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211.
Silvio Garattini 《Obesity (Silver Spring, Md.)》1995,3(Z4):463S-470S
The present status of knowledge on drugs affecting food intake and presumably acting via a serotoninergic mechanism is reviewed. The mechanism of action of these drugs is analyzed at the neurochemical level. All the drugs, to various extents, inhibit the uptake of serotonin (5HT), increase the release of 5HT and decrease brain levels of 5HT and 5HIAA. However, the underlying mechanisms are not identical as exemplified by comparisons made with d-fenfluramine, d-norfenfluramine, fluoxetine, sertraline and paroxetine. An analysis of the role of 5HT in the inhibition of food intake reveals that only d-fenfluramine is inhibited by antiserotonin agents. The role of the different 5HT receptor-subtypes in this antagonism is discussed. More selective 5HT antagonists are needed to establish which 5HT receptor(s) controls food intake. 相似文献
212.
The ascorbate system and lipid peroxidation in stored potato (Solanum tuberosum L.) tubers 总被引:1,自引:0,他引:1
The changes in the components of the ascorbateglutathione systemduring the storage of potato (Solanum tuberosum L. cv. Spunta)tubers for 40 weeks at both 3C and 9C were studied in relationto lipid peroxidation. The level of malondialdehyde was foundto be higher at 3C than at 9C throughout storage. Thus, lipidperoxidation, which is the main cause of membrane deterioration,was accelerated at the lower temperature. Catalase activityincreased throughout storage independently of temperature. Theascorbate content of tubers decreased during storage both at3C and at 9C, as in other ageing processes. However, ascorbateperoxidase activity reached a maximum after about 8 weeks ofstorage, then declined at 9C, but held a higher level at 3C.The dehydroascorbic content also reached a maximum after about8 weeks and was significantly higher in tubers stored at 3C.These findings indicate a greater utilization of ascorbate byascorbate peroxidase at the lower temperature. Ascorbate freeradical reductase, dehydroascorbate reductase and glutathionereductase, the enzymes involved in the regeneration of ascorbate,were not affected by temperature and remained quite unchangedthroughout storage. It can be concluded that the ascorbate systemis involved in the scavenging of the free-radicals responsiblefor lipid peroxidation in stored potato tubers, at least atlow temperatures and in the first period of storage. Key words: Ascorbate, lipid peroxidation, potato tubers, Solanum tuberosum L 相似文献
213.
Ester S. Ramos Carlos A. Moreira-Filho Yvone A. M. V. A. Vicente Maria A. S. Llorach-Velludo Silvio Tucci Jr. Maria H. O. Duarte Amélia G. Araújo Lucia Martelli 《Human genetics》1996,97(5):596-598
Two 46,XX true hermaphrodites and one XX male without genital ambiguities are reported. They coexist in two generations of the same pedigree, with paternal transmission and in the absence of SRY (sex-determining region, Y chromosome). These familial cases provide evidence to support the hypothesis that these disorders are alternative manifestations of the same genetic defect, probably an autosomal dominant mutation (with incomplete penetrance) or an X-linked mutation (limited by the presence of the Y chromosome). 相似文献
214.
Effective population size as a driver for divergence of an antimicrobial peptide (Hymenoptaecin) in two common European bumblebee species
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H. Michael G. Lattorff Mario Popp Susann Parsche Sophie Helbing Silvio Erler 《Biological journal of the Linnean Society. Linnean Society of London》2016,119(2):299-310
Social insects are the target of numerous pathogens. This is because the high density of closely‐related individuals frequently interacting with each other enhances the transmission and establishment of pathogens. This high selective pressure results in the rapid evolution of immune genes, which might be counteracted by a reduced effective population size (Ne) lowering the effectiveness of selection. We tested the effect of Ne on the evolutionary rate of an important immune gene for the antimicrobial peptide Hymenoptaecin in two common central European bumblebee species: Bombus terrestris and Bombus lapidarius. Both species are similar in their biology and are expected to be under similar selective pressures because pathogen prevalence does not differ between species. However, previous studies indicated a higher Ne in B. terrestris compared to B. lapidarius. We found high intraspecific variability in the coding sequence but low variability for silent polymorphisms in B. lapidarius. Estimates of long‐ and short‐term Ne were three‐ to four‐fold higher Ne in B. terrestris, although the species did not differ in census population sizes. The difference in Ne might result in less efficient selection and suboptimal adaptation of immune genes (e.g. hymenoptaecin) in B. lapidarius, and thus this species might become less resistant and more tolerant, turning into a superspreader of diseases. 相似文献
215.
