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91.
For patients undergoing elective percutaneous coronary intervention (PCI), procedural anticoagulation with bivalirudin was previously shown to significantly reduce bleeding complications at the cost of a modest increase in ischemic events compared with unfractionated heparin (UFH) and glycoprotein IIb/IIIa inhibitors (GPIs). However, the excess bleeding in patients treated with UFH and GPIs may have been caused by excessively high UFH doses and increased activated clotting times. This study sought to determine the bleeding risk of targeted low-dose UFH with GPIs compared with bivalirudin in patients undergoing elective PCI. Of 1,205 patients undergoing elective PCI, 602 underwent PCI with adjunctive UFH and GPIs with the UFH dose targeted to an activated clotting time of approximately 250 seconds, and 603 patients matched for baseline characteristics underwent PCI with bivalirudin. Outcomes were analyzed for major bleeding (hematocrit decrease >15%, gastrointestinal bleed, or major hematoma) and 6-month major adverse cardiac events (death, myocardial infarction, and target-lesion revascularization). The maximum activated clotting time achieved was 261.7 +/- 61.6 seconds in the UFH/GPI group and 355.4 +/- 66.6 in the bivalirudin group (p <0.001). In-hospital major bleeding rates were similar between groups (1.8% UFH/GPI vs 1.7% bivalirudin; p = 0.83), as were transfusion requirements (1.2% UFH/GPI vs 0.5% bivalirudin; p = 0.61). The 6-month major adverse cardiac event rate was also similar between groups (9.5% UFH/GPI vs 9.0% bivalirudin; p = 0.81). In conclusion, there were no significant differences in major bleeding and 6-month major adverse cardiac events for patients undergoing elective PCI treated with targeted low-dose UFH and GPIs compared with those treated with bivalirudin.  相似文献   
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Digestive Diseases and Sciences - While the pathogenesis of inflammatory bowel disease (IBD) is incompletely understood, disruption of epithelial integrity is suspected to play a prominent role in...  相似文献   
95.
The purpose of this work was to assess the reproducibility of diffusion imaging, and in particular the apparent diffusion coefficient (ADC), intra‐voxel incoherent motion (IVIM) parameters and diffusion tensor imaging (DTI) parameters, across multiple centres using clinically available protocols with limited harmonization between sequences. An ice–water phantom and nine healthy volunteers were scanned across fives centres on eight scanners (four Siemens 1.5T, four Philips 3T). The mean ADC, IVIM parameters (diffusion coefficient D and perfusion fraction f) and DTI parameters (mean diffusivity MD and fractional anisotropy FA), were measured in grey matter, white matter and specific brain sub‐regions. A mixed effect model was used to measure the intra‐ and inter‐scanner coefficient of variation (CV) for each of the five parameters. ADC, D, MD and FA had a good intra‐ and inter‐scanner reproducibility in both grey and white matter, with a CV ranging between 1% and 7.4%; mean 2.6%. Other brain regions also showed high levels of reproducibility except for small structures such as the choroid plexus. The IVIM parameter f had a higher intra‐scanner CV of 8.4% and inter‐scanner CV of 24.8%. No major difference in the inter‐scanner CV for ADC, D, MD and FA was observed when analysing the 1.5T and 3T scanners separately. ADC, D, MD and FA all showed good intra‐scanner reproducibility, with the inter‐scanner reproducibility being comparable or faring slightly worse, suggesting that using data from multiple scanners does not have an adverse effect compared with using data from the same scanner. The IVIM parameter f had a poorer inter‐scanner CV when scanners of different field strengths were combined, and the parameter was also affected by the scan acquisition resolution. This study shows that the majority of diffusion MRI derived parameters are robust across 1.5T and 3T scanners and suitable for use in multi‐centre clinical studies and trials. © 2015 The Authors NMR in Biomedicine Published by John Wiley & Sons Ltd.  相似文献   
96.

Purpose

Besides the lipid-lowering properties, statins are thought to have anti-inflammatory effects and it has been shown that statins directly attenuate the inflammatory stress response after surgical trauma. The aim of the study was to examine the association between preoperative statin use and 30-day mortality as well as postoperative complications after curative-intended surgery for colorectal cancer.

