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61.
Melloni C Alexander KP Milford-Beland S Newby LK Szczech LA Pollack CV Kirk JD Christenson RH Harrington RA Gibler WB Ohman EM Peterson ED Roe MT;Crusade Investigators 《Clinical cardiology》2008,31(3):125-129
BACKGROUND: The prognostic value of cardiac troponins (cTn) in patients with non-ST-segment elevation acute coronary syndromes (NSTE ACS) and chronic kidney disease (CKD) is debated. HYPOTHESIS: We tested the performance of cTnI and cTnT for risk stratification in patients with CKD and evaluated the prognostic significance of cTnI and cTnT elevations by their magnitude across the range of CKD severity. METHODS: We examined correlations among cTn elevation, CKD, and in-hospital mortality in 31,586 high-risk patients with NSTE ACS included in the Can Rapid Risk Stratification of Unstable Angina Patients Suppress ADverse Outcomes with Early Implementation of the American College of Cardiology/American Heart Association Guidelines initiative (CRUSADE). Cardiac tropinins I and T levels were categorized as ratios of each site's upper limit of normal (ULN) for myocardial necrosis: normal (cTn ratio < or =1 x ULN), mild (cTn ratio > 1-3 x ULN), and major (cTn ratio > 3 x ULN) elevation. Estimated glomerular filtration rate (eGFR) was calculated using the abbreviated Modification of Diet in Renal Disease equation. Stages of CKD were categorized as normal to mild (eGFR > 60 mL/min), moderate (eGFR 30-60 mL/min), or severe (eGFR < 30 mL/min). RESULTS: Mortality increased more steeply across CKD stages (2.0%-12.9%) than across cTn ratio categories (2.7%-5.4%). In normal or mild CKD, mortality was low regardless of cTn elevations. In moderate CKD, mortality increased incrementally with cTnI (3.3% versus 5.4% versus 7.4%) and cTnT (3.7% versus 5.3% versus 7.3%) elevation. Among severe CKD patients, only major cTn elevations further distinguished risk (cTnI: 10.1% versus 9.7% versus 14.6%; cTnT: 7.0% versus 5.7% versus 14.0%). CONCLUSIONS: In patients with CKD, cTnI and cTnT perform equally in differentiating short-term prognosis following NSTE ACS; however, the prognostic impact of cTn is dependent upon the degree of CKD severity. 相似文献
62.
Cardiac muscle models. An overextension of series elasticity? 总被引:1,自引:0,他引:1
63.
E. J. Wawszkiewicz H. A. Schneider B. Starcher J. Pollack J. B. Neilands 《Proceedings of the National Academy of Sciences of the United States of America》1971,68(11):2870-2873
Salmonellosis pacifarin activity is detected by an increased survivorship of mice, doubly infected with avirulent and virulent Salmonella typhimurium, when heretofore unknown agents, found in certain natural foodstuffs and in the supernatants of certain bacterial cultures, are fed to the infected animals as dietary supplements. We now announce the identity of one of these agents: it is enterobactin, a cyclic trimer of 2,3-dihydroxy-N-benzoyl-L-serine. Basal diets enriched with as little as 2 mg of crystalline trimer per kg of diet show pacifarin activity to a statistically significant degree. Diets supplemented with as much as 100 mg of the monomer per kg of diet show no such activity. 相似文献
64.
