid nodule ≥4 cm. The relationship between malignant histopathology and patient and ultrasound features was assessed with multivariable logistic regression.ResultsOf 474 nodules identified, 25(5.3%) were malignant on final pathology. In patients <55 years old, 21/273(7.7%) nodules were malignant, compared to 4/201(2.0%) in patients ≥55. Patient age ≥55 was independently associated with significantly lower risk of malignancy(OR:0.2,95%CI:0.1–0.7,p = 0.011). Increasing nodule size >4 cm and high-risk ultrasound features were not associated with risk of malignancy(OR:1.0,95%CI:0.7–1.4,p = 0.980, and OR:9.6,95%CI:0.9–107.8,p = 0.066, respectively).ConclusionsPatients <55 years old are 3.7-fold more likely to have a falsely benign FNA biopsy in a nodule≥4 cm.  相似文献   
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INTRODUCTION: This study was designed to determine the value of fluorodeoxyglucose (FDG) positron emission tomography (PET) in the evaluation of metastatic transitional cell carcinoma (TCC). METHODS: Fifty-eight FDG PET scans were performed on 46 consecutive patients with TCC. Results were correlated with radiologic, pathologic, and histologic findings in these patients and the sensitivity of PET for detecting malignancy in untreated TCC patients (n = 48) was compared to the sensitivity in patients who had undergone prior chemotherapy (n = 10). RESULTS: Of 48 scans in patients who had no prior systemic chemotherapy, 10 had increased uptake in proven metastatic TCC lesions and 3 PET studies failed to reveal metastatic TCC (sensitivity 76.9%). In patients free of metastatic disease, 33 revealed no abnormal uptake and 1 study revealed a suspicious area in a patient free of metastases (specificity = 97.1%). However, in 10 patients imaged after receiving chemotherapy, the sensitivity fell to 50% for the detection of histologically confirmed residual/recurrent tumor by PET. CONCLUSIONS: FDG PET detects increased metabolic activity. After chemotherapy, viable cancer cells may still be present but with a diminished metabolic rate. As a result, PET imaging is often useful in the evaluation of untreated metastatic TCC metastasis but should be interpreted with caution in patients who have received prior chemotherapy.  相似文献   
93.
Omega‐3 (n‐3) and omega‐6 (n‐6) polyunsaturated fatty acids (PUFA) in red blood cells (RBCs) are an objective indicator of PUFA status and may be related to hip fracture risk. The primary objective of this study was to examine RBC PUFAs as predictors of hip fracture risk in postmenopausal women. A nested case‐control study (n = 400 pairs) was completed within the Women's Health Initiative (WHI) using 201 incident hip fracture cases from the Bone Mineral Density (BMD) cohort, along with 199 additional incident hip fracture cases randomly selected from the WHI Observational Study. Cases were 1:1 matched on age, race, and hormone use with non–hip fracture controls. Stored baseline RBCs were analyzed for fatty acids using gas chromatography. After removing degraded samples, 324 matched pairs were included in statistical analyses. Stratified Cox proportional hazard models were constructed according to case‐control pair status; risk of fracture was estimated for tertiles of RBC PUFA. In adjusted hazard models, lower hip fracture risk was associated with higher RBC α‐linolenic acid (tertile 3 [T3] hazard ratio [HR]: 0.44; 95% confidence interval [CI], 0.23–0.85; p for linear trend 0.0154), eicosapentaenoic acid (T3 HR: 0.46; 95% CI, 0.24–0.87; p for linear trend 0.0181), and total n‐3 PUFAs (T3 HR: 0.55; 95% CI, 0.30–1.01; p for linear trend 0.0492). Conversely, hip fracture nearly doubled with the highest RBC n‐6/n‐3 ratio (T3 HR: 1.96; 95% CI, 1.03–3.70; p for linear trend 0.0399). RBC PUFAs were not associated with BMD. RBC PUFAs were indicative of dietary intake of marine n‐3 PUFAs (Spearman's rho = 0.45, p < 0.0001), total n‐6 PUFAs (rho = 0.17, p < 0.0001) and linoleic acid (rho = 0.09, p < 0.05). These results suggest that higher RBC α‐linolenic acid, as well as eicosapentaenoic acid and total n‐3 PUFAs, may predict lower hip fracture risk. Contrastingly, a higher RBC n‐6/n‐3 ratio may predict higher hip fracture risk in postmenopausal women. © 2013 American Society for Bone and Mineral Research.  相似文献   
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96.
