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81.
Navaneethan U Gutierrez NG Jegadeesan R Venkatesh PGK Sanaka MR Vargo JJ Parsi MA 《World journal of gastrointestinal endoscopy》2014,6(3):74-81
AIM: To identify potential factors that can predict adverse short-term outcomes in patients with acute cholangitis undergoing endoscopic retrograde cholangiopancreatography (ERCP).METHODS: Retrospective analysis of consecutive patients admitted to our center for acute cholangitis and underwent ERCP from 2001 to 2012. Involvement of two or more organ systems was termed as organ failure (OF). Cardiovascular failure was defined based on a systolic blood pressure of < 90 mmHg despite fluid replacement and/or requiring vasopressor treatment; respiratory failure if the Pa02/Fi02 ratio was < 300 mmHg and/or required mechanical ventilation; coagulopathy if the platelet count was < 80; and renal insufficiency if serum creatinine was > 1.9 mg/dL. Variables associated with short term adverse clinical outcomes defined as persistent OF and/or 30-d mortality was determined.RESULTS: A total of 172 patients (median age 62 years, 56.4% female) were included. The median door to ERCP time was 17 h. Bile duct stones were the most common etiology (n = 67, 39.2%). In multivariate analysis, factors that were independently associated with persistent OF and/or 30-d mortality included American Society of Anesthesiology (ASA) physical classification score > 3 (OR = 7.70; 95%CI: 2.73-24.40), presence of systemic inflammatory response syndrome (OR = 3.67; 95%CI: 1.34-10.3) and door to ERCP time greater than 72 h (OR = 3.36; 95%CI: 1.12-10.20). Door to ERCP time greater than 72 h was also associated with 70% increase in the mean length of stay (P < 0.001). Every one point increase in the ASA physical classification and every 1 mg/dL increase in the pre-ERCP bilirubin level was associated with a 34% and 2% increase in the mean length of hospital stay, respectively. Transfer status did not impact clinical outcomes.CONCLUSION: Higher ASA physical classification and delays in ERCP are associated with adverse clinical outcomes and prolonged length of hospital stay in patients with acute cholangitis undergoing ERCP. 相似文献
82.
Navaneethan U Konjeti R Venkatesh PGK Sanaka MR Parsi MA 《World journal of gastrointestinal endoscopy》2014,6(5):200-208
AIM: To study the cannulation and complication rates of early pre-cut sphincterotomy vs persistent attempts at cannulation by standard approach.METHODS: Systematic search of PubMed, EMBASE, Web of Science, and the Cochrane Library for relevant studies published up to February 2013. The main outcome measurements were cannulation rates and postendoscopic retrograde cholangiopancreatography(ERCP) complications. A comprehensive systematic search of the Cochrane library, PubMed, Google scholar, Scopus, National Institutes of Health, meta-register of controlled trials and published proceedings from major Gastroenterology journals and meetings until February 2013 was conducted using keywords. All Prospective randomized controlled trials(RCT) studies whichmet our inclusion criteria were included in the analysis. Prospective non-randomized studies and retrospective studies were excluded from our meta-analysis. The main outcomes of interest were post-ERCP pancreatitis, overall complication rates including cholangitis, ERCPrelated bleeding, perforation and cannulation success rates. RESULTS: Seven RCTs with a total of 1039 patients were included in the meta-analysis based on selection criteria. The overall cannulation rate was 90% in the pre-cut sphincterotomy vs 86.3% in the persistent attempts group(OR = 1.98; 95%CI: 0.70-5.65). The risk of post-ERCP pancreatitis(PEP) was not different between the two groups(3.9% in the pre-cut sphincterotomy vs 6.1% in the persistent attempts group, OR = 0.58, 95%CI: 0.32-1.05). Similarly, there was no statistically significant difference between the groups for overall complication rate including PEP, cholangitis, bleeding, and perforation(6.2% vs 6.9%, OR = 0.85, 95%CI: 0.51-1.41). CONCLUSION: This meta-analysis suggests that precut sphincterotomy and persistent attempts at cannulation are comparable in terms of overall complication rates. Early pre-cut implementation does not increase PEP complications. 相似文献
83.
