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11.
In the atmosphere of Edirne 12 691 pollen grains belonging to 42 taxa were identified by using of Durham sampler in 2000 and 2001. A total of 6 189 pollen grains per cm2 were recorded in 2000 and a total of 6 502 pollen grains per cm2 in 2001. Total pollen grains consisted of 71.81% grains from arboreal plants, 25.88% grains from non-arboreal plants and 2.31% unidentified pollen grains. Pollen from the following taxa were also found to be prevalent in the atmosphere of Edirne: Gramineae, Pinus sp., Quercus sp.,Cupressaceae/Taxaceae, Platanus sp., Salix sp., Morus sp., Populus sp., Carpinus sp., Juglans sp.,Chenopodiaceae/Amaranthaceae, Fraxinus sp., Fagus sp., Ulmus sp., Ailanthus sp., Alnus sp., Ostrya sp.,Helianthus sp. The season of maximum pollen fall was from April to June, with a prevalence of arboreal pollen in the first month, and of pollen from non-arboreal plants in the last months of the year.  相似文献   
12.

Background

In the management of malignant pleural mesothelioma, radiotherapy has been used for the purpose of prophylaxis to reduce the incidence of recurrence at surgical insertion sites or palliate the symptoms.

Aim

The purpose of the study was to evaluate the techniques and effectiveness of radiotherapy in malignant pleural mesothelioma.

Materials and methods

Forty-four (18 female, 26 male) patients diagnosed with malignant pleural mesothelioma were retrospectively evaluated. All patients had surgery or thoracoscopic biopsy for diagnosis, staging or treatment and all received palliative or prophylactic radiotherapy. Fifty-seven percent of the patients received chemotherapy.

Results

Prophylactic radiation was applied to 27 patients with 4–15 MeV electron energies. The median radiotherapy dose was 30 Gy with 3 Gy daily fraction dose. During treatment, 12 patients had grade 1 erythema according to the RTOG scale. In 3 (12%) patients, a local failure at treatment field was observed. Palliative radiotherapy was applied to 17 patients for pain palliation. The median radiation dose was 40 Gy with 2 Gy daily fraction dose by using 6–18 MV photon and/or 4–12 MeV electron energies. Two patients had grade 1 erythema and one patient had grade 2 odynophagy according to the RTOG scale. For 10 (59%) patients, palliation of chest pain was delivered. No late toxicity was observed for all cases.

