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991.
Large areas of formerly oak-dominated woodlands are currently managed for timber products, and if they are used in a conservation-oriented way, they are often abandoned and left to become wilderness. We focused on the situation when an oak woodland is still partly managed as an ancient game park and partly abandoned as a nature conservation amendment. We studied this effect using a multi-taxa approach with lichens, fungi and beetles and investigated their response to the changing patterns in canopy openness, dead wood distribution and host tree conditions. The study was done in the Hradec Králové region of the Czech Republic. We found that the maintenance of canopy openness, as determined by management, was the primary driver influencing species composition. Canopy closure led to homogenization of the beetle and lichen communities and the loss of species. Fungi were mainly driven by the amount of dead wood, and abandonment favored their species richness. The creation of a new wilderness was only profitable for fungi, and the maintenance of canopy openness was an important driver for most of the studied taxa (i.e., biodiversity maintenance). Canopy openness and the presence of veteran trees could be used as an indicator of a management history that helps conserve biodiversity. Appropriate conditions for all taxa studied could be fulfilled using wood pasturing or game keeping in combination with dead tree retention.  相似文献   
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To better understand insect evolution, fossils – mainly known by their wings – must be used as terminals in phylogenetic analyses. Such analyses are, however, rarely performed because of a lack of consensus on the homology of venation in insects. Researchers do not agree with the current concept on the exact number and identity of the main veins. Here, we confirm the presence, which has been in question since the early 20th century, of an independent main postcubital vein (PCu vein) between the cubital and anal veins (29 fossil and extant examined orders; > 85% of observed insects). The PCu vein corresponds to the so-called vein 1A or first anal vein. It is easily identified by the unique shape of its bulla. It may have several branches and be partially fused with the cubital and anal veins. Once the PCu vein was identified, we reconsidered as an example the particular case of the Phasmatodea, showing that extant stick insects have a unique venation among insects, with a reduced median vein and a simple cubital vein adjacent or fused to the PCu vein. This study is a new approach towards resolving wing vein homology issues, crucial for future large-scale phylogenetic analyses in insects combining extant and extinct taxa.  相似文献   
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Epidemiologic studies following the Czernobyl accident were performed in region Kraków, including Kraków, Nowy Sacz and Kielce district. 1426 males and 2495 females were selected according to the random sample on the whole population of Kraków and Nowy Sacz, as well as in some selected areas in Swietokrzyski Mountains, and in Kielcecity. The aim of the study was to assess the results of the prophylaxis with Kalium iodine after the radiation and the incidence of the goiter in the population. It was stated, that 19.2% of the population in Kraków district, 16.9% in Nowy Sacz and 20% in Kielce received the prophylactic dosis of K.J. 80% took mainly the Lugol solution, between May, the 1st and 5th, 1986. Among 18 of person showing side effects like gastrointestinal disturbances, 16 were of female sex. Goiter incidence according to WHO classification was 50.7%, 67.3% and 49.9% in Kraków, Nowy Sacz and Kielce respectively. The difference between the incidence of goiter in males and females was 1:3. In women it was rather Ist and IInd degree of goiter, in men OB and Ist. Nodules of thyroid gland in the rural region of Kraków, Nowy Sacz and Kielce were seen in women in 10.8%, 1.7%, add 12.3% consecutively. Hormonal studies i.e T3, T4, TSH serum concentration showed normal results in all groups studied. TSH concentration was the highest in the group OB. The microsomal and antithyroglobulin antibodies level was the same independently on the prophylactic dosis of Lugol solution. The high incidence of thyroid diseases not related to the accident was observed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Thiosemicarbazones (TSCs) are an interesting class of ligands that show a diverse range of biological activity, including anti-fungal, anti-viral and anti-cancer effects. Our previous studies have demonstrated the potent in vivo anti-tumor activity of novel TSCs and their ability to overcome resistance to clinically used chemotherapeutics. In the current study, 35 novel TSCs of 6 different classes were designed using a combination of retro-fragments that appear in other TSCs. Additionally, di-substitution at the terminal N4 atom, which was previously identified to be critical for potent anti-cancer activity, was preserved through the incorporation of an N4-based piperazine or morpholine ring. The anti-proliferative activity of the novel TSCs were examined in a variety of cancer and normal cell-types. In particular, compounds 1d and 3c demonstrated the greatest promise as anti-cancer agents with potent and selective anti-proliferative activity. Structure-activity relationship studies revealed that the chelators that utilized “soft” donor atoms, such as nitrogen and sulfur, resulted in potent anti-cancer activity. Indeed, the N,N,S donor atom set was crucial for the formation of redox active iron complexes that were able to mediate the oxidation of ascorbate. This further highlights the important role of reactive oxygen species generation in mediating potent anti-cancer activity. Significantly, this study identified the potent and selective anti-cancer activity of 1d and 3c that warrants further examination.  相似文献   
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