BACKGROUND: Macular degeneration, the end stage of age-related maculopathy (ARM), is the leading cause of legal blindness worldwide, and few modifiable risk factors are known. The high concentration of carotenoids in the macula, plus evidence linking oxidative stress to ARM and carotenoids to antioxidation, generated the hypothesis that higher antioxidant intakes can prevent ARM. Results of observational and intervention studies have been inconsistent. OBJECTIVE: To evaluate associations between intakes of zinc and antioxidant micronutrients and early ARM. METHODS: Between 1993 and 1995, ARM was assessed in 398 Boston-area women aged 53-74 y using the Wisconsin Age-related Maculopathy System of grading retinal fundus photographs. The women were a subset of the Nurses' Health Study cohort. Micronutrient intake was assessed by semi-quantitative food frequency questionnaires administered four times between 1980 and the baseline eye examinations. RESULTS: After multivariate adjustment for potential confounders, 1980 energy-adjusted intakes of alpha-carotene, beta-carotene, lycopene, total retinol, total vitamin A, and total vitamin E were significantly inversely related to the prevalence of pigmentary abnormalities (PA). Furthermore, increasing frequency of consuming foods high in alpha-or beta-carotene was associated with lower odds of PA; compared to women consuming these foods < 5 times/wk, odds ratios (95% CI) were 0.7 (0.3-1.6) for 5-6 times/wk, 0.6 (0.2-1.3) for 7-9.5 times/wk, and 0.3 (0.1-0.7)for > or =10 times/wk. Lutein/zeaxanthin intakes and more recent intakes of most carotenoids were unrelated to PA, and intakes of zinc and antioxidant micronutrients were unrelated to having large or intermediate drusen alone.  相似文献   
97.
OBJECTIVES/HYPOTHESIS: The aim of the study was to evaluate the role of combined positron emission tomography/computed tomography (PET/CT) fusion imaging in the detection and management of recurrent papillary thyroid cancer. STUDY DESIGN: A retrospective analysis of 33 patients with suspected recurrent papillary thyroid carcinoma who had undergone PET/CT was performed. PET/CT was compared with standard imaging techniques in each patient to determine whether PET/CT contributed to the therapeutic management plan. Histopathological findings were correlated to PET/CT in patients who underwent surgery. METHODS: The senior author reviewed the charts of 33 patients with recurrent papillary thyroid carcinoma to determine the impact PET/CT had on management. PET/CT was compared with conventional imaging results. In surgical patients, PET/CT was compared with histopathological findings to determine its sensitivity, specificity, accuracy, positive predictive value, and negative predictive value. RESULTS: In 67% of the cases (22 of 33), PET/CT supplied additional information that altered or confirmed the management plan. Twenty of 33 patients underwent surgery with 36 sites assessed by histopathological analysis. PET/CT correlated with histopathological findings in 25 of 36 distinct anatomical sites, with an accuracy of 70%. The sensitivity of PET/CT in identifying recurrence was found to be 66%, with a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 27%. CONCLUSION: Combined PET/CT fusion scanning was most useful in the detection and management of recurrent papillary thyroid cancer in patients who had average thyroglobulin levels greater than 10 ng/mL and when the tumor no longer concentrated radioactive iodine. In 100% of the cases in which PET/CT localized a region suspicious for malignancy, histopathological analysis confirmed the results. When PET/CT is positive, it is a powerful tool for predicting exact locations of recurrent papillary thyroid cancer, thus making it a reliable guide for surgical planning. PET/CT is a supplement to conventional imaging and fine-needle aspiration in the workup of recurrent papillary thyroid cancer. A negative finding on PET/CT is not sufficiently reliable to preclude further investigation and treatment.  相似文献   
98.
Background/Aims: Gallstone disease (GD) and cardiovascular disease (CD) are common diseases worldwide with considerable economical impact and they are strongly associated. Carotid atherosclerosis is an excellent marker of risk for CD like stroke and myocardial infarction. The aim of this study was to assess the association between gallstones and carotid atherosclerosis. Methods: A cross‐sectional study was conducted. We evaluated subjects with ultrasonographical evidence of GD and asymptomatic subjects without such evidence. Anthropometric, clinical and biochemical variables were collected. The Metabolic syndrome was evaluated using adult treatment panel III criteria. Carotid artery intima–media thickness (CIMT) was determined by a standard ultrasound protocol. Insulin‐like growth factor‐1 (IGF‐1) serum levels were measured in all subjects. Results: We studied 191 subjects: 62 subjects with GD (53.2% males) and 129 asymptomatic subjects without GD (65.9% males). Subjects with GD exhibited a higher body mass index, body fat percent, insulin serum levels and CIMT (P<0.05 for all). The prevalence of GD was higher in subjects with a CIMT>0.75 independently of other factors [odds ratio (OR) 2.12, 95% confidence interval (CI) 1.04–4.34; P=0.039], and for every 0.1 mm increase in CIMT the independent probability to be a case of GD increased by a factor of 1.25 (95% CI 1.02–1.53; P=0.027). IGF‐1 levels did not differ among groups. Conclusions: Subjects with GD exhibit greater carotid atherosclerosis, and therefore have a higher risk for stroke and myocardial infarction.  相似文献   
99.
This article describes the results of a study that used intensive direct observations of eight medical practices to assess the factors affecting the barriers and facilitators to adult immunization for influenza and pneumonia. The study aimed to describe the culture of these practices by identifying key features that facilitate or deter the immunization process. The article presents profiles of six of the eight practices describing their cultural and organizational frameworks. Six features that are critical to an understanding of the cultures of these practices, particularly as they relate to receptivity to influenza immunization for diverse practices and patient populations, are highlighted. These include policies and procedures, funding source, physician philosophy, patient receptivity to provider recommendation, and physical environment and social environment. The article also discusses strategies for applying knowledge about the culture of each practice to introduce appropriate and feasible interventions aimed at increasing immunization rates.  相似文献   
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