oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 164 )

2018 ( 164 )

2017 ( 150 )

2016 ( 188 )

Custom range...

Search Results: 1 - 10 of 90093 matches for " Allan I Bloom "
All listed articles are free for downloading (OA Articles)
Page 1 /90093
Display every page Item
Trans-arterial chemo-embolization is safe and effective for very elderly patients with hepatocellular carcinoma
Matan J Cohen,Allan I Bloom,Orly Barak,Alexander Klimov
World Journal of Gastroenterology , 2013, DOI: 10.3748/wjg.v19.i16.2521
Abstract: AIM: To assess the safety and efficacy of trans-arterial chemo-embolization (TACE) in very elderly patients. METHODS: A prospective cohort study, from 2001 to 2010, compared clinical outcomes following TACE between patients > 75 years old and younger patients (aged between 65 and 75 years and younger than 65 years) with hepatocellular carcinoma (HCC), diagnosed according to the European Association for the Study of the Liver and the American Association for the Study of Liver Diseases criteria. The decision that patients were not candidates for curative therapy was made by a multidisciplinary HCC team. Data collected included demographics, co-morbidities, liver disease etiology, liver disease severity and the number of procedures. The primary outcome was mortality; secondary outcomes included post-embolization syndrome (nausea, fever, abdominal right upper quadrant pain, increase in liver enzymes with no evidence of sepsis and with a clinical course limited to 3-4 d post procedure) and 30-d complications. Additionally, changes in liver enzyme measurements were assessed [alanine and aspartate aminotransferase (ALT and AST), gamma-glutamyl transpeptidase and alkaline phosphatase] in the week following TACE. Analysis employed both univariate and multivariate methods (Cox regression models). RESULTS: Of 102 patients who underwent TACE as sole treatment, 10 patients (9.8%) were > 80 years old at diagnosis; 13 (12.7%) were between 75 and 80 years, 45 (44.1%) were between 65 and 75 years and 34 (33.3%) were younger than 65 years. Survival analysis demonstrated similar survival patterns between the elderly patients and younger patients. Age was also not associated with the adverse event rate. Survival rates at 1, 2 and 3 years from diagnosis were 74%, 37% and 31% among patients < 65 years; 83%, 66% and 48% among patients aged 65 to 75 years; and 86%, 41% and 23% among patients > 75 years. There were no differences between the age groups in the pre-procedural care, including preventive treatment for contrast nephropathy and prophylactic antibiotics. Multivariate survival analysis, controlling for disease stage at diagnosis with the Barcelona Clinic Liver Cancer score, number of TACE procedures, sex and alpha-fetoprotein level at the time of diagnosis, found no significant difference in the mortality hazard for elderly vs younger patients, and there were no differences in post-procedural complications. Serum creatinine levels did not change after 55% of the procedures, in all age groups. In 42% of all procedures, serum creatinine levels increased by no more than
Complications of high grade liver injuries: management and outcomewith focus on bile leaks
Miklosh Bala, Samir Gazalla, Mohammad Faroja, Allan I Bloom, Gideon Zamir, Avraham I Rivkind, Gidon Almogy
Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine , 2012, DOI: 10.1186/1757-7241-20-20
Abstract: This is a retrospective study of patients with liver injury admitted to Hadassah-Hebrew University Medical Centre over a 10-year period. Grade 3-5 injuries were considered to be high grade. Collected data included the number and types of liver-related complications. Interventions which were required for these complications in patients who survived longer than 24 hours were analysed.Of 398 patients with liver trauma, 64 (16%) were found to have high-grade liver injuries. Mechanism of injury was blunt trauma in 43 cases, and penetrating in 21. Forty patients (62%) required operative treatment. Among survivors 22 patients (47.8%) developed liver-related complications which required additional interventional treatment. Bilomas and bile leaks were diagnosed in 16 cases post-injury. The diagnosis of bile leaks was suspected with abdominal CT scan, which revealed intraabdominal collections (n = 6), and ascites (n = 2). Three patients had continuous biliary leak from intraabdominal drains left after laparotomy. Nine patients required ERCP with biliary stent placement, and 2 required percutaneous transhepatic biliary drainage. ERCP failed in one case. Four angioembolizations (AE) were performed in 3 patients for rebleeding. Surgical treatment was found to be associated with higher complication rate. AE at admission was associated with a significantly higher rate of biliary complications. There were 24 deaths (37%), the majority from uncontrolled haemorrhage (18 patients). There were only 2 hepatic-related mortalities due to liver failure.A high complication rate following high-grade liver injuries should be anticipated. In patients with clinical evidence of biliary complications, CT scan is a useful diagnostic and therapeutic tool. AE, ERCP and temporary internal stenting, together with percutaneous drainage of intra-abdominal or intrahepatic bile collections, represents a safe and effective strategy for the management of complications following both blunt and penetrating he
Therapeutic angiography for giant bleeding gastro-duodenal artery pseudoaneurysm
Ram Elazary, Mahmoud Abu-Gazala, Avraham Schlager, Noam Shussman, Avraham I Rivkind, Allan I Bloom
World Journal of Gastroenterology , 2010,
Abstract: We present the case of an 18-year-old female transferred to our center from an outside hospital due to persistent gastrointestinal bleeding. Two weeks prior to her transfer she underwent duodenal omentopexy for a perforated duodenal peptic ulcer. The patient underwent a computed tomography angiogram which identified the source of bleeding as a giant gastro-duodenal artery (GDA) pseudoaneurysm. The patient was taken to interventional radiology where successful microcoil embolization was performed. We present this rare case of a giant GDA pseudoaneurysm together with imaging and a review of the medical literature regarding prevalence, etiology and treatment options for visceral arterial aneurysms.
