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41.
In the search for double-coding DNA-systems, three new pyrimidine nucleosides, each coded with an additional nucleobase anchored to the major groove face, are synthesized. Two of these building blocks carry a thymine at the 5-position of 2′-deoxyuridine through a methylene linker and a triazolomethylene linker, respectively. The third building block carries an adenine at the 6-position of pyrrolo-2′-deoxycytidine through a methylene linker. These double-headed nucleosides are introduced into oligonucleotides and their effects on the thermal stabilities of duplexes are studied. All studied double-headed nucleotide monomers reduce the thermal stability of the modified duplexes, which is partially compensated by using consecutive incorporations of the modified monomers or by flanking the new double-headed analogs with members of our former series containing propyne linkers. Also their potential in triplex-forming oligonucleotides is studied for two of the new double-headed nucleotides as well as the series of analogs with propyne linkers. The most stable triplexes are obtained with single incorporations of additional pyrimidine nucleobases connected via the propyne linker.  相似文献   
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目的:探讨Cook双球囊联合改良B-Lynch缝合术对产后出血的治疗效果。方法:选取2015年6月~2018年6月在我院经剖宫产术分娩并发生产后出血的产妇81例进行回顾性分析。根据术中止血方法的不同分为两组,对照组40例采用Cook双球囊进行止血,观察组41例在对照组的基础上应用改良B-Lynch缝合术进行止血。对两组患者的手术相关指标、止血成功率、子宫切除率、术后恢复情况和并发症发生情况进行比较。结果:观察组的术中出血量、术后24 h出血量和输血量显著低于对照组(P0.05),止血时间显著短于对照组(P0.05);观察组患者的止血成功率显著高于对照组(P0.05),子宫切除率和切口恢复时间显著低于对照组(P0.05),两组患者的住院时间和并发症发生率比较无统计学差异(P0.05)。结论:Cook双球囊联合改良B-Lynch缝合术对剖宫产产后出血患者的临床效果显著优于单用Cook双球囊,且安全性较高。  相似文献   
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In this paper a complete design of a high speed optical motion analyzer system has been described. The main core of the image processing unit has been implemented by the differential algorithm procedure. Some intelligent and conservative procedures that facilitate the search algorithm have also been proposed and implemented for the processing of human motions. Moreover, an optimized modified direct linear transformation (MDLT) method has been used to reconstruct 3D markers positions which are used for deriving kinematic characteristics of the motion. Consequently, a set of complete tests using some simple mechanical devices were conducted to verify the system outputs. Considering the system verification for human motion analysis, we used the system for gait analysis and the results including joint angles showed good compatibility with other investigations. Furthermore, a sport application example of the system has been quantitatively presented and discussed for Iranian National Karate-kas. The low computational cost, the high precision in detecting and reconstructing marker position with 2.39 mm error, and the capability of capturing from any number of cameras to increase the domain of operation of the subject, has made the proposed method a reliable approach for real-time human motion analysis. No special environment limitation, portability, low cost hardware and built in units for simulations and kinematic analysis are the other significant specifications of this system.  相似文献   
45.
Adsorption techniques are widely used to remove industrial wastewater contaminants, especially non-biodegradable colourants. In this study, Iranian zeolite clinoptilolite was synthesised using magnetic iron oxide as an inexpensive and efficient adsorbent. The results showed that using natural zeolite, the removal efficiency of 26.8.6% at pH?=?3 reached 48% at pH?=?9. However, the adsorption capacity of the modified clinoptilolite did not change by increasing pH; it ranged from 96.4% to 98.6%. Moreover, increase in the initial concentration of the dye did not have any effects on the removal efficacy of the modified clinoptilolite. Using natural zeolite, on the other hand, the adsorption capacity showed a significant decrease and reached less than 10% at the 200?mg/l dye concentration. At the optimal contact time of 45?min, the dye removal rate by the modified zeolite was more than 98% at the optimal dose of 0.5?g. Indeed, the adsorption isotherm complied with Freundlich equation. Overall, the results showed that in comparison to the natural zeolite, the adsorption capacity of the clinoptilolite modified by iron nanoparticles increased significantly due to the uniformity of the cavities and increase in the surface of the adsorbent.  相似文献   
46.
Cadherins are homophilic cell-to-cell adhesion molecules that help cells respond to environmental changes. Newly formed cadherin junctions are associated with increased cell phosphorylation, but the pathways driving this signaling response are largely unknown. Since cadherins have no intrinsic signaling activity, this phosphorylation must occur through interactions with other signaling molecules. We previously reported that cadherin-11 engagement activates joint synovial fibroblasts, promoting inflammatory and degradative pathways important in rheumatoid arthritis (RA) pathogenesis. Our objective in this study was to discover interacting partners that mediate cadherin-11 signaling. Protein array screening showed that cadherin-11 extracellular binding domains linked to an Fc domain (cad11Fc) induced platelet-derived growth factor (PDGFR)-α phosphorylation in synovial fibroblasts and glioblastoma cells. PDGFRs are growth factor receptor tyrosine kinases that promote cell proliferation, survival, and migration in mesodermally derived cells. Increased PDGFR activity is implicated in RA pathology and associates with poor prognosis in several cancers, including sarcoma and glioblastoma. PDGFRα activation by cadherin-11 signaling promoted fibroblast proliferation, a signaling pathway independent from cadherin-11-stimulated IL-6 or matrix metalloproteinase (MMP)-3 release. PDGFRα phosphorylation mediated most of the cad11Fc-induced phosphatidyl-3-kinase (PI3K)/Akt activation, but only part of the mitogen-activated protein kinase (MAPK) response. PDGFRα-dependent signaling did not require cell cadherin-11 expression. Rather, cad11Fc immunoprecipitated PDGFRα, indicating a direct interaction between cadherin-11 and PDGFRα extracellular domains. This study is the first to report an interaction between cadherin-11 and PDGFRα and adds to our growing understanding that cadherin-growth factor receptor interactions help balance the interplay between tissue growth and adhesion.  相似文献   
47.
A convenient preparative synthesis of 2-amino-2-deoxyuridine was developed. Starting from 2-amino-2-deoxyuridine and 2-amino-2-deoxycytidine, monomers for the phosphoamidite oligonucleotide synthesis were obtained that carry a linker with methoxyoxalamide groups in position 2.  相似文献   
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Candida antarctica B lipase-catalysed alcoholysis of 2, 3, 5-tri-O-hexanoyluridine (1a), 2, 3, 5-tri-O-dodecanoyluridine (1b), 2, 3, 5-tri-O-hexanoylinosine (1c) and 2, 3, 5-tri-O-dodecanoylinosine (1d) proceeded regioselectively to produce the corresponding 2, 3-di-O-acylribonucleosides 2a–d, providing a simple and efficient access to these new lipophilic compounds. Contrasting to the alcoholysis, enzymatic hydrolysis of 1a–d using different enzymes and experimental conditions did not proceed regioselectively.  相似文献   
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