980 resultados para MGS3 stratigraphic segment
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In this paper, the NPMLE in the one-dimensional line segment problem is defined and studied, where line segments on the real line through two non-overlapping intervals are observed. The self-consistency equations for the NPMLE are defined and a quick algorithm for solving them is provided. Supnorm weak convergence to a Gaussian process and efficiency of the NPMLE is proved. The problem has a strong geological application in the study of the lifespan of species.
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PURPOSE: To assess the outcomes in patients who required 1 or more vitreoretinal interventions for posterior segment complications arising from elective uneventful cataract surgery. SETTING: Tertiary referral center, single-center study. METHODS: A retrospective interventional case series included 56 consecutive patients who were referred for surgical correction of posterior segment complications within 6 months of cataract surgery. The study period was between 1996 and 2003, and the minimum follow-up was 5 months. RESULTS: Posterior segment complications were resolved with a single surgical intervention in 40 cases (71.4%). Within 5 months of primary surgical correction, persisting or newly arising posterior segment complications were noted in 16 cases (28.6%). After a mean of 2.1 +/- 1.4 (SD) additional surgeries, the number of eyes with posterior segment problems decreased to 7 (12.5%) (P = .035). Posterior segment complications requiring more than 1 vitreoretinal intervention included retinal detachment, endophthalmitis, and choroidal hemorrhages. After primary correction surgery, the mean best corrected visual acuity increased from 0.15 +/- 0.24 to 0.37 +/- 0.33 (P = .001) after a single intervention and to 0.39 +/- 0.32 (P>.05) after additional interventions. Although the intraocular pressure (IOP) decreased from 21.8 +/- 16.6 mm Hg to 14.9 +/- 3.4 mm Hg (P = .008), 4 (7.1%) consecutive vascular optic atrophies occurred. A reduction in corneal transparency was observed in 46.4% of patients before primary surgical correction and 12.5% after primary surgical correction (P<.001). CONCLUSIONS: In many cases, posterior segment complications arising from cataract surgery could be repaired with favorable functional and anatomical outcomes by a single vitreoretinal intervention. Additional surgery, if requested, provided stabilization of the anatomical and functional outcomes.
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BACKGROUND: The off-label use of topical tacrolimus (Protopic) for inflammatory external eye diseases is gaining popularity. However, there are no reports on the safety profile of this new treatment option. PATIENTS AND METHODS: We treated six patients with different inflammatory eye diseases with topical tacrolimus (Protopic 0.03 %) as off-label use in addition to the conventional anti-inflammatory treatment. Patients were interviewed for side effects and serum drug concentrations were measured under steady state conditions one hour after topical application of tacrolimus ointment. RESULTS: Two patients reported a slight burning sensation immediately after application, in one patient we found a slight worsening of the dry eye problems. No patient abandoned the treatment due to side effects. Serum drug concentrations remained below the analytical threshold in all cases (< 1.5 ng/ml). CONCLUSIONS: Tacrolimus for the topical treatment of anterior segment inflammatory eye diseases is well tolerated without detectable systemic drug resorption.
Stratigraphic Studies of the Ordovician and Devonian Formations Throughout the Northwest Plains Area
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As yet the knowledge of Ordovician and Devonian physiography in this vast northwest region remains almost a complete secret. Very little, in any, work has been done along this line with the exception of those areas where the various formations outcrop.
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The definition of spinal instability is still controversial. For this reason, it is essential to better understand the difference in biomechanical behaviour between healthy and degenerated human spinal segments in vivo. A novel computer-assisted instrument was developed with the objective to characterize the biomechanical parameters of the spinal segment. Investigation of the viscoelastic properties as well as the dynamic spinal stiffness was performed during a minimally invasive procedure (microdiscectomy) on five patients. Measurements were performed intraoperatively and the protocol consisted of a dynamic part, where spinal stiffness was computed, and a static part, where force relaxation of the segment under constant elongation was studied. The repeatability of the measurement procedure was demonstrated with five replicated tests. The spinal segment tissues were found to have viscoelastic properties. Preliminary tests confirmed a decrease in stiffness after decompression surgery. Patients with non-relaxed muscles showed higher stiffness and relaxation rate compared to patients with relaxed muscles, which can be explained by the contraction and relaxation reflex of muscles under fast and then static elongation. The results show the usefulness of the biomechanical characterization of the human lumbar spinal segment to improve the understanding of the contribution of individual anatomical structures to spinal stability.
