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51.
Evidence for the secondary sexual development of the anal fin in female kokanee salmon Oncorhynchus nerka
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This study examines whether the anal fin undergoes secondary sexual development similar to other reproductive traits in salmonids. This hypothesis was tested by comparing the anal‐fin size of female kokanee salmon Oncorhynchus nerka that were in the early and late stages of sexual development. Females in an advanced stage of maturation had significantly larger anal fins relative to females in an early state of maturation (+4–7%), indicating that the anal fin undergoes secondary sexual development. The magnitude of this secondary growth was comparable with snout length (+9–10%), which is known to undergo secondary sexual development in female salmonids. When morphological trait dimensions were compared between the sexes, the anal fin was the only morphological trait found to have a female‐biased sexual size dimorphism. This is the first study to show that the anal fin of female salmonids undergoes secondary sexual development. 相似文献
52.
We investigated the prevalence and phenotypic variation of Candida species in oral lichen planus (OLP) and the therapeutic implications of our findings. Eighty patients with clinically and histopathologically confirmed cases of OLP (64 non-erosive, 16 erosive) and a control group of 80 healthy individuals with no predisposing factors for oral candidiasis were examined for evidence of Candida infection. Oral swabs and smears were obtained for cytology and culture. Identification, speciation and antifungal susceptibility tests of Candida isolates were performed using an automated microbial identification system. Fifty percent of erosive OLP cases, 28% of non-erosive cases and none of the controls showed evidence of Candida. Candida albicans was found predominantly in non-erosive OLP, while other Candida species were predominate in erosive OLP. Non-Candida albicans isolates (C. glabrata, C. krusei) were resistant to the commonly used antifungals, clotrimazole and fluconazole. Candida infection is common in cases of OLP. We recommend antifungal sensitivity testing prior to antifungal therapy for the erosive form of OLP. 相似文献
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An oxystat was designed to enable maintenance of very low, predetermined oxygen tensions (below 1 microM) in incubated suspensions of synaptosomes. The oxygen thresholds for the energy state (ATP and creatine phosphate levels), for lactate production, and for acetylcholine release were compared. The approximate thresholds (microM O2) in veratridine-stimulated preparations were: oxygen consumption, 10; ATP, 10; creatine phosphate, 15; lactate release, 20; and acetylcholine release, 25. The results for release of total acetylcholine and of the acetylcholine newly synthesized from [14C]glucose were indistinguishable. The results from this study are discussed in relation to hypoxia and to reported in vivo observations. 相似文献
54.
Seventy-three patients were studied after ingesting a liquid glucose meal, tagged with 113Indium. Nineteen of these patients were awaiting surgery for their duodenal ulcer, while 54 were studied postoperatively, 25 of whom experienced troublesome postprandial (dumping) symptoms in their daily lives. The radioactive marker emptied significantly faster in the symptomatic patients than in the symptomfree, pre and post-operative groups (initial emptying rate 3.45 ± 0.23, compared with 1.16 ± 0.19 and 1.27 ± 0.15% fall in counts/min respectively; p < 0.01). Initial (20 min) rises in the plasma concentrations of neurotensin-like immunoreactivity measured during the test correlated significantly with the rate of gastric emptying in all patients, being greatest in patients with dumping symptoms. Physiological concentrations of neurotensin have been shown to delay gastric emptying. The excessive rise in plasma neurotensin-like immunoreactivity in patients with dumping symptoms, presumably occuring as a result of the rapid passage of nutrients to the neurotensin-rich ileum, may possibly have a compensatory role in slowing further emptying from the stomach. 相似文献
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Despite recent advances in spectroscopic techniques, there is uncertainty regarding the nature of the carbonyl groups in the asphaltene and resin fractions of crude oil, information necessary for an understanding of the physical properties and environmental fate of these materials. Carbonyl and hydroxyl group functionalities are not observed in natural abundance 13C nuclear magnetic resonance (NMR) spectra of asphaltenes and resins and therefore require spin labeling techniques for detection. In this study, the carbonyl functionalities of the resin and asphaltene fractions from a light aliphatic crude oil that is the source of groundwater contamination at the long term USGS study site near Bemidji, Minnesota, have been examined through reaction with 15N-labeled hydroxylamine and aniline in conjunction with analysis by solid and liquid state 15N NMR. Ketone groups were revealed through 15N NMR detection of their oxime and Schiff base derivatives, and esters through their hydroxamic acid derivatives. Anilinohydroquinone adducts provided evidence for quinones. Some possible configurations of the ketone groups in the resin and asphaltene fractions can be inferred from a consideration of the likely reactions that lead to heterocyclic condensation products with aniline and to the Beckmann reaction products from the initially formed oximes. These include aromatic ketones and ketones adjacent to quaternary carbon centers, β-hydroxyketones, β-diketones, and β-ketoesters. In a solid state cross polarization/magic angle spinning (CP/MAS) 15N NMR spectrum recorded on the underivatized asphaltene as a control, carbazole and pyrrole-like nitrogens were the major naturally abundant nitrogens detected. 相似文献
59.
