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1.
J. F. Trotter J. Campsen T. Bak M. Wachs L. Forman G. Everson I. Kam 《American journal of transplantation》2006,6(8):1882-1889
The purpose of this study is to determine the role of liver biopsy and outcome of patients undergoing donor evaluation for adult-to-adult right hepatic lobe living donor liver transplantation (LDLT). Records of patients presenting for a comprehensive donor evaluation between 1997 and February 2005 were reviewed. Liver biopsy was performed only in patients with risk factors for abnormal histology. Two hundred and sixty patients underwent a comprehensive donor evaluation and 116 of 260 (45%) were suitable for donation, 14 of 260 (5.4%) did not complete evaluation and 130 of 260 (50%) were rejected. Four patients underwent unsuccessful hepatectomy surgery due to discovery of intraoperative abnormalities. Between 1997 and 2001, the acceptance rate of donor candidates (63%) was higher than 2002-2005 (36%), p < 0.0001. Sixty-six of the 150 eligible patients (44%) fulfilled criteria for liver biopsy and 28 of 66 (42%) had an abnormal finding. Less than half of the patients undergoing donor evaluation were suitable donors and the donor acceptance rate has declined over time. A large proportion of the patients undergoing liver biopsy have abnormal findings. Our evaluation process failed to identify 4 of 103 who had aborted donor surgeries. 相似文献
2.
PURPOSE: Concern over stigma as a consequence of genetic testing has grown in response to the recent increase in genetic research and testing resulting from the Human Genome Project. However, whether a genetic or hereditary basis necessarily confers a stigma to a condition remains unexamined. METHODS: We performed a qualitative interview study with 86 individuals with one of four conditions: deafness or hearing loss, breast cancer, sickle cell disease, and cystic fibrosis. The first two groups were divided approximately between people who ascribed their conditions to a genetic or hereditary cause and those who did not. RESULTS: Respondents interpreted genetic or hereditary causes and nongenetic causes in a variety of ways. Subjects with breast cancer reported the most consistently negative interpretation of genetic cause. This response concerned future ill health, not an enduring sense of stigma. Deaf and hard of hearing subjects provided the most consistently positive comments about a genetic or hereditary basis to their condition, casting familial hearing loss as a vital component of group and individual identity. Respondents with sickle cell disease and cystic fibrosis offered similar and positive interpretations of the genetic cause of their condition insofar as it meant their conditions were not contagious. CONCLUSIONS: Although some subjects report feeling stigmatized as a result of their condition, this stigmatization is not uniformly associated with the condition's cause, genetic or otherwise. Instead, stigma emerges from a variety of sources in the context of the lived experience of a particular condition. 相似文献
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4.
Anticoagulant drugs are known to have an effect on tumour growth. However, the mechanisms by which they act are poorly understood, and have therefore been investigated in this study. Wistar rats were given eight weekly subcutaneous injections of azoxymethane, at a dose of 10 mg kg-1 week-1. Following this they were randomized into two groups: a control group, which received no further treatment, and a warfarin treated group, which received warfarin at 'non-therapeutic' doses in their drinking water, for a further 8 weeks. Pairs of rats from each group were killed at 5-weekly intervals from 10 to 35 weeks after the first azoxymethane injection. At 40 weeks all remaining rats were killed. Samples of colonic mucosa from the descending colon and rectum were taken for scanning electron microscopy. The number of microadenomas per low power field was determined in both groups at each time interval. Tumour incidence and distribution were noted in animals killed at 40 weeks. The median number of microadenomas was significantly lower in warfarin treated animals than in controls at all time intervals. Tumour number was also significantly decreased by warfarin treatment (27 in azoxymethane treated animals, 10 in animals receiving azoxymethane and warfarin, P less than 0.05). The distribution of tumours along the colon was similar to that seen previously, following 12 weeks of azoxymethane. These effects occurred despite the non-concurrent administration of azoxymethane and warfarin. 相似文献
5.
M. Jung E. Krämer M. Grzenkowski K. Tang W. Blakemore A. Aguzzi K. Khazaie K. Chlichlia G. von Blankenfeld H. Kettenmann J. Trotter 《The European journal of neuroscience》1995,7(6):1245-1265
Replication-defective retroviruses expressing the t- neu oncogene, or a hybrid protein with the neu tyrosine kinase linked to the external region of the human epidermal growth factor receptor ( egfr-neu ), were used to establish lines of murine oligodendroglial precursor cells. Differentiation of the t- neu lines into myelin-associated glycoprotein (MAG)-positive oligodendrocytes was induced by dibutyryl cAMP, and the egfr-neu line showed limited differentiation in vitro upon withdrawal of epidermal growth factor. Cerebellar granule cell neurons expressed mitogens for the cell lines. Upon transplantation into demyelinated lesions, t- neu line cells engaged with the demyelinated axons whereas the egfr-neu line cells differentiated further and ensheathed the axons. These cell lines thus interact with neurons in vitro and in vivo and can be used as tools to define the molecules involved in different stages of neuron-glia interaction. 相似文献
6.