Conclusion

Our experience showed that prophylactic and palliative radiotherapy are effective and safe therapy modalities in malignant pleural mesothelioma in preventing seeding metastasis at intervention sites or relieving pain. Prospective randomized studies are still needed to determine the benefits of radiotherapy application and to indicate optimum dose schemes.  相似文献   
13.
The use of carbon-based conductive materials has been shown to lead to an increase in biogas and methane yields during anaerobic digestion (AD). The effect of these additives on AD using synthetic substrates has been extensively studied, yet their significance for wastewater sludge digestion has not been adequately investigated. Therefore, the aim of this research was to optimize the concentration of petroleum coke (PC) that is a waste by-product of oil refineries, for the anaerobic digestion of wastewater sludge and investigation of phosphate removal in the AD process in the mesophilic temperature range. According to the results of the experiments, supplementing reactors with PC could significantly improve biogas and methane production. Supplementation of reactors with 1.5 g/L PC led to 23.40 ± 0.26% and 42.55 ± 3.97% increase in biogas production and methane generation, respectively. Moreover, the average volatile solids (VS), phosphate, and chemical oxygen demand (COD) removals were 43.43 ± 0.73, 46.74 ± 0.77%, and 60.40 ± 0.38%, respectively.  相似文献   
14.
Recently, many studies have been carried out in relation to 900 MHz radiofrequency radiation (RF) emitted from a mobile phone on the brain. However, there is little data concerning possible mechanisms between long-term exposure of RF radiation and biomolecules in brain. Therefore, we aimed to investigate long-term effects of 900 MHz radiofrequency radiation on beta amyloid protein, protein carbonyl, and malondialdehyde in the rat brain. The study was carried out on 17 Wistar Albino adult male rats. The rat heads in a carousel were exposed to 900 MHz radiofrequency radiation emitted from a generator, simulating mobile phones. For the study group (n: 10), rats were exposed to the radiation 2 h per day (7 days a week) for 10 months. For the sham group (n: 7), rats were placed into the carousel and the same procedure was applied except that the generator was turned off. In this study, rats were euthanized after 10 months of exposure and their brains were removed. Beta amyloid protein, protein carbonyl, and malondialdehyde levels were found to be higher in the brain of rats exposed to 900 MHz radiofrequency radiation. However, only the increase of protein carbonyl in the brain of rats exposed to 900 MHz radiofrequency radiation was found to be statistically significant (p<0.001). In conclusion, 900 MHz radiation emitted from mobile/cellular phones can be an agent to alter some biomolecules such as protein. However, further studies are necessary.  相似文献   
15.
16.
The high-affinity sulfonylurea receptor (SUR1) gene regulates insulin secretion and may play a role in type 2 diabetes. A silent variant in exon 31 of SUR1 (AGG→AGA) was detected by single-strand conformational polymorphism and genotypes were determined for 396 Mexican American subjects (289 non-diabetic). The normal and mutant alleles were designated G and A, respectively. Among non-diabetics, those with the AA genotype had higher fasting insulin values than those with the AG and GG genotypes (113.4 pmol/l for AA vs 82.8 pmol/l for AG/GG, P=0.043). Similar results were observed for 2-h insulin (849.6 pmοl/l for AA vs 498.6 pmol/l for AG/GG, P=0.0003) and for the proinsulin to specific insulin ratio (0.068 for AA vs 0.056 for AG/GG, P=0.030). Specific insulin levels also differed significantly across the three genotypic classes (P=0.021). No differences in fasting glucose, body mass index, or waist circumference according to genotype were noted. Two-hour glucose was modestly higher in individuals with the AA genotype. Since we have previously reported linkage between SUR1 and hyperglycemia, the present association between a SUR1 variant and hyperinsulinemia in normal individuals from a high diabetes risk ethnic group raises the possibility of primary insulin hypersecretion as an antecedent of type 2 diabetes in at least some individuals from this population. Received: 3 April 1998 / Accepted: 5 June 1998  相似文献   
17.
Telomeres are specialized DNA–protein complexes found at the tips of linear chromosomes. In this study, we investigated the effects of oxidative stress on telomeric length distribution of proliferating vascular smooth muscle cells following balloon injury in single or combined treatment of rabbits with either buthionine sulfoximine or taurine. Exposure to oxidative stress increased the balloon injury whereas taurine treatment significantly diminished l-buthionine-sulfoximine-related intimal hyperplasia. Our results also showed that both variables had a significant influence on mean telomeric length distribution.  相似文献   
18.
We report a case of a 69-year-old male with non-ischemic cardiomyopathy, having drug- and antitachycardia pacing-refractory ventricular tachycardia resulted in multiple ICD shocks. The sustained and intractable ventricular arrhythmia was mapped and ablated with the aid of the three-dimensional electroanatomic mapping system, initially performed but unsuccessful from the endocardial site then performed successfully from the epicardial site via the coronary sinus.  相似文献   
19.
Effects of iloprost on visual evoked potentials and oxidant/antioxidant status were evaluated after bilateral carotid artery occlusion. There were three experimental groups; Sham (S) group (n=10), bilateral common carotid artery occluded (BCCAO) group (n=10) and after bilateral common carotid artery occlusion, iloprost-treated (BCCAOI) group (n=10). Iloprost was administered (0.5ng/kg/day) for 10 days by intraperitoneal injection. N(2) and P(2) latencies (millisecond) and N(2)-P(2) (microV) amplitudes were recorded 10 days after operation for evaluating VEPs. The rats were sacrificed by decapitation immediately after recording of VEPs. Malondialdehyte (MDA), glutathione (GSH), Cu-Zn superoxide dysmutase (SOD) were studied spectrophotometricly. After BCCAO, MDA levels were increased, GSH and Cu-Zn SOD levels were decreased significantly, and abnormal VEPs parameters were observed. Iloprost treatment after BCCAO decreased MDA and increased GSH levels significantly. Low Cu-Zn SOD levels and impaired VEPs remained after iloprost treatment. Iloprost treatment may protect the brain tissue from oxidative damage during cerebral hypoperfusion.  相似文献   
20.
Sister chromatid exchanges in lymphocytes of nuclear medicine physicians   总被引:2,自引:0,他引:2  
OBJECTIVE: The aim of this study was to assess whether occupational exposure to chronic, low doses of Iodine 131 (I-131) and Technetium 99m (Tc-99m) may lead to genotoxicity. Medical personnel occupied in nuclear medicine departments are occupationally exposed to low doses of I-131 and Tc-99m. The determination of the frequency of sister chromatid exchanges (SCEs) and of cells with a high frequency of SCEs (HFC) is considered to be a sensitive indicator for detecting genotoxic potential of mutagenic and carcinogenic agents. Therefore, we examined peripheral lymphocytes from nuclear medicine physicians for the presence of both SCE and HFC. METHODS: Sixteen exposed nuclear medicine physicians (non-smokers) were compared to 16 physicians (non-smokers) who had not been exposed to chemical or physical mutagens in their usual working environment at the same hospital. RESULTS: A statistically significant difference was found between SCE frequencies and HFC percentages measured in lymphocytes from the exposed and control groups. CONCLUSIONS: The present observation on the effect of chronic low doses of I-131 and Tc-99m indicates the possibility of genotoxic implications of this type of occupational exposure. Hence, the personnel who work in nuclear medicine departments should carefully apply the radiation protection procedures and should minimize, as low as possible, radiation exposure to avoid possible genotoxic effects.  相似文献   
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