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991.
Z. Kato Seiji Fukuda Shunji Tomatsu Hugo Vega Teruo Yasunaga Atsushi Yamagishi Naoto Yamada A. Valencia Luis Alejandro Barrera Kazuko Sukegawa Tadao Orii Naomi Kondo 《Human genetics》1997,101(1):97-101
Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive lysosomal storage disorder caused by a genetic defect in N-acetylgalactosamine-6-sulfate
sulfatase (GALNS). In previous studies, we have found two common mutations in Caucasians and Japanese, respectively. To characterize
the mutational spectrum in various ethnic groups, mutations in the GALNS gene in Colombian MPS IVA patients were investigated,
and genetic backgrounds were extensively analyzed to identify racial origin, based on mitochondrial DNA (mtDNA) lineages.
Three novel missense mutations never identified previously in other populations and found in 16 out of 19 Colombian MPS IVA
unrelated alleles account for 84.2% of the alleles in this study. The G301C and S162F mutations account for 68.4% and 10.5%
of mutations, respectively, whereas the remaining F69V is limited to a single allele. The skewed prevalence of G301C in only
Colombian patients and haplotype analysis by restriction fragment length polymorphisms in the GALNS gene suggest that G301C
originated from a common ancestor. Investigation of the genetic background by means of mtDNA lineages indicate that all our
patients are probably of native American descent.
Received: 2 January 1997 / Accepted: 10 June 1997 相似文献
992.
Jorma Arpalahti Rainer Käppi Pejtti Lehikoinen Harri Lönnberg 《Nucleosides, nucleotides & nucleic acids》2013,32(3):447-448
Abstract Combined UV- and liquid scintillation-HPLC has been applied to study the complexing of purine nucleosides with Pt(II)-diamine ions, and the effect of the complex formation on the acidic depurination. 相似文献
993.
Mono- and sesqui-terpenes of individual oil glands of Citrus latipes fruits were analyzed for their homogeneity. The effect of oleocellosis, desiccation, Penicillium and Phytophthora infection upon the individual terpene components was investigated and expressed in a discriminant analysis and in canonical variables. Each oil gland contained the entire spectrum of terpenes specific for each species, and the biggest difference in affected glands was due to Penicillium infection. 相似文献
994.
Graph coloring—also known as vertex coloring—considers the problem of assigning colors to the nodes of a graph such that adjacent nodes do not share the same color. The optimization version of the problem concerns the minimization of the number of colors used. In this paper we deal with the problem of finding valid graphs colorings in a distributed way, that is, by means of an algorithm that only uses local information for deciding the color of the nodes. The algorithm proposed in this paper is inspired by the calling behavior of Japanese tree frogs. Male frogs use their calls to attract females. Interestingly, groups of males that are located near each other desynchronize their calls. This is because female frogs are only able to correctly localize male frogs when their calls are not too close in time. The proposed algorithm makes use of this desynchronization behavior for the assignment of different colors to neighboring nodes. We experimentally show that our algorithm is very competitive with the current state of the art, using different sets of problem instances and comparing to one of the most competitive algorithms from the literature. 相似文献
995.
Petra Dietrich Rainer Hedrich 《The Plant journal : for cell and molecular biology》1998,15(4):479-487
GCAC1 is a strongly voltage-dependent anion channel in the guard-cell plasma membrane of Vicia faba . In patch–clamp experiments, we have investigated the permeation and gating properties of GCAC1 with respect to its anion dependence in the whole-cell and excised-patch configuration. The relative permeability followed the order SCN– > NO3– > Br– > Cl–, while the single-channel conductances in symmetrical anionic solutions exhibited a nearly inverse sequence. The Cl– dependence of inward currents (Cl– release) is characterized by a maximum single-channel conductance of 89 pS half-saturating at 87 mM cytoplasmic chloride. In addition to this substrate saturation, anion release was also dependent on the external Cl– activity ( K m = 16 mM). In the presence of SCN– and Cl–, the single-channel conductance exhibited an anomalous mole-fraction dependence, identifying GCAC1 as a multi-ion single-file pore. Using anions with increasing ionic size, a minimum pore diameter of 0.5 nm was assumed from their relative permeabilities. In line with an anion-selective channel, a tenfold increase in the extracellular anion activity shifted the reversal potential by –59.8 mV. Simultaneously, the half-activation potential shifted negatively by about 23 mV. A further analysis of the anion dependence revealed that extracellular rather than cytosolic anions affect the gating process of GCAC1. From anion substitution experiments, we conclude that anion concentration and species determines both permeation and gating of the plant anion channel GCAC1. 相似文献
996.
