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1.
Summary The excretion of thioethers was determined in the urine of workers involved in road paving operations and in the preparation of asphalt mixing in an asphalt plant. An occupationally nonexposed group served as control. From the results it was observed that there was no significant difference in urinary thioether levels between the exposed and nonexposed groups, however, smokers of both exposed groups had significantly higher urinary thioether levels than the nonexposed smoking workers. These results suggested that higher urinary thioether excretion could be only due to a difference in smoking behaviour. There were also significant differences in urinary thioether levels between the exposed smoking and nonsmoking workers. The authors suggest that these workers have a low mutagenic/carcinogenic risk and smoking is responsible for the majority of thioether excretion, as has been found by other investigators.  相似文献   
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The aim of this prospective study was to determine the diagnostic value of Tc-99m MDP scintimammography (SMG) for the detection of breast cancer in patients with breast masses and to compare the results with Tc-99m MIBI scintimammography. Twenty patients, categorized as suspicious, positive or benign for breast cancer according to the mammographic findings were included in the study. Dual phase Tc-99m MIBI and Tc-99m MDP SMG were performed in the prone lateral position within 5 days of each other. Although early and late Tc-99m MIBI SMG showed equal (90.4%) sensitivity, the specificity of late Tc-99m MIBI (87.5%) was found superior to early (62.5%) imaging. The overall sensitivity and specificity of early Tc-99m MDP SMG were 71.4% and 62.5%, respectively. Although late Tc-99m MDP imaging showed 100% specificity, its sensitivity was only 23.8%. In the patients with palpable masses, both early Tc-99m MDP and Tc-99m MIBI showed equal sensitivity (100%), but the sensitivity of early Tc-99m MIBI (37.5%) was found slightly higher than Tc-99m MDP (25.0%) for nonpalpable breast lesions. The sensitivity of Tc-99m MIBI and Tc-99m MDP SMG in detecting metastatic axillary involvement was 66.6% and 50%, respectively. High sensitivity and specificity together with its low cost, easy availability and the possibility of detecting bone metastases seems to make Tc-99m MDP a contributive agent in the evaluation of breast lesions as an alternative to Tc-99m MIBI.  相似文献   
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Hekimsoy  İlhan  Güler  Ezgi  Harman  Mustafa  Elmas  Nevra 《Abdominal imaging》2019,44(10):3359-3369
Purpose

To compare three chemical shift MRI techniques [two-dimensional (2D) dual gradient echo (dGRE), 3D VIBE, and 3D VIBE-Dixon] at 3 T and 2D dGRE technique at 1.5 T to assess their ability of detecting microscopic fat in adrenal adenomas and differentiating between adenomas and non-adenomas.

Methods

Seventy-eight patients with 97 lesions (78 adenomas, 19 non-adenomas) underwent both 1.5 T and 3 T chemical shift MRI. The Wilcoxon signed-ranked test was used to determine if there was significant difference between the signal intensity index (SII) values of each technique to assess their ability to detect microscopic fat in adrenal adenomas. ROC analysis was performed for the SII values of each technique, the adrenal-to-spleen SI ratio of 2D dGRE technique at 3 T, and the fat fraction values of the 3D VIBE-Dixon technique to identify the optimal threshold for differentiation of adrenal adenomas from non-adenomas.

Results

For detection of microscopic fat, the mean SII value of 2D dGRE technique at 1.5 T was significantly higher than that of the chemical shift imaging techniques at 3 T (p = 0.001). For discrimination of adenomas from non-adenomas, the area under the curve (AUC) and 95% confidence interval values of 2D dGRE technique at 1.5 T and 2D dGRE, 3D VIBE, 3D VIBE-Dixon techniques at 3 T were calculated as 1.00 (1.00–1.00), 0.991 (0.978–1.00), 0.999 (0.995–1.00), 0.993 (0.979–1.00), respectively, for the SII.

Conclusion

Chemical shift MRI at 1.5 T using the 2D dGRE technique provided the most accurate differentiation between adenomas and non-adenomas. However, there was no statistically significant difference between chemical shift imaging techniques at 1.5 T and 3 T.

  相似文献   
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INTRODUCTION

Giant cervical and mediastinal goiter may lead to acute respiratory failure caused by laryngotracheal compression and airway obstruction. Here, we present a case admitted to the emergency service with a giant goiter along with respiratory failure and poor general health status, which required urgent surgical intervention.

PRESENTATION OF CASE

A 71-year-old female admitted to the emergency room with shortness of breath and poor general health status resulting from a giant cervical swelling progressively increased during the last 7 years and constituted severe respiratory failure which has become severe in the last one month. A giant nodular goiter of the left thyroid lobe extending retrosternally, causing tracheal compression, limiting the neck movements was detected with clinical examination and bedside ultrasound. Emergency thyroidectomy was planned. Fiberoptic-assisted awake nasal intubation was performed in the operating room. Emergency total thyroidectomy was performed for the life-threatening respiratory failure. Postoperative period was uneventful. She was transferred from intensive care unit to the ward on postoperative day 3 and was discharged from the hospital on the postoperative 7th day. Benign multinodular hyperplasia was reported on the histopathological report. Patient was included in routine follow-up.

