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91.
Pathophysiology of Myocardial Infarction   总被引:1,自引:0,他引:1  
Skyschally A  Schulz R  Heusch G 《Herz》2008,33(2):88-100
One or several short cycles of ischemia/reperfusion before (preconditioning) or after (postconditioning) a sustained coronary occlusion with subsequent reperfusion reduce the ultimate infarct size. The protection is potent, but limited to a narrow time frame. In animal experiments, a complex signal transduction cascade was identified which results specifically in a reduction of reperfusion injury. There is evidence for both ischemic pre- and postconditioning in patients with coronary artery disease.  相似文献   
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Twelve patients underwent an osteosynthesis with titanium to treat upper and lower jaw fractures. Six to 12 months later, the miniplates were removed. Tissue samples were analyzed by light and electron microscopy for detection of a metallosis. The analysis showed new bone formation like callus tissue around the miniplates. In some cases small, rounded deposits and accumulation of colloid-like particles located next to bigger titanium artifacts were detected in the cytoplasm of histiocytes and in the matrix of connective tissue. The titanium was identified by elemental analysis using EDX in SEM as well as by EELS and electron diffraction in TEM. Both kinds of particles contain titanium, but they seem to be different in composition and derivation. The bigger particles seem to consist of metallic titanium and sourced by working on the metallic implants during the implantation itself. On the other hand, the colloidal-like, small, rounded particles in tissue macrophages and outside the cells in the matrix of connective tissue are presumably of other origin; for example, they could be derived from biodegradation and chemical conversion of the metallic implants. The titanium miniplates were examined before and after implantation by using ESCA technique and revealed metallic titanium and different compositions with other elements. The amount of titanium load of the tissue was very low in most cases and presumably not of biomedical relevance.  相似文献   
93.
Most balanced chromosomal aberrations are not associated with a clinical phenotype, however, in some patients they may disrupt gene structure. With the development of various next-generation sequencing techniques, fast and specific analyses of the breakpoint regions of chromosomal rearrangements are possible. Here, we report on a 19-year-old woman with a de novo balanced translocation t(2;8)(p13.2;q22.1) and a severe clinical phenotype including intellectual disability, epilepsy, behavioral features resembling autism, and minor dysmorphic features. By next-generation sequencing, we defined the breakpoints and found disruption of the exocyst complex component 6B (EXOC6B) gene in intron 1 on chromosome 2p13.2 involving two Alu elements with a homology of 81%. No gene was found at the respective breakpoint on chromosome 8. Expression analysis of the EXOC6B in blood lymphocytes and buccal smear revealed reduced expression in the patient in comparison with the control. Our findings in combination with one recently published case and one other patient listed in DECIPHER v5.1 indicate EXOC6B as a gene relevant for intellectual development and electrophysiological stability.  相似文献   
94.
Population studies indicate that astigmatism decreases from the corneal center toward the periphery. A standard toric intraocular lens (IOL) with a constant cylinder power cannot correct uniformly across this gradient. We built an astigmatic eye model based on corneal topography data. A progressive-toric lens with gradually decreasing cylinder power was compared with an identically designed lens but featuring conventional astigmatism correction. Residual astigmatism did not differ significantly (P=0.06) at 3 mm, and the Strehl ratio was identical for both lenses (0.51 ±0.15, P=0.88). At 5 mm, the progressive IOL yielded significantly lower residual astigmatism by 0.10 D (P<0.001). The Strehl ratio was 0.30 ±0.08 with the progressive and 0.29 ±0.08 with the standard lens (P<0.001). At 3 mm, the optical performance was comparable for both IOLs. However, at 5 mm, the progressive-toric was more effective in correcting astigmatism, and it yielded reduced residual astigmatism compared to a standard toric lens.  相似文献   
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Graft rinse prior reperfusion in liver transplantation (LT) is believed to reduce the incidence of postreperfusion syndrome and improve clinical outcome. A MEDLINE search was performed to obtain a comprehensive review of the published literature dealing with graft rinse in LT. Moreover, all thirty‐four LT centers in the Eurotransplant (ET) region were invited to participate in an online survey to whether or not graft rinse is performed and whether further research in the field is needed. Seventeen reports have been found to investigate graft rinse protocols in 1894 LT recipients. Eighteen of the thirty centers that participated in the online survey performed graft rinse prior reperfusion in LT. The most commonly used rinse solution was albumin. Nineteen centers stated interest in participating in a multicenter RCT in the field. The published literature does not provide concluding appraisal of the benefit of graft rinse in LT. Graft rinse protocols are not standardized and are based on personal experience. Appropriately designed clinical trials addressing the topic are demanded. The online survey appears to be a helpful tool for the evaluation of clinical practice and future research topics in the transplant community.  相似文献   
100.
AIMS: We investigated the value of a novel early biomarker, heart-type fatty acid-binding protein (H-FABP), in risk stratification of patients with acute pulmonary embolism (PE). METHODS AND RESULTS: We prospectively included 107 consecutive patients with confirmed PE. The endpoints were (i) PE-related death or major complications and (ii) overall 30-day mortality. Overall, 29 patients (27%) had abnormal (>6 ng/mL) H-FABP levels at presentation. Of those, 12 (41%) had a complicated course, whereas all patients with normal baseline H-FABP had a favourable 30-day outcome (OR, 71.45; P<0.0001). At multivariable analysis, H-FABP (P<0.0001), but not cardiac troponin T (P=0.13) or N-terminal pro-brain natriuretic peptide (P=0.36), predicted an adverse outcome. Evaluation of a strategy combining biomarker testing with echocardiography revealed that patients with a negative H-FABP test had an excellent prognosis regardless of echocardiographic findings. In contrast, patients with a positive H-FABP test had a complication rate of 23.1% even in the presence of a normal echocardiogram, and this rose to 57.1% if echocardiography also demonstrated right ventricular dysfunction (OR vs. a negative H-FABP test, 5.6 and 81.4, respectively). CONCLUSION: H-FABP is a promising early indicator of right ventricular injury and dysfunction in acute PE. It may help optimize risk stratification algorithms and treatment strategies.  相似文献   
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