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PurposeRegional nodal irradiation (RNI) improved disease-free survival by 3% to 5% in 2 large randomized trials, but this small absolute advantage relies on accurate contouring and dose delivery. We audited our network to determine compliance on regional nodal coverage, contouring, and dosimetric parameters with respect to accepted guidelines.Methods and MaterialsIn our network, we have established a clinical pathway for patients with node-positive breast cancer that guides indications for RNI and dosimetric goals. We reviewed records of 183 patients with nodal macrometastases after upfront surgery or involved nodes of any size after neoadjuvant chemotherapy. Radiation treatment plans were examined to determine lymph node volumes treated, whether nodes were contoured, quality of nodal contours, and whether target coverage and normal organ dosimetric constraints were met when RNI was delivered.ResultsDespite the presence of macrometastases on sentinel lymph node biopsy, no lymph nodes were treated in 2.2% (4 of 183). Of 179 patients who received nodal irradiation, 18 received radiation to axillary levels 1 and 2 only, and 161 patients received RNI. Overall, regional nodes were not treated despite strong indications in 7.6% (14 of 183). Treated nodes were not contoured for 2.2% (4 of 179), and lymph node contours were unacceptable in 15.4% (27 of 175). Of patients receiving RNI, 14.9% (24 of 161) did not have adequate nodal target volume coverage, mean heart dose was >4 Gy for 3.1% (5 of 161), and lung V20 Gy was >35% for 8.7% (14 of 161).ConclusionsAdherence to indications for regional nodal treatment was high, but nodes were either not contoured or had unacceptable contour quality in 18% of plans, and coverage was inadequate in 15%. Because the small disease-free survival advantage seen in trials may be decreased with these deviations, routine clinical practice requires detailed peer review to fully translate results of clinical trials.  相似文献   
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Ticagrelor is a cornerstone of modern antithrombotic therapy alongside aspirin in patients with acute coronary syndrome and after percutaneous coronary intervention. Adverse effects such as bleeding and dyspnea have been associated with premature ticagrelor discontinuation, which may limit any potential advantage of ticagrelor over clopidogrel. The randomized trials of ticagrelor captured adverse events, offering the opportunity to more precisely quantify these effects across studies. Therefore, a meta-analysis of 4 randomized clinical trials of ticagrelor conducted between January 2007 and June 2017 was performed to quantify the incidence and causes of premature ticagrelor discontinuation. Among 66,870 patients followed for a median 18 months, premature ticagrelor discontinuation was seen in 25%; bleeding was the most common cause of discontinuation followed by dyspnea. Versus the comparators, the relative risk of dyspnea-related discontinuation during follow-up was 6.4-fold higher, the relative risk of bleeding was 3.2-fold higher, and the relative risk of discontinuation due to any adverse event was 59% higher for patients receiving ticagrelor. Understanding these potential barriers to adherence to ticagrelor is crucial for informed patient-physician decision making and can inform future efforts to improve ticagrelor adherence. This review discusses the incidence, causes, and biological mechanisms of ticagrelor-related adverse effects and offers strategies to improve adherence to ticagrelor.  相似文献   
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BACKGROUND: Septic shock is an important cause of death in pediatric intensive care units. Initial evaluations have shown that vasopressin may have a role in catecholamine refractory shock in adults. It is important to determine whether children with septic shock have deficiency of vasopressin. This will help in defining the role of vasopressin in septic shock. DESIGN: Prospective cohort study. SETTING: Pediatric intensive care unit of a tertiary care hospital in north India. PATIENTS: Patients were children with septic shock, and controls were children with sepsis but no shock. STUDY DESIGN: Vasopressin levels in plasma were determined by enzyme-linked immunosorbent assay for children with septic shock at diagnosis (baseline) and thereafter at 24, 48, and 96 hrs to determine the time trends. The baseline vasopressin values for children with septic shock were compared with those for children without shock. RESULTS: The median (95% confidence interval) vasopressin level at baseline in children with septic shock was 116 (63.3-130.7) pg/mL, and in children with sepsis but no shock it was 106 (61.7-131.77) pg/mL. The median value for survivors was 76 (44.6-130.9) pg/mL, and for nonsurvivors, 118 (81.7-259) pg/mL (p = .16). The serial values also did not show any significant changes; the values at 24 hrs (n = 17), 48 hrs (n = 16), and 96 hrs (n = 15) were 105 (76.1-125.9), 105 (41.4-155.5), and 109.5 (54.9-154.8) pg/mL, respectively. CONCLUSIONS: The results of our study suggest that vasopressin levels are elevated in children with septic shock and that serial values up to 96 hrs do not show any decline.  相似文献   
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BACKGROUND CONTEXT: Intramedullary fat-containing benign childhood tumors of the cord include lipomas, dermoid cysts, and teratomas. These are embryonal tumors. Most intramedullary fat-containing tumors are solitary. Multiple intramedullary lipomas are rare and may represent a spinal lipomatous malformation. The presence of another intramedullary dermoid tumor in the same case is rare. PURPOSE: The intent of this case report is to look at magnetic resonance features and possible mechanisms of association of these fat-containing intramedullary tumors. STUDY DESIGN/SETTING: A 3-year-old male child presented with spastic quadriplegia. METHODS: Magnetic resonance imaging (MRI) of spine was done on a 1.5-T scanner in different planes. RESULTS: MRI showed multiple intramedullary spinal lipomas with an intramedullary dermoid involving the conus, cord atrophy, and subarachnoid fat droplets. CONCLUSION: Multiple intramedullary lipomas with an intramedullary dermoid represent a form of spinal lipomatous malformation. Both may represent embryogenic mesenchymal inclusions and hamartomatous growth, which can be accurately diagnosed with MRI.  相似文献   
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The ionophore X537A induced swelling of isolated rat mast cells parallel to histamine release. Both actions were depressed by extracellular calcium and BSA, temperatures below 37°C, NEM, PMSF, and TTX, and were enhanced by high potassium and pretreatment of the cells with ATP. DSCG, theophylline, and DFP enhanced the histamine release noted after 10 min of incubation without influencing the swelling action of X537A. The swelling action could not be separated from histamine release and it is suggested that it right be inherent in the mechanism of secretion induced by X537A. The present results further distinguish histamine release induced by the two ionophores X537A and A23187.  相似文献   
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Summary The present communication endeavours to elucidate the mechanism of histamine release from rat peritoneal mast cells induced by selective histamine liberators.Of the different enzymatic processes involved in secretion the following are considered: ecto-ATPase activity in the mast cell, pro-esterase-esterase conversion during histamine secretion, cyclic AMP and microtubule association/dissociation, phospholipase A2 and the effect of phospholipid metabolites on secretion, N-methyl transferase and the methylation of phospholipids and the phosphorylation and desphosphorylation of proteins.  相似文献   
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