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排序方式: 共有1004条查询结果,搜索用时 62 毫秒
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Jens Vogel-Claussen Jan Skrok Elliot K Fishman João AC Lima Ashish S Shah David A Bluemke 《Journal of cardiothoracic surgery》2009,4(1):42-5
We report the case of a 67 year-old patient who presented with worsening chest pain and shortness of breath, four days post
acute myocardial infarction. Contrast enhanced computed tomography of the chest ruled out a pulmonary embolus but revealed
an unexpected small subepicardial aneurysm (SEA) in the lateral left ventricular wall which was confirmed on cardiac magnetic
resonance imaging. Intraoperative palpation of the left lateral wall was guided by the cardiac MRI and CT findings and confirmed
the presence of focally thinned and weakened myocardium, covered by epicardial fat. An aneurysmorrhaphy was subsequently performed
in addition to coronary bypass surgery and a mitral valve repair. The patient was discharged home on post operative day eight
in good condition and is feeling well 2 years after surgery. 相似文献
94.
AC Unger H Cabrera-Palacios AP Schulz Ch Jürgens A Paech 《European journal of medical research》2009,14(6):264-271
Introduction
At present there are no reliable non-traumatic and non-invasive methods to analyse the healing process and loosening status after total hip replacement. Therefore early as well as late loosening of prosthesis and interface component problems are difficult to be found or diagnosed at any time.Methods
In a cadaver study the potential application of Resonance Frequency Monitoring (RFM) will be evaluated as a non-invasive and non-traumatic method to monitor loosening and interface problems in hip replacement. In a 65 year old female cadaver different stability scenarios for a total hip replacement (shaft, head/modular head and cup, ESKA, Luebeck, Germany) are simulated in cemented and cement less prosthesis and then analysed with RFM. The types of stability vary from secure/press-fit to interface-shaft disruption.Results
The RFM shows in cemented as well as cement less prosthesis significant intra-individual differences in the spectral measurements with a high dynamic (20 dB difference corresponding to the factor 100 (10000%)), regarding the simulated status of stability in the prosthesis system.Conclusion
The results of the study demonstrate RFM as a highly sensitive non-invasive and non-traumatic method to support the application of RFM as a hip prosthesis monitoring procedure. The data obtained shows the possibility to use RFM for osteointegration surveillance and early detection of interface problems, but will require further evaluation in clinical and experimental studies. 相似文献95.
Vairaktaris E Papageorgiou G Derka S Moulavassili P Nkenke E Kessler P Vassiliou S Papakosta V Spyridonidou S Vylliotis A Lazaris AC Anagnostopoulou S Mourouzis C Yapijakis C Patsouris E 《Journal of cancer research and clinical oncology》2007,133(4):227-233
PURPOSE: To determine whether ras-activated cascades lead to activation of ets-1 expression in sequential histological stages of oral oncogenesis in an experimental animal model. METHODS: Thirty-seven Syrian golden hamsters were divided into three experimental groups (A, B, C) and one control group. The hamsters' buccal pouches in experimental groups were treated with 0.5% 9, 10-dimethyl-1, 2-benzanthracene (DMBA) for 14 weeks and were excised at 10, 14, 19 weeks, respectively. The biopsies were classified pathologically (normal mucosa, hyperkeratosis, hyperplasia, dysplasia, early invasion, well and moderately differentiated carcinoma) and studied immunohistochemically. The two-tailed Student's t test was performed for each animal group and for each histological category. RESULTS: The ets-1 expression increased in early stages of oral tumor formation and invasion. The expression of N-ras gradually decreased during oral oncogenesis, as previously observed with H-ras. CONCLUSIONS: Neither N-ras nor H-ras affects ets-1 expression in contrast to other types of cancer in which N-ras and ets-1 are implicated in the same signalling pathway. Therefore, the existing pathway implicating these proteins might be somehow altered in oral cancer. It seems that ets-1 is a good prognostic marker for invasiveness and progression of oral cancer. 相似文献
96.
