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61.
Facial laser Doppler flux (FLDF) consists of a mean value and complex oscillatory components called vasomotion. Vasomotion can be expressed as spectral amplitudes (SA) after the application of continuous wavelet transform. Vasomotion is influenced by cardiac activity (frequency interval I), respiration (interval II), intrinsic myogenic activity (interval III), neural mechanisms (interval IV) and endothelial mechanisms (intervals V and VI). Asymmetry of FLDF mean value was previously documented and hereby we present homogeneity assessment for FLDF vasomotion. Mean FLDF (p<0.001), total SA (p<0.001) and SA within frequency intervals I-VI were significantly higher in both cheeks compared to forehead. Total SA (p=0.009) and SA within frequency intervals I (p=0.041), II (p=0.005), III (p=0.009), IV (p=0.001) and V (p=0.036) were significantly higher in right than in left forehead. Human face is a heterogeneous microvascular region. Angiographic characteristics of deep horizontal sub-dermal plexus, endothelial and vascular smooth muscle cell heterogeneity, and plasticity of the microvasculature, autonomic asymmetry and facial neuropsychological asymmetry are possible causes of microvascular asymmetry. The origin and significance of microvascular imbalance need to be elucidated further. 相似文献
62.
The effects of general anesthesia on human skin microcirculation evaluated by wavelet transform 总被引:1,自引:0,他引:1
Landsverk SA Kvandal P Bernjak A Stefanovska A Kirkeboen KA 《Anesthesia and analgesia》2007,105(4):1012-9, table of contents
63.
Temporal-order judgements in the time range of some milliseconds were assessed by using two auditory tasks in 86 participants, aged from 20 to 69 years. Two stimulus presentation modes, binaural versus monaural, were compared. Elderly participants performed worse than the younger participants; however, different patterns of age-related declines were observed, depending on the presentation mode. In the monaural mode considerable deterioration was observed beyond 60 years of age, whereas in the binaural mode declines were found much earlier, from 40 years of age. Performance of the monaural task correlated with cognitive competences and provided important insight into neuronal timing mechanisms. In contrast, the binaural mode reflected a bias towards an integrated perception of sequential stimuli and was less related to cognitive resources. These findings provide evidence that age-related declines in human sequencing abilities involve, besides temporal mechanisms, also a mode-specific processing, presumably associated with different neuronal mechanisms. 相似文献
64.
Aneta Berner-Strzelczyk Justyna Kołodziejska Magdalena Piechota-Urbañska Mariusz Piechota Marian Mikołaj Zgoda 《Central European Journal of Medicine》2009,4(1):98-103
Dosing pediatric drugs available on pharmaceutical markets of analgesic, antifebrile and anti-inflammatory activity to children
up to 3 years of age is not precise and frequently causes problems. The aim of the study was to work out a pediatric teat
form of a drug with sodium ibuprofen and to determine the effect of sorbitol content on pharmaceutical availability of the
therapeutic agent. Three variants of tablets containing 50 mg of sodium ibuprofen differing in the percentage content of sorbitol
(from 37% - batch I to 79% - batch III) were produced. Quality tests of the produced forms of drugs (PPVI) were performed
and the tests of therapeutic agent pharmaceutical availability by spatula method and by a method with a teat. Tablets of all
batches had a smooth surface and same shape. The content of the therapeutic agent was within the limit of 95-105% of the declared
value. The highest value of Q coefficient in the release test by pharmacopeal method and the shortest disintegration time
(12 minutes) were obtained for tablets with 79% content of sorbitol. In conclusion, teat tablets with sodium ibuprofen of
the highest sorbitol content (79%) demonstrated the expected physicochemical parameters and high pharmaceutical availability. 相似文献
65.
