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121.
该回顾性研究旨在探究老年Colles骨折X线Frykman分型在治疗方案选择中的应用价值。2015年1月~2018年1月期间收治的120例老年Colles骨折患者纳入研究对象,完善X线检查并进行Frykman分型,比较不同Frykman分型的Colles骨折患者X线掌倾角、尺偏角、桡骨短缩等指标。依据Frykman分型将患者分为关节内、外型骨折,比较两种骨折类型患者治疗方式及X线指标的变化情况,并采用Lidstrom治疗效果分级评估不同分组患者不同治疗方式的治疗效果。结果显示,120例Colles骨折患者根据Frykman分型:Ⅰ型26例(21.67%)、Ⅱ型29例(24.17%)、Ⅲ型14例(11.67%)、Ⅳ型16例(13.33%)、Ⅴ型12例(10.00%)、Ⅵ型11例(9.17%)、Ⅶ型8例(6.67%)、Ⅷ型4例(3.33%)。120例患者中共有关节外型骨折患者55例,其中30例行保守治疗,25例接受手术治疗;关节内型骨折患者65例,其中29例行保守治疗,36例接受手术治疗。两组骨折类型患者治疗后手术治疗的掌倾角、尺偏角、桡骨短缩值均明显优于保守治疗的患者,比较差异均有统计学意义(P<0.05)。关节外型Colles骨折患者治疗总可接受率(72.73%)与关节内型治疗总接受率(75.38%)(χ2=0.11,P=0.74)相当;关节外型组手术治疗总可接受率(88.00%)高于保守治疗(73.33%)(χ2=1.83,P=0.18);关节内型组手术治疗总可接受率(91.67%)明显高于保守治疗(55.17%)(χ2=11.53,P=0.00)。本研究证实老年Colles骨折X线Frykman分型在治疗方案选择中具有应用价值,关节外型骨折患者手术和保守治疗效果相当,关节内型患者优先选择手术治疗。 相似文献
122.
《Journal of Fluids and Structures》2008,24(3):366-381
The spatio-temporal characteristics of the separated and reattaching turbulent flow over a two-dimensional square rib were studied experimentally. Synchronized measurements of wall-pressure fluctuations and velocity fluctuations were made using a microphone array and a split-fiber film, respectively. Profiles of time-averaged streamwise velocity and wall-pressure fluctuations showed that the shear layer separated from the leading edge of the rib sweeps past the rib and directly reattaches on the bottom wall (x/H=9.75) downstream of the rib. A thin region of reverse flow was formed above the rib. The shedding large-scale vortical structures (fH/U0=0.03) and the flapping separation bubble (fH/U0=0.0075) could be discerned in the wall-pressure spectra. A multi-resolution analysis based on the maximum overlap discrete wavelet transform (MODWT) was performed to extract the intermittent events associated with the shedding large-scale vortical structures and the flapping separation bubble. The convective dynamics of the large-scale vortical structures were analyzed in terms of the autocorrelation of the continuous wavelet-transformed wall pressure, cross-correlation of the wall-pressure fluctuations, and the cross-correlation between the wall pressure at the time-averaged reattachment point and the streamwise velocity field. The convection speeds of the large-scale vortical structures before and after the reattachment point were Uc=0.35U0 and 0.45U0, respectively. The flapping motion of the separation bubble was analyzed in terms of the conditionally averaged reverse-flow intermittency near the wall region. The instantaneous reattachment point in response to the flapping motion was obtained; these findings established that the reattachment zone was a 1.2H-long region centered at x/H=9.75. The reverse-flow intermittency in one period of the flapping motion demonstrated that the thin reverse flow above the rib is influenced by the flapping motion of the separation bubble behind the rib. 相似文献
123.
A simple, sensitive, and useful concentration method for lovastatin (Lvt) in urine has been developed based on the transient
moving chemical reaction boundary method (tMCRBM) in capillary electrophoresis. The MCRB is formed with acidic sample buffer
(Gly-HCl) and alkaline running buffer (Gly-NaOH). The following optimal conditions were determined for stacking and separation:
electrophoretic buffer of 100 mM Gly- NaOH (pH 11.52), sample buffer of 20 mM Gly-HCl (pH 4.93), fused-silica capillary of
76 cm × 75-μm i.d (67 cm from detector), sample injection at 14 mbar for 3 min. A 21- to 26-fold increase in peak height was
achieved for detection of Lvt in urine under the optimal conditions compared with normal capillary zone electrophoresis. By
combining the sample pretreatment procedure with the stacking method, the sensitivity of Lvt in urine was increased by 105-
to 130-fold. The limits of detection (LOD) and quantification (LOQ) for Lvt in urine were decreased to 8.8 ng/mL and 29.2 ng/mL,
respectively. The intra-day and inter-day precision values (expressed as RSD) were 2.23–3.61% and 4.03–5.05%, respectively.
The recoveries of the analyte at three concentration levels changed from 82.65 to 100.49%. 相似文献
124.
