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101.
102.

Objectives:

To evaluate the usefulness of the Forrest classification and the complete Rockall score with customary cut-off values for assessing the risk of adverse events in patients with upper gastrointestinal bleeding (UGI-B) subject to after-hours emergency oesophago-gastro-duodenoscopy (E-EGD) within six hours after admission.

Methods:

The medical records of patients with non-variceal UGI-B proven by after-hours endoscopy were analysed. For ''high risk'' situations (Forrest stage Ia–IIb/complete Rockall score > 2), univariate analysis was conducted to evaluate odds ratio for reaching the study endpoints (30-day and one-year mortality, re-bleeding, hospital stay ≥ 3 days).

Results:

During the study period (75 months), 86 cases (85 patients) met the inclusion criteria. Patients ''age was 66.36 ± 14.38 years; 60.5% were male. Mean duration of hospital stay was 15.21 ± 19.24 days. Mortality rate was 16.7% (30 days) and 32.9% (one year); 14% of patients re-bled. Univariate analysis of post-endoscopic Rockall score ≥ 2 showed an odds ratio of 6.09 for death within 30 days (p = 0.04). No other significant correlations were found.

Conclusion:

In patients with UGI-B subject to after-hours endoscopy, a ''high-risk'' Rockall score permits an estimation of the risk of death within 30 days but not of re-bleeding. A ''high-risk '' Forrest score is not significantly associated with the study endpoints.  相似文献   
103.
104.
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner.  相似文献   
105.
Post-transplant lymphoproliferative disease remains a complication with a high morbidity and mortality. The present study examined 291 pediatric liver transplants performed in 263 children from October 1984 to December 1999. Post-transplant lymphoproliferative disease has an overall incidence of 12%. Tacrolimus and cyclosporine had a similar incidence of post-transplant lymphoproliferative disease. Fifty-six per cent of patients who developed post-transplant lymphoproliferative disease were Epstein-Barr virus negative at the time of transplantation. Mean time of conversion to Epstein-Barr virus positivity was 1.1 years after liver transplantation. Ten per cent of those who developed post-transplant lymphoproliferative disease never had Epstein-Barr virus detected. Mean time from Epstein-Barr virus positivity to detection of post-transplant lymphoproliferative disease was 2.68 years, and 3.13 years from liver transplantation (OLTx) to post-transplant lymphoproliferative disease. There was a 35% incidence of mortality. Deaths occurred a mean of 0.76 years after diagnosis of post-transplant lymphoproliferative disease. Most cases of post-transplant lymphoproliferative disease had extranodal location. There was one recurrence in 10% of patients, and two in 3%. All recurrent cases were seen in recipients who became Epstein-Barr virus positive after transplantation. There has been a decrease in the incidence of post-transplant lymphoproliferative disease from 15% to 9% to 4%. Post-transplant lymphoproliferative disease should be diagnosed promptly and treated aggressively. The best treatment, however, seems to be prevention, starting in the immediate postoperative period. Survivors should be monitored for both recurrence of post-transplant lymphoproliferative disease and acute cellular rejection.  相似文献   
106.
There has been a significant increase in the number of reported cases of Acanthamoeba keratitis reported internationally over the last 24 months. Diagnosing Acanthamoeba keratitis is often difficult and part of the difficulty is attributed to the variability of presentation. This article provides a comprehensive photographic reference of common and uncommon clinical signs of Acanthamoeba keratitis.  相似文献   
107.
Inhaled nitric oxide (iNO) is used to treat preterm infants with hypoxaemic respiratory failure. In this study we describe the long-term survival and neurodevelopmental status of high-risk preterm infants enrolled into a randomized controlled trial of iNO therapy. Information regarding long-term outcome was available for all 25 children enrolled in the original trial who survived until discharge from hospital. Formal, blinded, developmental assessment and neurological examinations were performed in 21 out of 22 children still alive at 30 mo of age, corrected for prematurity. No significant differences were found in long-term mortality (12/20 vs 8/22, RR 1.65, 95% CI 0.87-3.3), neurodevelopmental delay (4/7 vs 9/14, RR 0.89, 95% CI 0.37-1.75), severe neurodisability (0/7 vs 5/14, p = 0.12) or cerebral palsy (0/7 vs 2/14, p = 0.53) between iNO-treated and control infants. CONCLUSION: In this study there was no evidence of a significant effect on either survival or long-term neurodevelopmental status in infants treated with iNO.  相似文献   
108.
109.
The feasibility of using magnetic resonance (MR) imaging to estimate myocardial infarct size was explored in an in vitro model using only the inherent differences in contrast between infarcted and noninfarcted myocardium. Eight dogs underwent coronary occlusion; their hearts were removed 6 hours later. Estimates of T2 for normal and infarcted myocardium were derived from MR images. Infarct size was quantified anatomically using triphenyltetrazolium-chloride (TTC) staining and compared with MR estimates. The T2 values derived from the images clearly discriminated between infarcted (126 +/- 22 msec) and normal myocardium (88 +/- 10 msec, P less than .05), providing images with good contrast between normal and infarcted myocardium. Comparable differences in T2 values were also noted from spectrometric determinations. Estimates of infarct size by MR imaging compared well with TTC estimates (r = 0.98) over a wide range of infarct sizes from 3% to 29% of the left ventricular mass. These results suggest the potential for in vivo quantification of infarct size based on the inherent contrast difference between infarcted and normal myocardium.  相似文献   
110.
Charnley prostheses, retrieved at revision surgery, were studied to assess the effects of friction on the total hip replacement procedure. Frictional resistance was measured using the Durham hip function simulator under both dry and lubricated conditions. The friction factor values (f) for the explanted prostheses were found to have a non- Gaussian distribution with medians of 0.13 [inter-quartile range (IQR) 0.10-0.16] and 0.06 (IQR 0.005-0.08) for dry and lubricated (n = 0.01 Pa s) regimes, respectively. New Charnley prostheses had values of f equal to 0.11 +/- 0.025 and 0.04 +/- 0.01 under the same conditions, and showed no large deviation from a Gaussian distribution. There was found to be a statistically significant difference in the medians of the friction factors for new and retrieved prostheses in the lubricated regime. Ingression of cement into the worn region of the cup was found to increase the friction factor significantly under dry conditions. There was no evidence of an increase in the friction factor or torque for those joints that had a loose socket with respect to those that were fixed at revision. A decrease in the frictional torque against number of cycles undergone by the joint in vivo may indicate that a fatigue-type process may have a role in the loosening of the socket. However, this relationship was found not to be significant for friction measured under lubricated conditions and it seems unlikely that the frictional torque generated in this type of prosthesis will contribute significantly to the long-term loosening of the socket.   相似文献   
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