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1.
Summary Familial occurrence of 1/21 translocation in connection with trisomy 21 was described. The possibilities of inheritance of further chromosome rearrangements arising during the gametogenesis of persons with this translocation were considered.  相似文献   
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ABSTRACT: INTRODUCTION: Valproic acid is a commonly used anti-epileptic drug. Hematological toxicities are among theoccasionally observed adverse effects of this medication. CASE PRESENTATION: We present the case of a 13-year-old Caucasian boy who demonstrated mild anemia 12months after the introduction of valproic acid therapy. A bone marrow biopsy revealedmaturation arrest of proerythroblasts. CONCLUSION: Prompt diagnosis and valproic acid discontinuation resulted in the patient's recovery.  相似文献   
4.
Dental composite materials contain polymers of methacrylates, which, due to mechanical abrasion and enzymatic action of saliva, may release their monomers into oral cavity and the pulp. Moreover, polymerization is always incomplete and leaves usually considerable fraction of free monomers. Mechanisms of the genotoxicity of methacrylate monomers have been rarely explored. As the polymerization of a monomer is catalyzed by a co-monomer, their combined action should be considered. In the present work, we investigated cytotoxic and genotoxic effects of urethane dimethacrylate (UDMA), often used as a monomer, at 1 mM, and triethylene glycol dimethacrylate (TEGDMA), a typical co-monomer, at 5 mM singly and in combination. Experiments were conducted on Chinese hamster ovary cells. Cell viability, apoptosis and cell cycle were assessed by flow cytometry, whereas DNA damage was evaluated by plasmid conformation test and comet assay. Both compounds decreased the viability of the cells, but did not induce strand breaks in an isolated plasmid DNA. However, both substances, either singly or in combination, damaged DNA in CHO cells as evaluated by comet assay. Both compounds induced apoptosis, but a combined action of them led to a decrease in the number of apoptotic cells. The combined action of UDMA and TEGDMA in the disturbance of cell cycle was lesser compared to the action of each compound individually. Individually, though UDMA and TEGDMA may induce cytotoxic and genotoxic, however, a combination of both does not produce a significant increase in these effects.  相似文献   
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Recent study has shown that a short photoperiod increases the accumulation and toxicity of cadmium (Cd) in the bank vole as compared to a long photoperiod. Since many of the effects of photoperiod on physiological processes in small mammals are transduced by the pineal gland and its hormone melatonin, in this study the effect of subchronic melatonin injection (7 mol/kg/day for 6 weeks) on the hepatic, renal and intestinal Cd accumulation in the bank voles raised under a long photoperiod and exposed to dietary Cd (0.9 mol/g) was examined. Simultaneously, histological examinations of the liver and kidneys, and analyses of metallothionein (MT) and lipid peroxidation were carried out. Melatonin co-treatment brought about a significant increase in the hepatic (61%), renal (79%) and intestinal (77%) Cd concentrations as compared to those in the Cd alone group. However, the concentrations of MT in the liver and kidneys of the Cd + melatonin co-treated bank voles did not differ from those in the Cd alone group. Also, histopathological changes in the liver (infiltration of leukocytes) and kidneys (glomerular swelling and a focal tubular cell degeneration) as well as an increase (2-fold) in the renal lipid peroxidation occurred only in animals from the Cd + melatonin group. These data indicate that (1) subchronic melatonin injection has similar effect on the tissue accumulation and toxicity of Cd to that produced by a short photoperiod and (2) the Cd-induced toxicity in the liver and kidneys of melatonin co-treated bank voles is probably due to increased Cd accumulation and decreased synthesis of MT.  相似文献   