S Charlap B Kimmel J Berezow S Molinas J Strom J Wexler H Willens N Klein S Pollack W H Frishman 《Angiology》1985,36(4):240-252
The short-term (1 month) and long-term (6 months) safety of combination lidoflazine-propranolol therapy was investigated in an open trial of 15 patients with stable angina of effort. The possible advantages of adding lidoflazine (titrated to 360 mg daily) to patients having a therapeutic response to propranolol (80-400 mg daily) was also evaluated. Effects on non-invasive indexes of left ventricular function (echocardiography, systolic time intervals, radionuclide ventriculography) and exercise tolerance (treadmill exercise testing) were determined. There was no change in mean resting heart rate with the combination therapy, although one patient developed sinus bradycardia at a rate of 44 and had to have his propranolol dose reduced. Electrocardiographic analysis showed significant prolongation of the QTc intervals on lidoflazine-propranolol therapy compared to propranolol alone, with 3 patients having QTc interval prolongation to above .53 seconds, but there was no evidence of increased arrhythmogenesis with the combination therapy compared to propranolol alone. Left ventricular end-diastolic volume index tended to rise with combination therapy. However, lidoflazine-propranolol therapy did not produce any significant effects on resting ejection fraction determined by M-mode echocardiography or by radionuclide ventriculography. Radionuclide ventriculography determined peak exercise ejection fractions were also not significantly changed with combination therapy compared to propranolol alone. There were only small, insignificant improvements in exercise tolerance with the lidoflazine-propranolol combination treatment compared to propranolol alone. It is concluded that lidoflazine-propranolol combination therapy is generally safe but has the potential of causing serious adverse effects in certain patients, i.e. those with sick sinus disease, prolonged QTc intervals, and severe baseline left ventricular dysfunction, and that caution must be exercised in its use. Furthermore, it would appear that combination therapy provides only slight, if any, improvements in exercise tolerance in patients with chronic stable angina having a therapeutic response to oral propranolol. 相似文献
65.
Outcome and prognostic factors for children with supratentorial primitive neuroectodermal tumors treated with carboplatin during radiotherapy: A report from the Children's Oncology Group 下载免费PDF全文
Regina I. Jakacki MD Peter C. Burger MD Mehmet Kocak PhD James M. Boyett PhD Joel Goldwein MD Minesh Mehta MB eChB Roger J. Packer MD Nancy J. Tarbell MD Ian F. Pollack MD 《Pediatric blood & cancer》2015,62(5):776-783
Background
Supratentorial PNETs (sPNET) are uncommon embryonal malignancies of the central nervous system whose prognosis has historically been poor. We evaluated the outcome and prognostic factors of children with sPNET treated prospectively on a Children's Oncology Group trial.Procedure
Following surgery, patients received craniospinal radiotherapy with concurrent carboplatin followed by six months of maintenance chemotherapy with cyclophosphamide and vincristine.Results
Five‐year overall survival (OS) and progression‐free survival (PFS) for all patients was 58 ± 7% and 48 ± 7%. For patients with pineoblastoma (n = 23), five‐year OS and PFS was 81 ± 9% and 62 ± 11%. Extent of resection but not M‐stage was prognostic. Five‐year OS and PFS for 37 patients with non‐pineal tumors (NPsPNET) was 44 ± 8% and 39 ± 8%, significantly worse than for PB (P = 0.055 and 0.009 respectively). Extent of resection and major radiotherapy deviations were prognostic. Five year OS was 59 +/? 11.4% for those undergoing complete resection versus 10.4 +/? 7% for those who did not (P = 0.017). Central pathologic review called 14 (38%) “classic” sPNET, 8 (22%) “undifferentiated” and 13 (35%) “malignant gliomas.” There was no significant difference between the subgroups, although survival distributions approached significance when the combined “classic” and “undifferentiated” group was compared to the “malignant gliomas.”Conclusions
Carboplatin during RT followed by 6 months of non‐intensive chemotherapy is a feasible treatment strategy for patients with sPNET. Aggressive surgical resection should be attempted if feasible. The classification of supratentorial small cell malignancies can be difficult. Pediatr Blood Cancer 2015;62:776–783. © 2015 Wiley Periodicals, Inc.66.
67.
Megan L. Clayton Katherine Clegg Smith Roni A. Neff Keshia M. Pollack Margaret Ensminger 《International journal of occupational and environmental health》2015,21(4):314-327
Background
Foodborne disease is a significant problem worldwide. Research exploring sources of outbreaks indicates a pronounced role for food workers'' improper health and hygiene practice.Objective
To investigate food workers'' perceptions of factors that impact proper food safety practice.Method
Interviews with food service workers in Baltimore, MD, USA discussing food safety practices and factors that impact implementation in the workplace. A social ecological model organizes multiple levels of influence on health and hygiene behavior.Results
Issues raised by interviewees include factors across the five levels of the social ecological model, and confirm findings from previous work. Interviews also reveal many factors not highlighted in prior work, including issues with food service policies and procedures, working conditions (e.g., pay and benefits), community resources, and state and federal policies.Conclusion
Food safety interventions should adopt an ecological orientation that accounts for factors at multiple levels, including workers'' social and structural context, that impact food safety practice. 相似文献68.
