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排序方式: 共有5849条查询结果,搜索用时 375 毫秒
941.
942.
Heiman F. L. Wertheim Huyen Nguyen Nguyen Walter Taylor Trinh Thi Minh Lien Hoa Thi Ngo Thai Quoc Nguyen Bich Ngoc Thi Nguyen Ha Hong Nguyen Ha Minh Nguyen Cap Trung Nguyen Trinh Tuyet Dao Trung Vu Nguyen Annette Fox Jeremy Farrar Constance Schultsz Hien Duc Nguyen Kinh Van Nguyen Peter Horby 《PloS one》2009,4(6)
Background
Streptococcus suis can cause severe systemic infection in adults exposed to infected pigs or after consumption of undercooked pig products. S. suis is often misdiagnosed, due to lack of awareness and improper testing. Here we report the first fifty cases diagnosed with S. suis infection in northern Viet Nam.Methodology/Principal Findings
In 2007, diagnostics for S. suis were set up at a national hospital in Hanoi. That year there were 43 S. suis positive cerebrospinal fluid samples, of which S. suis could be cultured in 32 cases and 11 cases were only positive by PCR. Seven patients were blood culture positive for S. suis but CSF culture and PCR negative; making a total of 50 patients with laboratory confirmed S. suis infection in 2007. The number of S. suis cases peaked during the warmer months.Conclusions/Significance
S. suis was commonly diagnosed as a cause of bacterial meningitis in adults in northern Viet Nam. In countries where there is intense and widespread exposure of humans to pigs, S. suis can be an important human pathogen. 相似文献943.
Jason A. L. Jeffery Nguyen Thi Yen Vu Sinh Nam Le Trung Nghia Ary A. Hoffmann Brian H. Kay Peter A. Ryan 《PLoS neglected tropical diseases》2009,3(11)
Background
A life-shortening strain of the obligate intracellular bacteria Wolbachia, called wMelPop, is seen as a promising new tool for the control of Aedes aegypti. However, developing a vector control strategy based on the release of mosquitoes transinfected with wMelPop requires detailed knowledge of the demographics of the target population.Methodology/Principal Findings
In Tri Nguyen village (611 households) on Hon Mieu Island in central Vietnam, we conducted nine quantitative entomologic surveys over 14 months to determine if Ae. aegypti populations were spatially and temporally homogenous, and to estimate population size. There was no obvious relationship between mosquito (larval, pupal or adult) abundance and temperature and rainfall, and no area of the village supported consistently high numbers of mosquitoes. In almost all surveys, key premises produced high numbers of Ae. aegypti. However, these premises were not consistent between surveys. For an intervention based on a single release of wMelPop-infected Ae. aegypti, release ratios of infected to uninfected adult mosquitoes of all age classes are estimated to be 1.8–6.7∶1 for gravid females (and similarly aged males) or teneral adults, respectively. We calculated that adult female mosquito abundance in Tri Nguyen village could range from 1.1 to 43.3 individuals of all age classes per house. Thus, an intervention could require the release of 2–78 wMelPop-infected gravid females and similarly aged males per house, or 7–290 infected teneral female and male mosquitoes per house.Conclusions/Significance
Given the variability we encountered, this study highlights the importance of multiple entomologic surveys when evaluating the spatial structure of a vector population or estimating population size. If a single release of wMelPop-infected Ae. aegypti were to occur when wild Ae. aegypti abundance was at its maximum, a preintervention control program would be necessary to ensure that there was no net increase in mosquito numbers. However, because of the short-term temporal heterogeneity, the inconsistent spatial structure and the impact of transient key premises that we observed, the feasibility of multiple releases of smaller numbers of mosquitoes also needs to be considered. In either case, fewer wMelPop-infected mosquitoes would then need to be released, which will likely be more acceptable to householders. 相似文献944.
Doan Van-Thuoc Héctor Guzmán Mai Thi-Hang Rajni Hatti-Kaul 《Marine biotechnology (New York, N.Y.)》2010,12(5):586-593
Two cultivation steps were used for production of biomass and ectoine by Halomonas boliviensis, respectively. The optimization of some nutrient parameters in each step was investigated by using response surface methodology.
Twenty and 12 experiments were performed to attain optimal conditions for biomass and ectoine production, respectively. The
model predicted a maximum biomass concentration of 3.34 g/L on optimization of NH4Cl, K2HPO4, and MgSO4•7H2O concentrations during the first cultivation, while a maximum ectoine concentration of 1.27 g/L was predicted on optimizing
NaCl and monosodium glutamate concentrations in the second cultivation. The experimental values obtained (3.36 g biomass/L
and 1.25 g ectoine/L) were in good agreement with the predicted values. The optimized conditions were also used for two-step
1.5-L fed-batch fermentations. In the first step, biomass concentration of 28.7 g/L was obtained while in the second step
biomass concentration increased to 63 g/L. Ectoine concentration of 9.2 g/L was obtained, and the overall ectoine productivity
was 6.3 g/L/day, being among the highest reported so far. 相似文献
945.
