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81.
82.
This study examined (1) the effect of the accelerated seed ageing on cucumber germination with treatments: Bacillus subtilis QST713 or Pseudomonas fluorescens CA in 1% methylcellulose and fungicides difenoconazole, carboxin or pyraclostrobin in 5% polyvinyl alcohol, and (2) the impact on disease severity of gummy stem blight (GSB) caused by Didymella bryoniae by the seed treatments and foliar spray application of methylcellulose-formulated B. subtilis or P. fluorescens. Difenoconazole, pyraclostrobin and microorganisms suppressed growth of D. bryoniae in a laboratory dual culture; carboxin had no effect on D. bryoniae growth. Germination of fungicide-treated seed was unaffected by accelerated seed ageing. Greenhouse: GSB disease severity with PVA and non-treated seed was 89% and 84%, respectively, whereas, difenoconazole, carboxin and pyraclostrobin, was significantly reduced, 56%, 53% and 40%, respectively. Germination of Bacillus-treated seed was unaffected by accelerated seed ageing, but was significantly reduced with Pseudomonas-treated seed. GSB disease severity with B. subtilis or P. fluorescens-treated seed was inconsistent; however, foliar spray application of B. subtilis significantly reduced GSB. Accelerated seed ageing exposed a significant negative impact on seed germination with P. fluorescens. Based on the accelerated ageing test, P. fluorescens-treated cucumber seed is detrimental to seed survival and therefore, is not a candidate for biocontrol activities for cucumber requiring seed storage.  相似文献   
83.
Fibronectin molecules are dimers composed of subunits whose primary structures may differ. This is due to alternative splicing in at least two regions (ED and IIICS) of the pre-mRNA. Using two monoclonal antibodies specific for two different epitopes of domain 5 (high affinity for heparin), we have quantitatively analyzed the expression of the IIICS sequence in human fibronectins from different sources. The results demonstrated that the percentage of fibronectin subunits containing the IIICS is higher in fibronectins from tumor-derived or simian virus 40-transformed human cells than in fibronectins from human plasma or normal human fibroblasts. Furthermore, we observed that 45-65% of fibronectin subunits from transformed cells or normal embryonic fibroblasts are sialylated on the heparin-binding domain 5, whereas this occurs in only 24-28% of fibronectin subunits from normal adult fibroblasts. On the contrary, no sialylation was observed on domain 5 in fibronectin from human plasma.  相似文献   
84.
We have examined the effects of cyclosporin A (CsA) and a series of CsA analogs that bind with decreasing affinity to cyclophilin, to evaluate the involvement of this protein in the release of preformed (histamine) and de novo synthesized (peptide leukotriene C4; LTC4) mediators of inflammatory reactions from human basophils. CsA (8 to 800 nM) concentration-dependently inhibited (5 to 60%) histamine release from peripheral blood basophils challenged with anti-IgE. CsA was more potent (92.6 +/- 1.8 vs 59.1 +/- 4.5%; p less than 0.001) and, at low concentrations, more effective when the channel-operated influx of Ca2+ was bypassed by the ionophore A23187 (IC40 = 24.1 +/- 3.9 vs 105.5 +/- 22.2 nM; p less than 0.05). CsA had no effect on the release of histamine caused by phorbol myristate and bryostatin 1 that activate different isoforms of protein kinase C. Inhibition of histamine release from basophils challenged with anti-IgE was not abolished by washing (three times) the cells before anti-IgE challenge. CsA also inhibited the de novo synthesis of LTC4 from basophils challenged with anti-IgE. The inhibitory effect of CsA was very rapid, and the drug, added from 1 to 10 min during the reaction, inhibited the ongoing release of histamine caused by anti-IgE and by A23187. The experiments with CsA analogs (CsG, CsC, CsD, and CsH) showed that CsH, which has an extremely low affinity for cyclophilin, has no effect on basophil mediator release. In addition, there is a significant correlation between the concentrations of CsA, G, C, and D that inhibited by 30% the histamine release induced by anti-IgE (r = 0.99; p less than 0.001) and by A23187 (r = 0.87; p less than 0.001) and their affinity for cyclophilin.  相似文献   
85.
