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41.
Betty B. Wray Claude A. Harmon Elisabeth J. Rushing Richard J. Cole 《Journal of cancer research and clinical oncology》1982,103(2):181-185
Summary Serum samples from 121 patients in whom malignant disease had been diagnosed, were assayed for precipitins to fungal isolates from leukemia-associated environments. Control sera were from age-, sex-, and race-matched patients with no history of malignant disease. Sera from 36 (30%) malignancy patients and seven (6%) controls yielded a precipitin band to an aflatoxin-producing Aspergillus flavus isolate from a leukemia-associated house 2, p<0.05%). No significant numbers of precipitins were obtained to either of the other fungal isolates from that and another such house.Although A. fumigatus has frequently been incriminated as a source of infection in patients with malignancy, only 9% of malignancy patients had a precipitin response to it, as did 1.6% of controls. Also, the presence of the precipitins to A. flavus was not connected with past radiation or imunosuppressive therapy. However, among patients with precipitins to A. fumigatus there was a higher death rate in the year following the study. Precipitins to A. flavus may be related to heavy environmental exposure possibly leading to aflatoxin exposure which may contribute to development of malignancy through immunosuppressive effects. 相似文献
42.
Dr. Linda Rabeneck MD MPH Nelda P. Wray MD MPH Nancy J. Petersen MS 《Journal of general internal medicine》1996,11(5):287-293
OBJECTIVE: Percutaneous endoscopic gastrostomy (PEG) tube placement is the preferred method for long-term enteral feeding of patients
who are unable to take food by mouth. Despite the widespread acceptance of the procedure, no large-scale study of the long-term
outcomes of patients receiving PEG tubes has been reported. The objective of this study was to determine the survival of patients
in whom PEG tubes are placed.
DESIGN: Retrospective cohort study using data obtained from two computerized databases.
SETTING: Department of Veterans Affairs hospitals.
PATIENTS: Seven thousand three hundred sixty-nine patients who received a PEG tube in fiscal years 1990 through 1992.
RESULTS: For the 7,369 patients, the mean age was 68.1 years and 98.6% were men. PEG tubes were most commonly placed in patients with
cerebrovascular disease (18.9%), other organic neurologic disease (28.6%), or head and neck cancer (15.7%). Although the complication
rate of the procedure itself was low (4%), because of the severity of their underlying disease, 1,732 patients (23.5%) died
during the hospitalization in which the PEG tube was placed. The median survival of the full cohort was 7.5 months.
CONCLUSIONS: This study documents the widespread placement of PEG tubes in severely ill patients, half of whom are in the terminal phase
of their illness. Further study is needed to determine whether these patients benefit from PEG tube placement in terms of
their quality of life and survival.
From the Department of Veterans Affairs Health Services Research and Development (HSR&D) Field Program, and the Department
of Medicine, Baylor College of Medicine, Houston, Tex.
Supported by the Department of Veterans Affairs Health Services Research and Development Houston Field Program.
Presented at the 95th annual meeting of the American Gastroenterological Association, New Orleans, La., May 15–18, 1994. 相似文献
43.
Cameron RA Mahairas G Rast JP Martinez P Biondi TR Swartzell S Wallace JC Poustka AJ Livingston BT Wray GA Ettensohn CA Lehrach H Britten RJ Davidson EH Hood L 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(17):9514-9518
Results of a first-stage Sea Urchin Genome Project are summarized here. The species chosen was Strongylocentrotus purpuratus, a research model of major importance in developmental and molecular biology. A virtual map of the genome was constructed by sequencing the ends of 76,020 bacterial artificial chromosome (BAC) recombinants (average length, 125 kb). The BAC-end sequence tag connectors (STCs) occur an average of 10 kb apart, and, together with restriction digest patterns recorded for the same BAC clones, they provide immediate access to contigs of several hundred kilobases surrounding any gene of interest. The STCs survey >5% of the genome and provide the estimate that this genome contains approximately 27,350 protein-coding genes. The frequency distribution and canonical sequences of all middle and highly repetitive sequence families in the genome were obtained from the STCs as well. The 500-kb Hox gene complex of this species is being sequenced in its entirety. In addition, arrayed cDNA libraries of >10(5) clones each were constructed from every major stage of embryogenesis, several individual cell types, and adult tissues and are available to the community. The accumulated STC data and an expanding expressed sequence tag database (at present including >12, 000 sequences) have been reported to GenBank and are accessible on public web sites. 相似文献
44.