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We introduce an algorithm (called REDFITmc2) for spectrum estimation in the presence of timescale errors. It is based on the Lomb-Scargle periodogram for unevenly spaced time series, in combination with the Welch's Overlapped Segment Averaging procedure, bootstrap bias correction and persistence estimation. The timescale errors are modelled parametrically and included in the simulations for determining (1) the upper levels of the spectrum of the red-noise AR(1) alternative and (2) the uncertainty of the frequency of a spectral peak. Application of REDFITmc2 to ice core and stalagmite records of palaeoclimate allowed a more realistic evaluation of spectral peaks than when ignoring this source of uncertainty. The results support qualitatively the intuition that stronger effects on the spectrum estimate (decreased detectability and increased frequency uncertainty) occur for higher frequencies. The surplus information brought by algorithm REDFITmc2 is that those effects are quantified. Regarding timescale construction, not only the fixpoints, dating errors and the functional form of the age-depth model play a role. Also the joint distribution of all time points (serial correlation, stratigraphic order) determines spectrum estimation.
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OBJECTIVES This study sought to study the efficacy and safety of newer-generation drug-eluting stents (DES) compared with bare-metal stents (BMS) in an appropriately powered population of patients with ST-segment elevation myocardial infarction (STEMI). BACKGROUND Among patients with STEMI, early generation DES improved efficacy but not safety compared with BMS. Newer-generation DES, everolimus-eluting stents, and biolimus A9-eluting stents, have been shown to improve clinical outcomes compared with early generation DES. METHODS Individual patient data for 2,665 STEMI patients enrolled in 2 large-scale randomized clinical trials comparing newer-generation DES with BMS were pooled: 1,326 patients received a newer-generation DES (everolimus-eluting stent or biolimus A9-eluting stent), whereas the remaining 1,329 patients received a BMS. Random-effects models were used to assess differences between the 2 groups for the device-oriented composite endpoint of cardiac death, target-vessel reinfarction, and target-lesion revascularization and the patient-oriented composite endpoint of all-cause death, any infarction, and any revascularization at 1 year. RESULTS Newer-generation DES substantially reduce the risk of the device-oriented composite endpoint compared with BMS at 1 year (relative risk [RR]: 0.58; 95% confidence interval [CI]: 0.43 to 0.79; p = 0.0004). Similarly, the risk of the patient-oriented composite endpoint was lower with newer-generation DES than BMS (RR: 0.78; 95% CI: 0.63 to 0.96; p = 0.02). Differences in favor of newer-generation DES were driven by both a lower risk of repeat revascularization of the target lesion (RR: 0.33; 95% CI: 0.20 to 0.52; p < 0.0001) and a lower risk of target-vessel infarction (RR: 0.36; 95% CI: 0.14 to 0.92; p = 0.03). Newer-generation DES also reduced the risk of definite stent thrombosis (RR: 0.35; 95% CI: 0.16 to 0.75; p = 0.006) compared with BMS. CONCLUSIONS Among patients with STEMI, newer-generation DES improve safety and efficacy compared with BMS throughout 1 year. It remains to be determined whether the differences in favor of newer-generation DES are sustained during long-term follow-up.
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BACKGROUND Data on temporal trends in outcomes, gender differences, and adherence to evidence-based therapy (EBT) of diabetic patients with ST-segment elevation myocardial infarction (STEMI) are sparse. METHODS We performed a retrospective analysis of prospectively acquired data on 3565 diabetic (2412 males and 1153 females) STEMI patients enrolled in the Swiss AMIS Plus registry between 1997 and 2010 and compared in-hospital outcomes and adherence to EBT with the nondiabetic population (n=15,531). RESULTS In-hospital mortality dramatically decreased in diabetic patients, from 19.9% in 1997 to 9.0% in 2010 (p trend<0.001) with an age-adjusted decrease of 6% per year of admission. Similar trends were observed for age-adjusted reinfarction (OR 0.86, p<0.001), cardiogenic shock (OR 0.88, p<0.001), as well as death, reinfarction, or stroke (OR 0.92, p<0.001). However, the mortality benefit over time was observed in diabetic males (p trend=0.006) but not females (p trend=0.082). In addition, mortality remained twice as high in diabetic patients compared with nondiabetic ones (12.1 vs. 6.1%, p<0.001) and diabetes was identified as independent predictor of mortality (OR 1.23, p=0.022). Within the diabetic cohort, females had higher mortality than males (16.1 vs. 10.2%, p<0.001) and female gender independently predicted in-hospital mortality (OR 1.45, p=0.015). Adherence to EBT significantly improved over time in diabetic patients (p trend<0.001) but remained inferior - especially in women - to the one of nondiabetic individuals. CONCLUSIONS In-hospital mortality and morbidity of diabetic STEMI patients in Switzerland improved dramatically over time but, compared with nondiabetic counterparts, gaps in outcomes as well as EBT use persisted, especially in women.
