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31.
OBJECTIVE: The current study was designed to test the possible release and bioavailability of polycyclic aromatic hydrocarbons (PAHs) from a set of commercial carbon blacks (CBs) as well as the ability of these PAHs to form bulky DNA adducts. METHODS: In four commercial CBs (Printex 90, Sterling V, N330, Lampblack 101), leaching of PAH was examined through (1) release of parent PAHs in saline with or without surfactant, and (2) PAH adducts in lung epithelial cells (A549) or in rat lungs after exposure to two CBs (Printex 90, Sterling V) for 13 weeks (50 mg/m(3)). In vitro experiments were done with original and extracted particles, as well as organic extracts of CB in DMSO. As positive controls, B[a]P (0.03 microM) and a mixture of 16 PAHs (0.1 microM) were used. RESULTS: No leaching of PAHs was measured in saline or surfactant-containing saline. In vitro incubations with CB particles (30-300 microg/cm(2)) revealed no adduct spots except for Sterling V. However, the spot was not concentration dependent and remains unidentified. Lung DNA from rats after inhalation of Printex 90 or Sterling V showed no spots related to PAH-DNA adduct formation compared to sham-exposed rats. CONCLUSION: The results suggest that PAHs are very tightly bound to these CBs. Only using organic extracts or particles of low-surface Sterling V, with high PAH content, PAHs may become available to form PAH-DNA adducts. However, the in vitro conditions showing this effect will not be encountered in vivo and renders this mechanism in particle-induced lung cancer at in vivo exposures highly unlikely.  相似文献   
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33.
The number of fluorodeoxyglucose PET applications is increasing. In the process of reading fluorodeoxyglucose-PET scans, nuclear medicine physicians encounter a wide variety of normal findings, which must be recognized to determine the best management for patients. It is important to recognize and understand normal variants to avoid misinterpretation of more serious pathology. This article reviews different patterns of physiologic fluorodeoxyglucose uptake including changes with age.  相似文献   
34.
A study on the prevalence of accessory auricle anomaly in Turkey   总被引:4,自引:0,他引:4  
OBJECTIVE: Accessory auricular anomaly is a small elevation of skin containing a bar of elastic cartilage localized most commonly just anterior to the tragus or ascending crus of the helix. The anomaly may exist isolated or may be associated with other congenital anomalies of the first arch. The purpose in this study is to detect prevalence of accessory auricle in Turkey and find out whether it is associated with other craniofacial anomalies or hearing loss. METHODS: The study was performed on 850 children from the age of 7 to 9 during a screening program in primary schools. Complete otolaryngologic examination and acoustic reflectometry measurements were performed on all the children. Full physical examination, tympanometric and audiometric evaluation and EEG measurements were added to the cases with accessory auricle anomaly. RESULTS: Among 850 children examined, four had accessory auricle anomaly and prevalence of the anomaly was calculated as 0.47% (95% confidence interval (CI), 0.13-1.20%). Children were developmentally normal, and no other congenital craniofacial or systemic anomaly was detected in any of the cases. Further, tympanometric, audiometric evaluations and EEG tests were in normal limits. CONCLUSIONS: In this study, the prevalence rate of the condition was calculated as 0.47%. Although one study from China reported this prevalence as 0.22%, the difference between the reported prevalances was not statistically significant. Further, although external ear anomalies may present together with cranifacial anomalies and neurologic disorders like epilepsy, neuromotor retardation and EEG disorders, in our cases, mental and motor development was normal and epilepsy history or abnormal EEG patterns do not exist. On the other hand, no hearing loss was found to be associated with accessory auricles.  相似文献   
35.
A series of hypospadias repairs using the Mathieu and V-incision-sutured (MAVIS) technique, aiming to achieve a normal-looking,vertical, slit-like meatus in 32 patients was reviewed. A Mathieu procedure was performed in 26 patients as a primary repair and in 3 as a rescue operation. In another 3 patients who had severe proximal hypospadias with failed repair, techniques other than Mathieu's were used. Good cosmetic and functional results were achieved in all patients.There were no complications such as fistula or stricture formation. The MAVIS meatoplasty creates a natural-looking, slit-like glanular meatus in both distal and proximal hypospadias, even in complicated cases.  相似文献   
36.
Purpose We review our experience of treating intestinal rotation anomalies in infants and children in the 22-year period between 1978 and 2000.Methods The type of operation performed, postoperative complications, and mortality were compared in three age groups. Group 1 consisted of neonates 1 month old, Group 2 consisted of infants aged 1 year old, and Group 3 consisted of children aged 1 year old.Results There were 101 infants and children, with a female:male ratio of 2:1. Of the 101 patients, 72 (71%) were neonates, with a mean age of 11.8 days (range 1–28 days); 20 (19.8%) were under the age of 1 year, with a mean age of 6.7 months (range 1–12 months); and 9 (8.9%) were 1 year of age, with a mean age of 6 years (range 1–9 years). Eighty-five (84%) patients underwent emergency procedures. Ladds operation was performed in all patients, with various additional procedures. The most frequent postoperative complications were adhesive intestinal obstruction, stoma necrosis, evisceration, and short bowel syndrome. The mortality rate was 36% in Group 1, 20% in Group 2, and 0% in Group 3.Conclusions In this series surgery was usually performed as an emergency procedure, with higher morbidity and mortality in newborns than in older infants and children.  相似文献   
37.