Recombinant human butyrylcholinesterase from milk of transgenic animals to protect against organophosphate poisoning 总被引:10,自引:0,他引:10 下载免费PDF全文
Huang YJ Huang Y Baldassarre H Wang B Lazaris A Leduc M Bilodeau AS Bellemare A Côté M Herskovits P Touati M Turcotte C Valeanu L Lemée N Wilgus H Bégin I Bhatia B Rao K Neveu N Brochu E Pierson J Hockley DK Cerasoli DM Lenz DE Karatzas CN Langermann S 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(34):13603-13608
Dangerous organophosphorus (OP) compounds have been used as insecticides in agriculture and in chemical warfare. Because exposure to OP could create a danger for humans in the future, butyrylcholinesterase (BChE) has been developed for prophylaxis to these chemicals. Because it is impractical to obtain sufficient quantities of plasma BChE to treat humans exposed to OP agents, the production of recombinant BChE (rBChE) in milk of transgenic animals was investigated. Transgenic mice and goats were generated with human BChE cDNA under control of the goat beta-casein promoter. Milk from transgenic animals contained 0.1-5 g/liter of active rBChE. The plasma half-life of PEGylated, goat-derived, purified rBChE in guinea pigs was 7-fold longer than non-PEGylated dimers. The rBChE from transgenic mice was inhibited by nerve agents at a 1:1 molar ratio. Transgenic goats produced active rBChE in milk sufficient for prophylaxis of humans at risk for exposure to OP agents. 相似文献
97.
EM Maier J Pongratz AC Muntau B Liebl U Nennstiel-Ratzel U Busch R Fingerhut B Olgemöller AA Roscher W Röschinger 《Clinical genetics》2009,76(2):179-187
Medium‐chain acyl‐CoA dehydrogenase deficiency (MCADD) represents a potentially fatal fatty acid β‐oxidation disorder. Newborn screening (NBS) by tandem mass spectrometry (MS/MS) has been implemented worldwide, but is associated with unresolved questions regarding population heterogeneity, burden on healthy carriers, cut‐off policies, false‐positive and negative rates. In a retrospective case‐control study, 333 NBS samples showing borderline acylcarnitine patterns but not reaching recall criteria were genotyped for the two most common mutations (c.985A>G/c.199C>T) and compared with genotypes and acylcarnitines of 333 controls, 68 false‐positives, and 34 patients. c.985A>G was more frequently identified in the study group and false‐positives compared to controls (1:4.3/1:2.3 vs. 1:42), whereas c.199C>T was found more frequently only within the false‐positives (1:23). Biochemical criteria were devised to differentiate homozygous (c.985A>G), compound heterozygous (c.985A>G/c.199C>T), and heterozygous individuals. Four false‐negatives were identified because our initial algorithm required an elevation of octanoylcarnitine (C8) and three secondary markers in the initial and follow‐up sample. The new approach allowed a reduction of false‐positives (by defining high cut‐offs: 1.4 μmol/l for C8; 7 for C8/C12) and false‐negatives (by sequencing the ACADM gene of few suspicious samples). Our validation strategy is able to differentiate healthy carriers from patients doubling the positive predictive value (42→88%) and to target NBS to MCADD‐subsets with potentially higher risk of adverse outcome. It remains controversial, if NBS programs should aim at identifying all subsets of all diseases included. Because the natural course of milder variants cannot be assessed by observational studies, our strategy could serve as a general model for evaluation of MS/MS‐based NBS. 相似文献
98.
We evaluated the role of vascular endothelial growth factor (VEGF), placental growth factor (PlGF), and hypoxia-inducible factor 1-a (HIF1-a) in melanoma angiogenesis and investigated their expression in dysplastic nevi, as potential melanoma precursors. In addition, we examined a possible correlation of VEGF expression with PlGF and HIF1-a. These factors were detected immunohistochemically in 95 melanomas of all types and stages and in 28 dysplastic nevi. We used 10 intradermal melanocytic nevi as controls. HIF1-a was expressed in 93 out of 95 (97.89%) melanomas and in none of the dysplastic or control nevi. HIF1-a expression was more intense in melanocytes around necrotic areas but did not correlate with melanoma type, the Clark staging or the Breslow thickness. A strong positive association was detected between HIF1-a and VEGF expression in all cases. VEGF was detected in 82 out of 95 (86.31%) melanomas and in 21 out of 28 (75%) dysplastic nevi, whereas it was expressed weakly in neoplastic cells of the controls. Its expression was more intense in melanomas, especially in nodular melanomas of elevated stage and thickness. PIGF was detected in 46 out of 95 (48.42%) melanomas and in none of the nevi. Expression did not correlate with melanoma staging nor thickness; however, it was more intense in superficial spreading melanomas, where a weak positive association between VEGF and PlGF was also detected. There was no association between HIF1-a and PlGF in any melanoma type. Hypoxia, through the expression of HIF1-a, plays a key role in melanoma progression; it activates VEGF secretion, which induces angiogenesis and metastasis. The role of PlGF seems to be limited. 相似文献
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