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The aim of this study was to provide evidence for the expression of iNOS in the cells of inflammatory infiltrates around larvae in skeletal muscles of T. spiralis infected mice. The BALB/c mice (n = 8) divided into subgroups, received either aminoguanidine (AMG)--a specific iNOS inhibitor or albendazole (ALB)--an antiparasitic drug of choice in trichinellosis treatment. Control animals (n = 2 in each subgroup) were either uninfected and treated or uninfected and untreated. Frozen sections of hind leg muscles from mice sacrificed at various time intervals after infection were cut and subjected to immunohistochemistry, using monoclonal anti-iNOS antibody. The ALB-treated mice revealed stronger iNOS staining in the infiltrating cells around larvae than the infected and untreated animals. On the contrary, in the AMG-treated animals, the infiltrating cells did not show any specific iNOS reaction. These data confirm the specificity of iNOS staining in the cellular infiltrates around T. spiralis larvae and shed some light on the role of nitric oxide during ALB treatment in experimental trichinellosis.  相似文献   
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The genome sequences of two Escherichia coli O104:H4 strains derived from two different patients of the 2011 German E. coli outbreak were determined. The two analyzed strains were designated E. coli GOS1 and GOS2 (German outbreak strain). Both isolates comprise one chromosome of approximately 5.31 Mbp and two putative plasmids. Comparisons of the 5,217 (GOS1) and 5,224 (GOS2) predicted protein-encoding genes with various E. coli strains, and a multilocus sequence typing analysis revealed that the isolates were most similar to the entero-aggregative E. coli (EAEC) strain 55989. In addition, one of the putative plasmids of the outbreak strain is similar to pAA-type plasmids of EAEC strains, which contain aggregative adhesion fimbrial operons. The second putative plasmid harbors genes for extended-spectrum β-lactamases. This type of plasmid is widely distributed in pathogenic E. coli strains. A significant difference of the E. coli GOS1 and GOS2 genomes to those of EAEC strains is the presence of a prophage encoding the Shiga toxin, which is characteristic for enterohemorrhagic E. coli (EHEC) strains. The unique combination of genomic features of the German outbreak strain, containing characteristics from pathotypes EAEC and EHEC, suggested that it represents a new pathotype Entero-Aggregative-Haemorrhagic E scherichia c oli (EAHEC).  相似文献   
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Background  

Compared to the waveform or spectrum analysis of event-related potentials (ERPs), time-frequency representation (TFR) has the advantage of revealing the ERPs time and frequency domain information simultaneously. As the human brain could be modeled as a complicated nonlinear system, it is interesting from the view of psychological knowledge to study the performance of the nonlinear and linear time-frequency representation methods for ERP research. In this study Hilbert-Huang transformation (HHT) and Morlet wavelet transformation (MWT) were performed on mismatch negativity (MMN) of children. Participants were 102 children aged 8–16 years. MMN was elicited in a passive oddball paradigm with duration deviants. The stimuli consisted of an uninterrupted sound including two alternating 100 ms tones (600 and 800 Hz) with infrequent 50 ms or 30 ms 600 Hz deviant tones. In theory larger deviant should elicit larger MMN. This theoretical expectation is used as a criterion to test two TFR methods in this study. For statistical analysis MMN support to absence ratio (SAR) could be utilized to qualify TFR of MMN.  相似文献   
9.
Resistance to gentamicin, amikacin and kanamycin was screened in 270 clinical isolates of Enterobacteriaceae originated from April 19 to May 19, 2010 in a regular hospital in Warsaw, Poland. Most of the isolated bacteria were considered pathogenic. Nineteen isolates (7%) were simultaneously resistant to two or three of the tested aminoglycosides. MICs of the three aminoglycosides ranged form 128 to 1024 mcg/ml for six isolates. These isolates were suspected to produce 16S rRNA methylase. Genes encoding for three methylases reported in Europe: ArmA, RmtB and RmtC were searched by PCR. The armA gene was detected in all of the six isolates. This group encompassed Enterobacter cloacae (n=4), Klebsiella pneumoniae (n=1) and Proteus mirabilis (n=1). Five isolates of this group carried the bla(CAX-M) gene for CTX-M type ESBL. The remaining isolate E. cloacae DM0340 was ESBL negative and lacked bla(CRX-M) that may suggest an altered genetic environment of the armA gene in this isolate. Our results showed that 2.2% of the tested isolates produced 16S rRNA methylase ArmA. This finding may argue for a high incidence of ArmA producing Enterobacteriaceae in Poland when compared to reports from other European countries.  相似文献   
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