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991.
Aim: To evaluate the importance of surgical bypass between the terminal part of functional arteriovenous shunt (av) for hemodialysis on upper extremity and inner jugular vein in axillosubclavian venous segment obstruction associated with central venous hypertension. Method: Retrospective assessment of surgical bypass between central segments of av fistula and ipsilateral/contralateral inner jugular vein using ePTFE graft in 17 patients over a 20 year period (1987-2006). Results: The surgical procedure was not associated with intra- or post-operative complications. Primary cumulative bypass and av fistula function persisted for 26 months on average. Conclusion: An accurate bypass to salvage the functional dialysis access associated with central venous hypertension requires careful decision based on clinical and radiological examination. The bypass procedure is beneficial where endovascular treatment is not indicated. Clinical and radiological bypass monitoring is crucial.  相似文献   
992.
Background: Midazolam is a frequently used benzodiazepine in anaesthesiology and intensive care. Aim: The aim of pilot study was to monitor its effect during heart perfusion in the laboratory rat. Methods: The same groups of animals (n = 10). The 1(st) group was treated with midazolam in a dose of 0.5mg/kg i.p. The 2(nd) group was a placebo. After i.p. administration of heparine injection of 500 IU dose, the hearts were excised and perfused (modified Langendorf's method). Working schedule: stabilization/ischaemia/reperfusion proceed at intervals of 20/30/60 min. Monitored parameters in isolated heart: left ventricle pressure (LVP), end-diastolic pressure (LVEDP), contractility (+dP/dt(max)). Results: The treated hearts showed improved postischemic recovery, reaching LVP values of 92 +/- 6 % at the end of the reperfusion, placebo only 61 +/- 7 %. In placebo hearts LVEDP rose from 10.0 +/- 0.5 mmHg to 43 +/- 4 mmHg after, in treated animals only about 25 mmHg. The treated hearts improved +dP/dt(max) recovery during reperfusion to 91 +/- 8 %. These values were significantly greater than those obtained from the placebo hearts. Conclusions: Positive changes in monitored parameters were found in this experimental pilot study. We conclude that the administration of midazolam in laboratory rats has a cardioprotective potential against ischemia-reperfusion induced injury.  相似文献   
993.
Aims: the presented study is aimed at the evaluation of correlation of free light chains serum levels - kappa, lambda and their relation (K/L ratio) and serum levels of selected biological markers in a group of patients with multiple myeloma examined at the time of the diagnosis. Methods: 102 patients with multiple myeloma were included in this prospective study. Free light chains serum levels were determined by Freelite Binding Site system, for determination of serum levels of selected parameters the following methods were used: REA thymidinekinase (TK), RIA (beta(2)microglobulin (beta(2)m), ICTP, PINP), enzymoimmunoassay (sIL-6R, sVCAM-1, sICAM-1, sOPG) and quantitative enzymatic immunoassay (sHGF, sVEGF, sSyndecan-1 (sSyn-1) a sFas). Results: There was found a correlation in the kappa-group of the dominant kappa chain and serum readings of beta(2)m (r = 0.344, p = 0.005), TK (r = 0.263, p = 0.035), ICTP (r = 0.402, p = 0.001), PINP (r = 0.264, p = 0.039), sOPG (r = 0.328, p = 0.028), sSyn-1 (r = 0.255, p = 0.046) and sFas (r = 0.418, p = 0.001). In case of K/L ratio there was found a statistically significant association of levels of beta(2)m (r = 0.316, p = 0.01), TK (r = 0.274, p = 0.027), ICTP (r = 0.346, p = 0.006), PINP (r = 0.261, p = 0.042), sSyn-1 (r = 0.283, p = 0.026) and sFas (r = 0.377, p = 0.002). In the lambda-group the analysis confirmed mutual dependence of the dominant lambda chain levels on beta(2)m (r = 0.476, p = 0.003), ICTP (r = 0.375, p = 0.022), sVCAM-1 (r = 0.383, p = 0.019), sHGF (r = 0.441, p = 0.006) and sFas (r = 0.334, p = 0.040). In addition we ascertained a correlation of L/K ratio and levels of beta(2)m (r = -0.473, p = 0.003), TK (r = -0.412, p = 0.011), ICTP (r = -0.331, p = 0.045), PINP (r = -0.409, p = 0.012), sHGF (r = -0.357, p = 0.028), sSyn-1 (r = -0.449, p = 0.005) a sFas (r = - 0.371, p = 0.022). Conclusions: The study confirmed mutual correlation of FLC serum levels and the levels of several selected biological markers, in particular beta(2)m, TK, ICTP, PINP, sSyn-1 a sFas at time of the diagnosis. It referred to the mutual relation of bone marrow microenvironment, biological qualities of clonal plasmocytes and the intensity of the free light chains production by the tumour cell population.  相似文献   
994.
