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701.
Stature is the most often used anthropometric measure in the nutritional, growth and development, anthropological and forensic oriented studies. Its estimate is considered to be an important assessment in the identification of unknown human remains and its medico-legal significance is obvious in forensic examinations. Diurnal variation in stature is a biological norm in the human body and its effects can be reflected in the reliability of height data in these studies. We hypothesize that the extent of diurnal variation is more in children as compared to adults in a population. 相似文献
702.
G B Castellanos S Menezes J Angluster W De Souza L R Caldas 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1985,47(2):191-195
Herpetomonas samuelpessoai is a non-pathogenic protozoan that shares important antigens with Trypanosoma cruzi (the agent of Chagas' disease) and which shows three developmental stages: promastigote, paramastigote and the highly differentiated form opisthomastigote. Due to the difficulties in obtaining the last form, its physiology and biochemistry are not well understood, and procedures which can induce the process of differentiation promastigote-opisthomastigote are desirable. In this work we show that illumination of H. samuelpessoai with white light in the presence of methylene blue and oxygen (photodynamic effect) triggers the process of differentiation in a very efficient manner (the cultures show up to 70 per cent of the cells in the opisthomastigote form). We also observed that illumination alone and incubation with methylene blue in the dark can trigger the process but in levels markedly lower than illumination in the presence of the dye. 相似文献
703.
J Menezes 《Canadian journal of microbiology》1971,17(2):171-174
704.
Sendai virus envelopes can mediate Epstein-Barr virus binding to and penetration into Epstein-Barr virus receptor-negative cells 总被引:1,自引:0,他引:1 下载免费PDF全文
Epstein-Barr virus (EBV) receptor-negative cells were treated with UV-inactivated Sendai virus (SV) or with reconstituted SV envelopes having a low hemolytic activity and then assayed for EBV binding or for susceptibility to EBV infection. EBV binding was assessed by using both unlabeled and fluoresceinated EBV preparations. It was found that SV or SV envelope treatment renders these cells able to bind EBV. Various experiments were performed to clarify the mechanism of this SV-induced binding. The EBV receptor-negative 1301 cells were treated with SV either at 0°C or at both 0 and 37°C successively and then examined for EBV binding at 0°C. It was thus found that when SV treatment was performed exclusively at 0°C, the target cells showed higher fluorescence intensity after their incubation with fluoresceinated EBV. In addition, Clostridium perfringens neuraminidase treatment of 1301 cells did not induce any EBV binding to these cells. These data indicate that EBV binding is not due to the disturbance of the cell membrane by SV envelope fusion or to the uncovering of EBV binding sites on the cells after the enzymatic action of SV neuraminidase. Moreover, bound EBV was partly eluted from SV-treated 1301 cells at 37°C, and the treatment of EBV with C. perfringens neuraminidase inhibited its SV-mediated binding. These data indicate that EBV binds to the hemagglutinin-neuraminidase of SV on the target cell surface and that a fraction of the bound EBV becomes irreversibly associated with the SV-treated cell membrane. Our data also show that EBV can penetrate into 1301 cells which have incorporated SV envelopes into their membrane, as demonstrated by the induction of the EBV-determined nuclear antigen by B95-8 EBV in SV envelope-treated 1301 cells. 相似文献
705.
Luiz Fernando Wurdig Roesch Roberta R. Fulthorpe Rodrigo Josemar Seminoti Jaccques Fátima Menezes Bento Flávio Anastácio de Oliveira Camargo 《World journal of microbiology & biotechnology》2010,26(8):1503-1508
This study evaluated diazotrophic bacterial diversity of soils from four different sites in South and North America. Approximately
one hundred and thirty-nine thousand partial sequences of the small subunit of the bacterial ribosomal RNA gene generated
for a previous study were used for this work. Sequences that presented at least 90% similarity with known diazotrophic organisms
were pulled from the original dataset and a new library containing 14,842 sequences from nitrogen-fixing bacteria were analysed.
The number of sequences and the abundance of identifiable/cultivable diazotrophic genera were used for the calculation of
the Shannon–Weaver diversity index and Evenness. All soils exhibited similar diazotrophic diversity, illustrating the great
amount of similarity found between randomly chosen soils. Out of 81 diazotrophic genera, 45 were found in common in the four
soils tested irrespective of the localization or cultivation. The degree of dominance of these common genera within their
communties differed widely between soils. Sixteen types were found in only one sample. 相似文献
706.
707.
Pronounced seasonal and daily oxygen concentration changes are characteristic for Amazonian floodplain lakes. Studies on the fish fauna of the Lago Camaleão, Solimões River, Amazonas, Brazil, showed several fish species which are able to survive prolonged periods of heavy hypoxia. Twenty species belonging to eight families were observed in the laboratory in order to determine their respiratory adaptations to hypoxic conditions and oxygen concentrations at which the fish present respiratory adaptations. Finally, the fish species were distributed throughout the habitats of Lake Camaleão according to their adaptation responses. Ten fish species used the surface water for aquatic surface respiration, four species used atmospheric oxygen for aerial respiration, four species used oxygen supplied by the exudation of the roots of floating macrophytes and two exhibited a high tolerance to hypoxic conditions, and well-developed physiological biochemical mechanisms. The fish fauna is well adapted to low oxygen concentrations. The large variety of morpho-anatomical adaptations associated with biochemical and physiological mechanisms to tolerate hypoxic and anoxic conditions enable the 20 fish species to exploit several habitats of Lago Camaleão, such as floating aquatic macrophyte meadows, open water and near the shoreline. 相似文献
708.
Genetic relationships among five nemipterid fish species from the Indian coast using allozyme analysis 总被引:1,自引:0,他引:1
Based on Nei's genetic distance Nemipterus peronii and Nemipterus japonicus showed a greater affinity to Parascolopsis aspinosa than to the other Nemipterus species studied. Significant differences between the Indian west and east coast samples of N. japonicus were detected. Polymorphic (P<0.95) and diagnostic loci suitable for stock delineation and species identification were observed. 相似文献