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排序方式: 共有4063条查询结果,搜索用时 15 毫秒
91.
Brian Kornblit David G. Maloney Barry E. Storer Michael B. Maris Lars Vindel?v Parameswaran Hari Amelia A. Langston Michael A. Pulsipher Wolfgang A. Bethge Thomas R. Chauncey Thoralf Lange Finn B. Petersen Kai Hübel Ann E. Woolfrey Mary E.D. Flowers Rainer Storb Brenda M. Sandmaier 《Haematologica》2014,99(10):1624-1631
The study is a randomized phase II trial investigating graft-versus-host disease prophylaxis after non-myeloablative (90 mg/m2 fludarabine and 2 Gy total body irradiation) human leukocyte antigen matched unrelated donor transplantation. Patients were randomized as follows: arm 1 – tacrolimus 180 days and mycophenolate mofetil 95 days (n=69); arm 2 – tacrolimus 150 days and mycophenolate mofetil 180 days (n=71); arm 3 – tacrolimus 150 days, mycophenolate mofetil 180 days and sirolimus 80 days (n=68). All patients had sustained engraftment. Grade II-IV acute graft-versus-host disease rates in the 3 arms were 64%, 48% and 47% at Day 150, respectively (arm 3 vs. arm 1 (hazard ratio 0.62; P=0.04). Owing to the decreased incidence of acute graft-versus-host disease, systemic steroid use was lower at Day 150 in arm 3 (32% vs. 55% in arm 1 and 49% in arm 2; overall P=0.009 by hazard ratio analysis). The Day 150 incidence of cytomegalovirus reactivation was lower in arm 3 (arm 1, 54%; arm 2, 47%; arm 3, 22%; overall P=0.002 by hazard ratio analysis). Non-relapse mortality was comparable in the three arms at two years (arm 1, 26%; arm 2, 23%; arm 3, 18%). Toxicity rates and other outcome measures were similar between the three arms. The addition of sirolimus to tacrolimus and mycophenolate mofetil is safe and associated with lower incidence of acute graft-versus-host disease and cytomegalovirus reactivation. (clinicaltrials.gov identifier: 00105001). 相似文献
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93.
Roland D. McDevitt Ph.D Amelia M. Haviland Ph.D Ryan Lore M.P.P Laura Laudenberger M.S Matthew Eisenberg Ph.D Neeraj Sood Ph.D 《Health services research》2014,49(2):609-627
Objective
To identify the degree of selection into consumer-directed health plans (CDHPs) versus traditional plans over time, and factors that influence choice and temper risk selection.Data Sources/Study Setting
Sixteen large employers offering both CDHP and traditional plans during the 2004–2007 period, more than 200,000 families.Study Design
We model CDHP choice with logistic regression; predictors include risk scores, in addition to family, choice setting, and plan characteristics. Additional models stratify by account type or single enrollee versus family.Data Collection/Extraction Methods
Risk scores, family characteristics, and enrollment decisions are derived from medical claims and enrollment files. Interviews with human resources executives provide additional data.Principal Findings
CDHP risk scores were 74 percent of traditional plan scores in the first year, and this difference declined over time. Employer contributions to accounts and employee premium savings fostered CDHP enrollment and reduced risk selection. Having to make an active choice of plan increased CDHP enrollment but also increased risk selection. Risk selection was greater for singles than families and did not differ between HRA and HSA-based CDHPs.Conclusions
Risk selection was not severe and it was well managed. Employers have effective methods to encourage CDHP enrollment and temper selection against traditional plans. 相似文献94.
