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1.
A new series of 6, 7-dihydroxy-3-(methylphenyl) chromenones, including three new derivatives, i.e. 6,7-dihydroxy-3-(2-methylphenyl)-2H-chromen-2-one (OPC); 6,7-dihydroxy-3-(3-methylphenyl)-2H-chromen-2-one (MPC); 6,7-dihydroxy-3-(4-methylphenyl)-2H-chromen-2-one (PPC) and one previously described, namely 6,7-dihydroxy-3-phenyl-2H-chromen-2-one (DPC), were synthesized. These compounds were investigated as inhibitors of human carbonic anhydrase I (hCA-I) and human carbonic anhydrase II (hCA-II) which had been purified from human erythrocytes on an affinity gel comprised of L-tyrosine-sulfonamide-Sepharose 4B.  相似文献   
2.
Mara? powder is a kind of smokeless tobacco used in the south-eastern region of Turkey. The present study was carried out to assess possible DNA damage in exfoliated oral cells of Mara? powder users by analysing the frequencies of micronuclei (MN), which is a simple and reliable biomarker for genotoxic damage and to screen for the detection of site-specific differences in the frequencies of MN. The mean (±SD) MN frequency in the inner lip mucosa site was 1.27(±0.55) % for Mara? powder users and 0.88(±0.47) % for non-smoking control subjects (p < 0.05) and 0.82(±0.40) % for the buccal site of Mara? powder users (p < 0.01). There was no significant site-specific difference between the inner lip site and the buccal mucosa site 0.73(±0.43) % in the MN frequency of non-smoking control subjects (p > 0.05). There was no significant effect of daily consumption of Mara? powder, and duration of usage on MN frequencies. The present study suggests that the oral use of smokeless tobacco represents a genotoxic hazard and also that use of MN from a single site may be misleading as a marker of genotoxic exposure. Habitual use of Mara? powder should be taken into account and could be considered unsafe.  相似文献   
3.
Abstract:  Western corn rootworm (WCR), Diabrotica virgifera virgifera LeConte, larval damage in maize following soybean was observed in Croatia in 2003 along the edges and within soybean fields which bordered continuous maize fields in previous year. The explanation was that WCR adults moved from the continuous maize to the neighbouring soybean fields to lay eggs. This study was designed to measure how far WCR adults will enter into neighbouring fields to lay eggs. The WCR adult population was monitored in continuous maize fields in 2003 and 2005 by using Pherocon® AM non-baited yellow sticky traps in the middle and on the borders of the maize field and at different distances and directions into neighbouring fields planted by wheat and soybean. Larval presence and root damage ratings (Iowa State University 1–6 ) were recorded at different locations within the maize field in following years. Approximately, the same concentration of WCR adults was recorded along the edges of the maize fields as recorded in the centres of those fields. A significant number of WCR adults was recorded up to a distance of 50 m into neighbouring fields. Regression analysis showed medium negative correlation between distance from previous maize field and root damage in the following year. Findings indicate that WCR egg lying can reach approximately 20 m into fields neighbouring maize fields and that significant root damage caused by WCR larvae in first-year maize following soybean and wheat can happen up to a distance of 20 m into those fields. Most farmers's fields in Croatia are up to approximately 50 m wide. As an edge effect for WCR egg laying can reach approximately 20 m into fields neighbouring maize fields, our research results indicate that it is possible to see WCR larval damage in rotated fields without those WCR's being the variant form.  相似文献   
4.
Hind wing shape variation was examined in 686 adult Diabrotica virgifera virgifera collected from maize plants in Europe and the USA Corn Belt, using geometric morphometric techniques. Sexual dimorphism at an Intercontinental scale was assessed using canonical variates analysis, a multivariate statistical method used to find the shape characters that best distinguish among groups of specimens. Our results showed that each of the populations of D. v. virgifera investigated in this study showed high levels of sex based hind wing shape dimorphism. In particular a stronger and more obvious pattern of hind wing shape variation was found in the USA than in Europe. These results support previous studies on D. v. virgifera wing shape that show that female D. v. virgifera have more elongated wings than males. These differences raise the question of whether sexual dimorphism may be modulated by natural selection.  相似文献   
5.
