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51.
Braffman BH; Coleman BG; Ramchandani P; Arger PH; Nodine CF; Dinsmore BJ; Louie A; Betsch SE 《Radiology》1994,190(3):797
52.
Kirkpatrick SE; Pitlick PT; Naliboff J; Friedman WF 《The American journal of physiology》1976,231(2):495-500
53.
54.
V. Phan T. Blydt-Hansen J. Feber N. Alos S. Arora S. Atkinson L. Bell C. Clarson R. Couch E. A. Cummings G. Filler R. M. Grant J. Grimmer D. Hebert B. Lentle J. Ma M. Matzinger J. Midgley M. Pinsk C. Rodd N. Shenouda R. Stein D. Stephure S. Taback K. Williams F. Rauch K. Siminoski L. M. Ward 《Osteoporosis international》2014,25(2):627-637
Summary
Incident vertebral fractures and lumbar spine bone mineral density (BMD) were assessed in the 12 months following glucocorticoid initiation in 65 children with nephrotic syndrome. The incidence of vertebral fractures was low at 12 months (6 %) and most patients demonstrated recovery in BMD Z-scores by this time point.Introduction
Vertebral fracture (VF) incidence following glucocorticoid (GC) initiation has not been previously reported in pediatric nephrotic syndrome.Methods
VF was assessed on radiographs (Genant method); lumbar spine bone mineral density (LS BMD) was evaluated by dual-energy X-ray absorptiometry.Results
Sixty-five children were followed to 12 months post-GC initiation (median age, 5.4 years; range, 2.3–17.9). Three of 54 children with radiographs (6 %; 95 % confidence interval (CI), 2–15 %) had incident VF at 1 year. The mean LS BMD Z-score was below the healthy average at baseline (mean ± standard deviation (SD), ?0.5?±?1.1; p?=?0.001) and at 3 months (?0.6?±?1.1; p?<?0.001), but not at 6 months (?0.3?±?1.3; p?=?0.066) or 12 months (?0.3?±?1.2; p?=?0.066). Mixed effect modeling showed a significant increase in LS BMD Z-scores between 3 and 12 months (0.22 SD; 95 % CI, 0.08 to 0.36; p?=?0.003). A subgroup (N?=?16; 25 %) had LS BMD Z-scores that were ≤?1.0 at 12 months. In these children, each additional 1,000 mg/m2 of GC received in the first 3 months was associated with a decrease in LS BMD Z-score by 0.39 at 12 months (95 % CI, ?0.71 to ?0.07; p?=?0.017).Conclusions
The incidence of VF at 1 year was low and LS BMD Z-scores improved by 12 months in the majority. Twenty-five percent of children had LS BMD Z-scores ≤?1.0 at 12 months. In these children, LS BMD Z-scores were inversely associated with early GC exposure, despite similar GC exposure compared to the rest of the cohort. 相似文献55.
56.
The effects of antioxidant supplementation during Percoll preparation on human sperm DNA integrity 总被引:20,自引:6,他引:20
Hughes CM; Lewis SE; McKelvey-Martin VJ; Thompson W 《Human reproduction (Oxford, England)》1998,13(5):1240-1247
The integrity of sperm DNA is crucial for the maintenance of genetic
health. A major source of damage is reactive oxygen species (ROS)
generation; therefore, antioxidants may afford protection to sperm DNA. The
objectives of the study were, first, to measure the effects of antioxidant
supplementation in vitro on endogenous DNA damage in spermatozoa using the
single cell gel electrophoresis (comet) assay and, second, to assess the
effect of antioxidant supplementation given prior to X-ray irradiation on
induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll
centrifugation in the presence of ascorbic acid (300, 600 microM), alpha
tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5,
10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand
breakage was measured using the comet assay. Sperm DNA was protected from
DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60
microM) and urate (400 microM). These antioxidants provided protection from
subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or
ascorbate and alpha tocopherol together induced further DNA damage.
Supplementation in vitro with the antioxidants ascorbate, urate and alpha
tocopherol separately has beneficial effects for sperm DNA integrity.
相似文献
57.
标 题 应用ATⅡ受体拮抗剂抗高血压治疗作 者 KjeldsenSE,OmvikP. 参考文献 TidsskrNorLaegeforen,1996,116:504~507研究疾病 高血压病。目 的 评估氯沙坦对心血管死亡率及非致死性心肌梗死和非脑卒中发生率的影响,同时评估该药对充血性心力衰竭或心绞痛所致的总死亡率和住院率的影响,以及长期应用氯沙坦对发生新诊断糖尿病的影响。设 计 随机、三盲、对照研究。病人资料 8300例年龄55~80岁、收缩压在160~200mmHg、舒张压在95~115mmHg的高血压患者,ECG上有左室… 相似文献
58.
Ketai LH; Williamson MR; Telepak RJ; Levy H; Koster FT; Nolte KB; Allen SE 《Radiology》1994,191(3):665
59.
Peter R. Buseck Rafal E. Dunin-Borkowski Bertrand Devouard Richard B. Frankel Martha R. McCartney Paul A. Midgley Mihly Psfai Matthew Weyland 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(24):13490-13495
Nanocrystals of magnetite (Fe(3)O(4)) in a meteorite from Mars provide the strongest, albeit controversial, evidence for the former presence of extraterrestrial life. The morphological and size resemblance of the crystals from meteorite ALH84001 to crystals formed by certain terrestrial bacteria has been used in support of the biological origin of the extraterrestrial minerals. By using tomographic and holographic methods in a transmission electron microscope, we show that the three-dimensional shapes of such nanocrystals can be defined, that the detailed morphologies of individual crystals from three bacterial strains differ, and that none uniquely match those reported from the Martian meteorite. In contrast to previous accounts, we argue that the existing crystallographic and morphological evidence is inadequate to support the inference of former life on Mars. 相似文献
60.
A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern. 相似文献