Testicular atrophy is a sequela of inguinal hernioplasty. The purpose of this study was to evaluate the effects of Lichtenstein (LHR) and laparoscopic totally extraperitoneal (TEP) hernia repair techniques on testicular function and volume. This study is a randomized prospective clinical trial with the blind assessment of outcome. A total of 26 patients who underwent elective herniorrhaphy for groin hernia were included in the study. Each patient was randomly assigned into one of two groups: either TEP or LHR (n = 13 for each). Six of the patients had bilateral hernia (n = 3 for each group). Luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone levels, and testicular volume by Doppler ultrasonography were detected just before and 3 months after the operation. LH, FSH levels did not change, when compared preoperative and postoperatively in both groups. Testicular volume and testosterone levels were observed to be significantly decreased after TEP when compared with LHR while no significant preoperative changes were observed between those groups. This affected the testicular volume in normal limits. TEP or LHR could not affect LH, FSH, testosterone values, but TEP could lead a decreasing effect on volume of testis in normal limits.  相似文献   
38.
OBJECTIVE: Weight gain frequently occurs during treatment with clozapine. However, the pathophysiology of clozapine-induced weight gain remains unclear. The aim of this study was to investigate the influence of clozapine on hormones leptin and insulin in relation to body weight and composition measures to determine their contribution to clozapine-induced weight gain. METHOD: Data are reported on 19 patients with schizophrenia (11 women and 8 men) who completed 10 weeks of treatment with clozapine. Insulin levels, weight measurements, body mass index (BMI), and body composition measurements were evaluated at baseline and at the end of treatment. Leptin levels were assessed at baseline and after 4 and 10 weeks of treatment. Analysis of variance with repeated measures was used to evaluate changes in weight, body composition measures, leptin, and insulin. The Pearson correlations were used to assess the relationships between changes in hormone levels and weight along with body composition measurements. The correlations of change in Positive and Negative Syndrome Scale (PANSS) score with changes in hormone levels, weight gain and body composition measures were evaluated with Pearson correlations. RESULTS: Leptin and insulin levels did not show any significant alterations across time. The use of clozapine was associated with significant increases in BMI (F=19.8, P<.001), lean muscle mass (F=8.2, P=.01), and fat mass (F=15.4, P=.001), while total body fluid percentage (F=4.1, P=.05) significantly decreased. Improvement in PANSS scores was not correlated to change in leptin, insulin, weight, BMI, or body composition measurements. The change in leptin levels was correlated to change in body fat mass. CONCLUSION: The role of leptin in weight gain induced by clozapine might be a regulatory mechanism rather than being etiologic.  相似文献   
39.
The objectives of this study were to determine the tetanus vaccination status for pregnant women, and to examine the effects of various factors on tetanus toxoid (TT) vaccination coverage during pregnancy in reproductive-age women. Four-hundred and ninety-three postpartum women who had live births at a hospital in Ankara were interviewed and information was collected on the mothers' sociodemographic characteristics, TT vaccination history, and prenatal care during the pregnancy studied. The rates for no vaccination, one-dose vaccination, and two-dose vaccination were 53.3%, 18.9%, and 27.8%, respectively. The vaccinated women (with at least one dose) were significantly younger, of lower parity, and had attended more prenatal care visits than the unvaccinated women. Of the women who attended at least one prenatal care check-up, only about half were vaccinated. Significantly more rural women were vaccinated against tetanus than urban women. Current vaccination rates with TT during pregnancy were found to be well below universal levels. Turkey needs to launch effective mass media campaigns that target urban and suburban populations, and inform and motivate women to request vaccination against tetanus.  相似文献   
40.
The objective of this study was to determine the tetanus immunity status of pregnant women at the time of delivery according to tetanus toxoid (TT) vaccination coverage during their most pregnancy. The serum anti-tetanus antibody levels of 493 mothers who had live births at a hospital in Ankara were determined by enzyme-linked immunosorbent assay (ELISA). Protected women were defined as those with serum antibody levels 0.6 IU/ml. Overall, 69.0% of mothers had protective tetanus antibody titers at the time of delivery. The rates of protection for mothers who had received no vaccination, one TT dose, or two TT doses during pregnancy were 46.4, 93.5, and 95.6%, respectively. Vaccinating every pregnant woman with at least one dose of TT would be an affordable and effective way to protect against neonatal tetanus, and would be a step toward eliminating the deaths that continue to occur due to this preventable disease in Turkey.  相似文献   
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