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81.
Since elemental mercury is absorbed by dental professionals through direct skin contact or inhalation, the use of mercury in dental amalgam continues to be a controversial issue. In this study, the authors address the possible health risk of occupational exposure to mercury vapor in the dental office. The cytogenetic examination of leukocytes with alkaline comet assay and blood mercury levels with Atomic Absorption Spectrometer of dentists exposed to mercury vapor below 0.1mg/m(3) concentrations failed to find cytogenetic damage and related correlation. However, higher cytogenetic damage and blood mercury levels evaluated in controls from mercury intake by seafood consumption justifies additional study.  相似文献   
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Non-dipper hypertension is associated with increased cardiovascular morbidity and mortality. We aimed to evaluate serum gamma-glutamyl transferase (GGT) level, which is accepted as a marker for oxidative stress and its relationship with inflammatory activity in patients with non-dipper hypertension. Age and sex matched 43 dipper hypertensive patients, 40 non-dipper patients, and 46 healthy subjects were included into the study. Serum GGT and C-reactive protein (CRP) levels were measured and compared between each of the groups. Serum GGT activity was higher in the non-dipper and the dipper hypertensive groups than in the control group (33.5 ± 11.8 and 28.1 ± 10.1 U/l, respectively, vs. 21.2 ± 6.5 U/l; p < 0.001). There was a statistically significant difference in serum GGT activity between the non-dippers and the dippers (p = 0.021). When compared with the control group, serum CRP levels were significantly increased in both the non-dipper and the dipper hypertensive groups (6.1 ± 2.6 and 5.4 ± 2.1 mg/l, respectively, vs. 2.8 ± 1.7 mg/L; p < 0.001). Increased CRP levels were higher in non-dippers than dippers (p = 0.046). A significant correlation was found between GGT and CRP measurements (r = 0.37, p = 0.002). Serum GGT levels, which are markers of the oxidative stress and CRP levels, are both increased in non-dipper hypertension. Increased GGT activity, found to be correlated with CRP levels, may be one of the reasons behind the non-dipper hypertension related cardiovascular complications.  相似文献   
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Ectopic adrenocortical tissues (EAT) are rare pathologies in children. They are frequently encountered in the inguinal region incidentally during surgical procedures but they are also classically known to be located from diaphragm to pelvis. EAT were investigated during inguinal procedures including inguinal hernia, hydrocele, hydrocele of cord and undescended testis (UDT) in 1,069 patients, 159 girls, 910 boys, from April 1997 until April 2006. All these nodules were confirmed to be adrenocortical tissues after histopathological examinations. Statistical analysis was done with Fisher's exact test. EAT were noted on the plexus pampiniformis external to processus vaginalis of 22 male patients (1.73%) during inguinal explorations. This figure was 1.63% for inguinal explorations of inguinal hernia, hydrocele and hydrocele of cord and 5.1% for UDT. This difference was statistically significant (P<0.0001). There were no EAT detected during inguinal exploration of female patients. EAT are uncommon pathologies seen during inguinoscrotal explorations. Incidence of EAT is significantly increased with UDT. This increase may be explained with the embryological events that take place during adrenal and gonadal development. The relatively low observation of EAT in girls may be due to the localization of gonads and association of EAT with gonadal position. Adrenal rests in inguinal region may suggest an association with descent of gonads.  相似文献   
86.
Public attitudes toward organ donation: A survey in a Turkish community   总被引:1,自引:0,他引:1  
Abstract. A survey of public attitudes toward organ donation and transplantation was conducted in a Turkish community. The 1030 subjects were chosen using a random, stratified method. Some 50.5% of those interviewed were willing to donate their organs while 33.7% refused and 15.8% were uncertain. A total of 53.6% said they would consent to donate a deceased relative's organs. Reasons for refusal to donate organs were as follows: fear that their body would be cut into pieces (43.8%), religious beliefs (26.2%), no reason (23.1%) and the belief that they would need their body and organs for their second life (6.9%). Attitudes toward organ donation were clearly related to level of education, age, sex, and socioeconomic status.  相似文献   
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Occupational exposure and sniffing of toluene-based organic solvents is an important public health problem. In this study, we have investigated the effects of paint thinner inhalation on testosterone synthesis and secretion in the male rat. A control group inhaled normal air ventilation. The remaining animals were divided into three groups and exposed to paint thinner in a glassy cage for 15 and 30 days (2 h/day). A group of rats was allowed to recover for 15 days after 30 days of exposure. Toluene concentration (the largest constituent in thinner, 66%) was set at 1500 ppm in the inhaled air. At the end, all animals were decapitated and blood samples obtained. Testes and seminal vesicles were removed and weighed out. Serum total testosterone levels were determined by chemiluminescence enzyme immunoassay. Testicular tissue specimens were processed for semi-quantitative evaluation of immunohistochemical testosterone staining and light microscopy. Intensity of immunostaining was evaluated on a scale between 0 (no staining), 1 (minimal), 2 (mild), 3 (moderate) and 4 (strong staining). Serum testosterone levels (ng/ml) were decreased by 15-day (3.31 ± 0.61) and 30-day (1.17 ± 0.54, p < 0.02) thinner exposure compared to the controls (3.91 ± 1.03). Another group of rats exposed to thinner for 30 days and then allowed to recover for a period of 15 days had significantly elevated levels of testosterone values (3.77 ± 1.1; p < 0.05). Immunohistochemical testosterone staining of the cytoplasm of Leydig cells was moderate (3+) and mild (2+) in 15 and 30 days thinner inhalation groups, respectively. Strong staining (4+) was restored following the recovery period. Testicular weight was significantly reduced in all test groups compared to the control values (p < 0.01). Diameters of seminiferous tubules were significantly decreased in the solvent exposed groups with enlarged connective tissue. The present findings suggest that paint thinner inhalation inhibits testosterone synthesis and secretion by a direct action on the Leydig cells in a reversible manner.  相似文献   
90.
Kirdak T  Saraydaroglu O  Duran C  Yerci O  Korun N 《Tumori》2006,92(5):444-448
Insular carcinoma of the thyroid is situated morphologically and biologically in an intermediate position between the well-differentiated and undifferentiated tumors and presents a variable clinical course in a widely heterogeneous spectrum. The present cancer staging system (TNM) for thyroid cancer considers differentiated and undifferentiated tumors while ignoring this intermediate type, which is also called poorly differentiated tumor. In addition to the limited data on this rare disease, some poorly differentiated thyroid tumors contain differentiated cancer areas at various rates. These factors may cause difficulties in estimating disease aggressiveness and prognosis. To solve this problem, various microscopic and immunohistochemical parameters can be assessed. In this paper we describe 3 patients affected by thyroid carcinoma with an insular component, who presented different clinical pictures. When these cases were examined, the TNM system failed in stage grouping for poorly differentiated thyroid tumors. Case 1 and case 2 had similar clinical stages according to the TNM staging system for differentiated tumors, but had different prognoses. Case 3, with more limited disease, had the highest rate of poorly differentiated areas but the lowest Ki-67 proliferation index. In conclusion, it is difficult to make claims about the clinical behavior and prognosis of thyroid carcinoma with an insular component based on the 3 cases reported in this study, but it can be speculated that there is a gap in the TNM system with regard to the staging of insular thyroid carcinoma. In this situation the assessment of microscopic and immunohistochemical features of the tumor may help to predict disease aggressiveness and patient risk. However, it is clear that there is a need for large-scale studies evaluating the prognostic importance of histopathological and immunohistochemical features in determining risk groups.  相似文献   
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