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31.
Elbieta Haustein Aleksandra Kuryowicz-Cudowska Aneta uczkiewicz Sylwia Fudala-Ksiek Bartomiej Micha Cielik 《Materials》2022,15(4)
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
32.
Magdalena Mrz Magdalena Gajcka Katarzyna E. Przybyowicz Tomasz Sawicki Sylwia Lisieska-onierczyk ukasz Zielonka Maciej Tadeusz Gajcki 《Toxins》2022,14(2)
The aim of this study was to determine whether low doses of zearalenone (ZEN) influence the carry-over of ZEN and its metabolites to the bone marrow microenvironment and, consequently, haematological parameters. Pre-pubertal gilts (with a body weight of up to 14.5 kg) were exposed to daily ZEN doses of 5 μg/kg BW (group ZEN5, n = 15), 10 μg/kg BW (group ZEN10, n = 15), 15 μg/kg BW (group ZEN15, n = 15), or were administered a placebo (group C, n = 15) throughout the entire experiment. Bone marrow was sampled on three dates (exposure dates 7, 21, and 42—after slaughter) and blood for haematological analyses was sampled on 10 dates. Significant differences in the analysed haematological parameters (WBC White Blood Cells, MONO—Monocytes, NEUT—Neutrophils, LYMPH—Lymphocytes, LUC—Large Unstained Cells, RBC—Red Blood Cells, HGB—Haemoglobin, HCT—Haematocrit, MCH—Mean Corpuscular Volume, MCHC—Mean Corpuscular Haemoglobin Concentrations, PLT—Platelet Count and MPV—Mean Platelet Volume) were observed between groups. The results of the experiment suggest that exposure to low ZEN doses triggered compensatory and adaptive mechanisms, stimulated the local immune system, promoted eryptosis, intensified mycotoxin biotransformation processes in the liver, and produced negative correlations between mycotoxin concentrations and selected haematological parameters. 相似文献
33.
Matosiuk D Fidecka S Antkiewicz-Michaluk L Lipkowski J Dybala I Koziol AE 《European journal of medicinal chemistry》2002,37(9):761-772
Synthesis and pharmacological activity of 1,6-diaryl-5,7(1H)dioxo-2,3-dihydroimidazo-[1,2-a][1,3,5]triazines (C) are presented. The title compounds were obtained from 1-arylimidazolinurea derivatives in cyclization reaction with difunctional carbonyl reagents--phosgene (method I) or carbonyldiimidazole (CDI) (method II). Their molecular structures were confirmed by the X-ray analysis of 1-phenyl-6-(4-chlorophenyl)-5,7(1H)-dioxo-2,3-dihydroimidazo[1,2-a][1,3,5]triazine (C2) crystals. Compounds C exhibited significant depressive action on the central nervous system (CNS) of the laboratory animals, correlated with very low acute toxicity (LD(50) > 2000 mg kg(-1) i.p.), and showed antinociceptive activity in behavioural models. Reversion of this effect by small dose of naloxone (5 mg kg(-1)) can suggest opioid-like mechanism of antinociception produced by these and other carbonyl derivatives of 1-aryl-2-iminoimidazolidine. Additionally, an effect on the serotonin neurotransmission pathway was also observed. The receptor mechanism of activity for investigated compounds was confirmed only for the opioid mu receptor in binding affinity assay test. Same tests performed for the serotonin 5-HT(2) and benzodiazepine BZD receptors showed no affinity for tested compounds. The opioid-like and serotonergic activities are similar to these described earlier for chain carbonyl 1-aryl-2-iminoimidazolidine derivatives containing urea moiety, mainly due to similar chemical structure, although compounds C are not able to adopt any of the higher energy conformations of urea derivatives. Rigid location of aromatic ring (Ar') at N6, acting as a spacer blocking any direct access to the carbonyl groups (e.g. through the hydrogen bonding), could be responsible for lack of affinity toward 5-HT(2) expressed in the binding assay test. 相似文献
34.
Matosiuk D Fidecka S Antkiewicz-Michaluk L Dybala I Koziol AE 《European journal of medicinal chemistry》2002,37(10):845-853
Synthesis and pharmacological activity of 1-aryl-5,6(1H)dioxo-2,3-dihydroimidazo[1,2-a]imidazoles (D) are presented. The title compounds were obtained from 1-aryl-2-iminoimidazolidines (1) by cyclization reaction with oxalic acid derivatives-ethyl ester (2) or chloride (3). They were tested for pharmacological activity in animal and binding assay tests. With moderate acute toxicity (LD(50) approximately 200 mg kg(-1), i.p.), they exhibited significant analgesic and serotonergic activities as results of the 'writhing' and the 'hot plate' tests indicated, and reduced number of 'head twitch' episodes after 5-HTP (5-hydroxytryptophan) administration. Reversion of the antinociception produced in the 'writhing' test by small dose of naloxon (5 mg kg(-1)) can suggest an opioid-like mechanism of their analgesic activity. The probable receptor inhibition mechanism of their analgesic and serotonergic activity was confirmed in the binding assay tests (by radioligand displacement) toward the opioid mu and serotonin 5-HT(2) receptors. Additionally, they exhibited affinity toward the benzodiazepine (BZD) receptor as well, although in behavioral tests compounds did not produce any clear depressive effect on the central nervous system (CNS) of mice. Simple chemical structure of the title compounds, in comparison to other carbonyl derivatives of 1-aryl-2-iminoimidazolidine presented in this series of papers, underline very important role both of a hydrophobic moiety (aromatic ring) and polar groups (hydrogen-bond acceptors) in the serotonin receptor interaction. The co-existence of opioid-like, serotonergic and BZD receptor inhibition activity can be very interesting and can lead to creation of the novel group of antidepressants. 相似文献
35.
