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41.
利用二阶段相分离控制方法制备不同孔径的三维骨架聚合物及配位聚合物材料.在第一阶段的反应诱导相分离中,通过加入十二烷基苯磺酸作为相分离抑制剂,控制了环氧树脂在聚乙二醇介质中固化反应的相分离速率和程度;在第二阶段,将处于亚稳状态的聚合物用ZnSO4或CdSO4水溶液处理,在配合作用的推动下发生二次相分离,并稳定三维骨架结构,最终实现了在1~2μm范围内调节孔径大小.研究了三维连续孔道在充满二乙烯基苯高折射液体后的滤光特性,通过引入金属离子改变固体材料折射率的方法,验证了光在高折射液相中的全反射效应,并从定性角度建立三维骨架材料的孔径及分布与透射光波长范围之间的关系,对新光学现象给出了初步解释.  相似文献   
42.
This is the first ligase chain reaction used for diagnosis of spinal muscular atrophy (SMA). Universal fluorescent tri-probe ligation (UFTPL), a novel strategy used for distinguishing the multi-nucleotide alternations at single base, is developed to quantitatively analyze the SMN1/SMN2 genes in diagnosis of SMA. Ligase chain reaction was performed by adding three probes including universal fluorescent probe, connecting probe and recognizing probe to differentiate single nucleotide polymorphisms in UFTPL. Our approach was based on the two UFTPL products of survival motor neuron 1 (SMN1) and SMN2 genes (the difference of 9 mer) and analyzed by capillary electrophoresis (CE). We successfully determined various gene dosages of SMN1 and SMN2 genes in homologous or heterologous subjects. By using the UFTPL-CE method, the SMN1 and SMN2 genes were fully resolved with the resolution of 2.16 ± 0.37 (n = 3). The r values of SMN1 and SMN2 regression curves over a range of 1–4 copies were above 0.9944. Of the 48 DNA samples, the data of gene dosages were corresponding to that analyzed by conformation sensitive CE and denatured high-performance liquid chromatography (DHPLC). This technique was found to be a good methodology for quantification or determination of the relative genes having multi-nucleotide variants at single base.  相似文献   
43.
Eleven male sportsmen at the age of 24.3 ± 4.5 were examined. Their hip joint flexors and extensors were tested by an REV-9000 Technogym dynamometer system during isokinetic movements at angular velocities of 100 (low) and 200 (high) °/s. The range of hip joint movements was from 30 (in flexion) to 130° (in extension). Torque values and their ratios for hip flexors and extensors at different angular positions were obtained and compared. It is shown that, at high speeds, the flexion movement significantly raises (p < 0.001) the torque ratios of flexors and extensors in flexion positions of the hip (50 and 60°). These ratios approximately twofold exceed their values at moderate velocities. The weakness of hip joint extensors in extreme flexion positions of the hip may cause injury of this group of muscles at fast movements.  相似文献   
44.
The elastic modulus El of the crystalline regions in the direction parallel to the chain axis was measured by X-ray diffraction for polyimide derived from polyamic acid (biphthalic dianhydride and p-phenylene diamine). These specimens were cured by two different routes: curing at 200 °C, and at 400 °C for 1 h, respectively (2STEPS), and curing from 80 °C to 400 °C stepwise (nine steps) for 1 h at each step (STEPWISE). The El values of 54–169 GPa were obtained for the STEPWISE specimen and 80–178 GPa for the 2STEPS specimen, depending on the meridional reflection employed for measurement of the El value. A linear relationship between the El value and the fiber identity period was obtained from each meridional diffraction, such that the El value increased with an increase in the fiber identity period. The El value of the fully extended structure was estimated to be 210 GPa. These are considered to be due to the coexistence of polymorphs with different skeletal structures. The crystalline regions of the 2STEPS specimen seems to consist of a more extended skeleton than those of the STEPWISE specimen. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 3294–3301, 1999  相似文献   
45.
本文描述中国对虾附肢肌肉(第一步足、第五步足、第三游泳足)解剖学结构,所得结果与白对虾Penaeus setiferu:作比较,其不同之处列于表1.  相似文献   
46.
