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排序方式: 共有438条查询结果,搜索用时 152 毫秒
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Tiago Turnes Amadeo Félix Salvador Felipe Domingos Lisb?a Rafael Alves de Aguiar Rogério Santos de Oliveira Cruz Fabrizio Caputo 《PloS one》2014,9(10)
The focus of the present study was to investigate the effects of a fast-start pacing strategy on running performance and pulmonary oxygen uptake () kinetics at the upper boundary of the severe-intensity domain. Eleven active male participants (28±10 years, 70±5 kg, 176±6 cm, 57±4 mL/kg/min) visited the laboratory for a series of tests that were performed until exhaustion: 1) an incremental test; 2) three laboratory test sessions performed at 95, 100 and 110% of the maximal aerobic speed; 3) two to four constant speed tests for the determination of the highest constant speed (HS) that still allowed achieving maximal oxygen uptake; and 4) an exercise based on the HS using a higher initial speed followed by a subsequent decrease. To predict equalized performance values for the constant pace, the relationship between time and distance/speed through log-log modelling was used. When a fast-start was utilized, subjects were able to cover a greater distance in a performance of similar duration in comparison with a constant-pace performance (constant pace: 670 m±22%; fast-start: 683 m±22%; P = 0.029); subjects also demonstrated a higher exercise tolerance at a similar average speed when compared with constant-pace performance (constant pace: 114 s±30%; fast-start: 125 s±26%; P = 0.037). Moreover, the mean response time was reduced after a fast start (constant pace: 22.2 s±28%; fast-start: 19.3 s±29%; P = 0.025). In conclusion, middle-distance running performances with a duration of 2–3 min are improved and response time is faster when a fast-start is adopted. 相似文献
3.
Leonardo Magno Rambo Leandro Rodrigo Ribeiro Iuri Domingues Della-Pace Daniel Neis Stamm Rogério da Rosa Gerbatin Marina Prigol Simone Pinton Cristina Wayne Nogueira Ana Flávia Furian Mauro Schneider Oliveira Michele Rechia Fighera Luiz Fernando Freire Royes 《Amino acids》2013,44(3):857-868
A growing body of evidence indicates that creatine (Cr) exerts beneficial effects on a variety of pathologies where energy metabolism and oxidative stress play an etiological role. However, the benefits of Cr treatment for epileptics are still shrouded in controversy. In the present study, we found that acute Cr treatment (300 mg/kg, p.o.) prevented the increase in electroencephalographic wave amplitude typically elicited by PTZ (30, 45 or 60 mg/kg, i.p.). Cr treatment also increased the latency periods of first myoclonic jerks, lengthened the latency periods of the generalized tonic–clonic seizures and reduced the time spent in the generalized tonic–clonic seizures induced by PTZ (60 mg/kg). Administration of PTZ (all doses) decreased Na+, K+-ATPase activity as well as adenosine triphosphate (ATP) and adenosine diphosphate levels in the cerebral cortex, but Cr treatment prevented these effects. Cr administration also prevented increases in xanthine oxidase activity, adenosine monophosphate levels, adenosine levels, inosine levels and uric acid levels that normally occur after PTZ treatment (60 mg/kg, i.p.). We also showed that Cr treatment increased the total Cr (Cr + PCr) content, creatine kinase activity and the mitochondrial membrane potential (ΔΨ) in the cerebral cortex. In addition, Cr prevented PTZ-induced mitochondrial dysfunction characterized by decreasing ΔΨ, increasing thiobarbituric acid-reactive substance levels and increasing protein carbonylation. These experimental findings reinforce the idea that mitochondrial dysfunction plays a critical role in models of epileptic seizures and suggest that buffering brain energy levels through Cr treatment may be a promising therapeutic approach for the treatment of this neurological disease. 相似文献
4.