7.
J. F. Trotter J. Olson J. Lefkowitz A. D. Smith R. Arjal J. Kenison 《American journal of transplantation》2007,7(6):1624-1628
Priority for liver transplantation is based on the Model for Endstage Liver Disease (MELD) score, a mathematical function which includes international normalized ratio (INR). We present an analysis to determine the lab-to-lab variation in INR at 14 clinical laboratories across the United States. We performed a survey to identify representative clinical laboratories across the United States, where INR was measured in the determination of MELD score. Five 'standard' samples for INR were formulated and were sent to the 14 clinical laboratories to determine variation in INR and MELD score. Among the 14 clinical laboratories, the range in INR for the five samples was: sample 1 (1.2-2.0), sample 2 (1.4-2.5), sample 3 (1.7-3.4), sample 4 (1.9-3.7) and sample 5 (2.4-5.1). The range in calculated MELD score was: sample 1 (8-14), sample 2 (10-17), sample 3 (12-20), sample 4 (14-21) and sample 5 (16-25). The selection of the clinical laboratory used to determine INR may result in substantial changes in MELD score independent of severity-of-illness. These data suggest that further review of interlaboratory variation in MELD should be undertaken because of the potential impact on prioritization for liver transplantation. 相似文献
8.
Ron Shapiro James B. Young Edgar L. Milford James F. Trotter Rami T. Bustami Alan B. Leichtman 《American journal of transplantation》2005,5(4P2):874-886
Immunosuppression trends for solid organ transplantation have undergone a perceptible shift over the past decade. This period is of interest because it was during this time that the Food and Drug Administration (FDA) expanded the variety of medications to allow for alternatives in immunosuppressive management. An organ-by-organ review of SRTR data identifies several important trends. Antibody induction continues to be used for the majority of kidney (70%) , simultaneous pancreas-kidney (SPK, 79%) pancreas after kidney (PAK, 74%), and intestine recipients (74%). It is used for under half of thoracic organ recipients and remains uncommon for liver transplant recipients (20%). The type of antibody preparation utilized has shifted from muromonab-CD3 and horse ATG to rabbit ATG and monoclonal anti-IL-2 receptor antagonists. Calcineurin inhibitors continue to be used for maintenance immunosuppression for most recipients, although there has been a shift from cyclosporine to tacrolimus. A clear transition is apparent in the choice of antimetabolite from azathioprine to mycophenolate mofetil. Although corticosteroids continue to be used as maintenance immunosuppression for most recipients prior to discharge, there is evidence that efforts of steroid avoidance protocols are having an impact across all organs, as slight decreases in their use have been observed. 相似文献
9.
Marion Jung EvaMaria Krämer Thomas Müller Horst Antonicek Jacqueline Trotter 《The European journal of neuroscience》1998,10(10):3246-3256
The immortalization of progenitor cells from embryonic murine hippocampus using oncogene‐carrying retroviral vectors is described. Use of a vector encoding the oncogene v‐myc results in lines of nestin‐positive progenitor cells. Limited differentiation ensues if the cells are cultured in the presence of dibutyryl cyclic adenosine monophosphate. In contrast, use of a vector in which the extracellular portion of the epidermal growth factor (EGF) receptor is fused to the neu tyrosine kinase generates lines of pluripotential nestin‐positive progenitor cells, which differentiate upon withdrawal of EGF into neurons and glia. Differentiated neurons expressing action potentials and neurotransmitter receptors make up a high proportion of the cells. These cell lines are useful tools to investigate the characteristics of differentiating neurons and glia, as well as to screen neuroactive drugs. This work has been reported in preliminary form as an abstract (1996 Society for Neuroscience Abstract, #606.20, p. 1537). 相似文献
10.
We performed a longitudinal analysis of serum interleukin-2 (IL-2) and soluble IL-2 (sIL-2R) concentrations in 60 patients with relapsing-remitting (R-R) multiple sclerosis (MS) as well as in 33 age- and sex-matched normal controls. Overall, we found that serum IL-2 levels remained low (less than 10 U/ml) and did not change appreciably over time; however, marked fluctuations in sIL-2R levels were observed in both the patient and control groups. Using patients as their own controls, we calculated an interrelapse (disease stable) mean sIL-2R concentration as a baseline for comparison with relapse values; sIL-2R levels greater than the 90th percentile of the Student's t distribution of stable values were defined as "peaks." There were a total of 27 sIL-2R peaks, eight (30%) of which correlated with clinical relapses but were potentially predictive of only 18% (8/45) of all the recorded clinical relapses. There was no difference in disease severity (Expanded Disability Status Scale) score between peak-correlated and noncorrelated relapses. Our data suggest that despite reports of elevated levels of IL-2 and sIL-2R in MS, neither may be a useful marker for predicting clinical disease activity in R-R MS. 相似文献