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Over the past five decades, management of acute ST-segment elevation myocardial infarction (STEMI) has evolved substantially. Current treatment encompasses a systematic chain of network activation, antithrombotic drugs, and rapid instigation of mechanical reperfusion, although pharmacoinvasive strategies remain relevant. Secondary prevention with drugs and lifestyle modifications completes the contemporary management package. Despite a tangible improvement in outcomes, STEMI remains a frequent cause of morbidity and mortality, justifying the quest to find new therapeutic avenues. Ways to reduce delays in doing coronary angioplasty after STEMI onset include early recognition of symptoms by patients and prehospital diagnosis by paramedics so that the emergency room can be bypassed in favour of direct admission to the catheterisation laboratory. Mechanical reperfusion can be optimised by improvements to stent design, whereas visualisation of infarct size has been improved by developments in cardiac MRI. Novel treatments to modulate the inflammatory component of atherosclerosis and the vulnerable plaque include use of bioresorbable vascular scaffolds and anti-proliferative drugs. Translational efforts to improve patients' outcomes after STEMI in relation to cardioprotection, cardiac remodelling, and regeneration are also being realised. This is the third in a Series of three papers about ST-segment elevation myocardial infarction.
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Several patients with chronic critical limb ischemia show angiographically an isolated popliteal segment (IPS) and a single calf vessel (SCV) with no direct communication to the former. In this situation a bypass can be inserted from the common femoral artery to the IPS or to the SCV. The results of 73 bypass procedures--40 to an isolated popliteal segment and 33 to a single calf vessel for limb salvage--were prospectively evaluated. Eighty percent of the grafts were performed with an autogenous saphenous vein (ASV), the rest with a thin wall polytetrafluoroethylene (PTFE) prosthesis. The mean age of our patients was 75 years and many suffered from cardiovascular disease. The operative mortality rate was 3% and the mean postoperative survival 32 months. Three year patency and limb salvage rates for ASV grafts was 83% and 87% (IPS) respectively 77% and 76% (MCV); for PTFE grafts 58% and 88% (IPS) respectively 17% and 50% (MCV). There was no significant difference found in patency and limb salvage rates of the two procedures if the graft was an autogenous saphenous vein (p > 0.05). The PTFE prosthesis was only suitable for grafts inserted to the isolated popliteal segment.
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OBJECTIVE To evaluate the etiology and treatment of bilateral hydronephrosis not responding to bladder substitute drainage after ileal bladder substitution using an afferent isoperistaltic tubular segment. MATERIALS AND METHODS A retrospective analysis was performed of a consecutive series of 739 patients who had undergone bladder substitution from April 1985 to August 2012. RESULTS Of the 739 ileal bladder substitute patients, 10 (1.4%) developed bilateral hydronephrosis unresponsive to complete bladder substitute drainage. The etiology was stenosis of the afferent isoperistaltic tubular segment. The median interval to presentation was 131 months (range 45-192). The incidence of afferent tubular segment stenosis was significantly higher in the 61 ileal bladder substitute patients with recurrent urinary tract infection (9 [15%]) than in the 678 without recurrent urinary tract infection (1 [0.15%]; P <.001). Urine cultures revealed mixed infections (34%), Escherichia coli (18%), Staphylococcus aureus (13%), enterococci (11%), Candida (8%), Klebsiella (8%), and others (8%). Seven patients underwent 10 endourologic interventions, only 1 of which was successful (10%). After failed endourologic treatment, 7 open surgical revisions with resection of the stricture were performed, with all 7 (100%) successful. CONCLUSION Bilateral dilation of the upper urinary tract after ileal orthotopic bladder substitution unresponsive to complete bladder substitute drainage is likely to be caused by stenosis of the afferent isoperistaltic tubular segment. The stenosis occurs almost exclusively in patients with long-lasting, recurrent urinary tract infection and can develop many years after the ileal bladder substitution. Minimally invasive endourologic treatment is usually unsuccessful; however, open surgical revision offers excellent results.