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排序方式: 共有1098条查询结果,搜索用时 15 毫秒
1.
Diane C. Ling Bryanna L. Moppins Colin E. Champ Vikram C. Gorantla Sushil Beriwal 《Practical radiation oncology》2021,11(1):e30-e35
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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Sameer Arora Kamal Shemisa Muthiah Vaduganathan Arman Qamar Ankur Gupta Sushil K. Garg Dharam J. Kumbhani Helen Mayo Houman Khalili Ambarish Pandey Sandeep R. Das 《Journal of the American College of Cardiology》2019,73(19):2454-2464
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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Rakesh Lodha Subbiah Vivekanandhan Manjunatha Sarthi Sushil K Kabra 《Pediatric critical care medicine》2006,7(3):220-224
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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Temperature-mediated heteroduplex analysis for detection of pncA mutations associated with pyrazinamide resistance and differentiation between Mycobacterium tuberculosis and Mycobacterium bovis by denaturing high- performance liquid chromatography
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Mohamed AM Bastola DR Morlock GP Cooksey RC Hinrichs SH 《Journal of clinical microbiology》2004,42(3):1016-1023
The goal of this study was to apply temperature-mediated heteroduplex analysis using denaturing high-performance liquid chromatography to identify pyrazinamide (PZA) resistance in Mycobacterium tuberculosis isolates and simultaneously differentiate between M. tuberculosis and Mycobacterium bovis. Features that contributed to an optimal assay included the use of two different reference probes for the pncA gene targets from wild-type M. tuberculosis and wild-type M. bovis, optimization of the column temperature, increasing the starting concentration of the elution buffer, and reducing the rate of elution buffer increase (slope). A total of 69 strains were studied, including 48 wild-type M. tuberculosis strains (13 were PZA-resistant strains) and 21 M. bovis strains (8 were BCG strains). In all isolates tested, wild-type M. tuberculosis generated a single-peak pattern when mixed with the M. tuberculosis probe and a double-peak pattern with the M. bovis probe. In contrast, all M. bovis isolates generated a double-peak pattern when mixed with the M. tuberculosis probe and a single-peak pattern with the M. bovis probe. PZA-resistant mutant M. tuberculosis isolates generated characteristic patterns that were easily distinguishable from both wild-type M. tuberculosis and M. bovis isolates. Chromatographic patterns generated by the two reference probes allowed the rapid detection of PZA resistance with the simultaneous ability to distinguish between M. tuberculosis and M. bovis. This approach may allow the detection of drug resistance-associated mutations, with potential application to clinical and epidemiological aspects of tuberculosis control. 相似文献
8.
The amygdala (AMY) plays an important role in initiating appropriate neurobehavioral responses to emotionally arousing events. Its major efferents from the central nucleus (Ace) to the basal forebrain, hypothalamus and brainstem permit it to influence sleep mechanisms. To characterize further the neuronal activity of AMY during sleep and wakefulness, we recorded single neuronal activity in Ace across behavioral states in freely moving, normally behaving rats. Of the 49 neurons recorded from Ace, 24 neurons had firing patterns related to sleep-wakefulness (S-W). Of these, 50% (n = 12) had a high firing frequency during wakefulness (W) or both W and REM sleep (REM), 12% (n = 3) were non-REM (NREM)-related, 17% (n = 4) had a high firing rate in REM (REM-ON), and 20% (n = 5) fired at a low rate during REM. Because serotonin introduced into AMY during REM induces short-latency changes of state, we also studied the effects of low frequency (1 Hz) electrical stimulation of the dorsal raphe nucleus (DRN) on Ace neurons. All REM-ON neurons recorded from Ace were inhibited by DRN stimulation, and other cell types were unaffected. Thus, we found that the majority of cells in Ace related to S-W fired slowly during NREM and increased their discharge during W and/or REM, and that the DRN has the potential for modulating the spontaneous activity of REM-ON cells in rats. 相似文献
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Beum PV Bastola DR Cheng PW 《American journal of respiratory cell and molecular biology》2003,29(1):48-56
Enzymes which exhibit core 2 beta1,6 N-acetylglucosaminyltransferase (C2GnT) activity play important roles in physiologic processes including the inflammatory response and immune system function, and C2GnT activity is regulated during processes, such as T cell activation and cellular differentiation. In this study, we have examined the regulation of C2GnT activity in the H292 airway epithelial cell line by epidermal growth factor (EGF), which has been previously shown to upregulate expression of the airway mucin MUC5AC in this cell line. We found that EGF suppressed C2GnT activity in a time- and dose-dependent fashion, and also suppressed core 4 beta1,6 N-acetylglucosaminyltransferase (C4GnT) activity. Consistent with the suppression of C4GnT activity, Northern blotting results showed that EGF preferentially inhibited the M isoform of C2GnT, which forms core 2, core 4, and blood group I beta1,6 branched carbohydrate structures, while the L isoform, which forms only the core 2 structure, was only modestly affected. Furthermore, EGF treatment resulted in a shift in the carbohydrate structure of FLAG-tagged MUC1 expressed in the cells from core 2-based toward core 1-based structures, consistent with the inhibitory effects of EGF on C2GnT. Transforming growth factor alpha mimicked the effect of EGF on C2GnT, implicating the EGF receptor (EGF-R) in C2GnT suppression, and the EGF-R tyrosine kinase inhibitor AG1478 blocked C2GnT suppression, confirming the role of EGF-R in the inhibition of C2GnT expression. Also, PD98059, a specific inhibitor of mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK)1/2 in the Ras-mitogen-activated protein kinase pathway, completely blocked the EGF suppressive effect, suggesting possible involvement of the Ras-mitogen-activated protein kinase pathway in EGF-mediated downregulation of C2GnT. The results of this study suggest that exposure of airway cells to EGF may result in remodeling of mucin carbohydrate structure, potentially altering the biological properties of the cells. 相似文献