Christine Maric Carol Forsblom Lena Thorn Johan Wadén Per-Henrik Groop 《Steroids》2010,75(11):772-778
Male sex is a risk factor for development and progression of diabetic nephropathy; however, the relationship between sex hormone levels and diabetic nephropathy in type 1 diabetic men is unknown. This was a prospective follow-up study as part of the nationwide Finnish Diabetic Nephropathy (FinnDiane) Study; 297 patients were followed for 5.9 ± 1.5 years. Serum total testosterone (Tt) and estradiol (Te), calculated free testosterone (cFt) and estradiol (cFe) and sex hormone binding globulin were measured at baseline and correlated with urinary albumin excretion rate, estimated glomerular filtration rate and markers of metabolic syndrome. Diabetes without renal disease was associated with decreased Tt (p < 0.001), Te (p < 0.001) and cFt (p = 0.001) levels compared with healthy non-diabetic men. With progression of renal disease from micro- to macroalbuminuria, this decrease in serum Tt was even more pronounced. Cox regression showed that cFt and cFe were independent predictors of the progression from macroalbuminuria to end-stage renal disease. Our study shows that men with type 1 diabetes exhibit dysregulated sex hormone levels, which is most pronounced in men with progressive renal disease, suggesting that sex hormones may play a role in the pathogenesis of diabetic nephropathy associated with type 1 diabetes. 相似文献
60.
Osbert J. Sun Gerty J. Gielen Roger Sands Tattersall C. Smith Alan J. Thorn 《Trees - Structure and Function》2001,15(6):335-340
We investigated effects of low Mg and moderately raised NaCl, as occurs in plantations irrigated with tertiary municipal effluent in New Zealand, on growth, Mg nutrition and photosynthetic activity of Pinus radiata D. Don seedlings grown in nutrient solutions with a Perlite medium. Seedlings were grown with either sufficient (0.35 mM; H[Mg]) or limited (0.033 mM; L[Mg]) Mg supply, without NaCl or with NaCl addition (8.7 mM; +[NaCl]). After 30 weeks, seedlings grown at L[Mg] displayed severe Mg deficiency symptoms, and had significantly less biomass than those at H[Mg]. While NaCl addition had an adverse effect on seedling growth at H[Mg], it increased growth at L[Mg]. The +[NaCl] treatment greatly increased the Mg uptake rates, which were associated with increased stomatal conductance and increased root to shoot ratio. Magnesium deficiency reduced the rates of light-saturated photosynthesis and stomatal conductance, but not the quantum efficiency of photosystem II, which was reduced mainly by the +[NaCl] treatment, especially at H[Mg]. Our study clearly indicated that NaCl addition could counteract the impact of low Mg supply by enhancing Mg uptake from the rooting medium. 相似文献