Vanille J. Greiner Catherine Manin Eric Larquet Nabila Ikhelef Frédéric Gréco Sophie Naville Pierre-Emmanuel Milhiet Frédéric Ronzon Andrey Klymchenko Yves Mély 《Vaccine》2014
The aim of this work was to further understand the relationship between the immunogenicity and the structure of Hepatitis B surface antigen (HBsAg) particles used in Hepatitis B vaccines. To reach this aim, we compared by using a large range of techniques, the structure and properties of untreated particles with those of particles stored for 3 weeks at +60 °C, a treatment which resulted in a loss of HBsAg antigenicity (toward RF-1 mAb) and immunogenicity (in mice). While untreated particles imaged by electron microscopy and atomic force microscopy appeared as isolated nanoparticles of ∼ 20 nm, heated particles appeared as long chains of particle aggregates with a partial loss of their protein protrusions. Moreover, infrared spectroscopy and circular dichroism revealed that the secondary structure of the S proteins was significantly affected, with a loss of 10% of their α-helix content. Steady-state and time-resolved fluorescence data further revealed strong modifications of the most emitting Trp residues at the particle surface, confirming significant changes in the conformation of the S proteins. Moreover, modifications in the organization of both the lipid core and lipid membrane surface of the heated particles were evidenced by environment-sensitive 3-hydroxyflavone probes. Taken together, our data evidenced a clear relationship between the bona fide S protein structure and lipid organization notably at the particle surface and the particle immunogenicity. 相似文献
95.
96.
97.
Federica Cerri Luca Salvatore Danish Memon Filippo Martinelli Boneschi Marta Madaghiele Paola Brambilla Ubaldo Del Carro Carla Taveggia Nilo Riva Amelia Trimarco Ignazio D. Lopez Giancarlo Comi Stefano Pluchino Gianvito Martino Alessandro Sannino Angelo Quattrini 《Biomaterials》2014
Several bioengineering approaches have been proposed for peripheral nervous system repair, with limited results and still open questions about the underlying molecular mechanisms. We assessed the biological processes that occur after the implantation of collagen scaffold with a peculiar porous micro-structure of the wall in a rat sciatic nerve transection model compared to commercial collagen conduits and nerve crush injury using functional, histological and genome wide analyses. We demonstrated that within 60 days, our conduit had been completely substituted by a normal nerve. Gene expression analysis documented a precise sequential regulation of known genes involved in angiogenesis, Schwann cells/axons interactions and myelination, together with a selective modulation of key biological pathways for nerve morphogenesis induced by porous matrices. These data suggest that the scaffold's micro-structure profoundly influences cell behaviors and creates an instructive micro-environment to enhance nerve morphogenesis that can be exploited to improve recovery and understand the molecular differences between repair and regeneration. 相似文献
98.
Hemophagocytic Lymphohistiocytosis in Imported Pediatric Visceral Leishmaniasis in a Nonendemic Area
99.
Methamphetamine (m-AMPH) treatment produces long-lasting damage to striatal and cortical monoaminergic terminals and may also injure nonmonoaminergic cortical neurons. Evidence suggests that both dopamine (DA) and glutamate (GLU) play crucial roles in producing this damage. We used quantitative autoradiography to examine [3H]mazindol ([3H]MAZ) binding to striatal DA transporters and [3H]GLU binding to N-methyl-D-aspartate (NMDA) receptors in the striatum and cortex 1 week and 1 month after a neurotoxic regimen of m-AMPH. Rats received m-AMPH (4 mg/kg) or saline (SAL) (1 ml/kg) in four s.c. injections separated by 2 h intervals. One week after m-AMPH, the ventral and lateral sectors of the striatum showed the greatest decreases in both [3H]MAZ and [3H]GLU binding, while the nucleus accumbens (NA) showed no significant decreases. One month after m-AMPH, striatal [3H]MAZ binding was still significantly decreased, while NMDA receptor binding had recovered. Surprisingly, the parietal cortex showed a m-AMPH-induced increase in NMDA receptor binding in layers II/III and IV 1 week after m-AMPH and only in layers II/III 1 month after m-AMPH. The prefrontal cortex showed no m-AMPH-induced changes in NMDA receptor binding at either time point. This is the first demonstration that a regimen of m-AMPH that results in long-lasting damage to DA terminals can alter forebrain NMDA receptor binding. Thus, repeated m-AMPH treatments may produce changes in glutamatergic transmission in selected striatal and cortical regions. © 1996 Wiley-Liss, Inc. 相似文献
100.
Ruth Chia Sara Saez-Atienzar Natalie Murphy Adriano Chi Cornelis Blauwendraat International Myasthenia Gravis Genomics Consortium Ricardo H. Roda Pentti J. Tienari Henry J. Kaminski Roberta Ricciardi Melania Guida Anna De Rosa Loredana Petrucci Amelia Evoli Carlo Provenzano Daniel B. Drachman Bryan J. Traynor 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(5)