Thermalization of Squeezed States
Allan I. Solomon
Physics , 2005, DOI: 10.1088/1464-4266/7/12/015
Abstract: Starting with a thermal squeezed state defined as a conventional thermal state based on an appropriate hamiltonian, we show how an important physical property, the signal-to-noise ratio, is degraded, and propose a simple model of thermalization (Kraus thermalization).
Why highly expressed proteins evolve slowly
D. Allan Drummond,Jesse D. Bloom,Christoph Adami,Claus O. Wilke,Frances H. Arnold
Quantitative Biology , 2005, DOI: 10.1073/pnas.0504070102
Abstract: Much recent work has explored molecular and population-genetic constraints on the rate of protein sequence evolution. The best predictor of evolutionary rate is expression level, for reasons which have remained unexplained. Here, we hypothesize that selection to reduce the burden of protein misfolding will favor protein sequences with increased robustness to translational missense errors. Pressure for translational robustness increases with expression level and constrains sequence evolution. Using several sequenced yeast genomes, global expression and protein abundance data, and sets of paralogs traceable to an ancient whole-genome duplication in yeast, we rule out several confounding effects and show that expression level explains roughly half the variation in Saccharomyces cerevisiae protein evolutionary rates. We examine causes for expression's dominant role and find that genome-wide tests favor the translational robustness explanation over existing hypotheses that invoke constraints on function or translational efficiency. Our results suggest that proteins evolve at rates largely unrelated to their functions, and can explain why highly expressed proteins evolve slowly across the tree of life.
Optimal Signal-to-Quantum Noise Ratio for Nonclassical Number States
Yinqi Feng,Allan I. Solomon
Physics , 1997, DOI: 10.1016/S0030-4018(98)00202-8
Abstract: We analyze the properties of nonclassical number states, specifically squeezed number states D(a)S(z)|n >, and find their maximum signal-to-quantum noise ratio. It is shown that the optimal signal-to-quantum noise ratio for these states decreases as 1/(2n+1)2, where n is the photon number, from the optimal value as derived by Yuen.
Kerr cat states from the four-photon Jaynes-Cummings model
Hongchen Fu,Allan I Solomon
Physics , 2001, DOI: 10.1080/09500340110072936
Abstract: We investigate the dynamics of a four-photon Jaynes-Cummings model for large photon number. It is shown that at certain times the cavity field is in a pure state which is a superposition of two Kerr states, analogous to the Schr\"{o}dinger cat state (superposition of two coherent states) which occurs in the one and two photon cases.
Thermodynamic Prediction of Protein Neutrality
Jesse D. Bloom,Jonathan J. Silberg,Claus O. Wilke,D. Allan Drummond,Christoph Adami,Frances H. Arnold
Quantitative Biology , 2004, DOI: 10.1073/pnas.0406744102
Abstract: We present a simple theory that uses thermodynamic parameters to predict the probability that a protein retains the wildtype structure after one or more random amino acid substitutions. Our theory predicts that for large numbers of substitutions the probability that a protein retains its structure will decline exponentially with the number of substitutions, with the severity of this decline determined by properties of the structure. Our theory also predicts that a protein can gain extra robustness to the first few substitutions by increasing its thermodynamic stability. We validate our theory with simulations on lattice protein models and by showing that it quantitatively predicts previously published experimental measurements on subtilisin and our own measurements on variants of TEM1 beta-lactamase. Our work unifies observations about the clustering of functional proteins in sequence space, and provides a basis for interpreting the response of proteins to substitutions in protein engineering applications.
Bohm-Aharonov type effects in dissipative atomic systems
Allan I. Solomon,Sonia G. Schirmer
Physics , 2005,
Abstract: A state in quantum mechanics is defined as a positive operator of norm 1. For finite systems, this may be thought of as a positive matrix of trace 1. This constraint of positivity imposes severe restrictions on the allowed evolution of such a state. From the mathematical viewpoint, we describe the two forms of standard dynamical equations - global (Kraus) and local (Lindblad) - and show how each of these gives rise to a semi-group description of the evolution. We then look at specific examples from atomic systems, involving 3-level systems for simplicity, and show how these mathematical constraints give rise to non-intuitive physical phenomena, reminiscent of Bohm-Aharonov effects. In particular, we show that for a multi-level atomic system it is generally impossible to isolate the levels, and this leads to observable effects on the population relaxation and decoherence.
Pairwise entanglement in the XX model with a magnetic impurity
Hongchen Fu,Allan I Solomon,Xiaoguang Wang
Physics , 2002, DOI: 10.1088/0305-4470/35/19/310
Abstract: For a 3-qubit Heisenberg model in a uniform magnetic field, the pairwise thermal entanglement of any two sites is identical due to the exchange symmetry of sites. In this paper we consider the effect of a non-uniform magnetic field on the Heisenberg model, modeling a magnetic impurity on one site. Since pairwise entanglement is calculated by tracing out one of the three sites, the entanglement clearly depends on which site the impurity is located. When the impurity is located on the site which is traced out, that is, when it acts as an external field of the pair, the entanglement can be enhanced to the maximal value 1; while when the field acts on a site of the pair the corresponding concurrence can only be increased from 1/3 to 2/3.
Page 1 /90093
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.