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101.
Autistic behavior is often accompanied by numerous disturbing symptoms on the part of gastrointestinal system, such as abdominal pain, constipation or diarrhea. These problems are often connected with deregulation of physiological microflora in intestine. The aim of this study was to determine differences in intestinal microflora of autistic and healthy children. Strains of Clostridium spp. and enterococci were isolated more frequently from stool samples of autistic children and rarely lactobacilli. Quantitative differences were observed maliny among staphylococci, Candida spp. and Clostridium perfringens. Monitoring and stabilization of intestinal microflora and knowledge about role of particular strains in etiology of autistic disorders can increase the chances for appropriate therapy.  相似文献   
102.
This work covers the four years (2002-2005) observations on the occurrence and numerousness of Phyllonorycter robiniella (Clem.) and their natural regulation by parasitoid complex in Kraków area. The highest infestation by P. robiniella was found in year 2003 when almost 100% of Leaves and 90% of leaflets was infested. During the vegetation period the density of the observed mines increased and reached the maximum in August in all years of observations. The most important factor decreasing the number of P. robiniella was parasitization. The parasitization ranged between 18% and 27% depends on year of observation. Generally the highest parasitization was noted in the end of growing season, in September after the maximum of pest abundance. The most common parasitoids were Hymenoptera from the family Eulophidae (Chalcidoidea).  相似文献   
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Humulus lupulus (Cannabaceae) is well known throughout the world as a raw material in the brewing industry. The antioxidative action of hop cones is poorly understood, therefore the aim of our present study was to investigate in vitro changes in human plasma induced by peroxynitrite in the presence of the highly purified extract from hop cones (Humulus lupulus). The aim of our study was also to explain the effect of the extract from hop cones on coagulation activity of human plasma treated with peroxynitrite. The action of the extract from hop cones was compared with the properties of a well-characterized commercial monomeric polyphenol — resveratrol (3,4′,5-trihydroxystilbene). The tested plant extract, like resveratrol, significantly inhibited protein carbonylation and nitration in plasma treated with ONOO(0.1 mM). The extract from hop cones, like resveratrol, also caused a distinct reduction of plasma lipid peroxidation induced by ONOO. Moreover, the tested extract modulated the coagulation properties of plasma treated with peroxynitrite. It seems that antioxidative activities of the highly purified extract from hop cones may be responsible for its medicinal properties.  相似文献   
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The expression of glutathione S-transferase pi (GST pi), an enzyme responsible for inactivation of a large variety of toxic compounds was studied in spinal cord, motor and sensory brain cortex obtained from patients who died in the course of amyotrophic lateral sclerosis (ALS). The studies were performed on formalin-fixed, paraffin-embedded (FFPE) and freshly frozen tissues. The method of RNA isolation from FFPE was modified. A significant decrease of GST pi-mRNA expression was found in cervical spinal cord and motor brain cortex of ALS subjects comparing to analogue control tissues (P < 0.01), as well as in motor cortex of ALS subjects comparing to their sensory cortex (P < 0.05). In spinal cords the decrease in GST pi-mRNA expression was accompanied by a decrease of GST pi protein level. Results indicated lowered GST pi expression on both mRNA and protein levels in the regions of nervous system affected by ALS. The non-properly inactivated by GST toxic electrophiles and organic peroxides may thus contribute to motor neurons damage.  相似文献   
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Novel, flexible arylpiperazine gepirone analogs (1a-3a) with a mixed 5-HT1A/5-HT2A receptor profile, low D2 receptor affinity, and agonistic (2a) or partial agonistic (1a, 3a) activity toward 5-HT1A receptor sites were synthesized. Their conformationally restricted counterparts (1b-3b) were selective 5-HT1A ligands (over 5-HT2A and D2 receptors), which turned out to be agonists (2b, 3b), or partial agonist (1b) of 5-HT1A receptors.  相似文献   
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Sex allocation theory predicts that parents should bias their reproductive investments toward the offspring sex generating the greatest fitness return. When females are the heterogametic sex (e.g., ZW in butterflies, some lizards, and birds), production of daughters is associated with an increased risk of offspring inviability due to the expression of paternal, detrimental recessives on the Z chromosome. Thus, daughters should primarily be produced when mating with partners of high genetic quality. When female sand lizards (Lacerta agilis) mate with genetically superior males, exhibiting high MHC Class I polymorphism, offspring sex ratios are biased towards daughters, possibly due to recruitment of more Z-carrying oocytes when females have assessed the genetic quality of their partners. If our study has general applicability across taxa, it predicts taxon-specific sex allocation effects depending on which sex is the heterogametic one.  相似文献   
110.
Rhodopsin (Rho) is a G protein-coupled receptor that initiates phototransduction in rod photoreceptors. High expression levels of Rho in the disc membranes of rod outer segments and the propensity of Rho to form higher oligomeric structures are evident from atomic force microscopy, transmission electron microscopy, and chemical cross-linking experiments. To explore the structural and functional properties of Rho in n-dodecyl-beta-maltoside, frequently used to purify heterologously expressed Rho and its mutants, we used gel filtration techniques, blue native gel electrophoresis, and functional assays. Here, we show that in micelles containing n-dodecyl-beta-maltoside at concentrations greater than 3 mM, Rho is present as a single monomer per detergent micelle. In contrast, in 12 mM 3-[(3-cholamidopropyl)dimethyl-ammonio]-1-propanesulfonate (CHAPS), micelles contain mostly dimeric Rho. The cognate G protein transducin (Gt) appears to have a preference for binding to the Rho dimer, and the complexes fall apart in the presence of guanosine 5'-3-O-(thio)triphosphate. Cross-linked Rho dimers release the chromophore at a slower rate than monomers and are much more resistant to heat denaturation. Both Rho(*) monomers and dimers are capable of activating Gt, and both of them are phosphorylated by Rho kinase. Rho expressed in HEK293 cells is also readily cross-linked by a bifunctional reagent. These studies provide an explanation of how detergent influences the oligomer-dimermonomer equilibrium of Rho and describe the functional characterization of Rho monomers and dimers in detergent.  相似文献   
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