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991.
This Classic article is a reprint of the original work by R. Merle d’Aubigné and M. Postel, Functional Results of Hip Arthroplasty with Acrylic Prosthesis. An accompanying biographical sketch on R. Merle d’Aubigné, MD, is available at DOI  10.1007/s11999-008-0571-2. The Classic Article is ©1954 by the Journal of Bone and Joint Surgery, Inc. and is reprinted with permission from Merle d’Aubigné R, Postel M. Functional results of hip arthroplasty with acrylic prosthesis. J Bone Joint Surg Am. 1954;35:451--475.  相似文献   
992.

Background

Prediction of prognosis after liver transplantation (OLT) remains difficult. The present study determines if standard laboratory parameters measured within the first week after OLT correlate with outcome.

Patients and Methods

Laboratory parameters measured within the first weak after OLT of 328 patients were grouped either graft loss or death within 90 days after (group 1: graft loss; group 2: death; group 3: neither graft loss nor death within 90 days).

Results

Peak AST and ALT were significantly lower in group 3 (1867 and 1252 U/L) than in group 1 (4474 and 2077 U/L) or 2 (3121 and 1865 U/L). Bilirubin was significantly lower and γ-GT significantly higher in group 3 compared to groups 1 and 2. In multivariate analysis, high AST peaks were independently associated with death or graft loss within 90 days. An increase in γ-GT and low bilirubin early after transplantation were found to be independently associated with superior outcome.