Jose Luis Lopez Guerra Nicolas Isa Michelle M. Kim Celine Bourgier Hugo Marsiglia 《Reports of Practical Oncology and Radiotherapy》2012,17(5):251-254
AimTo assess the role of the young radiation oncologist in the context of important recent advancements in the field of radiation oncology, and to explore new perspectives and competencies of the young radiation oncologist.BackgroundRadiation oncology is a field that has rapidly advanced over the last century. It holds a rich tradition of clinical care and evidence-based practice, and more recently has advanced with revolutionary innovations in technology and computer science, as well as pharmacology and molecular biology.Materials and methodsSeveral young radiation oncologists from different countries evaluated the current status and future directions of radiation oncology.ResultsFor young radiation oncologists, it is important to reflect on the current practice and future directions of the specialty as it relates to the role of the radiation oncologist in the comprehensive management of cancer patients. Radiation oncologists are responsible for the radiation treatment provided to patients and its subsequent impact on patients’ quality of life. Young radiation oncologists must proactively master new clinical, biological and technical information, as well as lead radiation oncology teams consisting of physicists, dosimetrists, nurses and technicians.ConclusionsThe role of the young radiation oncologist in the field of oncology should be proactive in developing new competencies. Above all, it is important to remember that we are dealing with the family members and loved ones of many individuals during the most difficult part of their lives. 相似文献
997.
Hugo Gruson 《Evolution; international journal of organic evolution》2019,73(3):623-625
To what extent do plumage properties and behavior interact to produce visual signals? Simpson and McGraw (2019) propose an elegant and novel experimental set‐up to dissociate behavior and color and assess their relative effects in the resulting iridescent signal. They find that modification of either component leads to a modification of the resulting signal as seen by the receiver, suggesting that sexual selection acts simultaneously on both signal components. 相似文献
998.
999.
Rainer Springhorn 《Pal?ontologische Zeitschrift》1978,52(1-2):19-27
From the Reinbekian deposits of Bocholt (Lower Rhine) a left femur and the distal fragment of a left tibia are described. A comparison with known fossil specimens results no direct conformity. The morphological relationship of the limb bones is nearest to the Monachinae. They are introduced with the termMonotherium sp. Due to their stratigraphical age, in comparison to younger relations, they own some primitive features. 相似文献
1000.
Eneda Pjetri Ria de Haas Simone de Jong Cigdem Gelegen Hugo Oppelaar Linda A. W. Verhagen Marinus J. C. Eijkemans Roger A. Adan Berend Olivier Martien J. Kas 《PloS one》2012,7(11)
Animal studies are very useful in detection of early disease indicators and in unravelling the pathophysiological processes underlying core psychiatric disorder phenotypes. Early indicators are critical for preventive and efficient treatment of progressive psychiatric disorders like anorexia nervosa. Comparable to physical hyperactivity observed in anorexia nervosa patients, in the activity-based anorexia rodent model, mice and rats express paradoxical high voluntary wheel running activity levels when food restricted. Eleven inbred mouse strains and outbred Wistar WU rats were exposed to the activity-based anorexia model in search of identifying susceptibility predictors. Body weight, food intake and wheel running activity levels of each individual mouse and rat were measured. Mouse strains and rats with high wheel running activity levels during food restriction exhibited accelerated body weight loss. Linear mixed models for repeated measures analysis showed that baseline wheel running activity levels preceding the scheduled food restriction phase strongly predicted activity-based anorexia susceptibility (mice: Beta = −0.0158 (±0.003 SE), P<0.0001; rats: Beta = −0.0242 (±0.004 SE), P<0.0001) compared to other baseline parameters. These results suggest that physical activity levels play an important role in activity-based anorexia susceptibility in different rodent species with genetically diverse background. These findings support previous retrospective studies on physical activity levels in anorexia nervosa patients and indicate that pre-morbid physical activity levels could reflect an early indicator for disease severity. 相似文献