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The problem of poverty leads to increased use of both legal and illegal drugs. Tobacco and alcohol are legal drugs that cause particular concern. Both drugs are widely abused in Germany by people attempting to escape their everyday problems. For decades it has been known that tobacco and alcohol use are more prevalent in lower socio-economic groups of society (those with low educational achievement, compared with people with further or higher education qualifications). Tobacco and alcohol use is particularly high among the unemployed, either temporarily or long-term, as well as people living alone. Children and women are more concerned about smoking than men. Female loneliness, often accompanied by the appearance of depressive reactions or of depression, increases the likelihood of cigarette smoking. Poor people spend up to 20% of their income on tobacco. In many industrialized countries, the age of onset of smoking is becoming younger and younger, increasing the risk of development of avoidable tobacco-related illnesses at an earlier age. This means that young smokers who develop chronic tobacco-related illnesses will require medical care over many years, increasing the cost of treating tobacco-related disease. Within the next few years, effective prevention programs against smoking must be developed, particularly for the lower socio-economic populations, in order to stop the cost of healthcare systems spiraling over the coming decades.  相似文献   
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In this study, we investigated the role for ancestral functional variation that may be selected upon to generate protein functional shifts using ancestral protein resurrection, statistical tests for positive selection, forward and reverse evolutionary genetics, and enzyme functional assays. Data are presented for three instances of protein functional change in the salicylic acid/benzoic acid/theobromine (SABATH) lineage of plant secondary metabolite-producing enzymes. In each case, we demonstrate that ancestral nonpreferred activities were improved upon in a daughter enzyme after gene duplication, and that these functional shifts were likely coincident with positive selection. Both forward and reverse mutagenesis studies validate the impact of one or a few sites toward increasing activity with ancestrally nonpreferred substrates. In one case, we document the occurrence of an evolutionary reversal of an active site residue that reversed enzyme properties. Furthermore, these studies show that functionally important amino acid replacements result in substrate discrimination as reflected in evolutionary changes in the specificity constant (k(cat)/K(M)) for competing substrates, even though adaptive substitutions may affect K(M) and k(cat) separately. In total, these results indicate that nonpreferred, or even latent, ancestral protein activities may be coopted at later times to become the primary or preferred protein activities.  相似文献   
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The amount of fly ash from the incineration of sewage sludge is increasing all over the world, and its utilization is becoming a serious environmental problem. In the study, a type of sewage sludge ash (SSA) collected directly from the municipal sewage treatment plant was used. Five levels of cement replacement (2.5%, 5%, 7.5%, 10% and 20%) and unchanged water-to-binder (w/b) ratio (0.55) were used. The purpose of the study was to evaluate the effect of sewage sludge ash (SSA) on the hydration heat process of cement mortars. The heat of the hydration of cement mortars was monitored by the isothermal calorimetric method for 7 days at 23 °C. The analysis of chemical composition and particle size distribution was performed on the tested material. The tests carried out have shown that SSA particles have irregular grain morphology and, taking into account the chemical composition consists mainly of oxides such as CaO, P2O5, SiO2 and Al2O3. The concentration of these compounds affects the hydration process of cement mortars doped with SSA. In turn, the content of selected heavy metals in the tested ash should not pose a threat to the environment. Calorimetric studies proved that the hydration process is influenced by the presence of SSA in cement mortars. The studies showed that the rate of heat generation decreased (especially in the initial setting period) with the increasing replacement of cement by SSA, which also reduced the amount of total heat compared to the control cement mortar. With increasing mass of the replacement of cement with SSA up to 20%, the 7-day compressive strength of the mortar samples decreases.  相似文献   
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The rarely occurring multiple lentigines (LEOPARD) syndrome represents a complex of skin, heart, skeleton and other malformations and is described in a 36-year-old male and his 9-year-old daughter. With the occurrence of multiple lentigines, the diagnostic search for further malformations should always be undertaken. Its differential diagnosis and its pathogenetic and clinical aspects are discussed in this paper.  相似文献   
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The causal treatment of type I allergies by specific immunotherapy (SIT) is absolutely essential to counter the transformation of rhinitis into bronchial asthma. There are therapy allergens available for this purpose as finished drugs (with marketing authorization and subject to official batch testing) or as named patient products (NPP). Sixty to eighty percent of all preparations for SIT are compounded as NPP for a specific patient by his physician. Because of the enormous number of potential allergens, SIT also requires NPP, as the batchwise production of finished drugs would not be practical for possibly very small groups of patients. However, NPP may become a source of error in treating allergic diseases due to the compilation of mixtures for therapy being attributed to an inadequate anamnesis obtained through physicians without allergological experience, the compilation of mixtures of non cross-reacting allergens that may negatively influence the stability and efficacy of such a mixture, up to total ineffectiveness by proteolytic degradation, and the failure to reach the concentration essential for a clinical effect of each single allergen in a mixture. All these factors can only be controlled by intensive training of practising allergists and their cooperation with responsible acting manufacturers, since up till now efforts to subject NPP to binding regulations, comparable to those existing for preparations with marketing authorization, have failed.  相似文献   
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