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101.
The aim of the present study was to measure zinc (Zn) and iron (Fe) concentration in human semen and superoxide dismutase (SOD) activity in seminal plasma and correlate the results with sperm quality. Semen samples were obtained from men (N = 168) undergoing routine infertility evaluation. The study design included two groups based on the ejaculate parameters. Group I (n = 39) consisted of males with normal ejaculate (normozoospermia), and group II (n = 129) consisted of males with pathological spermiogram. Seminal Zn and Fe were measured in 162 samples (group I, n = 38; group II, n = 124) and SOD activity in 149 samples (group I, n = 37; group II, n = 112). Correlations were found between SOD activity and Fe and Zn concentration, and between Fe and Zn concentration. SOD activity was negatively associated with volume of semen and positively associated with rapid progressive motility, nonprogressive motility, and concentration. Negative correlation was stated between Fe concentration and normal morphology. Mean SOD activity in seminal plasma of semen from men of group I was higher than in seminal plasma of semen from men of group II. Fe concentration was higher in teratozoospermic males than in males with normal morphology of spermatozoa in group II. Our results suggest that Fe may influence spermatozoa morphology.  相似文献   
102.
Bacterial thyroiditis is a rare disease, and one of which the clinical symptoms and signs are frequently misleading. On the other hand, prompt diagnosis is crucial for successful treatment. We report the case of an 82 year-old man with diabetes mellitus type 2 and a history of steroid treatment who presented with severe odynophagia and dysphagia associated with fever, chills, sore throat and right ear pain. Based on the clinical picture, radiological studies, thyroid cytology, blood and thyroid aspirate culture, suppurative thyroiditis caused by Salmonella enteritidis was diagnosed. The patient was successfully treated with antibiotics and surgical drainage.  相似文献   
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Crystal structures of the PDZ2 domain of the scaffolding protein syntenin, both unbound and in complexes with peptides derived from C termini of IL5 receptor (alpha chain) and syndecan, reveal the molecular roots of syntenin's degenerate specificity. Three distinct binding sites (S(0), S(-1), and S(-2)), with affinities for hydrophobic side chains, function in a combinatorial way: S(-1) and S(-2) act together to bind syndecan, while S(0) and S(-1) are involved in the binding of IL5Ralpha. Neither mode of interaction is consistent with the prior classification scheme, which defined the IL5Ralpha interaction as class I (-S/T-X-phi) and the syndecan interaction as class II (-phi-X-phi). These results, in conjunction with other emerging structural data on PDZ domains, call for a revision of their classification and of the existing model of their mechanism.  相似文献   
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One goal of post‐fire native species seeding is to increase plant community resistance to exotic weed invasions, yet few studies address the impacts of seeding on exotic annual establishment and persistence. In 2010 and 2011, we investigated the influence of seedings on exotic annuals and the underlying microbial communities. The wildfire site in northern Utah was formerly dominated by Artemisia tridentata ssp. wyomingensis, but burned in September 2008. Experimental seeding treatments were installed in November 2008 to examine strategies for establishing native species using two drills, hand broadcasts and different timing of seed applications (resulting in 13 seeding treatments). We collected aboveground biomass of invasive annuals (Halogeton glomeratus, Salsola kali, and Bromus tectorum), other volunteer plants from the extant seed bank, and seeded species from all treatments in the second and third years after fire. We sampled soils within microsites beneath native perennial bunchgrass and exotic annuals to characterize underlying soil microbial communities. High precipitation following seeding led to strong seedling establishment and we found few differences between seeding treatments established with either drill. All seeded treatments reduced exotic biomass by at least 90% relative to unseeded controls. Soil microbial communities (phospholipid fatty acid analysis), beneath B. tectorum, Poa secunda, and Pseudoroegneria spicata microsites differed little 3 years after fire. However, microbial abundance beneath P. spicata increased from June to July, suggesting that microbial communities beneath successful seedings can vary greatly within a single growing season.  相似文献   
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