Binding to chromosomes of herpes simplex-related antigens in biochemically transformed cells. 总被引:1,自引:0,他引:1 下载免费PDF全文
S Kit M Kurchak W Wray D R Dubbs 《Proceedings of the National Academy of Sciences of the United States of America》1978,75(7):3288-3291
Association of herpes simplex virus (HSV)-related antigens with chromosomes was demonstrated in human and mouse cells biochemically transformed by HSV that had been irradiated with ultraviolet light. This was accomplished by using peroxidase-anti-peroxidase immunological staining with rabbit antisera that had high neutralizing titers against both HSV-specific thymidine kinase activity and virus infectivity. Antisera-against HSV did not react with chromosomes of uninfected cells nor did normal sera react with any of the constitutents of biochemically transformed cells. Methanol/acetic acid treatment of biochemically transformed cells eliminated their nuclear staining for HSV-related antigens. In vitro binding of HSV-related antigens to chromosomes was demonstrated by incubating soluble antigens from high salt extracts of HSV-infected cells with methanol/acetic acid-fixed chromosomes of biochemically transformed or uninfected cells, followed by exposure to antiserum against HSV and peroxidase-anti-peroxidase staining. There was no staining when soluble extracts from uninfected cells were substituted for those from HSV-infected cells. The results show that cells biochemically transformed and lytically infected by HSV, respectively, contain antigens, which like the Epstein-Barr virus-associated nuclear antigen (EBNA), bind to chromosomes in vivo and in vitro. 相似文献
45.
Surprisingly high prevalence of anxiety and depression in chronic breathing disorders 总被引:7,自引:0,他引:7
STUDY OBJECTIVES: The objectives of this study were to assess the prevalence, screening, and recognition of depression and anxiety in persons with chronic breathing disorders, including COPD. DESIGN: Cross-sectional study. SETTING: The Michael E. DeBakey Veterans Affairs Medical Center (MEDVAMC). PARTICIPANTS: A large sample of 1,334 persons with chronic breathing disorder diagnoses who received care at the MEDVAMC. MEASUREMENTS: The prevalence of anxiety and depression was measured in a large sample of persons with a chronic breathing disorder diagnosis who received care at the MEDVAMC, using the Primary Care Evaluation of Mental Disorders (PRIME-MD) screening questions. The positive predictive value of the PRIME-MD questions was then determined. The prevalence of anxiety and depressive diagnoses in patients determined to have COPD was then measured, using the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (SCID). RESULTS: Of patients screened with the PRIME-MD, 80% screened positive for depression, anxiety, or both. The predictive value of a positive phone screen for either depression or anxiety was estimated to be 80%. In the subsample of patients who had COPD and received a diagnosis using the SCID, 65% received an anxiety and/or depressive disorder diagnosis. Of those patients, only 31% were receiving treatment for depression and/or anxiety. CONCLUSIONS: It is troubling that a mere 31% of COPD patients with depression or anxiety are being treated, particularly given their high prevalence in this population. Practical screening instruments may help increase the recognition of anxiety and depression in medical patients, as suggested by the excellent positive predictive value of the PRIME-MD in our study. 相似文献
46.