Fernanda Fai?o-Flores Paulo Rogério Pinto Coelho Jo?o Dias Toledo Arruda-Neto Silvya Stuchi Maria-Engler Manoela Tiago Vera Luiza Capelozzi Ricardo Rodrigues Giorgi Durvanei Augusto Maria 《PloS one》2013,8(3)
Boron neutron capture therapy (BNCT) is a binary treatment involving selective accumulation of boron carriers in a tumor followed by irradiation with a thermal or epithermal neutron beam. The neutron capture reaction with a boron-10 nucleus yields high linear energy transfer (LET) particles, alpha and 7Li, with a range of 5 to 9 µm. These particles can only travel very short distances and release their damaging energy directly into the cells containing the boron compound. We aimed to evaluate proliferation, apoptosis and extracellular matrix (ECM) modifications of B16F10 melanoma and normal human melanocytes after BNCT. The amounts of soluble collagen and Hsp47, indicating collagen synthesis in the ECM, as well as the cellular markers of apoptosis, were investigated. BNCT decreased proliferation, altered the ECM by decreasing collagen synthesis and induced apoptosis by regulating Bcl-2/Bax in melanoma. Additionally, BNCT also increased the levels of TNF receptor and the cleaved caspases 3, 7, 8 and 9 in melanoma. These results suggest that multiple pathways related to cell death and cell cycle arrest are involved in the treatment of melanoma by BNCT. 相似文献
5.
Diego Ribeiro Migueis Ortega Roberto Hiroaki Nagahama Paulo Cesar Motta Rogério Bertani 《ZooKeys》2013,(352):93-116
The mygalomorph neotropical genus Fufius Simon, 1888 comprises ten species, distributed from Guatemala in Central America to southeastern Brazil, in South America. Most of the species were described from northern South America, in the Amazonian region. Only F. funebris Vellard, 1924 and F. lucasae Guadanucci & Indicatti, 2004 are known from regions more to the south of the continent. Herein we describe three new Brazilian species, Fufius minusculus
sp. n. and F. jalapensis
sp. n. from the state of Tocantins, and F. candango
sp. n. from Distrito Federal. The female of F. lucasae is described for first time and the male and female of F. funebris are redescribed based on specimens collected at the type locality. 相似文献
6.
Guilherme Loss-Morais Andreia Carina Turchetto-Zolet Matheus Etges Alexandro Cagliari Ana Paula K?rbes Felipe dos Santos Maraschin Márcia Margis-Pinheiro Rogério Margis 《Genetics and molecular biology》2013,36(1):74-86
Ribosome-inactivating proteins (RIPs) are enzymes that inhibit protein synthesis after depurination of a specific adenine in rRNA. The RIP family members are classified as type I RIPs that contain an RNA-N-glycosidase domain and type II RIPs that contain a lectin domain (B chain) in addition to the glycosidase domain (A chain). In this work, we identified 30 new plant RIPs and characterized 18 Ricinus communis RIPs. Phylogenetic and functional divergence analyses indicated that the emergence of type I and II RIPs probably occurred before the monocot/eudicot split. We also report the expression profiles of 18 castor bean genes, including those for ricin and agglutinin, in five seed stages as assessed by quantitative PCR. Ricin and agglutinin were the most expressed RIPs in developing seeds although eight other RIPs were also expressed. All of the RIP genes were most highly expressed in the stages in which the endosperm was fully expanded. Although the reason for the large expansion of RIP genes in castor beans remains to be established, the differential expression patterns of the type I and type II members reinforce the existence of biological functions other than defense against predators and herbivory. 相似文献
7.
Gilson Stanski Alícia Giolo Hippólito Rogério C. Costa Antonio L. Castilho 《Invertebrate reproduction & development.》2019,63(1):67-75
We aimed to study the fecundity and reproductive investment of Loxopagurus loxochelis under different environmental conditions. In total, 67 ovigerous females were analyzed, 20 from Macaé, 26 from Ubatuba and 21 from Cananéia. The cephalothoracic shield length, fecundity and reproductive investment (Ubatuba 10.2%, Macaé 8.9% and Cananéia 7.5%) were different among the regions (ANCOVA, p < 0.05), caused by different abiotic resources and environmental characteristics found in each sampling region. Cananéia had the smallest individuals and low availability of adequate shells to hermit crabs, a condition that may have affected the growth and reproduction of the animals. Macaé has a continuous transport of nutrients such as nitrogen and phosphorus to the surface promoted by the Cabo Frio Upwelling zone, which may be a favourable condition for plankton production and, consequently, the extended ‘match/mismatch’ adjustment of spawning females of L. loxochelis. We propose that the highest reproductive investment on the Ubatuba coast is a consequence of regional environmental scenarios of waters colder than the Cananéia region, i.e. females concentrate more energy to reproduce seasonally. Thus, we proved that patterns of L. loxochelis’ reproduction can change on a regional scale according to the local condition of shell supply and water temperature. 相似文献
8.