995.
Initial BRCA1 and BRCA2 analyses conducted in breast and ovarian cancer families were focused on identification of mutations in coding sequences and splicing sites of the genes. Large genomic rearrangements as well as mutations in promoter or untranslated regions have been missed by standard detection strategies. Nevertheless, in Western countries, a detailed study of families with strong linkage to BRCA1 identified large genomic deletions and rearrangements in this gene as early as 1997. To date, no such gene alteration has been described in Central and Eastern European populations. In our study of BRCA1/2 genes in the Czech population, we have detected a complex genomic rearrangement in BRCA1 using RNA-based analysis for mutation screening. This rearrangement involves exons 21 and 22 and results in a protein product lacking BRCT domain important for its function.  相似文献   
996.

Background  

One of the goals of global metabolomic analysis is to identify metabolic markers that are hidden within a large background of data originating from high-throughput analytical measurements. Metabolite-based clustering is an unsupervised approach for marker identification based on grouping similar concentration profiles of putative metabolites. A major problem of this approach is that in general there is no prior information about an adequate number of clusters.  相似文献   
997.
The seasonal dynamics of a community of endomycorrhizal fungal morphotypes in the roots of three grassland species (Achillea millefolium, Poa angustifolia, Plantago lanceolata) was evaluated, together with the effects of experimental treatment (mowing and phosphorus application) and the host plant properties. Strong seasonal variability was found in the fungal community, where clear seasonal patterns can be distinguished for several fungal morphotypes. The sampling date explained 20 to 30% of the total compositional variability for all three host species. ThePlantago roots host the highest number of arbuscular mycorrhizal (AM) fungal populations. There are two co-dominant fungal morphotypes inAchillea roots (assigned to the generaScutellospora andGlomus) and only one strongly dominant morphotype (assigned toGlomus), in thePoa roots. All three host species have a comparable pattern of richness of AM morphotypes with a single peak in the summer, possibly aligned with the flowering time of the host.  相似文献   
998.
999.
Streptococcus milleri group (SMG) is a group of three streptococcal species (S. anginosus, intermedius and constellatus) that act as opportunist pathogens, among others in cystic fibrosis. Due to their fastidious character, they are both difficult to cultivate and to differentiate from less pathogenic streptococcal species, therefore being most probably underdiagnosed. Semi-selective McKay agar and NAS agar were developed to facilitate SMG recovery from clinical samples; however, direct comparison of recovery rates has not been published yet. We tested the performance of both media on 123 patient samples and demonstrated general superiority of NAS agar for SMG recovery during primary cultivation convincingly. This observation was also confirmed by quantitative drop tests during subculture. Despite the undisputed overall superiority of NAS agar over McKay agar, a smaller fraction of strains grew better on McKay agar. Inter-strain differences were the most probable explanation. Therefore, when economic conditions are not limiting and maximum recovery rate is desirable, both plates are advised to be used in parallel for primary cultivation of clinical samples.  相似文献   
1000.
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