Witman MA Fjeldstad AS McDaniel J Ives SJ Zhao J Barrett-O'Keefe Z Nativi JN Stehlik J Wray DW Richardson RS 《Hypertension》2012,60(3):659-668
Using flow-mediated vasodilation (FMD), reactive hyperemia, and an acute oral antioxidant cocktail (AOC; vitamins C and E and α-lipoic acid), this study aimed to provide greater insight into altered vascular function and the role of oxidative stress in chronic heart failure patients with reduced ejection fraction (HFrEF) and at several time points beyond heart transplantation (HTx). A total of 61 age-matched subjects (12 healthy controls, 14 New York Heart Association class II and III HFrEF, and 35 HTx recipients [<3 years post-HTx, 5-10 years post-HTx, and >14 years post-HTx]) ingested either placebo (PL) or an AOC before FMD and reactive hyperemia testing of the brachial artery. Vascular function, as measured by FMD, was not different among the controls (6.8±1.9%), recent <3-year post-HTx group (8.1±1.2%), and the 5- to 10-year post-HTx group (5.5±1.0%). However, PL FMD was lower in the HFrEF (4.5±0.7%) and in the >14-year post-HTx group (2.9±0.8%). The AOC increased plasma ascorbate levels in all of the groups but only increased FMD in the controls (PL, 6.8±1.9%; AOC, 9.2±1.0%) and >14-year post-HTx recipients (PL, 2.9±0.8%; AOC, 4.5±1.3%). There were no differences in reactive hyperemia in any of the groups with PL or AOC. This cross-sectional study reveals that, compared with controls, vascular function is blunted in HFrEF, is similar soon after HTx, but is decreased with greater time post-HTx with free radicals implicated in this progression. 相似文献
47.
E M Byrne T Carrillo-Roa A K Henders L Bowdler A F McRae A C Heath N G Martin G W Montgomery L Krause N R Wray 《Translational psychiatry》2013,3(6):e269
Our understanding of major depressive disorder (MDD) has focused on the influence of genetic variation and environmental risk factors. Growing evidence suggests the additional role of epigenetic mechanisms influencing susceptibility for complex traits. DNA sequence within discordant monozygotic twin (MZT) pairs is virtually identical; thus, they represent a powerful design for studying the contribution of epigenetic factors to disease liability. The aim of this study was to investigate whether specific methylation profiles in white blood cells could contribute to the aetiology of MDD. Participants were drawn from the Queensland Twin Registry and comprised 12 MZT pairs discordant for MDD and 12 MZT pairs concordant for no MDD and low neuroticism. Bisulphite treatment and genome-wide interrogation of differentially methylated CpG sites using the Illumina Human Methylation 450 BeadChip were performed in WBC-derived DNA. No overall difference in mean global methylation between cases and their unaffected co-twins was found; however, the differences in females was significant (P=0.005). The difference in variance across all probes between affected and unaffected twins was highly significant (P<2.2 × 10−16), with 52.4% of probes having higher variance in cases (binomial P-value<2.2 × 10−16). No significant differences in methylation were observed between discordant MZT pairs and their matched concordant MZT (permutation minimum P=0.11) at any individual probe. Larger samples are likely to be needed to identify true associations between methylation differences at specific CpG sites. 相似文献
48.
49.
50.
C. Wray J. C. Scovotti J. Tobis C. U. Niemann R. Planinsic A. Walia J. Findlay G. Wagener J. B. Cywinski D. Markovic C. Hughes A. Humar A. Olmos R. Sierra R. Busuttil R. H. Steadman 《American journal of transplantation》2013,13(1):184-191
Over the last decade the age of liver transplant (LT) recipients and the likelihood of coronary artery disease (CAD) in this population have increased. There are no multicenter studies that have examined the impact of CAD on LT outcomes. In this historical cohort study, we identified adult LT recipients who underwent angiography prior to transplantation at seven institutions over a 12‐year period. For each patient we recorded demographic data, recipient and donor risk factors, duration of follow‐up, the presence of angiographically proven obstructive CAD (≥50% stenosis) and post‐LT survival. Obstructive CAD was present in 151 of 630 patients, the CAD(+) group. Nonobstructive CAD was found in 479 patients, the CAD(?) group. Patient survival was similar for the CAD(+) group (adjusted HR 1.13, CI = [0.79, 1.62], p = 0.493) compared to the CAD(?) group. The CAD(+) patients were further stratified into severe (CADsev, >70% stenosis, n = 96), and moderate CAD (CADmod, 50–70% stenosis, n = 55) groups. Survival for the CADsev (adjusted HR = 1.26, CI = [0.83, 1.91], p = 0.277) and CADmod (adjusted HR = 0.93, CI = [0.52, 1.66], p = 0.797) groups were similar to the CAD(?) group. We conclude that when current CAD treatment strategies are employed prior to transplant, post‐LT survival is not significantly different between patients with and without obstructive CAD. 相似文献