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31.
The development of a goitre in the retrosternal space may result in many different symptoms due to local compression. We describe a case in which such a goitre resulted in full-thickness ulceration of the oesophagus, which presented as a fatal haematemesis. We believe that such a complication has not been previously reported. 相似文献
32.
In view of the current audiological need to obtain rapidly recorded and objective threshold information, particularly for frequencies below 1 kHz, we have developed an evoked potential technique based on the frequency following response. The technique involves the acquisition of a single captured epoch of EEG containing phase-locked responses to 1000 cycles of a continuous pure-tone stimulus. The captured epoch is partitioned into segments representing the responses to single cycles of the stimulus. The segments are then averaged to produce the period evoked potential. The process takes less than five seconds. 相似文献
33.
34.
A T Lefor P Vuocolo F B Parker L F Sillin 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(10):1225-30; discussion 1231
Pancreatic complications following cardiopulmonary bypass are infrequent but are associated with high mortality. All cases of pancreatic complications following cardiopulmonary bypass from 1972 to 1987 at a single institution were retrospectively reviewed. Of 5621 patients who underwent cardiopulmonary bypass, 25 (0.44%) sustained pancreatic complications. There were 15 cases of acute pancreatitis and 10 cases of pancreatic necrosis, with 11 deaths in the group reviewed, a mortality rate of 44%. Factors that were correlated with mortality associated with pancreatic complications in this study include preoperative hypotension, preoperative use of inotropic agents, and renal failure (preoperative and postoperative). Factors that have been previously associated with mortality from pancreatic complications in other studies, such as fluid sequestration, respiratory failure, sepsis, tachycardia, hypocalcemia, age greater than 55 years, and abnormal laboratory findings, were not found to be significantly associated with mortality in this study. Of the five patients for whom complete data were available, not one patient received greater than 800 mg of calcium per square meter of body surface area in the perioperative period. While the exact mechanism of pancreatic injury remains unclear, based on experimental studies and clinical correlation, it is likely that pancreatic ischemia remains a significant contributing factor. We conclude that no factor specifically associated with cardiopulmonary bypass was correlated significantly with mortality. 相似文献
35.
Lara Kevorkian David A. Young Clare Darrah Simon T. Donell Lee Shepstone Sarah Porter Sarah Brockbank Dylan R. Edwards rew E. Parker Ian M. Clark 《International journal of experimental pathology》2004,85(1):A23-A23
Objective To profile the expression of all known members of the matrix metalloproteinase ( MMP ), a disintegrin and metalloproteinase with thrombospondin motifs ( ADAMTS ), and tissue inhibitor of metalloproteinases ( TIMP s) gene families in normal cartilage and that from patients with osteoarthritis (OA).
Methods Human cartilage was obtained from femoral heads at joint replacement for either osteoarthritis or following fracture to the neck of femur. Total RNA was purified and expression of genes assayed using quantitative real-time PCR.
Results Several members of the above gene families were regulated in OA. Genes increasing in expression in OA were: at P < 0.001, MMP-13 , MMP-28 , ADAMTS-16 ; at P < 0.01, MMP-9 , MMP-16 , ADAMTS-2 , ADAMTS-14 and at P < 0.05, MMP-2 , TIMP-3 , ADAMTS-12 . Genes decreasing in expression in OA were: at P < 0.001, MMP-1 , MMP-3 , ADAMTS-1 ; at P < 0.01, MMP-10 , TIMP-1 , ADAMTS-9 and at P < 0.05, TIMP-4 , ADAMTS-5 , ADAMTS-15 . Correlation analysis revealed that groups of genes across the gene families are co-expressed in cartilage.
Conclusion This is the first comprehensive expression profile of all known MMP , ADAMTS and TIMP genes in cartilage. Patterns of expression provide a foundation on which to understand mechanisms of gene regulation in OA and potentially for refining the specificity of anti-proteolytic therapies. 相似文献
Methods Human cartilage was obtained from femoral heads at joint replacement for either osteoarthritis or following fracture to the neck of femur. Total RNA was purified and expression of genes assayed using quantitative real-time PCR.
Results Several members of the above gene families were regulated in OA. Genes increasing in expression in OA were: at P < 0.001, MMP-13 , MMP-28 , ADAMTS-16 ; at P < 0.01, MMP-9 , MMP-16 , ADAMTS-2 , ADAMTS-14 and at P < 0.05, MMP-2 , TIMP-3 , ADAMTS-12 . Genes decreasing in expression in OA were: at P < 0.001, MMP-1 , MMP-3 , ADAMTS-1 ; at P < 0.01, MMP-10 , TIMP-1 , ADAMTS-9 and at P < 0.05, TIMP-4 , ADAMTS-5 , ADAMTS-15 . Correlation analysis revealed that groups of genes across the gene families are co-expressed in cartilage.
