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91.
Coral Reefs - Both natural and anthropogenic factors are changing coral-reef structure and function worldwide. Long-term monitoring has revealed declines in the local composition and species... 相似文献
92.
Mary H Torres Luz M Salazar Magnolia Vanegas Fanny Guzman Raul Rodriguez Yolanda Silva Jaiver Rosas Manuel E Patarroyo 《European journal of biochemistry》2003,270(19):3946-3952
The merozoite surface protein-1 represents a prime candidate for development of a malaria vaccine. Merozoite surface protein-1 has been shown to demonstrate high-activity peptide binding to human red blood cells. One of the high-activity binding peptides, named 5501, located in the N-terminus (amino acid sequence MLNISQHQCVKKQCPQNS) of the 19-kDa molecular mass fragment of merozoite surface protein-1, is conserved, nonimmunogenic and nonprotective. Its critical binding residues were identified and replaced with amino acids of similar mass but different charge, in order to modify their immunogenic and protective characteristics. Three analogues with positive or negative immunological results were studied by nuclear magnetic resonance to correlate their three-dimensional structure with their biological functions. The studied peptides presented alpha-helical fragments, but in different peptide regions and extensions, except for randomly structured 5501. We show that altering a few amino acids induced immunogenicity and protectivity against experimental malaria and changed the peptide three-dimensional structure, suggesting a better fit with immune-system molecules. 相似文献
93.
Govindan Velu Ravi P. Singh Maria Elena Cardenas Bihua Wu Carlos Guzman Ivan Ortiz-Monasterio 《Acta Physiologiae Plantarum》2017,39(9):212
At least two billion people around the world suffer from micronutrient deficiency, or hidden hunger, which is characterized by iron-deficiency anemia, vitamin A and zinc deficiency. As a key staple food crop, wheat provides 20% of the world’s dietary energy and protein, therefore wheat is an ideal vehicle for biofortification. Developing biofortified wheat varieties with genetically enhanced levels of grain zinc (Zn) and iron (Fe) concentrations, and protein content provides a cost-effective and sustainable solution to the resource-poor wheat consumers. Large genetic variation for Fe and Zn were found in the primitive and wild relatives of wheat, the potential high Zn and Fe containing genetic resources were used as progenitors to breed high-yielding biofortified wheat varieties with 30–40% higher Zn content. Grain protein content (GPC) determines processing and end-use quality of wheat for making diverse food products. The GPC-B1 allele from Triticum turgidum L. var. dicoccoides have been well characterized for the increase in GPC and the associated pleiotropic effect on grain Zn and Fe concentrations in wheat. In this study effect of GPC-B1 allele on grain Zn and Fe concentrations in wheat were measured in different genetic backgrounds and two different agronomic management practices (with- and without foliar Zn fertilization). Six pairs of near-isogenic lines differing for GPC-B1 gene evaluated at CIMMYT, Mexico showed that GPC-B1 influenced marginal increase for grain Zn, Fe concentrations, grain protein content and slight reduction in kernel weight and grain yield. However, the magnitude of GPC and grain Zn and Fe reductions varied depending on the genetic background. Introgression of GPC-B1 functional allele in combination with normal or delayed maturity alleles in the CIMMYT elite wheat germplasm has the potential to improve GPC and grain Zn and Fe concentrations without the negative effect on grain yield due to early senescence and accelerated maturity. 相似文献
94.
Aims: The species identification and antimicrobial resistance profiles were determined for enterococci isolated from Southern California surface and ocean waters. Methods and Results: Species identification was determined for 1413 presumptive Enterococcus isolates from urban runoff, bay, ocean and sewage water samples. The most frequently isolated species were Enterococcus faecalis, Enterococcus faecium, Enterococcus hirae, Enterococcus casseliflavus and Enterococcus mundtii. All five of these species were isolated from ocean and bay water with a frequency ranging from 7% to 36%. Enterococcus casseliflavus was the most frequently isolated species in urban runoff making up 36–65% of isolates while E. faecium was the most frequently isolated species in sewage making up 53–78% of isolates. The similar distribution of species in urban runoff and receiving water suggests that urban runoff may be the source of Enterococcus. No vancomycin or high level gentamycin resistance was detected in E. faecalis and E. faecium isolates. Conclusions: Enterococcus faecalis, E. faecium, E. casseliflavus and E. mundtii are the most commonly isolated Enterococcus species from urban runoff and receiving waters in Southern California. Significance and Impact of the Study: Determination of the Enterococcus species isolated from receiving waters and potential pollution sources may assist in determining the sources of pollution. 相似文献
95.
Background
Non-biological signal (or noise) has been the bane of microarray analysis. Hybridization effects related to probe-sequence composition and DNA dye-probe interactions have been observed in differential methylation hybridization (DMH) microarray experiments as well as other effects inherent to the DMH protocol. 相似文献96.
Omar JM Hamza Mecky IN Matee Mainen J Moshi Elison NM Simon Ferdinand Mugusi Frans HM Mikx Wim H van Palenstein Helderman Antonius JMM Rijs André JAM van der Ven Paul E Verweij 《BMC microbiology》2008,8(1):135
Background
In Tanzania, little is known on the species distribution and antifungal susceptibility profiles of yeast isolates from HIV-infected patients with primary and recurrent oropharyngeal candidiasis. 相似文献97.
Jeanine A Verbunt Henk AM Seelen Feljandro P Ramos Bernard HM Michielsen Wim L Wetzelaer Martine Moennekens 《BMC neurology》2008,8(1):7
Background
Over 50% of patients with upper limb paresis resulting from stroke face long-term impaired arm function and ensuing disability in daily life. Unfortunately, the number of effective treatments aimed at improving arm function due to stroke is still low. This study aims to evaluate a new therapy for improving arm function in sub-acute stroke patients based on mental practice theories and functional task-oriented training, and to study the predictors for a positive treatment result. It is hypothesized that a six-week, mental practice-based training program (additional to regular therapy) targeting the specific upper extremity skills important to the individual patient will significantly improve both arm function and daily activity performance, as well as being cost effective. 相似文献98.
Emily HM Wong David K Smith Raul Rabadan Malik Peiris Leo LM Poon 《BMC evolutionary biology》2010,10(1):253
Background
The influenza A virus is an important infectious cause of morbidity and mortality in humans and was responsible for 3 pandemics in the 20th century. As the replication of the influenza virus is based on its host's machinery, codon usage of its viral genes might be subject to host selection pressures, especially after interspecies transmission. A better understanding of viral evolution and host adaptive responses might help control this disease. 相似文献99.
Reiter LA Freeman-Cook KD Jones CS Martinelli GJ Antipas AS Berliner MA Datta K Downs JT Eskra JD Forman MD Greer EM Guzman R Hardink JR Janat F Keene NF Laird ER Liras JL Lopresti-Morrow LL Mitchell PG Pandit J Robertson D Sperger D Vaughn-Bowser ML Waller DM Yocum SA 《Bioorganic & medicinal chemistry letters》2006,16(22):5822-5826
Using SAR from two related series of pyrimidinetrione-based inhibitors, compounds with potent MMP-13 inhibition and >100-fold selectivity against other MMPs have been identified. Despite high molecular weights, clogPs, and polar surface areas, the compounds are generally well absorbed and have excellent pharmacokinetic (PK) properties when dosed as sodium salts. In a rat fibrosis model, a compound from the series displayed no fibrosis at exposures many fold greater than its MMP-13 IC50. 相似文献
100.