DISCUSSION

In the present case tracheal destruction due to compression of the giant goiter was found in agreement with previous reports. Emergency thyroidectomy was performed after awake intubation since it is a common surgical option for the treatment of giant goiter causing severe airway obstruction.

CONCLUSION

Respiratory failure due to giant nodular goiter is a life-threatening situation and should be treated immediately by performing awake endotracheal intubation following emergency total thyroidectomy.  相似文献   
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BackgroundThis study aims to show the corrective effect of verbascoside on histomorphological and biochemical differences in the colon mucosa of rats in which colon ischemia–reperfusion (I/R) injury was induced.Methods: Fifty Sprague Dawley male rats were divided into 5 groups, of control, sham, ischemia (I), I/R, and I/R+verbascoside.Ischemia and reperfusion were applied to the suitable groups for 30 minutes and 120 minutes respectively, and 10 mg/kg verbascoside was administered intraperitoneally. Histomorphological assessment was done in the colon tissues obtained, and the goblet cells were assessed using the Alcian blue method. Proliferating cell nuclear antigen (PCNA), TUNEL, and hypoxia-induced factor 1 (HIF-1α) assays were used to assess oxidative stress with the immunohistochemical method. Malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), and total thiol (TT) levels were checked, for a biochemical analysis of oxidative stress.Results: Compared with the I/R group, histomorphological differences were seen to be corrected in colon epithelium in the I/R+verbascoside group. The goblet cell number increased and cell proliferation was increased, as seen with the PCNA assay; and apoptosis was decreased, as seen with the TUNEL assay. HIF-1α expression also decreased in the drug group. In the drug group, SOD, GSH-Px, TAS, and TT levels increased, but TOS, OSI, and MDA levels decreased.Conclusion: It was seen that verbascoside had a corrective effect on histomorphological and biochemical differences caused by I/R injury.  相似文献   
8.
ObjectivePublications on histopathology of human temporal bones with cytomegalovirus (CMV) infection are limited. We aim to determine histopathology of the inner ears and the middle ears in human temporal bones with congenital and acquired CMV infections.MethodsTemporal bones from 2 infants with congenital and 2 adults with acquired CMV infection were evaluated by light microscopy.ResultsTwo infants with congenital CMV infection showed striking pathological changes in the inner ear. There was a hypervascularization of the stria vascularis in the cochlea of the first infant, but no obvious loss of outer and inner hair cells was seen in the organ of Corti. However, cytomegalic cells and a loss of outer hair cells were found in the cochlea of the second infant. The vestibular organs of both infants showed cytomegalic cells, mostly located on dark cells. There was a loss of type I and type II hair cells in the macula of the saccule and utricle. Loss of hair cells and degeneration of nerve fibers was also seen in the semicircular canals. Both infants with congenital infection showed abundant inflammatory cells and fibrous structures in the middle ear cavity. No evidence of cytomegalic cells and hair cell loss was found in the cochlea or vestibular labyrinth in acquired CMV infection.ConclusionsIn two infants with congenital CMV infection, the cochlea, vestibule, and middle ear were highly affected. Temporal bones of adult donors with acquired viral infection showed histological findings similar to donors of the same age without ear disease.  相似文献   
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Viral hepatitis B, post-hepatitic cirrhosis and hepatocellular carcinoma (HCC) is the classical sequence of events in hepatitis B virus (HBV) infected children and serum Alpha-fetoprotein (AFP) and ultrasound (USG) screening is recommended during follow up. We present a 13-yr-old girl with cirrhosis related to chronic HBV infection with normal AFP level and a 4 cm mass appearance by USG. Contrast spiral evaluation computed tomography (CT) study demonstrated a single mass located at 8th segment of the liver. Pre-contrast CT and portal venous phase studies showed heterogeneous liver parenchyma without mass appearance. HCC was suspected based on strong arterial enhancement. Two mediastinal lymphadenopathies, 1 cm under the xyphoid and 2 cm above the pericardium, were detected by thorax CT. Mediastinal exploration was undertaken with living related liver transplant donor in a second operating room. She was transplanted with the right lobe of her ABO compatible mother after evaluation of the lymph nodes revealed reactive histology by frozen section. Histologic evaluation of the explant liver documented cirrhosis with a cirrhotic nodule without histologic malignant evidence. False negative results from screening methods are familiar in the literature; however false positivity of a contrast CT study is rare. The significance of screening methods is discussed.  相似文献   
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