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191.
Eduardo Arana-Rueda Alonso Pedrote Lorena Garcia-Riesco Manuel Frutos-Lopez Juan A Sanchez-Brotons 《Indian pacing and electrophysiology journal》2009,9(4):233-237
We report an unusual association of persistent atrial flutter and bundle branch re-entrant ventricular tachycardia in a young patient without structural heart disease. Atrial flutter masked the infra-Hisian conduction disease, was fundamentally dependent on a long PR interval, and could be a possible trigger of ventricular tachycardia. 相似文献
192.
Folate being an important vitamin of B Complex group in our diet plays an important role not only in the synthesis of DNA but also in the maintenance of methylation reactions in the cells. Folate metabolism is influenced by several processes especially its dietary intake and the polymorphisms of the associated genes involved. Aberrant folate metabolism, therefore, affects both methylation as well as the DNA synthesis processes, both of which have been implicated in the development of various diseases. This paper reviews the current knowledge of the processes involved in folate metabolism and consequences of deviant folate metabolism, particular emphasis is given to the polymorphic genes which have been implicated in the development of various diseases in humans, like vascular diseases, Down's syndrome, neural tube defects, psychiatric disorders and cancers. 相似文献
193.
Floral structure and development of representatives of Asteliaceae, Blandfordiaceae, Boryaceae, Doryanthaceae, and Hypoxidaceae,
all members of the `lower' Asparagales, were studied comparatively. The results are discussed in the light of new molecular
systematic studies, but also with regard to established morphological characters in related groups. Stamen shape varies considerably
within and between taxa: the shape of anthers is from X-shaped, sagittate to non-sagittate, they are either latrorse or introrse,
basifixed, centrifixed or dorsifixed. Gynoecia are syncarpous up to the stigmatic region in all taxa. Ovaries of Doryanthaceae
and Hypoxidaceae are inferior, but they are superior in Asteliaceae, Blandfordiaceae and Boryaceae. All ovaries have at least
a short synascidiate zone. With the exception of Astelia alpina (Asteliaceae), the ovaries are trilocular. Ovaries of Asteliaceae contain mucilage, which is secreted from trichomes on the
funicle and on the placenta. Although flowers are polysymmetric at anthesis, they are monosymmetric in earliest stages with
a developmental gradient from adaxial to abaxial. Perianth organs arise individually from either a concave (taxa with inferior
ovary) or convex (taxa with superior ovary) apex. Hypoxidaceae have pollen flowers with free stamens. One species, Curculigo capitulata, has Solanum-type flowers with postgenitally united stamens. It is most probably pollinated by buzzing bees. All other taxa have nectariferous
flowers with internal or external septal nectaries.
Received February 5, 2001 Accepted June 20, 2001 相似文献
194.
S. U. ?str?m M. E. Nordlund F. L. Erickson E. M. Hannig A. S. Bystr?m 《Molecular & general genetics : MGG》1999,261(6):967-976
The Saccharomyces cerevisiae gene RIT1 encodes a phospho-ribosyl transferase that exclusively modifies the initiator tRNA (tRNAMet
i) by the addition of a 2′-O-ribosyl phosphate group to Adenosine 64. As a result, tRNAMet
i is prevented from participating in the elongation steps of protein synthesis. We previously showed that the modification
is not essential for the function of tRNAMet
i in the initiation of translation, since rit1 null strains are viable and show no obvious growth defects. Here, we demonstrate that yeast strains in which a rit1 null allele is combined with mutations in any of the genes for the three subunits of eukaryotic initiation factor-2 (eIF-2),
or with disruption alleles of two of the four initiator methionine tRNA (IMT) genes, show synergistic growth defects. A multicopy plasmid carrying an IMT gene can alleviate these defects. On the other hand, introduction of a high-copy-number plasmid carrying the TEF2 gene, which encodes the eukaryotic elongation factor 1α (eEF-1α), into rit1 null strains with two intact IMT genes had the opposite effect, indicating that increased levels of eEF-1α are deleterious to these strains, presumably due
to sequestration of the unmodified met-tRNAMet
i for elongation. Thus, under conditions in which the components of the ternary met-tRNAMet
i:GTP:eIF-2 complex become limiting or are functionally impaired, the presence of the 2′-O-ribosyl phosphate modification in
tRNAMet
i is important for the provision of adequate amounts of tRNAMet
i for formation of this ternary complex.