NMR‐based approach to the analysis of radiopharmaceuticals: radiochemical purity,specific activity,and radioactive concentration values by proton and tritium NMR spectroscopy 下载免费PDF全文
David J. Schenk Peter G. Dormer David Hesk Scott R. Pollack Carolee Flader Lavey 《Journal of labelled compounds & radiopharmaceuticals》2015,58(7):291-298
Compounds containing tritium are widely used across the drug discovery and development landscape. These materials are widely utilized because they can be efficiently synthesized and produced at high specific activity. Results from internally calibrated 3H and 1H nuclear magnetic resonance (NMR) spectroscopy suggests that at least in some cases, this calibrated approach could supplement or potentially replace radio‐high‐performance liquid chromatography for radiochemical purity, dilution and scintillation counting for the measurement of radioactivity per volume, and liquid chromatography/mass spectrometry analysis for the determination of specific activity. In summary, the NMR‐derived values agreed with those from the standard approaches to within 1% to 9% for solution count and specific activity. Additionally, the NMR‐derived values for radiochemical purity deviated by less than 5%. A benefit of this method is that these values may be calculated at the same time that 3H NMR analysis provides the location and distribution of tritium atoms within the molecule. Presented and discussed here is the application of this method, advantages and disadvantages of the approach, and a rationale for utilizing internally calibrated 1H and 3H NMR spectroscopy for specific activity, radioactive concentration, and radiochemical purity whenever acquiring 3H NMR for tritium location. 相似文献
69.
Hematopoietic stem cell donor registry strategies for assigning search determinants and matching relationships 总被引:4,自引:0,他引:4
Hurley CK Setterholm M Lau M Pollack MS Noreen H Howard A Fernandez-Vina M Kukuruga D Müller CR Venance M Wade JA Oudshoorn M Raffoux C Enczmann J Wernet P Maiers M 《Bone marrow transplantation》2004,33(4):443-450
Registries and cord blood banks around the world collect and store the HLA types of volunteers in order to identify matched unrelated donors for patients requiring hematopoietic stem cell transplantation. This task is complicated by the many formats in which HLA types are provided by the testing laboratories (types obtained by serology vs by DNA-based methods; high vs intermediate vs low resolution) and by the need to identify which of these diverse types are most likely to match the HLA assignments of a searching patient as closely as possible. Conversion of the assignments to 'search determinants' may be included within the algorithm used to select and prioritize a list of potentially suitable donors, either as an aid to matching or as a tool to optimize the performance of comparisons within large data files. The strategies used by registries to create search determinants are described. A set of search determinants, utilized by the National Marrow Donor Program, is provided as an example and is intended to initiate further discussion aimed at understanding the process used by each registry with the possibility of developing a standard process among registries worldwide. 相似文献
70.
Antibody against tuberlin: the specific visualization of cytoplasmic microtubules in tissue culture cells. 总被引:24,自引:11,他引:24 下载免费PDF全文
K Weber R Pollack T Bibring 《Proceedings of the National Academy of Sciences of the United States of America》1975,72(2):459-463
Cytoplasmic microtubules in tissue culture cells can be directly visualized by immunofluorescence microscopy. Antibody against tubulin from the outer doublets of sea urchin sperm flagella decorates a network of fine cytoplasmic fibers in a variety of cell lines of human, monkey, rat, mouse, and chicken origin. These fibers are separate and of uniform thickness and are seen throughout the cytoplasm. The fibers disappear either in a medium containing colchicine or after subjection of the cells to low temperature. The same treatments do not destroy the microfilamentous structures that are visualized by means of antibody against actin. When tryspin-treated enucleated cells are replated and then stained with antibody against tubulin, the fibers can be seen to traverse the entire enucleated cytoplasm. 相似文献