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131.
Analysis of exercise-induced R wave amplitude changes in detection of coronary artery disease in asymptomatic men with left bundle branch block 总被引:1,自引:0,他引:1
Gregory S. Uhl USAF MC Major J.Andrew C. Hopkirk MRCP RAF Squadron Leader 《The American journal of cardiology》1979,44(7):1247-1250
The exercise electrocardiograms of 44 asymptomatic men with acquired left bundle branch block were analyzed for changes in R wave amplitude. Results were correlated with findings on selective coronary angiography. There were two subgroups: 7 men with significant angiographic coronary artery disease (Group I) and 37 with normal coronary angiograms (Group II). Exercise induced an increase in R wave amplitude in all seven men with coronary artery disease but in only 10 of the 37 men without significant coronary artery disease. This criterion thus had a sensitivity of 100 percent but a poor specificity of 73 percent, a predictive value of 41 percent and an accuracy rate of 77 percent for the diagnosis of coronary artery disease. The greater the increase in R wave amplitude the greater was the likelihood of some degree of left ventricular dysfunction as measured by wall motion abnormalities and elevated left ventricular end-diastolic pressure. The increase in R wave amplitude with exercise appears to be a sensitive test in identifying coronary artery disease in asymptomatic men with acquired left bundle branch block. 相似文献
132.
Heterozygous familial or sporadic GATA2 mutations cause a multifaceted disorder, encompassing susceptibility to infection, pulmonary dysfunction, autoimmunity, lymphoedema and malignancy. Although often healthy in childhood, carriers of defective GATA2 alleles develop progressive loss of mononuclear cells (dendritic cells, monocytes, B and Natural Killer lymphocytes), elevated FLT3 ligand, and a 90% risk of clinical complications, including progression to myelodysplastic syndrome (MDS) by 60 years of age. Premature death may occur from childhood due to infection, pulmonary dysfunction, solid malignancy and MDS/acute myeloid leukaemia. GATA2 mutations include frameshifts, amino acid substitutions, insertions and deletions scattered throughout the gene but concentrated in the region encoding the two zinc finger domains. Mutations appear to cause haplo‐insufficiency, which is known to impair haematopoietic stem cell survival in animal models. Management includes genetic counselling, prevention of infection, cancer surveillance, haematopoietic monitoring and, ultimately, stem cell transplantation upon the development of MDS or another life‐threatening complication. 相似文献
133.
Dickinson JD Smith LM Sanger WG Zhou G Townley P Lynch JC Pavletic ZS Bierman PJ Joshi SS 《British journal of haematology》2005,128(4):460-471
Chromosome abnormalities influence prognosis and tumour progression in B-cell Chronic Lymphocytic Leukaemia (CLL). This study sought to determine whether these different disease subgroups were associated with unique gene expression patterns. Thirty-four cases of CLL were screened for the 11q23, 13q14, 17p13 deletions, and trisomy 12 by fluorescence in situ hybridization (FISH). Expression of 205 cell signalling and apoptosis genes were compared by cDNA array among cases with different chromosome abnormalities. A majority of the statistically differentially expressed genes were present in the 11q23 deletion group by hierarchical clustering. CDC2, a serine/threonine kinase, was overexpressed in the 11q23 deletion group (P = 0.0004) and confirmed by Taqman real-time polymerase chain reaction. Several other genes associated with cell signalling were overexpressed in the 11q23 deletion group. A strong overall correlation existed between the presence of different chromosome abnormalities and a number of prognostic factors including immunoglobulin heavy chain variable region mutation status (P = 0.011), time to treatment (P = 0.025) and lymphocyte doubling time (P = 0.034). This study confirmed the prognostic impact of chromosome abnormalities identified by FISH in CLL, particularly the 11q23 deletion and trisomy 12. In addition, the 11q23 deletion group was associated with a unique gene expression pattern involving cell signalling and apoptosis genes. 相似文献
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Greenwood JP Maredia N Younger JF Brown JM Nixon J Everett CC Bijsterveld P Ridgway JP Radjenovic A Dickinson CJ Ball SG Plein S 《Lancet》2012,379(9814):453-460
137.
Cerebrospinal fluid repair after dural disruption is critical in preventing morbidity and mortality in trauma and cancer patients. Among reconstructive options, coverage with the temporalis muscle has been a staple in many surgeons' armamentarium. However, the donor-site morbidity has been a major drawback in the use of this technique. Here, we present our method of split, temporalis harvest for anterior cranial base reconstruction, which seeks to regain dural integrity, while maintaining aesthetic and functional elements of the donor site. We present 2 patients, demonstrating the ease of harvest, fulfillment of both cosmetic and reconstructive goals, widespread applicability, and versatility of our split, temporalis muscle flap. 相似文献
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Pearce KF Lee SJ Haagenson M Petersdorf EW Norden J Collin MP Klein JP Spellman SR Lowerson SA Davies S Dickinson AM 《Haematologica》2012,97(7):1014-1019