Received: 20 November 1998 / Accepted: 7 April 1999 相似文献
195.
Simone Martinelli Oliver H.F. Krumbach Francesca Pantaleoni Simona Coppola Ehsan Amin Luca Pannone Kazem Nouri Luciapia Farina Radovan Dvorsky Francesca Lepri Marcel Buchholzer Raphael Konopatzki Laurence Walsh Katelyn Payne Mary Ella Pierpont Samantha Schrier Vergano Katherine G. Langley Douglas Larsen Ghayda M. Mirzaa 《American journal of human genetics》2018,102(2):309-320
196.
Sen Matsumoto Yasuharu Matsunaga-Lee Nobutaka Masunaga Yuzuru Takano 《Indian pacing and electrophysiology journal》2018,18(4):155-158
A 69-year-old woman with palpitations was referred to our hospital for a second session of atrial fibrillation (AF) catheter ablation. She had a history of AF ablation including pulmonary vein (PV) isolation and persistent left superior vena cava (PLSVC) isolation. Electrophysiologic studies showed the veno-atrial connections that had recovered. After PV isolation was performed, AF was induced by atrial premature contraction (APC) from the PLSVC, and AF storm occurred. During PLSVC isolation, AF was not induced by APC from the PLSVC. PLSVC isolation continued during sinus rhythm. The elimination of the PLSVC potential was difficult to confirm because of the far-field potential of the left ventricle. Then, we performed right ventricular pacing. The remaining PLSVC potential was identified. After that, the PLSVC isolation was successful during right ventricular pacing. Complications were not observed. The patient had no recurrence of AF thereafter. 相似文献
197.
P.E. Peterson J.J. Short R. Tarara C. Valverde E. Rothgarn A.G. Hendrickx 《Journal of medical primatology》1997,26(5):267-275
Abstract: This paper summarizes the spontaneous incidence of congenital defects in the rhesus and cynomolgus macaque colonies (Macaca mulatta and M. fascicularis) at the California Regional Primate Research Center. The computerized database used in this analysis included fetuses, term infants, juveniles, and adults that underwent a necropsy procedure over a 14-year period (1983–1996). The calculated malformation rates were 0.9% (40/4,390) and 0.3% (3/965) for the rhesus and cynomolgus monkey, respectively. Most of the observed malformations in both species affected the musculoskeletal and the cardiovascular systems, while a smaller number of defects were observed in the gastrointestinal, urogenital, endocrine, and central nervous systems. Inbreeding did not contribute to the spontaneous malformation incidence and there was no predilection for sex (male vs. female) or housing (indoors vs. outdoors) among the malformed cases. This spontaneous malformation database in our macaque colony aids in the interpretation of defects that occur in an experimental study as well as in the ongoing assessment of a healthy nonhuman primate breeding colony. 相似文献
198.
Spinal lipoma as a dysembryogenetic anomaly: Four unusual cases of ectopic iliac rib within the spinal lipoma 下载免费PDF全文
199.
Residential agricultural pesticide exposures and risks of selected birth defects among offspring in the San Joaquin Valley of California 下载免费PDF全文
200.
W. M. C. Koenraadt N. Grewal O. Y. Gaidoukevitch M. C. DeRuiter A. C. Gittenberger-de Groot M. M. Bartelings E. R. Holman R. J. M. Klautz M. J. Schalij M. R. M. Jongbloed 《Netherlands heart journal》2016,24(2):127-133