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511.
Selvaraj R Arunprasath P Karthikeyan B George G Balachander J 《Indian pacing and electrophysiology journal》2010,10(9):426-428
We describe a patient with an implanted pacemaker for impaired AV conduction who presented with an incessant tachycardia. EP study showed that the tachycardia was atrioventricular nodal reentrant tachycardia (AVNRT) with repeated spontaneous initiation because of poor or absent antegrade fast pathway conduction. Slow pathway ablation was successful in terminating the tachycardia and making it non-inducible. 相似文献
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Aruliah Rajasekar Balakrishnan Anandkumar Sundaram Maruthamuthu Yen-Peng Ting Pattanathu K. S. M. Rahman 《Applied microbiology and biotechnology》2010,85(4):1175-1188
Microbiologically influenced corrosion is a problem commonly encountered in facilities in the oil and gas industries. The
present study describes bacterial enumeration and identification in diesel and naphtha pipelines located in the northwest
and southwest region in India, using traditional cultivation technique and 16S rDNA gene sequencing. Phylogenetic analysis
of 16S rRNA sequences of the isolates was carried out, and the samples obtained from the diesel and naphtha-transporting pipelines
showed the occurrence of 11 bacterial species namely Serratia marcescens ACE2, Bacillus subtilis AR12, Bacillus cereus ACE4, Pseudomonas aeruginosa AI1, Klebsiella oxytoca ACP, Pseudomonas stutzeri AP2, Bacillus litoralis AN1, Bacillus sp., Bacillus pumilus AR2, Bacillus carboniphilus AR3, and Bacillus megaterium AR4. Sulfate-reducing bacteria were not detected in samples from both pipelines. The dominant bacterial species identified
in the petroleum pipeline samples were B. cereus and S. marcescens in the diesel and naphtha pipelines, respectively. Therefore, several types of bacteria may be involved in biocorrosion arising
from natural biofilms that develop in industrial facilities. In addition, localized (pitting) corrosion of the pipeline steel
in the presence of the consortia was observed by scanning electron microscopy analysis. The potential role of each species
in biofilm formation and steel corrosion is discussed. 相似文献
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The effect of troxerutin on γ-radiation-induced DNA strand breaks in different tissues of mice in vivo and formations of the micronuclei were studied in human peripheral blood lymphocytes ex vivo and mice blood reticulocytes in vivo. Treatments with 1 mM troxerutin significantly inhibited the micronuclei induction in the human lymphocytes. Troxerutin protected
the human peripheral blood leucocytes from radiation-induced DNA strand breaks in a concentration dependent manner under ex vivo condition of irradiation (2 Gy). Intraperitoneal administration of troxerutin (175 mg/kg body weight) to mice before and
after whole body radiation exposure inhibited micronuclei formation in blood reticulocytes significantly. The administration
of different doses (75, 125 and 175 mg/kg body weight) of troxerutin 1 h prior to 4 Gy γ-radiation exposure showed dose-dependent
decrease in the yield of DNA strand breaks in murine blood leucocytes and bone marrow cells. The dose-dependent protection
was more pronounced in bone marrow cells than in blood leucocytes. Administration of 175 mg/kg body weight of the drug (i.p.)
1 h prior or immediately after whole body irradiation of mice showed that the decrease in strand breaks depended on the post-irradiation
interval at which the analysis was done. The observed time-dependent decrease in the DNA strand breaks could be attributed
to enhanced DNA repair in troxerutin administered animals. Thus in addition to anti-erythrocytic, anti-thrombic, fibrinolytic
and oedema-protective rheological activity, troxerutin offers protection against γ-radiation-induced micronuclei formation
and DNA strand breaks and enhances repair of radiation-induced DNA strand breaks. (Mol Cell Biochem xxx: 57–68, 2005) 相似文献
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This paper examines the patterns of timing of births of women using data from the Canadian Fertility Survey of 1984. Semi-Markovian schemes are applied to the maternity histories of the 5315 sample women in their reproductive ages in order to measure the intensity and timing of childbearing. Age-and-duration-specific transition probabilities are found to have substantially changed for the more recent birth cohorts compared to the older cohorts. 相似文献
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