Silvio Renato Oliveira Menegassi Gabriel Ribas Pereira Carolina Bremm Celso Koetz Flávio Guiselli Lopes Eduardo Custódio Fiorentini Concepta McManus Eduardo Antunes Dias Marcela Kuczynski da Rocha Rubia Branco Lopes Júlio Otávio Jardim Barcellos 《International journal of biometeorology》2016,60(11):1787-1794
216.
Carla Tatone Elisabetta Benedetti Maurizio Vitti Giovanna Di Emidio Rosanna Ciriminna Maria Elena Vento Vito Cela Placido Borzì Gaspare Carta Monica Lispi Anna Maria Cimini Paolo Giovanni Artini on Behalf of Italian Society of Embryology Reproduction Research 《Journal of cellular physiology》2016,231(4):908-914
217.
Nature of foulants and fouling mechanism in the Protein A MabSelect resin cycled in a monoclonal antibody purification process
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218.
Structural and functional characteristics of virgin and fouled Protein A MabSelect resin cycled in a monoclonal antibody purification process
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219.
A. Vetuschi A. D’Alfonso R. Sferra D. Zanelli S. Pompili F. Patacchiola E. Gaudio G. Carta 《European journal of histochemistry : EJH》2016,60(1)
The objective of this study was to evaluate the morphological and immunohistochemical alterations of tissue removed from the upper third of anterior vaginal wall in a sample group of the female population presenting homogenous risk factors associated with pelvic organ prolapse (POP). The case study consisted of 14 patients with POP and there were 10 patients in the control group. Patient selection was carried on the basis of specific criteria and all of the patients involved in the study presented one or more of the recognized POP risk factors. Samples were taken from POP patients during vaginal plastic surgery following colpohysterectomy, and from control patients during closure of the posterior fornix following hysterectomy. Samples were processed for histological and immunohistochemical analyses for Collagen I and Collagen III, α-Smooth Muscle Actin (α-SMA), Platelet-Derived-Growth-Factor (PDGF), matrix metalloproteinase 3 (MMP3), tissue inhibitors metalloproteinase 1 (TIMP1), Caspase3. Immunofluorescence analyses for Collagen I and III and PDGF were also carried out. In prolapsed specimens our results show a disorganization of smooth muscle cells that appeared to have been displaced by an increased collagen III deposition resulting in rearrangement of the muscularis propria architecture. These findings suggest that the increase in the expression of collagen fibers in muscularis could probably be due to a phenotypic switch resulting in the dedifferentiation of smooth muscle cells into myofibroblasts. These alterations could be responsible for the compromising of the dynamic functionality of the pelvic floor.Key words: Pelvic organ prolapse, immunohistochemistry, smooth muscle cells, collagen, PDGF 相似文献
220.
Plant regeneration from seeds responds to phylogenetic relatedness and local adaptation in Mediterranean Romulea (Iridaceae) species
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Seed germination is the most important transitional event between early stages in the life cycle of spermatophytes and understanding it is crucial to understand plant adaptation and evolution. However, so far seed germination of phylogenetically closely related species has been poorly investigated. To test the hypothises that phylogenetically related plant species have similar seed ecophysiological traits thereby reflecting certain habitat conditions as a result of local adaptation , we studied seed dormancy and germination in seven Mediterranean species in the genus Romulea (Iridaceae). Both the across‐species model and the model accounting for shared evolutionary history showed that cool temperatures (≤ 15°C) were the main factor that promoted seed germination. The absence of embryo growth before radicle emergence is consistent with a prompt germination response at cool temperatures. The range of temperature conditions for germination became wider after a period of warm stratification, denoting a weak primary dormancy. Altogether these results indicate that the studied species exhibit a Mediterranean germination syndrome, but with species‐specific germination requirements clustered in a way that follows the phylogenetic relatedness among those species. In addition, species with heavier seeds from humid habitats showed a wider range of conditions for germination at dispersal time than species from dry habitats possessing lighter seeds. We conclude that while phylogenetically related species showed very similar germination requirements, there are subtle ecologically meaningful differences, confirming the onset of adaptation to local ecological factors mediated by species relatedness. 相似文献