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1.
In this paper, an antimycobacterial component of extracellular metabolites of a gut bacterium Raoultella ornithinolytica from D. veneta earthworms was isolated and its antimycobacterial action was tested using Mycobacterium smegmatis. After incubation with the complex obtained, formation of pores and furrows in cell walls was observed using microscopic techniques. The cells lost their shape, stuck together and formed clusters. Surface‐enhanced Raman spectroscopy analysis showed that, after incubation, the complex was attached to the cell walls of the Mycobacterium. Analyses of the component performed with Fourier transform infrared spectroscopy demonstrated high similarity to a bacteriocin nisin, but energy dispersive X‐ray spectroscopy analysis revealed differences in the elemental composition of this antimicrobial peptide. The component with antimycobacterial activity was identified using mass spectrometry techniques as a glycolipid–peptide complex. As it exhibits no cytotoxicity on normal human fibroblasts, the glycolipid–peptide complex appears to be a promising compound for investigations of its activity against pathogenic mycobacteria.  相似文献   
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Hypereosinophilic syndrome (HES) is defined as chronic, unexplained hypereosinophilia with organ involvement. A subset of HES patients presents an interstitial deletion in chromosome 4q12, which leads to the expression of an imatinib-responsive fusion gene, FIP1L1-PDGFRA. These patients are diagnosed as chronic eosinophilic leukaemia (CEL). We treated seven CEL and HES patients, six of which expressed FIP1L1-PDGFRA , with imatinib using initial daily doses ranging from 100 to 400 mg. In a remission maintenance phase, the patients were treated with imatinib once weekly. All imatinib-treated patients achieved a complete haematological remission (CHR), and five of the six patients with FIP1L1-PDGFRA expression exhibited molecular remission. The decreased imatinib doses were as follows: 200 mg/week in three patients, 100 mg/week in two patients and 100 mg/d in the remaining two patients. For remission maintenance, imatinib doses were set at 100 mg/week in five patients and 200 mg/week in two patients. At a median follow-up of 30 months all patients remained in CHR and FIP1L1-PDGFRA expression was undetectable in five of the six FIP1L1-PDGFRA -expressing patients. These data suggest that a single weekly dose of imatinib is sufficient to maintain remission in FIP1L1-PDGFRA - positive CEL patients.  相似文献   
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The aim of this study was to determine the possibility of using feathers of blue tit nestlings to assess the level of endogenous accumulation of lead. For this purpose we conducted an experiment with lead application to randomly chosen nestlings from eight randomly drawn broods. Five days after the exposure, feathers of lead-treated nestlings had significantly higher lead concentrations than control nestlings. This result suggests that feathers can be used as reliable non-destructive bioindicators to assess the level of heavy metals originating from contaminated food, which is of great significance for comparative studies on ecological consequences of pollution.  相似文献   
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The identification of a sub-endocardial infarction is of major interest in cardiology. This study evaluates the sensitivity of selected measures to the thickness of such an infarction. Synthetic ultrasonic data (long-axis view) of left ventricular models with inclusions were generated using Field II and meshes obtained from finite-element simulations, which also provided the reference for the estimates obtained from ultrasonic data. The displacements, the first and second component of the principal strain (ε1 and ε2), and several measures derived from these quantities were estimated. All estimates, except for the poorly estimated ε2, exhibited sensitivity to the presence and transmurality of the inclusion. The most sensitive was the gradient of the averaged transmural profiles of ε1, and ε1 averaged over the area corresponding to the transmural inclusion. The inflection point of the ε1 profile shifted toward the outer wall with increasing thickness of the non-transmural inclusion.  相似文献   
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Novel inhibitors of cholinesterases, especially butyrylcholinesterase (BuChE), were obtained by coupling melatonin–tacrine heterodimers via the carbamate bond. Compounds 14a‐i possessed potent cholinesterase inhibitory activity (with IC50 values as low as 1.18 nm for acetylcholinesterase (AChE) and 0.24 nm for butyrylcholinesterase (BuChE)). These heterodimers exhibit selectivity toward BuChE, being from 4‐ to 256‐fold more active toward BuChE than AChE, but still acting as better AChE inhibitors than tacrine 4 .  相似文献   
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The investigations of the influence of Fasciola hepatica invasion on the assorted parameters of milk quality were performed in cows. Mean protein content in the milk from infected animals ammounted 3.60% and was higher than in the milk from uninfected cows (3.30%). Similar tendency was observed in the case of the fat (5.08% and 3.91%) and lactose (4.36% and 4.34%). The count of somatic cells in milk from infected cows was lower than in milk from uninfected animals (356.07 and 1776.92). It can indicate immunosupressive activity of Fasciola hepatica on the host.  相似文献   
10.
The aim of the study was to determine the prevalence of Echinococcus multilocularis in red foxes (Vulpes vulpes) in Poland. Overall, 1,546 intestinal samples from 15 of the 16 provinces in Poland were examined by the sedimentation and counting technique (SCT). The mean prevalence of E. multilocularis in Poland was 16.5 % and was found in 14 of the 15 examined provinces. The mean intensity of infection was 2,807 tapeworms per intestine. Distinct differences in prevalence were observed between regions. In some provinces of eastern and southern Poland, the level of prevalence was 50.0 % (Warmińsko-Mazurskie), 47.2 % (Podkarpackie), 30.4 % (Podlaskie) and 28.6 % (Ma?opolskie), while in other provinces (west and south-west), only a few percent was found: 2.0 % (Dolno?l?skie), 2.5 % (Wielkopolskie) and 0.0 % (in Opolskie). The border between areas with higher and lower prevalence seems to coincide with a north–south line running through the middle of Poland, with prevalence from 17.5 to 50.0 % in the eastern half and from 0.0 to 11.8 % in the western half. The dynamic situation observed in the prevalence of this tapeworm indicated the necessity of continuing to monitor the situation concerning E. multilocularis in red foxes in Poland.  相似文献   
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