Multiple myeloma (MM) is a neoplastic disorder characterized by monoclonal multiplying of plasma cells. Although radiation, environmental factors, viruses and other factors have been suggested as potential causes of the disease, the aetiopathogenesis of MM is still obscure. This clinical study was designed to investigate the role of reactive oxygen species (ROS) in the aetiopathogenesis of the disease and the possible relationships between treatment and ROS production. For this purpose, erythrocyte superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) activities as well as plasma nitric oxide (NO) and malondialdehyde (MDA) levels were measured in 14 MM patients newly diagnosed at stage III. The relationship between the above-mentioned parameters and vincristine-adriamycin-dexamethasone (VAD) therapy were also investigated in the same patients. All the enzyme activities and the parameters of oxidative stress were found to be significantly reduced after VAD therapy. These findings suggest that ROS may be involved in the aetiopathogenesis of MM. Further investigations with a larger cohort of MM patients are needed to provide definitive data about the role of ROS in MM and the alternative therapeutic approaches to MM.  相似文献   
6.
The proposed short synthesis involves two key steps: Oxidation of the isopropylidene derivative of the 3-fluoronucleoside possessing a free hydroxyl group in 2-position and acetylation of deprotected 3-fluoro-2-ketonucleoside which, after a beta-elimination reaction, gives the desired unsaturated ketonucleoside 5.  相似文献   
7.
Toluene is used widely, not only in industry, but also in households where toluene exposure and abuse can occur. To estimate the genotoxic risk of toluene exposure, DNA damage was determined in peripheral lymphocytes of 20 glue sniffers and 20 age-matched controls by use of the alkaline comet assay. Urinary hippuric acid and o-cresol excretion rates, which are used as a marker for toluene exposure, were also measured in sniffers and compared with historical control values. The increase in genetic damage in sniffers was statistically significant as compared to control subjects (P<0.0001). The mean values of the hippuric acid and o-cresol excretion rate for glue sniffers was 73- and 1582-fold higher, respectively, than in controls and confirms the putative exposure. Education of the general public and efforts to keep adolescents away from volatile solvent-based products, which may lead to a desire of sniffing in the future, would be advisable.  相似文献   
8.
Catechol and pyrogallol are allelochemicals which belong to phenolic compounds synthesized in plants. Their antimicrobial activities were investigated on three bacteria (Pseudomonas putida, Pseudomonas pyocyanea, Corynebacterium xerosis) and two fungi (Fusarium oxysporum, Penicillium italicum) phytopathogenic species as test organisms using the disc diffusion method. Both catechol and pyrogallol were found to have antibacterial effects on all the bacteria used in the study at 5 and 10 mM concentrations. Catechol has also been found to have an antifungal effect on the fungi used in the study, whereas no antifungal effects of pyrogallol were observed. The most sensitive species among the bacteria was P. putida which was inhibited by the allelochemicals even at 1 mM concentration.  相似文献   
9.
10.
The aim of this study was to determine the prevalence and sociodemographic correlates of consanguineous marriages in Turkey using data derived from the 2003 Turkey Demographic and Health Survey (TDHS-2003). Demographic surveys conducted in the last 40 years consistently show that Turkey is a country with a high level of consanguinity. In the latest demographic survey (TDHS-2003), a nationally representative sample of 8075 ever-married women, consanguineous marriages accounted for 22% of the total, which is equivalent to a mean coefficient of inbreeding (alpha) of 0.011. There are changing secular profiles in the rates of consanguinity in general and of the specific sub-types of cousin marriages in particular in Turkey. The prevalence of first cousin marriages among all consanguineous marriages presents a steady decline from one marriage cohort to the next. The changes observed over time may be attributable to several factors such as the increase in educational level of women, the nuclearization of the family system, the mobility from rural to urban settings, a better socioeconomic status of families, an increase in women's labour force participation in formal sectors, lower fertility rates resulting in a smaller number of cousins available for marriage, and an increased awareness of the effects of consanguineous unions on child health in cases where there is an inherited recessive disease in the family. Any attempts to discourage consanguinity at the population level appear to be inappropriate and undesirable, especially when the consanguineous union remains an integral part of the cultural and social life of Turkey. Nevertheless the WHO-recommended approach to minimizing the negative effects of consanguinity on child health should be followed, i.e. the identification of families with a high risk of a genetic disease and the provision of prospective genetic counselling.  相似文献   
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