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Purpose: Detection of body stuffers is challenging in emergency departments. Because of the small size of baggies, plain radiograph is of little value in most suspects. On the other hand, abdomen CT scan is burdened by high cost and radiation dose. This study was performed to compare the image quality, radiation dose and accuracy of low-dose CT scan in comparison with standard dose.

Material and methods: In this prospective study, suspected body stuffers who were referred to the radiology department underwent two different protocols of abdominal non-contrast CT scan simultaneously: low-dose (with equivalent dose to conventional abdominal x-ray) and standard dose. Standard dose CT scan was considered as the reference. Low-dose CT scans were evaluated for detection of baggies by two radiologists blinded to the result of standard dose CT. Image quality, noise, dose-length product (DLP) and effective dose (ED) compared between two groups.

Results: The study consisted of 40 patients (33.38?±?7.4 years). Standard dose CT evaluation was positive in 22 patients (55%). In comparison with standard dose CT scan, low-dose group had a sensitivity of 86%, specificity of 100%, PPV and NPV of 100% and 86%. The accuracy of low-dose CT scan for detection of baggies larger than 1?cm was 100%. However, from the 3 cases that could not be detected with low dose protocol, one had CT features suspected for baggies rupture which was intubated and later deceased. Noise average of low-dose protocol, was approximately 7 times greater than standard dose group, while DLP and ED were 9.7 times less.

Conclusion: Low dose CT scan appears to be an appropriate screening method for body stuffers, especially when the baggies are larger than one centimeter. However, in the presence of severe clinical symptoms, a standard dose CT scan will be more helpful due to better image quality especially in suspected ruptured baggies.  相似文献   
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Microalbuminuria is a sensitive marker to detect early nephropathy in diabetes mellitus. Cystatin C correlates better than serum creatinine with microalbuminuria in type 1 diabetes mellitus (T1D). We evaluated the correlation between microalbuminuria, serum cystatin C (Cyc-C), and serum creatinine (SCr) in diabetic children. A hundred patients with stable T1D and 66 sex-matched healthy children were entered in the study between September 2008 and February 2011. Fasting blood sample was drawn for HbA1C, creatinine, and cystatin C. A. 24-h urine aliquot was collected to measure microalbumin, creatinine, and volume. Glomerular filtration rate estimated based on creatinine (eGFRcr), cystatin C (eGFRCyst C), and creatinine + cystatin C (eGFRCyst C + Cr). Binary logistic regression analysis, chi-square, ANOVA, Student’s t test, and nonparametric median tests were used to analyze data. P < 0.05 was considered significant. Medians serum creatinine and cystatin C of T1D group were significantly different from controls (P < 0.05). Overall, medians eGFRCyst C were higher than eGFRcr, or eGFRCyst C + Cr. Thirty-six children with T1D had microalbuminuria. There was a correlation between microalbuminuria and eGFRCyst C (<60 and >130 ml/min/1.73 m2) (P < 0.05). Medians eGFRcr were significantly lower than medians eGFRCyst C in T1D, regardless of microalbuminuria (P < 0.05). Chronic kidney disease classification according to eGFRcr and eGFRCyst C were not matched (P < 0.05). GFR in healthy children was overestimated by eGFRCyst C and underestimated by eGFRcr. There was higher correlation between abnormal eGFRCyst C and microalbuminuria in diabetic children. eGFRCr detected higher rate of GFR less than 60 ml/min/1.73 m2.

  相似文献   
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Background

Cyclosporine A (CsA)-induced hepatotoxicity could be due to a reduction in α2β1 integrin expression that may either be from the direct effect of CsA itself or from reactive oxygen species (ROS) overproduction.

Objectives

In this study we aimed to identify the cellular mechanisms underlying CsA-induced hepatic injury by investigating the activation patterns of the antioxidant enzymes, using HepG2 as an in vitro model.

Materials and Methods

HepG2 cells were cultured with different concentrations of CsA (0, 0.1, 1, 10 μg/ml) for 72 h. Effect of CsA on, 1) cellular integrity, 2) glutathione reductase (GR) and glutathione peroxidase (GPx) activity, 3) cellular levels of glutathione (GSH), 4) intracellular ROS, 5) ALT and AST activities, 6) urea production and 7) α2β1 integrin expression were assayed.

Results

CsA treatment demonstrated a dose dependent increase in intracellular levels of ROS, GPx activity and decrease in GSH levels (P<0.05). GR activity was mildly attenuated in 1 and 10 µg/ml concentrations of CsA. Alanine aminotranferase (ALT) and aspartate aminotransferase (AST) levels increased in CsA treated cells, while urea synthesis was significantly decreased following treatment with higher concentrations of CsA (P<0.05). Significant down-regulation of β1integrin expression was observed in 1 and 10 µg/ml CsA treated cells while α2 integrin mRNA was significantly down-regulated in all CsA treated cells.

Conclusions

The observed reduction of α2β1 integrin expression following CsA treatment could be proposed as a possible pathway of CsA-induced hepatotoxicity. Further studies are required to elucidate whether this attenuated expression is due to the direct effect of CsA or caused by overproduction of ROS.  相似文献   
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Purpose

Few studies have evaluated prostate cancer oncologic outcomes in different ethnic groups following radical prostatectomy for clinically organ-confined disease. Existing studies lack long-term outcome data. We conducted this study to assess the impact of racial differences on risk profile and oncologic outcomes in a large cohort of patients with prostate cancer who underwent radical prostatectomy.

Methods

Using our institutional review board-approved prostate cancer database, we retrospectively reviewed the records of 3437 patients who underwent radical prostatectomy with curative intent in our institution between 1987 and 2009. Based on ethnicity, patients were divided into Asian Americans (n?=?133), African Americans (n?=?155) and Caucasians (n?=?3149). Baseline characteristics and oncologic outcomes including biochemical recurrence free, clinical recurrence free and overall survival were compared between the study groups.

Results

A total of 3437 patients with a mean age of 63?±?9.8 years and median follow-up period of 8.7 (range 0.1–24.1) years were included in the analysis. Pathologic stage and the frequency of poorly differentiated cancer were higher in Asian Americans; however, margin status did not differ significantly. Moreover, oncologic outcomes were comparable between different ethnic groups. In multivariate analysis, both pathologic stage and grade were independent predictors of oncologic outcomes, but race was not.

Conclusions

In this large, ethnically diverse long-term follow-up study, we noted that Asian Americans compared to African Americans and Caucasians are more likely to have high risk prostate cancer; however, race was not an independent predictor of oncologic outcome following radical prostatectomy with curative intent.
  相似文献   
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