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141.
A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF‐7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC‐27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound 17b exhibited the most potent activity (IC50 4.6 μM) against HGC‐27 as compared with the reference compound, sindaxel (IC50 10.3 μM), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177–188, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   
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Although Ficus (Moraceae) is a keystone plant genus in the tropics, providing resources to many frugivorous vertebrates, its population genetic structure, which is an important determinant of its long‐term survival, has rarely been investigated. We examined the population genetic structure of two dioecious fig species (Ficus hispida and Ficus exasperata) in the Indian Western Ghats using co‐dominant nuclear microsatellite markers. We found high levels of microsatellite genetic diversity in both species. The regression slopes between genetic relationship coefficients (fij) and spatial distances were significantly negative in both species indicating that, on average, individuals in close spatial proximity were more likely to be related than individuals further apart. Mean parent–offspring distance (σ) calculated using these slopes was about 200 m in both species. This should be contrasted with the very long pollen dispersal distances documented for monoecious Ficus species. Nevertheless, overall population genetic diversity remained large suggesting immigrant gene flow. Further studies will be required to analyze broader scale patterns.  相似文献   
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Factors relating to photo-oxidative damage in tomatoes were investigated during maturation of the fruit and upon induction of sunscald. Superoxide dismutase (SOD) activity passed through a minimum at the mature-green and breaker stages of ripening and availability of zinc and copper did not appear to be a limiting factor in the synthesis of the enzyme. Iron levels were maximal and total carotenoid concentrations were lowest during the same mature-green and breaker stages of maturation, while chlorophyll was starting to decrease but was still present in large amounts. Peroxidase activity decreased steadily during ripening. Artificial induction of tolerance to photodynamic damage by controlled heat treatment was accompanied by an increase in SOD activity, while carotenoid levels and peroxidase activity did not change. These findings support the thesis that the previously reported susceptibility of tomatoes to photodynamic damage, i.e. sunscald, during the mature-green and breaker stages of maturation is related to enhanced formation of superoxide ions, at a time when chloroplast structure begins to break down. SOD, by scavenging the superoxide, appears to supplement the protective action of carotenoids against photo-oxidative injury.  相似文献   
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Congenital amusia is a neurogenetic disorder of music processing that is currently ascribed to a deficit in pitch processing. A recent study challenges this view and claims the disorder might arise as a consequence of a general spatial-processing deficit. Here, we assessed spatial processing abilities in two independent samples of individuals with congenital amusia by using line bisection tasks (Experiment 1) and a mental rotation task (Experiment 2). Both amusics and controls showed the classical spatial effects on bisection performance and on mental rotation performance, and amusics and controls did not differ from each other. These results indicate that the neurocognitive impairment of congenital amusia does not affect the processing of space.  相似文献   
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Space use including territoriality and spatial arrangement within a population can reveal important information on the nature, dynamics, and evolutionary maintenance of alternative strategies in color polymorphic species. Despite the prevalence of color polymorphic species as model systems in evolutionary biology, the interaction between space use and genetic structuring of morphs within populations has rarely been examined. Here, we assess the spatial and genetic structure of male throat color morphs within a population of the tawny dragon lizard, Ctenophorus decresii. Male color morphs do not differ in morphology but differ in aggressive and antipredator behaviors as well as androgen levels. Despite these behavioral and endocrine differences, we find that color morphs do not differ in territory size, with their spatial arrangement being essentially random with respect to each other. There were no differences in genetic diversity or relatedness between morphs; however, there was significant, albeit weak, genetic differentiation between morphs, which was unrelated to geographic distance between individuals. Our results indicate potential weak barriers to gene flow between some morphs, potentially due to nonrandom pre‐ or postcopulatory mate choice or postzygotic genetic incompatibilities. However, space use, spatial structure, and nonrandom mating do not appear to be primary mechanisms maintaining color polymorphism in this system, highlighting the complexity and variation in alternative strategies associated with color polymorphism.  相似文献   
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Dielectric spectroscopy is a non-invasive contact technique that permits the in vivo measurement of the specific electrical properties of biological tissue induced by an external electrical field. Permittivity, relaxation time and specific conductivity as a function of corneal hydration (wet weight/dry weight) and temperature were measured in 10 porcine corneas. Variation of tissue hydration has a minor influence on the signal, with a significant variation of the signal being detectable only for relatively dry tissue. A much greater influence was found for temperature, in particular on relaxation times. Dielectric spectroscopy provides us with an opportunity to detect structural, in particular temperature-induced, changes in living tissue. In the frequency range investigated, hydration has only a small influence on the dielectric properties of the tissue.  相似文献   
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