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The accuracies of an analog-indicating electronic device, the Dentometer, and of an audio-indicating device, the Sono-Explorer, were compared to each other and to the radiographic method of tooth length determination. Readings obtained by the Dentometer were shorter, an average of 0.28 +/- 0.64 mm than those obtained by the Sono-Explorer (p less than 0.001) and 0.32 +/- 0.63 mm shorter than the results obtained by the calculated working length (p less than 0.001). No statistically significant difference was found between the readings of the Sono-Explorer and the calculated radiographic working length. The results indicate that the measurements calculated by the radiographic method were longer than those obtained by the electronic method of tooth length determination. The statistically significant difference found between the two devices indicates that to determine the accuracy of electronic devices, they should be tested and compared to other methods or devices. 相似文献
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Peptic ulcer and bleeding events associated with rofecoxib in a 3-year colorectal adenoma chemoprevention trial 总被引:5,自引:0,他引:5
Lanas A Baron JA Sandler RS Horgan K Bolognese J Oxenius B Quan H Watson D Cook TJ Schoen R Burke C Loftus S Niv Y Ridell R Morton D Bresalier R 《Gastroenterology》2007,132(2):490-497
BACKGROUND & AIMS: Our aim was to establish the incidence of symptomatic upper gastrointestinal ulcers, ulcer perforation, ulcer obstruction, or bleeding episodes (PUBs) associated with the use of selective cyclooxygenase-2 inhibitors at standard clinical doses compared with placebo. We report here on the PUB outcomes associated with the use of rofecoxib 25 mg in a 3-year, multicenter, double-blind, placebo-controlled trial designed to determine the effect of rofecoxib on the risk of recurrent neoplastic polyps of the colon. METHODS: A total of 2587 patients with a history of colorectal adenomas underwent randomization to 25 mg/day of rofecoxib or to placebo. Investigator-reported PUBs were adjudicated by an external blinded committee. Kaplan-Meier and Cox proportional hazards techniques were used to estimate incidence and relative risks of PUBs in an intention-to-treat analysis. RESULTS: Patients assigned to rofecoxib had a higher incidence of confirmed PUBs than those randomized to placebo (.88 vs .18 events per 100 patient-years; relative risk, 4.9; 95% confidence interval, 1.98-14.54). The incidence of confirmed complicated PUBs (ulcer perforation, obstruction, or bleeds) was low, but was numerically higher in the rofecoxib than in the placebo group (.23 vs .06 events per 100 patient-years; relative risk, 3.8; 95% confidence interval, .72-37.46; P = .14). Rofecoxib increased the incidence of confirmed PUBs vs placebo in both low-dose aspirin users and nonusers. CONCLUSIONS: Among patients with a history of colorectal adenomas, the long-term use of 25 mg/day of rofecoxib was associated with an increased risk of clinically relevant upper gastrointestinal events when compared with placebo. 相似文献
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Flexible sigmoidoscopy is a valid screening tool for the early detection of colorectal cancer (CRC). Recently published long-term
data from UKFSST, a randomized controlled trial, demonstrate a 33% reduction in colorectal cancer incidence and a 43% decrease
in colorectal cancer mortality, with once-in-a-lifetime screening. On the other hand, data from the NORCCAP trial with a similar
protocol show no reduction in CRC incidence and only nonsignificant decrease in CRC mortality at 7 years. At best, flexible
sigmoidoscopy can detect only 70% of cancers and polyps as it does not detect the 40% of proximal neoplasms which are not
associated with a distal lesion. The advantage of flexible sigmoidoscopy over other screening modalities lies in its safety
profile, patient tolerance, and overall acceptance. Its technical simplicity, short duration, and cost-effectiveness advance
its applicability to mass screening programs. 相似文献
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Doron Boltin Alex Vilkin Zohar Levi Ori Elkayam Yaron Niv 《Digestive diseases and sciences》2010,55(7):1975-1981
Background
JC virus (JCV), a polyoma virus, is the etiological agent of progressive multifocal leukoencephalopathy in immunosuppressed patients. JCV T-Ag has proven oncogenic potential and is expressed in colonic polyps and carcinomas. We proposed that the prevalence of JCV T-Ag DNA is higher in the normal gastrointestinal (GI) mucosa of immunosuppressed patients compared with their immunocompetent counterparts. 相似文献28.
A Golan O Stolik S Wexler D Niv A Ber M P David 《International journal of fertility》1991,36(5):317-320
In an attempt to investigate the relative paucity of intraperitoneal adhesions after cesarean sections, we tested the effect of amniotic fluid on adhesion formation in rat model. Trauma was induced to the uterine serosa in 40 rats. Amniotic fluid was intraperitoneally instilled in 20 rats and saline in another 20 rats acting as controls. No inhibitory effect of the amniotic fluid could be demonstrated. The effect of the amniotic fluid and the saline solutions on fibroblastic proliferation was examined in vitro using fibroblastic cell cultures. No direct effect on fibroblast proliferation was found. It is concluded that it is not the direct effect of the spilled amniotic fluid that inhibits adhesion formation after the performance of cesarean sections. 相似文献
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J Niv J B Lessing J Hartuv M R Peyser 《American journal of obstetrics and gynecology》1992,166(3):930-931
A 27-year-old woman was admitted to the hospital because of profuse vaginal bleeding from a vaginal laceration caused by the impact of water to the perineum after sliding down a water chute. At the time of the accident the patient was using a vaginal tampon. The potential mechanism for this trauma is discussed. 相似文献