Alexander S. de Resende Rogério P. Xavier Octávio C. de Oliveira Segundo Urquiaga Bruno J. R. Alves Robert M. Boddey 《Plant and Soil》2006,281(1-2):339-351
Since the 1970s the area under sugarcane in Brazil has increased from 2 million to over 5 million ha (M ha), and it is expected
to pass the 7 M ha mark in 2007. More than half of the cane is harvested to produce bioethanol as a fuel for light vehicles.
The distilleries produce approximately 13 L of distillery waste (vinasse) for each litre of ethanol produced. In the 1980s
there was considerable concern over the long-term effects of the disposal of this material (containing about 1% carbon and
high in K) on cane yields if it was applied to the field. At the same time there was a growing movement to abandon the practice
of pre-harvest burning and some research was showing that some Brazilian varieties of sugar cane were able to obtain significant
contributions of N from plant-associated biological nitrogen fixation (BNF). For these reasons an experiment was installed
on a cane plantation in the state of Pernambuco, NE Brazil to investigate the long-term effects of vinasse and N fertiliser
additions and the practice of pre-harvest burning on crop and sugar yield, soil fertility parameters, N balance and soil C
stocks. The results showed that over a 16-year period, trash conservation (abandonment of burning) increased cane yields by
25% from a mean of 46 to 58 Mg ha−1. Vinasse applications (80 m3 ha−1 crop−1) increased mean cane and sugar yield by 12 to 13% and the application of 80 kg N ha−1 as urea increased cane yields by 9%, but total sugar yield by less than 6% (from 7.0 to 7.4 Mg ha−1 crop−1). The total N balance for the soil/plant system when only the surface 20 cm of the soil was considered was positive in plots
where no N fertiliser was added. However, the data indicated that during the 16 years of the study considerable quantities
of soil organic matter were accumulated below 20 cm depth such that the N balance considering the soil to 60 cm depth was
strongly positive, except where N fertiliser was added. The data indicated that there were considerable BNF inputs to the
system, which was consistent with its low response to N fertiliser and low N fertiliser-use-efficiency. There were no significant
effects of vinasse or urea addition, or trash conservation on soil C stocks, although the higher yields proportioned by trash
conservation had potentially significant benefits for increased mitigation of CO2 emissions where the main use of the cane was for bioethanol production. 相似文献
9.
Maicon S. N. dos Santos João H. C. Wancura Carolina E. D. Oro Rogério M. Dallago Marcus V. Tres 《Phyton》2022,91(6):1105-1127
The growing development of biological products highlights the social and environmental responsibility that several industrial companies are facing in recent years. In this context, the advancement of bioprocessing as an alternative for exploring the potential of ecologically based products, especially in biofuels, food, and agro-industrial business, exposes the rational efficiency of the application of renewable sources in different industrial segments. Industries strongly associated with food production concentrate large amounts of wastes rich in bioactive compounds. A range of highly effective technologies has been highly explored to recover large concentrations of prominent compounds present in these materials. The advances in this scenario assurance value addition to these by-products, in addition to highlighting their various technological applications, considering the biorefinery and ecologically based production concepts. Accordingly, this review article described a detailed and systematic approach to the importance of using bioactive compounds and exploring the main sources of these elements. Also, some recent and innovative research that has achieved encouraging results was highlighted. Furthermore, the study included the main extraction technologies that have been investigated as a strategy of prospecting the application of bioactive compounds and optimizing the processes for obtaining natural compounds from plant sources. Finally, future outlooks were presented to contribute to the innovative opportunities and applicability of highly promising technologies and manipulations of bioactive compounds from a range of perspectives. 相似文献
10.
Maria Cristina Schneider Patricia Najera Martha M. Pereira Gustavo Machado Celso B. dos Anjos Rogério O. Rodrigues Gabriela M. Cavagni Claudia Mu?oz-Zanzi Luis G. Corbellini Mariana Leone Daniel F. Buss Sylvain Aldighieri Marcos A. Espinal 《PLoS neglected tropical diseases》2015,9(11)