Seon-Ah Ha Hyun K Kim JinAh Yoo SangHee Kim Seung M Shin Youn S Lee Soo Y Hur Yong W Kim Tae E Kim Yeun J Chung Shin S Jeun Dong W Kim Yong G Park Jin Kim Soon Y Shin Young H Lee Jin W Kim 《BMC cell biology》2010,11(1):1-9
Background
Cell transdifferentiation is characterized by loss of some phenotypes along with acquisition of new phenotypes in differentiated cells. The differentiated state of a given cell is not irreversible. It depends on the up- and downregulation exerted by specific molecules.Results
We report here that HCCR-1, previously shown to play an oncogenic role in human cancers, induces epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) in human and mouse, respectively. The stem cell factor receptor CD117/c-Kit was induced in this transdifferentiated (EMT) sarcoma tissues. This MET occurring in HCCR-1 transfected cells is reminiscent of the transdifferentiation process during nephrogenesis. Indeed, expression of HCCR-1 was observed during the embryonic development of the kidney. This suggests that HCCR-1 might be involved in the transdifferentiation process of cancer stem cell.Conclusions
Therefore, we propose that HCCR-1 may be a regulatory factor that stimulates morphogenesis of epithelia or mesenchyme during neoplastic transformation. 相似文献946.
Hans Knecht Silke Brüderlein Silke Wegener Daniel Lichtensztejn Zelda Lichtensztejn Bruno Lemieux Peter Möller Sabine Mai 《BMC cell biology》2010,11(1):99
Background
In cancer cells the three-dimensional (3D) telomere organization of interphase nuclei into a telomeric disk is heavily distorted and aggregates are found. In Hodgkin's lymphoma quantitative FISH (3D Q-FISH) reveals a major impact of nuclear telomere dynamics during the transition form mononuclear Hodgkin (H) to diagnostic multinuclear Reed-Sternberg (RS) cells. In vitro and in vivo formation of RS-cells is associated with the increase of very short telomeres including "t-stumps", telomere loss, telomeric aggregate formation and the generation of "ghost nuclei". 相似文献947.
Analysis of protein interactions on protein arrays by a novel spectral surface plasmon resonance imaging 总被引:4,自引:0,他引:4
Yuk JS Kim HS Jung JW Jung SH Lee SJ Kim WJ Han JA Kim YM Ha KS 《Biosensors & bioelectronics》2006,21(8):1521-1528
We presented a novel surface plasmon resonance (SPR) imaging method for analysis of protein arrays based on a wavelength interrogation-based SPR biosensor. The spectral imaging was performed by the combination of position control and resonance wavelengths calculated from SPR reflectivity spectra. The imaging method was evaluated by analyzing interactions of glutathione S-transferase-fusion proteins with their antibodies. Antigen-antibody interactions were successfully analyzed on glutathione S-transferase-fusion protein arrays by using the spectral imaging method, and the results were confirmed by a parallel analysis using a previously used spectral SPR biosensor based on wavelength interrogation. Specific binding of anti-Rac1 and anti-RhoA to Rac1 and RhoA on the protein arrays was qualitatively and quantitatively analyzed by the spectral SPR imaging. Thus, it was suggested that the novel spectral SPR imaging was a useful tool for the high-throughput analysis of protein-protein interactions on protein arrays. 相似文献
948.
949.
Kim ND Yoon J Kim JH Lee JT Chon YS Hwang MK Ha I Song WJ 《Bioorganic & medicinal chemistry letters》2006,16(14):3772-3776
Mental retardation is the most common and debilitating condition for individuals with Down syndrome (DS). The hyper-activation of DYRK1A by overexpression causes significant learning and memory deficits in DS-model mice. Thus far, no mechanism-based drug has been developed to address this. After a combination of in silico and in vitro screenings, two DYRK1A inhibitors were isolated that are active in a cell-based assay. Further optimization could lead to a novel drug discovery that could address DS learning and memory deficits. 相似文献
950.
Cho SY Baek JY Han SS Kang SK Ha JD Ahn JH Lee JD Kim KR Cheon HG Rhee SD Yang SD Yon GH Pak CS Choi JK 《Bioorganic & medicinal chemistry letters》2006,16(3):499-502
A series of novel cyclopenta[d][1,2]-oxazine derivatives was prepared and evaluated for their inhibitory activity toward protein tyrosine phosphatase 1B (PTP-1B). Compound 6s was found to be an inhibitor of PTP-1B with nanomolar IC(50) value and high level of selectivity over other recombinant phosphatases. 相似文献