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31.
Twenty microsatellite loci were identified from genomic DNA enrichment and expressed sequence tags of entomopathogenic nematode Heterorhabditis bacteriophora. Eight loci were found to be polymorphic in a Northeast Ohio H. bacteriophora population. Levels of polymorphism were evaluated in 31-56 individuals and the number of alleles ranged from two to three. The values of observed and expected heterozygosities ranged from 0 to 0.536 and from 0.223 to 0.616, respectively. All eight loci showed heterozygote deficiencies, but three conformed to Hardy-Weinberg equilibrium at the subpopulation level. This is the first set of microsatellite markers in entomopathogenic nematodes.  相似文献   
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Minutes comprise > 50 phenotypically similar mutations scattered throughout the genome of Drosophila, many of which are identified as mutations in ribosomal protein (rp) genes. Common traits of the Minute phenotype are short and thin bristles, slow development, and recessive lethality. By mobilizing a P element inserted in the 5'' UTR of M(3)95A, the gene encoding ribosomal protein S3 (RPS3), we have generated two homozygous viable heteroalleles that are partial revertants with respect to the Minute phenotype. Molecular characterization revealed both alleles to be imprecise excisions, leaving 40 and 110 bp, respectively, at the P-element insertion site. The weaker allele (40 bp insert) is associated with a approximately 15% decrease in RPS3 mRNA abundance and displays a moderate Minute phenotype. In the stronger allele (110 bp insert) RPS3 mRNA levels are reduced by approximately 60%, resulting in an extreme Minute phenotype that includes many morphological abnormalities as well as sterility in both males and females due to disruption of early gametogenesis. The results show that there is a correlation between reduced RPS3 mRNA levels and the severity of the Minute phenotype, in which faulty differentiation of somatic tissues and arrest of gametogenesis represent the extreme case. That heteroalleles in M(3)95A can mimic the phenotypic variations that exist between different Minute/rp-gene mutations strongly suggests that all phenotypes primarily are caused by reductions in maximum protein synthesis rates, but that the sensitivity for reduced levels of the individual rp-gene products is different.  相似文献   
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The purpose of this study was to investigate the effect of clomiphene citrate and human chorionic gonadotropin (HCG) on the structural changes, as well as the evaluation of the expression of cation channel sperm‐associated protein 1 (CatSper1), cation channel sperm‐associated protein 2 (CatSper2), luteinizing hormone/choriogonadotropin receptor (LHCGR), and steroidogenic factor 1 (SF1) genes in testicular tissue of rats. All rats divided into five groups as follows; G1 as the control group that received normal saline, G2 received olive oil, G3 received 100 IU/kg HCG, G4 received 5 mg/kg clomiphene citrate, and G5 received 5 mg/kg clomiphene citrate and 100 IU/kg HCG. At the end of the experiment period, Day 56, blood samples were taken and the serum was isolated. Then, histomorphometric analysis, hormonal assess, and real‐time polymerase chain reaction to measure the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were performed. The results showed that the concentrations of testosterone, follicle‐stimulating hormone, and luteinizing hormone were decreased in the G4 group, whereas these parameters were increased in the G3 group. A comparison of the sperm quality indicated a significant reduction in the quality of sperm cells in the G4 group compared with other groups. The quality of sperm was significantly enhanced in the G3 and G5 groups in comparison with the G1 group. Also, our findings demonstrated that the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were significantly elevated in the G3 group when compared with other experimental groups. According to the obtained results, it seems that clomiphene citrate reduces the process of spermatogenesis and the detrimental impacts of this compound would be neutralized by the administration of HCG.  相似文献   
35.
The absolute configuration of (+)-isoshinanolone, a wide-spread acetogenic metabolite from higher plants, has been determined by X-ray structure analysis of its new dibromide; accordingly, this natural tetralone is 3R,4R-configured, in agreement with previous degradative results. In addition, a first chiroptical on-line stereoanalysis for isoshinanolones is presented, i.a. by HPLC on a chiral phase coupled to CD spectroscopy, giving pure CD spectra of all of the four stereoisomers of isoshinanolone directly from stereoisomeric mixtures.  相似文献   
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Particulate matter (PM) is an air contaminant in urban and industrial areas that often exceeds limit values, creating serious problems due to its harmful effects on health. Planting trees and shrubs as air filters is a way to improve air quality in these areas. However,further knowledge on species effectiveness in air purification is essential This study compared four species of tree (Acer campestre L, Fraxinus excelsior L, Platanus x hispanica Mill. ex Muenchh. 'Acerifolia', Tilia cordata Mill.), three species of shrub (Forsythia x intermedia Zabel, Physocarpus opulifolius (L.) Maxim., Spiraea japonica L.), and one climber species (Hedera helix L) that are commonly cultivated along streets in Poland to capture fine, coarse and larger particles from air. Separate gravimetric analyses were performed to quantify PM deposited on surfaces and trapped in waxes. Significant differences were found between the plant species tested. The distribution of different particle size fractions differed between and within species and also between leaf surfaces and in waxes.  相似文献   
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