Li J Gao J Sah S Satyal U Zhang R Han W Yu Y 《Applied biochemistry and biotechnology》2011,164(8):1366-1375
Mouse CXCL14/BRAK is a monocyte-selective chemokine which is expressed in almost all normal tissues. A flood of reports on
its new functions of tumor suppression and fat metabolism modulation has left CXCL14 a potential therapeutic candidate for
these diseases. Therefore, a simple accessible method is on demand for large-scale production of recombinant mouse CXCL14
protein for in vivo animal studies. Here, we introduce an efficient method for large-scale production of recombinant mouse
CXCL14, by which an 18-mg protein is produced from 2-L Escherichia coli culture with good bioactivity and low level of endotoxin. 相似文献
125.
Equations with non-local dispersal have been widely used as models in biology. In this paper we focus on logistic models with non-local dispersal, for both single and two competing species. We show the global convergence of the unique positive steady state for the single equation and derive various properties of the positive steady state associated with the dispersal rate. We investigate the effects of dispersal rates and inter-specific competition coefficients in a shadow system for a two-species competition model and completely determine the global dynamics of the system. Our results illustrate that the effect of dispersal in spatially heterogeneous environments can be quite different from that in homogeneous environments. 相似文献
126.
Sanyin Qu Dr. Chuanjiang Qin Dr. Ashraful Islam Prof. Jianli Hua Dr. Han Chen Prof. He Tian Dr. Liyuan Han 《化学:亚洲杂志》2012,7(12):2895-2903
A series of metal‐free organic dyes that were bridged by a diketopyrrolopyrrole moiety and were composed of indoline and triphenylamine as donor groups and furan and benzene as conjugated spacer groups were designed and synthesized for use in dye‐sensitized solar cells (DSCs). The photophysical properties, electrochemical properties, and performance of the DSCs were related to the structure of their corresponding dyes. Their absorption spectra broadened upon the introduction of the indoline and heterocyclic furan moieties through fine‐tuning of their molecular configuration. The overall conversion efficiencies of DSCs that were based on these dyes ranged from 5.14–6.53 %. Among the four dyes that were tested, indoline‐based ID01 and ID02 showed higher efficiencies (6.35 % and 6.53 %) as a result of their improved light‐harvesting efficiency and larger electron driving force. The ID01 dye, which contained an indoline moiety as an electron donor and a furan group as a π‐conjugated linker, showed an excellent monochromatic incident‐photon‐to‐current‐conversion efficiency (IPCE) spectrum (350–650 nm) with a maximum value of 78 % in the high plateau region and an onset value close to 800 nm. Intensity‐modulated photovoltage spectroscopy (IMVS) and impedance spectroscopy (IS) revealed that dyes that contained benzene conjugation spacers suppressed the charge‐recombination rate more efficiently than dyes that contained furan spacers, thereby resulting in improved photovoltage. 相似文献
127.
Based on our previous work of in‐capillary denaturing polymer electrophoresis, we present a study of RNA molecular separation up to 6.0 kilo nucleotide by pulsed field CE. This is the first systematic investigation of electrophoresis of a larger molecular mass RNA in linear hydroxyethylcellulose (HEC) under pulsed field conditions. The parameters that may influence the separation performance, e.g. gel polymer concentration, modulation depth and pulse frequency, are analyzed in terms of resolution and mobility. For denaturing and separating RNA in the capillary simultaneously, 2 M acetic acid was added into the HEC polymer to serve as separation buffer. Result shows that (i) in pulsed field conditions, RNA separation can be achieved in a wide range of concentration of HEC polymer, and RNA fragments between 0.3 and 0.6 kilo nucleotide are sensitive to the polymer concentration; (ii) under certain pulsed field conditions, RNA fragments move linearly as the modulation depth increases; (iii) 12.5 Hz is the resonance frequency for RNA reorientation time and applied frequency. 相似文献
128.
An interactive satisficing method based on alternative tolerance is proposed for fuzzy multiple objective optimization. The new tolerances of the dissatisficing objectives are generated using an auxiliary programming problem. According to the alternative tolerant limits, either the membership functions are changed, or the objective constraints are added. The lexicographic two-phase programming is implemented to find the final solution. The results of the dissatisficing objectives are iteratively improved. The presented method not only acquires the efficient or weak efficient solution of all the objectives, but also satisfies the progressive preference of decision maker. Numerical examples show its power. 相似文献
129.
The chaotic synchronization of Hindmarsh–Rose neural networks linked by a nonlinear coupling function is discussed. The HR neural networks with nearest-neighbor diffusive coupling form are treated as numerical examples. By the construction of a special nonlinear-coupled term, the chaotic system is coupled symmetrically. For three and four neurons network, a certain region of coupling strength corresponding to full synchronization is given, and the effect of network structure and noise position are analyzed. For five and more neurons network, the full synchronization is very difficult to realize. All the results have been proved by the calculation of the maximum conditional Lyapunov exponent. 相似文献
130.
In this paper, necessary and sufficient conditions for equality in the inequalities of Oppenheim and Schur for positive semidefinite
matrices are investigated.
Supported by National Natural Science Foundation of China (No. 10531070), National Basic Research Program of China 973 Program
(No. 2006CB805900), National Research Program of China 863 Program (No. 2006AA11Z209) and the Natural Science Foundation of
Shanghai (Grant No. 06ZR14049). 相似文献