Walker MD Wahren CH Hollister RD Henry GH Ahlquist LE Alatalo JM Bret-Harte MS Calef MP Callaghan TV Carroll AB Epstein HE Jónsdóttir IS Klein JA Magnússon B Molau U Oberbauer SF Rewa SP Robinson CH Shaver GR Suding KN Thompson CC Tolvanen A Totland Ø Turner PL Tweedie CE Webber PJ Wookey PA 《Proceedings of the National Academy of Sciences of the United States of America》2006,103(5):1342-1346
Recent observations of changes in some tundra ecosystems appear to be responses to a warming climate. Several experimental studies have shown that tundra plants and ecosystems can respond strongly to environmental change, including warming; however, most studies were limited to a single location and were of short duration and based on a variety of experimental designs. In addition, comparisons among studies are difficult because a variety of techniques have been used to achieve experimental warming and different measurements have been used to assess responses. We used metaanalysis on plant community measurements from standardized warming experiments at 11 locations across the tundra biome involved in the International Tundra Experiment. The passive warming treatment increased plant-level air temperature by 1-3 degrees C, which is in the range of predicted and observed warming for tundra regions. Responses were rapid and detected in whole plant communities after only two growing seasons. Overall, warming increased height and cover of deciduous shrubs and graminoids, decreased cover of mosses and lichens, and decreased species diversity and evenness. These results predict that warming will cause a decline in biodiversity across a wide variety of tundra, at least in the short term. They also provide rigorous experimental evidence that recently observed increases in shrub cover in many tundra regions are in response to climate warming. These changes have important implications for processes and interactions within tundra ecosystems and between tundra and the atmosphere. 相似文献
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Degree of cervical carotid artery stenosis and hemispheric stroke: duplex US findings 总被引:2,自引:0,他引:2
Duplex ultrasound (US) scans of 110 carotid arteries ipsilateral to hemispheric strokes were compared with scans of 90 asymptomatic vessels in the same patients to determine the relative prevalence of stenotic lesions. In addition, scans of paired carotid arteries in patients with stroke involving only one cerebral hemisphere were compared to determine whether the incriminated side demonstrated a greater degree of stenosis than the asymptomatic side. The duplex US findings demonstrated a positive correlation between stenosis and hemispheric stroke. However, only 20% of carotid arteries ipsilateral to hemispheric stroke showed a reduction in diameter greater than 70%, compared with 5% of asymptomatic vessels. A minimal difference was demonstrated between the symptomatic and asymptomatic groups with respect to lesser degrees of stenosis. In paired carotid arteries, the degree of stenosis of the symptomatic vessel exceeded that of the asymptomatic vessel in only 43% of cases. These results suggest that the prevalence of severe carotid stenosis in stroke patients has been previously overestimated. The findings also emphasize the need for further investigation of other plaque-related risk factors that may enhance stroke prevention through improved selection of surgical or medical therapy. Factors currently under investigation include plaque ulceration, intraplaque hemorrhage, plaque echogenicity, and the effects of sequential stenoses. 相似文献
89.
H DSouza RC Joshi T Ganesh V Subramani G Vasu R Kumar PK Julka GK Rath 《Journal of Medical Imaging and Radiation Oncology》1999,43(3):342-345
Stereotactic irradiation, either in the form of stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) of brain lesions requires high precision and submillimetre accuracy in the isocentre, the main determinants being gantry and couch rotations. It is thus necessary to evaluate the isocentre variation due to gantry and couch rotations in the particular setup for SRS/SRT. This paper describes variation in the isocentre of a Philips (now Elekta) SL-20 linear accelerator modified for adapting a couch-mounted radiosurgery system. By considering the isocentre as defined by a mechanical index as the standard, the variations in the isocentre of the linear accelerator were independently measured for the gantry and for couch rotations. The variation in the isocentre for gantry rotation was found to be between 0.1 mm and 0.9 mm, conforming to the submillimetre accuracy required for SRS/SRT. However, the isocentre variation due to couch rotation varied considerably, possibly because the couch is of the RAM type. The isocentre variation due to couch rotation is rectified by microadjusting the couch mount at the time of treatment using a laser target localizing frame. It is our conclusion that a modified linear accelerator can be used for performing SRS/SRT after careful and separate evaluation of the isocentre stability due to gantry and couch rotations. 相似文献
90.
Stainless steel vascular occlusion coils provide a convenient and effective means for occluding large vessels. Occasionally, coagulopathies or extremely high-flow states delay or preclude the formation of an effective thrombus around this device. A technique is described for pretreating these coils with a thrombin solution. This pretreatment assures a prompt and effective occlusion of the target vessel. 相似文献