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101.
Role of hydrogen peroxide and oxidative stress in healing responses 总被引:11,自引:0,他引:11
Rojkind M Domínguez-Rosales JA Nieto N Greenwel P 《Cellular and molecular life sciences : CMLS》2002,59(11):1872-1891
102.
Our understanding of how immune responses are generated and regulated drives the design of possible immunotherapies for cancer
patients. For that reason, we first describe briefly the actual immunological theories and their common perspectives about
cancer vaccine development. Second, we describe cancer vaccines that are able to induce tumor-specific immune responses in
cancer patients. However, these responses are not always followed by tumor rejection. At the end of the review, we discuss
two possible reasons that might explain this dichotomy of cancer immunology. First, the immune response generated, although
detectable, may not be quantitatively sufficient to reject the tumor. Second, the tumor microenvironment may modulate tumor
cell susceptibility to the systemic immune response induced by the immunization. Finally, we discuss what, in our opinion,
might be the best way to improve cancer vaccine strategies and how the relationship between the tumor and its surroundings
might be studied in more details.
Received 21 June 2001; received after revision 15 August 2001; accepted 15 August 2001 相似文献
103.
Recombinational DNA double-strand breaks in mice precede synapsis 总被引:24,自引:0,他引:24
Mahadevaiah SK Turner JM Baudat F Rogakou EP de Boer P Blanco-Rodríguez J Jasin M Keeney S Bonner WM Burgoyne PS 《Nature genetics》2001,27(3):271-276
In Saccharomyces cerevisiae, meiotic recombination is initiated by Spo11-dependent double-strand breaks (DSBs), a process that precedes homologous synapsis. Here we use an antibody specific for a phosphorylated histone (gamma-H2AX, which marks the sites of DSBs) to investigate the timing, distribution and Spo11-dependence of meiotic DSBs in the mouse. We show that, as in yeast, recombination in the mouse is initiated by Spo11-dependent DSBs that form during leptotene. Loss of gamma-H2AX staining (which in irradiated somatic cells is temporally linked with DSB repair) is temporally and spatially correlated with synapsis, even when this synapsis is 'non-homologous'. 相似文献
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105.
Penkowa M Espejo C Martínez-Cáceres EM Montalban X Hidalgo J 《Cellular and molecular life sciences : CMLS》2003,60(1):185-197
Metallothioneins I+II (MT-I+II) are antioxidant, neuroprotective factors. We previously showed that MT-I+II deficiency during
experimental autoimmune encephalomyelitis (EAE) leads to increased disease incidence and clinical symptoms. Moreover, the
inflammatory response of macrophages and T cells, oxidative stress, and apoptotic cell death during EAE were increased by
MT-I+II deficiency. We now show for the first time that demyelination and axonal damage are significantly increased in MT-I+II
deficient mice during EAE. Furthermore, oligodendroglial regeneration, growth cone formation, and tissue repair including
expression of trophic factors were significantly reduced in MT-I+II-deficient mice during EAE. Accordingly, MT-I+II have protective
and regenerative roles in the brain.
Received 31 October 2002; received after revision 23 November 2002; accepted 26 November 2002
RID="*"
ID="*"Corresponding author. M. Penkowa and C. Espejo contributed equally to this paper. 相似文献
106.
Large Cretaceous sphenodontian from Patagonia provides insight into lepidosaur evolution in Gondwana
Sphenodontian reptiles successfully radiated during Triassic and Jurassic times, but were driven almost to extinction during the Cretaceous period. The sparse Early Cretaceous record of sphenodontians has been interpreted as reflecting the decline of the group in favour of lizards, their suspected ecological successors. However, recent discoveries in Late Cretaceous beds in Patagonia partially modify this interpretation. Numerous skeletons of a new sphenodontian, Priosphenodon avelasi gen. et sp. nov., were collected from a single locality in the Cenomanian-Turonian Candeleros Formation, where it is more abundant than any other tetrapod group recorded in the quarry (for example, Crocodyliformes, Serpentes, Dinosauria and Mammalia). Adult specimens of Priosphenodon reached one metre in length, larger than any previously known terrestrial sphenodontian. Here we propose, using available evidence, that sphenodontians were not a minor component of the Cretaceous terrestrial ecosystems of South America, and that their ecological replacement by squamates was delayed until the early Tertiary. The new discovery helps to bridge the considerable gap in the fossil record (around 120 million years) that separates the Early Cretaceous sphenodontians from their living relatives (Sphenodon). 相似文献
107.
108.
Samuel Sarmiento Juan Manuel García-Manso Juan Manuel Martín-González Diana Vaamonde Javier Calderón Marzo Edir Da Silva-Grigoletto 《系统科学与复杂性》2013,26(1):104-116
The aim of this paper is to describe and analyse the behaviour of heart rate variability (HRV) during constant-load, high-intensity exercise using a time frequency analysis (Wavelet Transform). Eleven elite cyclists took part in the study (age: 18.6±3.0 years; VO2max: 4.88±0.61 litres·min?1). Initially, all subjects performed an incremental cycloergometer test to determine load power in a constant load-test (379.55±36.02 W; 89.0%). HRV declined dramatically from the start of testing (p <0.05). The behaviour of power spectral density within the LF band mirrored that of total energy, recording a significant decrease from the outset LF peaks fell rapidly thereafter, remaining stable until the end of the test. HF-VHF fell sharply in the first 20 to 30 seconds. The relative weighting (%) of HF-VHF was inverted with the onset of fatigue, [1.6% at the start, 7.1 (p <0.05) at the end of the first phase, and 43.1% (p <0.05) at the end of the test]. HF-VHFpeak displayed three phases: a moderate initial increase, followed by a slight fall, thereafter increasing to the end of the test. The LF/HF-VHF ratio increased at the start, later falling progressively until the end of the first phase and remaining around minimal values until the end of the test. 相似文献
109.
110.