Discussion

Unexpectedly, a disproportionate rise in γ-GT was associated with graft and patient survival of more than 90 days. This might be explained by regeneration phenomena in the liver indicative of a well functioning graft.  相似文献   
993.
994.
SPG4/SPAST, the gene-encoding spastin, is responsible for the most frequent form of autosomal dominant hereditary spastic paraplegia (HSP). SPG4-HSP is a heterogeneous disorder characterized by both interfamilial and intrafamilial variation, especially regarding the severity and the age at onset. In this study, we investigated the origin of the mutation and the factors involved in intra-familial heterogeneity in a family with a SPG4 mutation. We demonstrated that the mutation occurred de novo and show evidence of somatic mosaicism in the grandfather, who was the only affected member of six siblings. His disease began at age 55, much later than in his daughter, who had onset at age 18, and his grandson, in whom onset was at age 5. These observations indicate that de novo mutations can occur in SPG4, and that somatic mosaicism might account for intra-familial variation in SPG4-linked HSP.  相似文献   
995.
Systems biology approaches for toxicology   总被引:3,自引:0,他引:3  
Systems biology/toxicology involves the iterative and integrative study of perturbations by chemicals and other stressors of gene and protein expression that are linked firmly to toxicological outcome. In this review, the value of systems biology to enhance the understanding of complex biological processes such as neurodegeneration in the developing brain is explored. Exposure of the developing mammal to NMDA (N-methyl-D-aspartate) receptor antagonists perturbs the endogenous NMDA receptor system and results in enhanced neuronal cell death. It is proposed that continuous blockade of NMDA receptors in the developing brain by NMDA antagonists such as ketamine (a dissociative anesthetic) causes a compensatory up-regulation of NMDA receptors, which makes the neurons bearing these receptors subsequently more vulnerable (e.g. after ketamine washout), to the excitotoxic effects of endogenous glutamate: the up-regulation of NMDA receptors allows for the accumulation of toxic levels of intracellular Ca(2+) under normal physiological conditions. Systems biology, as applied to toxicology, provides a framework in which information can be arranged in the form of a biological model. In our ketamine model, for example, blockade of NMDA receptor up-regulation by the co-administration of antisense oligonucleotides that specifically target NMDA receptor NR1 subunit mRNA, dramatically diminishes ketamine-induced cell death. Preliminary gene expression data support the role of apoptosis as a mode of action of ketamine-induced neurotoxicity. In addition, ketamine-induced cell death is also prevented by the inhibition of NF-kappaB translocation into the nucleus. This process is known to respond to changes in the redox state of the cytoplasm and has been shown to respond to NMDA-induced cellular stress. Although comprehensive gene expression/proteomic studies and mathematical modeling remain to be carried out, biological models have been established in an iterative manner to allow for the confirmation of biological pathways underlying NMDA antagonist-induced cell death in the developing nonhuman primate and rodent. Published in 2007 John Wiley & Sons, Ltd.  相似文献   
996.
997.
BACKGROUND AND AIMS: Stress is often perceived by patients with inflammatory bowel disease (IBD) as the leading cause of their disease. The aim of this study was to assess whether stress, evaluated through life event (LE) occurrence, is associated with IBD onset. METHODS: Incident cases of IBD, including 167 patients with Crohn's disease (CD) and 74 with ulcerative colitis (UC), were compared with two control groups, one of 69 patients with acute self-limited colitis (ASLC) and another of 255 blood donors (BDs). Stress was assessed using Paykel's self-questionnaire of LEs. Only LEs occurring within 6 months before the onset of symptoms in IBD cases and ASLC controls and before blood donation in BD controls were registered. Anxiety and depression were assessed using Bate's and Beck's questionnaires, respectively. RESULTS: In univariate analysis, occurrence of LEs was more frequent in the 6-month period prior to diagnosis in CD cases than in UC cases or either control group. After adjustment for depression and anxiety scores as well as other characteristics such as smoking status and sociodemographic features, this association appeared no longer significant. No associations were noted between occurrence of LEs and onset of UC relative to controls. CONCLUSIONS: Despite its separate association with CD, LE occurrence does not appear to be an independent risk factor for IBD onset.  相似文献   
998.
Since its introduction in 1996, the Genesis II Total Knee System has produced good clinical results in patients undergoing primary total knee replacement. A systematic review of the literature-the first of its kind for this device-was undertaken to collect data on the Genesis II in order to provide a better understanding of its medium- to long-term performance. Of 124 Genesis II-related studies published in the literature, 11 met the eligibility criteria and were included in the final analysis. The included studies had a mean follow-up length of 38.1 months. Data from 1201 knees were available for review. Patients were an average of 70.5 years of age and predominantly female (63%). Findings indicated that the revision rate with this implant is low with up to 11.9 years of follow-up, with 14 revisions in total. The survival rate ranged from 100% at 1 and 2 years to 96.0% at 11.9 years. The mean Knee Society knee score improved 51.0 points from preoperative to postoperative evaluation. In conclusion, the Genesis II exhibited good clinical performance with up to 11 years follow-up, with an encouraging rate of survival and improvement in function. Additional studies with larger sample sizes and longer follow-up periods are needed to better understand the long-term performance of this implant.  相似文献   
999.
BD FocalPoint GS? computer‐assisted screening of BD SurePath® liquid‐based cervical cytology slides (SP + FP) was compared with screening an accompanying conventional cervical Papanicolaou (Pap) smear (CON) in a split sample trial of 2,198 routine specimens. The rate of unsatisfactory specimens in the SP + FP arm was 0.2% compared with 4.1% in the conventional Pap smear, a significant reduction. There was no statistically significant difference between SP + FP and CON for the detection of histologically confirmed high‐grade (HG) lesions in the routine split sample specimens (n = 9). To further test the sensitivity of SP + FP for HG lesions, 38 SurePath slides from confirmed HG cases, without an accompanying CON, were interpolated among the routine smears. In every one of the 47 confirmed HG cases, either HG cells were present in the microscope fields selected by FocalPointGS? for review by the screening cytologist (46 of 47), or full screening of the slide was indicated by the FocalPointGS? (1 of 47), confirming the effectiveness of SP + FP technology for primary screening. In a small number of cases, the screening cytologist did not recognize the abnormality even though on review HG cells were present in fields selected by FocalPointGS?. The overall detection rate was 93% for HG squamous lesions; 89% for known HG endocervical glandular lesions; and 91% for known endometrial carcinoma. In conclusion, the SP + FP detected 100% of HG abnormalities in the trial set; significantly reduced the rate of unsatisfactory specimens; and improved the overall screening rate of detection of HG abnormalities particularly of glandular lesions when compared with other screening technologies. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
1000.
This research sought to better understand how clinical and translational research is defined and perceived by community service providers. In addition, the research sought to elicit how the perspectives of service providers may hinder or facilitate collaborative research efforts. The study employed a qualitative methodology, focus groups. A nonprobability sampling strategy was used to recruit participants from three neighborhoods in the Tufts University's catchment area. Focus group findings add to the nascent body of literature on how community partners view clinical and translational research and researchers. Findings indicate that cultural disconnects, between researchers and community partners exist, as does mistrust, all of which serve as potential barriers to community research partnerships. This paper suggests rethinking the business of community engagement in researcher, particularly as it relates to building research capacity to approach, engage, and partner with communities.  相似文献   
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