In connection with the liming of an acid lake in southern Norway, a series of litter bags was placed in a pH-gradient in the limed lake and a nearby unlimed lake. During the experiments, which lasted two years, no significant differences in decomposition rates between the various localities at the same depth were noticed. The chironomid collector Tanytarsus pallidicornis was the dominant invertebrate species in the benthic samples. This demonstrates the importance of fine particulate organic matter as a food source in the lake. Collector dominance was lower in the leaf packs, which consisted mostly of coarse particulate organic matter. A poor fauna of detritus grazers probably contributed to the unchanged rates of decomposition of the leaves after liming.  相似文献   
86.
87.
The Illumina Infinium HumanMethylation450 BeadChip has emerged as one of the most popular platforms for genome wide profiling of DNA methylation. While the technology is wide-spread, systematic technical biases are believed to be present in the data. For example, this array incorporates two different chemical assays, i.e., Type I and Type II probes, which exhibit different technical characteristics and potentially complicate the computational and statistical analysis. Several normalization methods have been introduced recently to adjust for possible biases. However, there is considerable debate within the field on which normalization procedure should be used and indeed whether normalization is even necessary. Yet despite the importance of the question, there has been little comprehensive comparison of normalization methods. We sought to systematically compare several popular normalization approaches using the Norwegian Mother and Child Cohort Study (MoBa) methylation data set and the technical replicates analyzed with it as a case study. We assessed both the reproducibility between technical replicates following normalization and the effect of normalization on association analysis. Results indicate that the raw data are already highly reproducible, some normalization approaches can slightly improve reproducibility, but other normalization approaches may introduce more variability into the data. Results also suggest that differences in association analysis after applying different normalizations are not large when the signal is strong, but when the signal is more modest, different normalizations can yield very different numbers of findings that meet a weaker statistical significance threshold. Overall, our work provides useful, objective assessment of the effectiveness of key normalization methods.  相似文献   
88.
The best option for the treatment of a failing heart is heart transplantation. The transplantation program at the University Hospital Center Rebro Zagreb started in 1988. To the best of our knowledge this is the first retrospective study on cardiac transplantation in Croatia looking into survival following heart transplantation. Between 1988 and 2006, we performed 81 heart transplantations at the University Hospital Center Rebro Zagreb. Our study focused on the last ten years after establishment of the Department of cardiac surgery as a separate institution. There were thirteen different hospitals throughout Croatia, which contributed to the donor network. Average age of the heart recipient was 48+/-11.8 years (range 14-72), and average age of the heart donor was 34+/-10.7 years (range 14-56). There were more women among the heart donors (34%) then among the heart recipients (18%). During the first ten years, from 1988-1998, the average number of cardiac transplantations was 3 per year In the period from 1998-2006, average number of cardiac transplantations increased to 6 per year. The average thirty-day mortality for the last nine years was 27%. It declined from 30% and 40% in 1998 and 1999, respectively down to 0% in the last two years. Average age of the patients who died was 50+/-6.5years (range 44-62) and did not significantly differ from those who survived. The donor network has grown up to fourteen different hospitals throughout Croatia. The limiting factor in cardiac transplant surgery is the number of available donors. Therefore in attempt to form a good transplant program it is crucial to form an efficient donor network. The number of performed cardiac transplantations is expected to rise until it reaches the number of available donors. With advances in operative technique and postoperative management--immunosuppressive therapy we have observed a remarkable drop in the early operative mortality in the studied period.  相似文献   
89.
90.
It was shown previously that Ea4-peptide of trout pro-IGF-I exerted mitogenic activity in non-transformed cells and inhibited colony formation in a soft agar medium of established human cancer cells. Here we report that the same peptide inhibits the invasion of human breast cancer cells (MDA-MB-231) through a matrigel membrane in a dose-dependent manner. The expression of urokinase-type plasminogen activator (uPA), tissue-type plasminogen activator (tPA) and plasminogen activator inhibitor 1 (PAI1) genes in MDA-MB-231 cells were downregulated by treatment with rtEa4-peptide. The inhibition of expression of these genes in response to rtEa4-peptide treatment was reduced to the control level when inhibitors for c-Jun N-terminal kinase 1/2 (JNK1/2), mitogen activated protein kinase kinase 1/2 (Mek1/2), p38 mitogen activated protein kinase (p38 MAPK), phosphatidylinositol 3-kinase (PI3K), and phosphokinase C (PKC) were used. These results suggest that inhibition of invasion of MDA-MB-231 cells by rtEa4-peptide may be mediated via the suppression of uPA, tPA, and PAI1 gene activities through signal transduction pathways.  相似文献   
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