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37.
Fankhauser F Kwasniewska S Van der Zypen E 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》2004,218(2):77-95
Laser cyclophotocoagulation is an accepted method of cyclodestruction, such as cyclocryothermy and the application of cyclodiathermy, microwaves and ultrasound. These procedures may be considered as ultima ratios or 'last-resort interventions'. Also, in cases where surgery is not possible, cyclodestruction may be the initial intervention. Among other lasers, the Nd:YAG and diode lasers are the energy sources of choice. Contact and noncontact methods have about the same clinical efficiency and risk. While immediate complications are transitory, other, late complications, mentioned in the world literature, such as sympathetic ophthalmia, malignant glaucoma and retinal detachment, are more serious but are rare, and their causal relationship with the cyclodestructive procedure is doubtful. However, they still merit our attention. The ultrastructural mechanisms related to cyclocoagulation have been studied. The study of aqueous flow may improve our understanding of cyclophotocoagulation techniques. Cyclophotocoagulation is considered an important cornerstone in glaucoma therapy. The uncertainty of its effect is no greater than that of any other therapeutic measure in the treatment of glaucoma. 相似文献
38.
Fankhauser F Kwasniewska S 《Ophthalmologica. Journal international d'ophtalmologie. International journal of ophthalmology. Zeitschrift für Augenheilkunde》2003,217(1):1-16
The clinical effects of the Nd:YAG laser operating in both the photodisruptive (Q-switched) and thermal (free-running, cw) modes are discussed, and their clinical applications investigated. Moreover, the physical background of the working modes is explored. When working in the photodisruptive and fundamental (TEM(00)) modes, it is possible to carry out delicate clinical tasks with minimally invasive effects. When the laser is being used in the multimode regime, tasks that are highly resistant to photodisruptive laser radiation can be undertaken. In the thermal mode, photocoagulation can be performed. Nd:YAG laser light (1,064 nm) has high optical tissue penetration and good hemostatic properties, particularly when it is being operated in the frequency-doubled mode (KTP laser). 相似文献
39.
Sacha T Hochhaus A Hanfstein B Müller MC Rudzki Z Czopek J Wolska-Smoleń T Czekalska S Salamanchuk Z Jakóbczyk M Skotnicki AB 《Leukemia research》2003,27(12):1163-1166
Imatinib mesylate (STI571) is a major therapeutic advance for the management of chronic myeloid leukaemia (CML), however, a proportion of patients are refractory to it, particularly those in more advanced phases of CML. Different mechanisms of resistance to imatinib are suggested, including point mutations within ABL-kinase domains. A point mutation leading to substitution at the ATP binding site of ABL-kinase and insensitivity to imatinib was detected in our patient treated with imatinib, who progressed to blast crisis. Additionally, clonal evolution could lead to BCR–ABL-independent proliferation. Early detection of ABL-kinase mutation could predict the progression of CML treated with imatinib. 相似文献
40.
Olejek A Kozak-Darmas I Biniszkiewicz T Kellas-Sleczka S Sieroń A 《Ginekologia polska》2008,79(4):276-280
INTRODUCTION: Vulvar intraepithelial neoplasia may lead to vulvar cancer. Vulvar cancer is a rare (accounting for about 2,5-5% of all malignant neoplasms), female genital organs cancer. Photodynamic therapy is a new treatment for a wide variety of malignancies and premalignant dysplasias. We wanted to examine the effectiveness of photodynamic therapy (PDT) on vulvar intraepithelial neoplasia (VIN). DESIGN: The aim of the study was to analyze the effectiveness of photodynamic therapy (PDT) on vulvar intraepithelial neoplasia (VIN). MATERIAL AND METHODS: We have analyzed 20 women with VIN, who were treated in our center - Clinic of Vulvar Diseases. All these women had photodynamic diagnosis (PDD), photodynamic therapy followed (PDT), with 5% ALA applied to the entire vulva. CONCLUSIONS: We have noted the reduction of subjective complaints, but the histopathological improvement was observed in fewer degree. 相似文献