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21.
We examined gap junctional intercellular communication (GJIC) of primary human mesothelial cells and cell lines of asbestos-associated human pleural mesotheliomas, and the effect of asbestos and other mineral fibres on these cells. In homologous cultures, the GJIC capacity of six out of seven tumour cell lines was markedly less than for primary mesothelial cells. This defect in GJIC appeared not to be at the expression level of mRNA and protein of the gene encoding the 43 kDa gap junction protein. In heterologous cocultures of tumour cells and primary mesothelial cells, however, 80-90% of the tumour cell/normal cell contacts were functional. Exposure of primary mesothelial cells to TPA, a phorbol ester tumour promoter, resulted in marked inhibition of GJIC, being an action common to numerous tumour promoters. Such an effect though was not observed with the carcinogenic mesothelioma-inducing mineral fibres chrysotile and amosite, neither with glass wool. These results suggest that a permanent defect in GJIC capacity is a common feature of human mesothelioma cells, but how mineral fibres are involved in the process of mesotheliomagenesis is still unclear.  相似文献   
22.
Since it covers the lateral wall of the mastoid air system, the suprameatal triangle is of importance to otologic surgeons during mastoidectomy. Because of this clinical importance, topographic anatomy of the suprameatal spine and depression was studied on Anatolian skulls. In all, 363 male and 231 female skulls were studied. The most prevalent type of suprameatal spine resembled a crest and was found in both sexes on the right (77.6%) and left (80%) sides. The absence of a suprameatal depression was significantly higher in females (right 9.1%; left 8.7%) than in males (right 1.7%; left 2.5%). Suprameatal depressions were mostly shallow in female subjects, but were mostly observed in males to be at a medium depth or deep.  相似文献   
23.
The aim of this study was to determine the levels of Cu, Zn, Fe, Pb and Cd in various fruits (tomato, cherry, grape, strawberry) and vegetables (parsley, onion, lettuce, garlic, nettle, peppermint, rocket, spinach, dill, broad bean, chard, purslane, grapevine leaves) grown in Manisa region. Flame and Graphite Furnace Atomic absorption spectrometry was used to estimate and evaluate the levels of these metals. Detected levels ranged from 0.56 to 329.7, 0.01 to 5.67, 0.26 to 30.68, 0.001 to 0.97 and 0 to 0.06 μg/g for Fe, Cu, Zn, Pb and Cd, respectively. While the highest mean levels of Cu and Zn were detected in grapevine leaves, the lowest mean levels of Fe and Pb were detected in nettle. Cd was not detected in most of the fruits and vegetables studied. The estimated daily intakes of Cu, Zn, Fe, Pb and Cd through fruits and vegetables were found to be below the maximum tolerable levels recommended by FAO/WHO. The element concentrations of fruits and vegetables analyzed in this study were within safety baseline levels for human consumption.  相似文献   
24.
In the present study, a total of eight sourdough samples were collected from three different bakeries at two different times in Turkey. Also, laboratory-scale sourdough production was conducted by daily back-slopping for 7 days. Microbiological and chemical properties of the sourdoughs were investigated. Yeast species in the sourdoughs were identified by subjecting all presumptive yeast cultures to internal transcribed spacer region amplification of the 5.8S rRNA gene, restriction fragment length polymorphism analysis using Hae III, Hha I, and Hinf I endonucleases, and sequence analysis of the D1/D2 domain of the 26S rDNA gene. A total of seven profiles were determined according to the restriction fragments. Totally, 148 yeast isolates were identified at the species level (≥400 bp , 99% identity) as Saccharomyces cerevisiae (106), Kazachstania bulderi (11), Pichia fermentans (nine), Pichia membranifaciens (eight), Kazachstania servazzii (seven), Kazachstania unispora (four), and Hanseniaspora valbyensis (three). Although collected sourdoughs were produced without using baker's yeast, S. cerevisiae was the most frequently isolated yeast species. This can be related to the contamination of the bakery environment with commercial baker's yeast during the production of other bakery products. The pH and acidity levels of the collected sourdough samples ranged from 3.71 to 3.96 and 6.78 to 23.93 mL 0.1 N NaOH/10 g dough, respectively. Mean values of the content of maltose + sucrose, glucose, fructose, lactic acid, and acetic acid were 2.43, 1.57, 2.67, 7.30, and 1.40 g/kg, respectively. Due to the artisan and region-dependent handling of the sourdough, different biochemical patterns were observed among the collected samples.  相似文献   
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Assignment decisions of referees to football (soccer) games are highly debated in sports media. Referee assignments are typically done on a weekly basis as the league progresses. However, this practice ignores important workload constraints on referees. Moreover, referees' skill levels should also be considered in determining their assignments. In this article, we first give a mixed integer linear program formulation for the problem of simultaneously generating a game schedule and assigning main referees to games by incorporating specific rules in the Turkish league. We also approach this problem using a genetic algorithm (GA) because of the computational difficulties in solving the problem. In the GA solution pool, we suggest using templates for referee assignments that follow several referee‐related workload constraints. We explain how these templates can be obtained by solving a mixed integer linear model prior to running the GA. The usage of these templates for referee assignments is conceptually similar to using a basic match schedule for game scheduling such as the one used in the Turkish Football League. We use the Turkish Football League fixtures for 2010–2013 as a case study. Experiments with the GA using real‐world data show a rather modest performance in terms of computation time and objective function value. Our numerical results indicate that the problem is extremely hard to solve.  相似文献   
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28.

