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91.
92.
Antifungal activities were examined and compared for some 40 kinds of aliphatic and aromatic aldehydes, alcohols, phenolic compounds, ether compounds and hydrocarbons from essential oils and for some related compounds, using seven fungi.  相似文献   
93.
Binding of melatonin by rat thymus membranes exhibited diurnal changes. Binding increased during the daytime and reached maximal values before entering the dark period. Then, binding decreased rapidly during the dark phase. In rats kept in light at night, binding of [125I]melatonin by membranes was significantly higher than in animals that entered the normal dark period. Neonatal pinealectomy, which suppresses the circadian rhythm of melatonin, led to an increase in melatonin binding of 106%. Moreover, in animals maintained under continuous light exposure, which corresponds to functional pinealectomy, binding of melatonin by thymus membranes also increased in a time-dependent manner. The results support the hypothesis of a regulatory role of melatonin in the thymus in which melatonin downregulates its own binding sites.  相似文献   
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The properties of the neutral proteolytic activity concentrated in a fraction (F–1) separated from rabbit muscle homogenate were examined by measuring the effects of various reagents and metal ions, the time course of the proteolysis and Ca-stability. The obtained results have indicated that F–1 contains two types of neutral protease active on proteins, tentatively named Protease I and II, The former, which is activated by Ca2+ and Ca-labile, shows an explosive production of Cu-Folin phenol reagent positive materials at the early stage of incubation. The latter, which is Ca-stable, shows a large production of ninhydrin positive materials throughout the incubation time. The proteolysis by F–1 was similar to the autolysis of muscle homogenate in all the properties examined. Therefore, Proteases I and II were assumed to be main enzymes responsible for the muscle proteolysis at the neutral pH region. As there has been no factor denying their functioning in living muscle, it is probable that Proteases I and II take important parts in the muscle catabolism.  相似文献   
96.
Aim of the studyTo evaluate the performance of the 99mTc-Sestamibi parathyroid scintigraphy and to compare it with the performance of cervical ultrasonography in patients with secondary hyperparathyroidism who are candidates for parathyroidectomy.Patients and methodsWe performed a retrospective study including 20 patients with severe secondary hyperparathyroidism who underwent parathyroid scintigraphy in the nuclear medicine department of Sfax, during the period between January 2009 and June 2012. Our two days protocol included dual-phase, MIBI/Tc subtraction and single photon emission photons (SPECT) techniques. We analyzed the results obtained from each technique alone, then from combinations thereof. For all patients, we have collected the surgical and histopathological data as well cervical ultrasound if available.ResultsThe subtraction technique was the best performing with a sensitivity of 47% and an accuracy of 55%. The combination of subtraction scintigraphy and SPECT has improved the sensitivity to 53%and accuracy to 57%. The combined lecture of ultrasound and scintigraphy has given the best performance with a sensitivity of 58%, a specificity of 83% and an accuracy of 66%.ConclusionParathyroid scintigraphy combining subtraction and SPECT showed better reliability. The coupling with ultrasound is essential to improve results. The poor performance of scintigraphy in secondary hyperparathyroidism implies that it should be required only to search for ectopic or supernumerary glands.  相似文献   
97.
Thyroid ectopia is a rare disease (1/4000 to 1/8000 patients with hypothyroidism) whose pathogenesis is poorly understood. It may be asymptomatic or present with clinical or biological hypothyroidism. We report the observation of ectopic thyroid diagnosed in a 42-year-old patient. On physical examination, there was no signs of hypothyroidism and thyroid was not palpable. In thyroid scintigraphy, this training is an ectopic thyroid tracheal pre-position. The SPECT/CT cervical examination confirmed the presence of lobed hyoid in training and examination of the thyroid empty lodge. We discuss in this article the clinical and radiological features of this pathology and we insist on the necessity to consider this diagnosis before any hypothyroidism associated with the absence of palpation of thyroid gland in normal position even in adults.  相似文献   
98.
99.
Female Drosophila melanogaster frequently mate with multiple males, and the success of a given male depends not only on his genotype but also on the genotype of his competitor. Here, we assess how natural genetic variation affects male–male interactions for traits influencing pre‐ and postcopulatory sexual selection. Males from a set of 66 chromosome substitution lines were competed against each other in a ‘round‐robin’ design, and paternity was scored using bulk genotyping. We observed significant effects of the genotype of the first male to mate, the second male to mate and an interaction between the males for measures of male mating rate and sperm utilization. We also identified specific combinations of males who show nontransitive patterns of reproductive success and engage in ‘rock‐paper‐scissors’ games. We then tested for associations between 245 polymorphisms in 32 candidate male reproductive genes and male reproductive success. We identified eight polymorphisms in six reproductive genes that associate with male reproductive success independent of the competitor (experimentwise < 0.05). We also identified four SNPs in four different genes where the relative reproductive success of the alternative alleles changes depending on the competing males' genetic background (experimentwise < 0.05); two of these associations include premature stop codons. This may be the first study that identifies the genes contributing to nontransitivity among males and further highlights that ‘rock‐paper‐scissors’ games could be an important evolutionary force maintaining genetic variation in natural populations.  相似文献   
100.
Sperm competition is a powerful and widespread evolutionary force that drives the divergence of behavioural, physiological and morphological traits. Elucidating the mechanisms governing differential fertilization success is a fundamental question of sperm competition. Both sperm and nonsperm ejaculate components can influence sperm competition outcomes. Here, we investigate the role of a nonsemen copulatory fluid in sperm competition. Male Japanese quail possess a gland that makes meringue‐like foam. Males produce and store foam independent of sperm and seminal fluid, yet transfer foam to females during copulation. We tested whether foam influenced the outcome of sperm competition by varying foam state and mating order in competitive matings. We found that the presence of foam from one male decreased the relative fertilization success of a rival, and that foam from a given male increased the probability he obtained any fertilizations. Mating order also affected competitive success. Males mated first fertilized proportionally more eggs in a clutch and had more matings with any fertilizations than subsequent males. We conclude that the function of foam in sperm competition is mediated through the positive interaction of foam with a male's sperm, and we speculate whether the benefit is achieved through improving sperm storage, fertilizing efficiency or retention. Our results suggest males can evolve complex strategies to gain fertilizations at the expense of rivals as foam, a copulatory fluid not required for fertilization, nevertheless, has important effects on reproductive performance under competition.  相似文献   
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