Kilanowicz A Skrzypinska-Gawrysiak M Sapota A Galoch A Daragó A 《Ecotoxicology and environmental safety》2009,72(2):650-657
The aim of the study was to investigate the subacute toxicity of a polychlorinated naphthalene (PCN) mixture and its effect on cytochrome P-450 levels in rats. The animals were administered PCNs intragastrically in repeated daily doses of 1, 10, and 100 mg/kg. The animals were dissected after 7, 14, or 21 doses. Doses of 10 and 100 mg/kg induced a significant decrease in the body weight at all time points of the experiment compared with the control group. The exposure to PCNs increased both the level of total cytochrome P-450 and the activity of CYP 1A at the same time points. In the groups of rats given PCNs in doses of 10 and 100 mg/kg, an evident dose- and time-dependent increase in malondialdehyde (MDA) level was observed throughout the experiment. The correlation between the increased MDA and decreased glutathione (GSH) levels in the liver was also observed. 相似文献
66.
p38alpha is a stress-activated protein kinase that negatively regulates malignant transformation induced by oncogenic H-Ras, although the mechanisms involved are not fully understood. Here, we show that p38alpha is not a general inhibitor of oncogenic signaling, but that it specifically modulates transformation induced by oncogenes that produce reactive oxygen species (ROS). This inhibitory effect is due to the ROS-induced activation of p38alpha early in the process of transformation, which induces apoptosis and prevents the accumulation of ROS and their carcinogenic effects. Accordingly, highly tumorigenic cancer cell lines have developed a mechanism to uncouple p38alpha activation from ROS production. Our results indicate that oxidative stress sensing plays a key role in the inhibition of tumor initiation by p38alpha. 相似文献
67.
68.
Y-STR variation among Slavs: evidence for the Slavic homeland in the middle Dnieper basin 总被引:1,自引:0,他引:1
Rebała K Mikulich AI Tsybovsky IS Siváková D Dzupinková Z Szczerkowska-Dobosz A Szczerkowska Z 《Journal of human genetics》2007,52(5):406-414
A set of 18 Y-chromosomal microsatellite loci was analysed in 568 males from Poland, Slovakia and three regions of Belarus.
The results were compared to data available for 2,937 Y chromosome samples from 20 other Slavic populations. Lack of relationship
between linguistic, geographic and historical relations between Slavic populations and Y-short tandem repeat (STR) haplotype
distribution was observed. Two genetically distant groups of Slavic populations were revealed: one encompassing all Western-Slavic,
Eastern-Slavic, and two Southern-Slavic populations, and one encompassing all remaining Southern Slavs. An analysis of molecular
variance (AMOVA) based on Y-chromosomal STRs showed that the variation observed between the two population groups was 4.3%,
and was higher than the level of genetic variance among populations within the groups (1.2%). Homogeneity of northern Slavic
paternal lineages in Europe was shown to stretch from the Alps to the upper Volga and involve ethnicities speaking completely
different branches of Slavic languages. The central position of the population of Ukraine in the network of insignificant
AMOVA comparisons, and the lack of traces of significant contribution of ancient tribes inhabiting present-day Poland to the
gene pool of Eastern and Southern Slavs, support hypothesis placing the earliest known homeland of Slavs in the middle Dnieper
basin. 相似文献
69.
Interaction Between Val158Met Catechol‐O‐Methyltransferase Polymorphism and Social Cognitive Functioning in Schizophrenia: Pilot Study 下载免费PDF全文
Aneta Tylec Witold Jeleniewicz Ann Mortimer Małgorzata Bednarska‐Makaruk Katarzyna Kucharska 《Annals of human genetics》2017,81(6):267-275
The Val158Met catechol‐O‐methyltransferase (COMT) functional polymorphism may influence social cognitive functioning in patients with schizophrenia. Aspects of social cognition were evaluated with the Facial Expression Recognition Test, the Voice Emotion Recognition Test, and the Reading the Mind in the Eyes Test. The Short Recognition Memory Test for Faces was used as a control measure. The Schedule for the Assessment of Negative Symptoms, Schedule for the Assessment of Positive Symptoms, and Beck Depression Inventory were used to rate of patient symptoms. There were 100 patients with the following genotypes: Val/Val (21), Met/Met (30), and Val/Met (49). The genotype distribution of polymorphism of Val158Met COMT did not differ between the patient and control groups. Schizophrenia carriers of the Val/Val genotype performed worse in social cognitive measures, in comparison with the other groups. No statistically significant correlations were recorded between age at schizophrenia onset and polymorphism of Val158Met COMT. There was an influence of genotype in the control group: the Met homozygotes performing better. Schizophrenia patients homozygous for the Val allele showed significant disadvantages over patients homozygous or heterozygous for the Met allele in social cognitive processes. The COMT genotype may not, however, contribute to the age of onset of schizophrenia. 相似文献
70.