Aim

To evaluate changes in the coordinates of the line of sight (LoS) and higher order aberrations (HOAs) of eyes with keratoconus, following corneal cross-linking (CXL).

Methods

All patients (93 eyes) underwent detailed ophthalmologic examination and Pentacam HR measurements at baseline and at 3, 6, and 12 months after corneal CXL. LoS coordinates on the horizontal (x) and vertical (y) axes, vertical coma, vertical trefoil, spherical aberration, total root–mean square (RMS), and HOA-RMS values were recorded along with visual acuity and topographical parameters.

Results

LoS significantly shifted to the nasal region after corneal CXL in both right and left eyes (p = 0.003 and p = 0.01, respectively). Horizontal axis values of both eyes significantly shifted to the temporal region at postoperative 6th months compared to the baseline measurements (p = 0.02 and p = 0.02, respectively) and remained the same between postoperative 6th months and 12th months (p = 1.00 and p = 0.97, respectively). Total-RMS, HOA-RMS, vertical coma, and spherical aberration values significantly improved after corneal CXL (p < 0.001, p = 0.02, p = 0.04, and p < 0.001, respectively). The improvements in HOAs were significant at postoperative 6th months compared to the baseline measurements (p = 0.003, p = 0.02, p < 0.001, and p = 0.003, respectively) while remained the same between postoperative 6th months and 12th months (p > 0.05 for all values). The changes in horizontal-axis coordinates in left eyes were significantly correlated with anterior elevation, anterior astigmatism, total-RMS and HOA-RMS changes (r2 = 0.20, p = 0.03; r2 = 0.35, p < 0.01; r2 = 0.50, p < 0.001 and r2 = 0.35, p = 0.004; respectively).

Conclusions

LoS significantly shifted to the nasal region and HOAs improved after corneal CXL and these changes stabilized 6th months after corneal CXL. It would be more better to perform refractive surgery in crosslinked corneas at least 6th months after corneal CXL.  相似文献   
29.
In this study, polyurethane-films loaded with diclofenac were used to analyze the drug release kinetics and mechanisms. For this purpose, the experimental procedures were developed under static and dynamic conditions with different initial drug loads of 10, 20, and 30%. In the dynamic condition, to better simulate the biological flow, drug release measurements were investigated at flow rates of 7.5 and 23.5 ml/s. These values indicate the flow rate of the internal carotid artery (ICA) for a normal state of a body and for a person during the exercise, respectively. The experimental data were analyzed and adjusted by Higuchi, Korsmeyer–Peppas, First-order, zero-order, and Peppas–Sahlin models in order to understand the mechanisms contributed. Finally, drug release mechanisms were specified by investigating the model correlation coefficients. Experimental results showed that increasing the flow rate and initial drug loads enhance drug liberation. In addition, the rate of release is more influenced by the drug dosage in the static state. The analysis revealed that diffusion, burst, and osmotic pressure are the principal mechanisms contributed. Moreover, Fickian type was the dominant mechanism at all duration of release. However, it was discovered using Peppas–Sahlin model that the contribution of the diffusion mechanism decreases with increasing flow rate and initial dosage. Furthermore, the tests at different drug dosages showed that the number of stages in medication release profile is independent of the flow rate and the medicine percentage. One can conclude that the drug release kinetic in static state is more influenced by drug dosage compared with dynamic state.  相似文献   
30.
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