Methods

The study was a Danish nationwide register-based observational study. A total of 29,352 patients undergoing surgery for colorectal cancer between January 1, 2003, and December 31, 2012, were included in the study. At the time of surgery, 5961 were registered as statin users. The outcomes were 30-day mortality and risk of postoperative complications.

Results

The adjusted hazard ratio of 30-day mortality was 0.91 (95 CI 0.80–1.04, P?=?0.16) among statin users compared with the non-statin group. There was no difference between the two groups regarding the risk of infectious complications (sepsis, anastomotic leakage, pneumonia) (odds ratio 0.95, 95% CI 0.86–1.05, P?=?0.31). For other postoperative complications (cardiovascular events, stroke, renal failure, respiratory insufficiency, and thromboembolic events), there was no significant difference between the two groups (odds ratio 0.89, 95% CI 0.78–1.01, P?=?0.06).

Conclusion

The study did not show an improved 30-day survival after surgery for colorectal cancer in patients treated with statins in the year preceding surgery. No overall association with the risk of postoperative complications was shown.
  相似文献   
97.

Objective

We compared the analgesic efficacy and incidence of side effects when low‐dose (0.3 mg/kg) ketamine (LDK) is administered as a slow infusion (SI) over 15 minutes versus an intravenous push (IVP) over 1 minute.

Methods

This was a prospective, randomized, double‐blind, double‐dummy, placebo‐controlled trial of adult ED patients presenting with moderate to severe pain (numerical rating scale [NRS] score ≥ 5). Patients received 0.3 mg/kg ketamine administered either as a SI or a IVP. Our primary outcome was the proportion of patients experiencing any psychoperceptual side effect over 60 minutes. A secondary outcome was incidence of moderate or greater psychoperceptual side effects. Additional outcomes included reduction in pain NRS scores at 60 minutes and percent maximum summed pain intensity difference (%SPID).

Results

Fifty‐nine participants completed the study. A total of 86.2% of the IVP arm and 70.0% of the SI arm experienced any side effect (difference = 16.2%, 95% confidence interval [CI] = –5.4 to 37.8). We found a large reduction in moderate or greater psychoperceptual side effects with SI administration—75.9% reported moderate or greater side effects versus 43.4% in the SI arm (difference = 32.5%, 95% CI = 7.9 to 57.1). Additionally, the IVP arm experienced more hallucinations (n = 8, 27.6%) than the SI arm (SI n = 2, 6.7%, difference = 20.9%, 95% CI = 1.8 to 43.4). We found no significant differences in analgesic efficacy. At 60 minutes, the mean %SPID values in the IVP and SI arms were 39.9 and 33.5%, respectively, with a difference of 6.5% (95% CI = –5.8 to 18.7).

Conclusion

Most patients who are administered LDK experience a psychoperceptual side effect regardless of administration via SI or IVP. However, patients receiving LDK as a SI reported significantly fewer moderate or greater psychoperceptual side effects and hallucinations with equivalent analgesia.
  相似文献   
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Purpose

The study purposes were to mathematically link scores of the Brief Pain Inventory Pain Interference Subscale and the Short Form-36 Bodily Pain Subscale (legacy pain interference measures) to the NIH Patient-Reported Outcome Measurement Information System (PROMIS®) Pain Interference (PROMIS-PI) metric and evaluate results.

Methods

Linking was accomplished using both equipercentile and item response theory (IRT) methods. Item parameters for legacy items were estimated on the PROMIS-PI metric to allow for pattern scoring. Crosswalk tables also were developed that associated raw scores (summed or average) on legacy measures to PROMIS-PI scores. For each linking strategy, participants’ actual PROMIS-PI scores were compared to those predicted based on their legacy scores. To assess the impact of different sample sizes, we conducted random resampling with replacement across 10,000 replications with sample sizes of n = 25, 50, and 75.

Results

Analyses supported the assumption that all three scales were measuring similar constructs. IRT methods produced marginally better results than equipercentile linking. Accuracy of the links was substantially affected by sample size.

Conclusions

The linking tools (crosswalks and item parameter estimates) developed in this study are robust methods for estimating the PROMIS-PI scores of samples based on legacy measures. We recommend using pattern scoring for users who have the necessary software and score crosswalks for those who do not.
  相似文献   
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