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1.
Maria Ieda Siqueira Linhares Yoshito Eizuru Gildete Patriota de Andrade Ivailda Barbosa Fonseca Luiz Bezerra Carvalho Ivanildo Tenorio Moreira Yoichi Minamishima 《Microbiology and immunology》1994,38(6):475-478
The seroprevalence of human T cell leukemia virus type 1 (HTLV-1) infection was investigated in Brazilians (570): native inhabitants (298) and descendants from Japanese (272) living in Recife and its neighborhoods—North-east of Brazil. Furthermore, polytransfused renal transplanted patients (54) were also examined for the serological status to this virus. The seropositivity to HTLV-1, screened by enzyme-linked immunosorbent assay (ELISA), was low: 1.34% for the local population and 0.73% for the descendants from Japanese. However, the seropositivity for the renal transplanted patients was found to be 11.1%. This higher value suggests that this retrovirus infection seems to be of importance in this clinical condition. 相似文献
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The asexual nature of the first cortical reorganization of conjugation in Stylonychia was analyzed by comparing the effect of amputation performed at different stages of early conjugation to that performed on vegetative cells at different stages of the cell cycle. Amputation of vegetative cells delineated a point of commitment to binary fission at 0.51–0.57 of the cell cycle. Cells amputated before this point were induced to undergo the regenerative mode of asexual development, but those amputated after this point continued with binary fission. In parallel, during conjugation a similar commitment was made around the time of formation of tight mating-pairs: early conjugants amputated around this time might undergo regeneration, and those operated on after this stage continued with the first cortical reorganization as in typical conjugants. The two mates of a pair might differ in their response to amputation, suggesting that the timing of commitment to the first cortical reorganization is not related to the events of conjugation, but rather is individually determined in the vegetative cycle of the cells before they pair up in mating. These observations provide support for the notion that the first cortical reorganization of conjugants is homologous to the asexual mode of cortical development in dividers, according to the theory of developmental heterochrony in the sexual reproduction of hypotrichs. The timing of commitment to the first cortical reorganization was found to temporally correlate with the entrance of the micronuclei into meiosis. Since the first cortical reorganization can proceed without the micronucleus, this raises the possibility that initiation of micronuclear meiosis is closely coupled with, and may be determined by, the commitment to the first cortical reorganization. 相似文献
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地塞美松中间体的C1,4脱氢和11α-羟基化 总被引:2,自引:0,他引:2
地塞美松 (Dexamethasone)为高效肾上腺皮质激素药物 ,临床上广泛使用。开拓用梯可吉宁 (Tigogenin)为起始原料生产从化学结构和合成技术上讲较为合理 ,而且适合于资源综合利用[1] 。在合成过程中 ,除了A环需引入C1,2 和C4 ,5两个双键 (含C-3 羟基氧化 )外 ,还需用微生物法在C-11位引入羟基。国外常采用化学法脱氢 ,然后再用霉菌 11α 羟基化[2 ,3 ] 。本文报道用两类微生物菌种 ,节杆菌 (Arthrobactersp .)AX86和绿僵菌 (Metarhiziumsp .)M 88,混合转化一步完成脱氢和羟基化反应… 相似文献
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甾体1,4-脱氢和11α-羟基化反应的两种不同微生物转化 总被引:2,自引:1,他引:2
Two kinds of micro-organism, Arthrobacter sp. AX86(1,4-dehdrogenator)and Absidia sp. A28(11α-hydroxylator) were used in this experiment. Two different fermentation techniques were performed to accomplish the multiple conversional reactions for producing 16β-methyl-11α, 17α, 21-trihydroxy-1,4-pregnadiene-3,20-dione (Ⅲ) from 16β-methyl-3β, 17α,21-trihydroxy-5α-pregnane-20-one-21-acetate(1) 1)To produce product(Ⅲ)by means of a two-step fermentation method which were independently performed first by Arthrobacter and next by Abslaia, and 2)the product was obtained by a sequential fermentation system of aforesaid two micro-organisms in a single fermentor without isolation of the intermediates from the mixture. Our results showed that in both fermentation systems high yield of product was obtained. However, according to the technical simplicity, shorter duration of fermentation cycle and efficient yield of product, the second method is better than the first one. 相似文献
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Koen Peeters Grietens Joan Muela Ribera Veronica Soto Alex Tenorio Sarah Hoibak Angel Rosas Aguirre Elizabeth Toomer Hugo Rodriguez Alejandro Llanos Cuentas Umberto D'Alessandro Dionicia Gamboa Annette Erhart 《PloS one》2013,8(1)
Background
While coverage of long-lasting insecticide-treated nets (LLIN) has steadily increased, a growing number of studies report gaps between net ownership and use. We conducted a mixed-methods social science study assessing the importance of net preference and use after Olyset® LLINs were distributed through a mass campaign in rural communities surrounding Iquitos, the capital city of the Amazonian region of Peru.Methods
The study was conducted in the catchment area of the Paujil and Cahuide Health Centres (San Juan district) between July 2007 and November 2008. During a first qualitative phase, participant observation and in-depth interviews collected information on key determinants for net preference and use. In a second quantitative phase, a survey among recently confirmed malaria patients evaluated the acceptability and use of both LLINs and traditional nets, and a case control study assessed the association between net preference/use and housing structure (open vs. closed houses).Results
A total of 10 communities were selected for the anthropological fieldwork and 228 households participated in the quantitative studies. In the study area, bed nets are considered part of the housing structure and are therefore required to fulfil specific architectural and social functions, such as providing privacy and shelter, which the newly distributed Olyset® LLINs ultimately did not. The LLINs'' failure to meet these criteria could mainly be attributed to their large mesh size, transparency and perceived ineffectiveness to protect against mosquitoes and other insects, resulting in 63.3% of households not using any of the distributed LLINs. Notably, LLIN usage was significantly lower in houses with no interior or exterior walls (35.2%) than in those with walls (73.8%) (OR = 5.2, 95CI [2.2; 12.3], p<0.001).Conclusion
Net preference can interfere with optimal LLIN use. In order to improve the number of effective days of LLIN protection per dollar spent, appropriate quantitative and qualitative methods for collecting information on net preference should be developed before any LLIN procurement decision is made. 相似文献10.
Antonio Jiménez-Escrig Eva Gómez-Ordóñez María Dolores Tenorio Pilar Rupérez 《Journal of applied phycology》2013,25(2):503-512
The edible brown seaweed sugar Kombu (Saccharina latissima) is a good source of dietary fiber (DF) and associated compounds. Besides it presents antioxidant capacity in vitro due to their sulfated polysaccharides and polyphenols. The effect of a DF-rich sugar Kombu diet on biochemical parameters and antioxidant and prebiotic effects in healthy rats was evaluated. Thus, rats were fed either a basal diet or a supplemented one with 10 % sugar Kombu for 4 weeks. Several health-promoting effects were found such as a decrease in triglycerides (TGL) and uric acid (UrA), and an increase in antioxidant status both in serum and cecum. Regarding prebiotic effect, higher cecum weight and total short chain fatty acid (SCFA) content were evidenced in the seaweed-fed group, without significant differences on total bacterial count of feces. Sugar Kombu and sulfated polysaccharides from its DF could be used as functional ingredients for further nutraceutical applications. 相似文献