Conclusion This is the first comprehensive expression profile of all known MMP , ADAMTS and TIMP genes in cartilage. Patterns of expression provide a foundation on which to understand mechanisms of gene regulation in OA and potentially for refining the specificity of anti-proteolytic therapies. 相似文献
36.
R. Parker Ward MD Mouaz H. Al-Mallah MD Gabriel B. Grossman MD PhD Christopher L. Hansen MD Robert C. Hendel MD Todd C. Kerwin MD Benjamin D. McCallister Jr MD Rupa Mehta MD Donna M. Polk MD MPH Peter L. Tilkemeier MD Aseem Vashist MD Kim Allan Williams MD David G. Wolinsky MD Edward P. Ficaro PhD 《Journal of nuclear cardiology》2007,14(6):911-e38
37.
R. Parker Ward Mouaz H. Al-Mallah Gabriel B. Grossman Christopher L. Hansen Robert C. Hendel Todd C. Kerwin Benjamin D. McCallister Rupa Mehta Donna M. Polk Peter L. Tilkemeier Aseem Vashist Kim Allan Williams David G. Wolinsky Edward P. Ficaro 《Journal of nuclear cardiology》2007,14(6):e26-e38
Conclusion The ACCF/ASNC AC for SPECT MPI provides recommendations for the appropriate use of SPECT MPI. After the publication of the
AC document in 2005, the AC has been used by nuclear cardiology practices with many clinical studies evaluating the list of
indications in routine clinical practice. From these data. ASNC recommends minor but important changes to the indication list,
suggesting the addition of 6 new indications and the modification of the definitions for “chest pain syndrome” and “CHD high
risk.”. An objective review of existing indications focused on only those indications that had significant variability among
the reviewers (n=20). These indications were reviewed in the presence of existing and new evidence-based data, and ASNC recommends
that the grades for 6 indications be re-evaluated.
The AC for SPECT MPI will require periodic review as new evidence becomes available or as clinical practice evolves. ASNC
recognizes the importance of these criteria to improve the quality of patient care, and it will continue to play a key role
in assembling the information for this ongoing review. From the current summary of evidence, ASNC consensus opinions, and
ASNC recommendations in this document, ASNC strongly recommends that the AC guidelines be reviewed
Prepared by the American Society of Nuclear Cardiology Quality Assurance Subcommittee for Quality in Imaging Standards.
Reviewed by members of the American Society of Nuclear Cardiology Quality Assurance Committee.
Approved by the American Society of Nuclear Cardiology Board of Directors, September 6, 20. 相似文献
38.
Matthew P Smelley Daniel E Virnich Kim A Williams R Parker Ward 《Journal of nuclear cardiology》2007,14(4):537-543
BACKGROUND: A hypertensive response to exercise (HRE) is associated with false-positive stress echocardiograms and myocardial perfusion single photon emission computed tomography (myocardial perfusion imaging [MPI]) defects even in the absence of coronary artery disease (CAD). Transient ischemic dilation (TID) of the left ventricle on stress MPI is a marker of severe CAD and future cardiac events. This study evaluated the association between an HRE and TID. METHODS AND RESULTS: Blinded quantitative TID assessment was performed in 125 patients who had an HRE and a summed stress score (SSS) of less than 4, as well as 125 control patients with an SSS of less than 4 and without an HRE matched for age, gender, and resting systolic blood pressure. Cardiac comorbidities, pretest Framingham risk, and exercise results were recorded. TID was defined as a stress-to-rest volume ratio of 1.22 or greater. An HRE was associated with a high prevalence of TID and significantly more TID than no HRE (25.6% vs 11.2%; odds ratio, 3.00 [95% confidence interval, 1.41-6.38]). TID was more prevalent even in subgroups with a low pretest probability CAD, including those without diabetes mellitus or angina. On conditional logistic regression analysis, an HRE was found to be independently associated with TID after consideration of other clinical and exercise MPI variables (odds ratio, 2.72 [95% confidence interval, 1.01-7.31]). CONCLUSION: An HRE is associated with a high prevalence of TID in patients without other significant perfusion defects, possibly as a result of global subendocardial ischemia induced by the HRE. 相似文献
39.
40.
The effectiveness of scalp hypothermia in preventing cyclophosphamide-induced alopecia 总被引:2,自引:0,他引:2
R Parker 《Oncology nursing forum》1987,14(6):49-53