在100Hz-100MHz频率范围内,应用Agilent4294A阻抗分析仪测量了骨骼肌纤维走行与电场呈垂直方向的大鼠离体骨骼肌细胞介电谱,利用Cole—Cole图、介电损耗因子频谱、介电损耗角正切频谱等分析,建立了大鼠骨骼肌细胞介电特性数据特征.  相似文献   
47.
Objective: Many studies have demonstrated that the loss of muscle mass (LMM) poses a risk of postural instability in the elderly; however, few studies have shown how LMM decreases proprioception. In this study, we investigated the changes in postural sway among older individuals with LMM induced by application of a local vibratory stimulus. Method: We enrolled 64 older adults (mean age). Postural sway was measured while applying vibration stimuli of 30, 60, and 240 Hz to both the gastrocnemius and lumbar multifidus muscles. We also measured the relative proprioceptive weighting ratio (RPW) of postural sway. The patients were divided into LMM and non-LMM (NLMM) groups. The study subjects were compared in terms of their age, height, weight, body mass index (BMI), lower leg skeletal muscle mass index (LSMI), L4/5 lumbar multifidus cross-sectional area ratio, and RPW at 30, 60, and 240 Hz. Results: Subjects in the LMM group showed a significantly lower RPW at 60 Hz, LSMI, and BMI than did those in the NLMM group. Conclusions: Decrease in RPW with 60-Hz stimulation concerning the lower leg proprioception is a risk factor for LMM-associated postural instability in the elderly. Consequently, with respect to the gastrocnemius muscles proprioception in LMM, it is necessary to perform assessments using muscle spindle stimuli.  相似文献   
48.
We recently presented a short communication on the preparation of epoxy‐based monoliths possessing highly ordered structures by polymerization induced phase separation based on the spinodal decomposition. In this article, we describe in detail on reaction mechanisms and structural properties of the epoxy‐based monoliths with well‐controlled macropores in the micrometer range. We prepared epoxy‐based monoliths based on diglycidyl ether of bisphenol A, bis(4‐aminocyclohexyl)methane, and polyethylene glycol with a bicontinuous structure by in situ step‐growth polymerization. Different morphology of epoxy‐based monoliths could be obtained by changing formulation of monomers and porogenic solvents. Characterizations of their morphologies were performed using scanning electron microscopy, mercury intrusion porosimetry, small angle X‐ray scattering, and gas adsorption measurement (BET method). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3272–3281, 2008  相似文献   
49.
Diversity‐oriented synthesis (DOS), which describes the synthesis of structurally diverse collections of small molecules, was developed, in part, to address combinatorial chemistry's shortfalls. In this paper, we hope to give an indication of what can be achieved using the DOS approach to library generation. We describe some of the most successful strategies utilized in DOS, with special focus on our own area of interest; DOS from simple, pluripotent starting materials. © 2008 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 8: 129–142; 2008: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.20144  相似文献   
50.
Decavanadate, one of the aggregated species of vanadate, is a potent inhibitor of several enzymes, including skeletal muscle myosin. However, its putative binding sites in myosin are largely unknown. Titration of the intrinsic fluorescence of myosin, purified from rabbit skeletal muscle, have been carried out in 0.3 M KCl, 5 mM CaCl2 and 25 mM Tris-HCl (pH 7.0), with 0.1 mg/ml myosin. In the 0-200 M total vanadate concentration range, decavanadate produced approximately 25% quenching of the intrinsic fluorescence of myosin, with an apparent dissociation constant in the micromolar range. This effect was found to be specific of decavanadate, because titration with metavanadate up to 200 M did not produce a significant quenching of the intrinsic fluorescence of myosin. This quenching was accompanied by a parallel decrease of the accessibility of myosin tryptophans to the water-soluble collisional quencher KI, with an apparent dissociation constant also in the micromolar range. It is concluded that the binding of decavanadate to high-affinity sites in myosin produces local conformational change(s) near the tryptophans more accessible to water in the three-dimensional structure of this protein.  相似文献   
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