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151.
以再现手指握拳的动作姿态和运动轨迹为主要目标,探讨一种带关节仿生手指的优化设计,重点讨论了手指运动矩阵的建立,预期目标的采集,仿生手指的结构模拟,确定优化目标与约束函数,求数学模型的副近解等问题。  相似文献   
152.
Chronic diffuse interstitial fibrosis of the lung in uranium miners   总被引:1,自引:0,他引:1  
Many uranium miners have been disabled by and died of pulmonary fibrosis that was not recognized as an occupational disease. A review of animal studies, complications from whole body irradiation, pulmonary function, and mortality studies of uranium miners led us to suspect radiation-induced chronic diffuse interstitial fibrosis in miners who had inhaled excessive radon progeny. A selected group of uranium miners (22) with severe respiratory disease (but no rounded nodules in chest films) were studied. Lung tissue from five disclosed severe diffuse interstitial fibrosis, with "honeycomb lung" in all. Some also had small anthrasilicotic nodules and birefringent crystals. Although quartz crystals probably contributed, we concluded that the predominant injurious agent in these cases was alpha particles from radon progeny. This disease, after a long latent period, usually results in pulmonary hypertension, shortness of breath, and death by cardiopulmonary failure.  相似文献   
153.
Idiopathic pulmonary fibrosis (IPF) is generally defined as a progressive, fibrosing inflammatory disease of the lung parenchyma of unknown cause. It is characterized by slowly increasing dyspnea, diffuse interstitial lung infiltrates, restrictive lung dysfunction, and impaired gas exchange. Ultimately, it is fatal in most patients, and treatment options remain unsatisfactory. The advent of high-resolution computed tomography of the chest and modifications in the histopathologic classification of interstitial pneumonias have reshaped the concept of IPF. Although initially thought to be a relatively specific clinicopathologic entity, it seems likely that IPF as previously defined is a heterogeneous disorder consisting of several clinicopathologic entities with differing histopathologic patterns, clinical course, response to therapy, and prognosis. The most common histologic pattern in cases previously defined as IPF is usual interstitial pneumonia, which is associated with a median survival of less than 3 years. For accurate prognosis and optimal management of patients, the clinician should attempt to be as precise as possible in distinguishing various clinicopathologic entities that have been included under the clinical heading of IPF. In the future, we recommend that the use of the term "idiopathic pulmonary fibrosis" be restricted to patients with usual interstitial pneumonia and that clinicians recognize the fact that other idiopathic interstitial pneumonias do not have the same prognostic effect traditionally ascribed to IPF.  相似文献   
154.
刍议计算机反病毒技术的产生、发展和现状   总被引:1,自引:0,他引:1  
随着计算机病毒越来越猖撅,计算机安全越来越受到人们的重视,计算机反病毒技术也发展得越来越快。论文介绍了计算机反病毒的产生,介绍了当今最新最先进的计算机反病毒技术,有CPU反病毒技术、病毒码扫描技术、实时反病毒技术和虚拟机技术等。  相似文献   
155.
Electron Energy Loss Spectroscopy has been employed for investigation of the electronic states of amorphous and crystalline Fe73.6Cu1Nb2.4Si15.8B7.2 (FINEMET) alloy surface and alloy components. Electron energy losses have been measured for primary electron beam energies E0 from 150 to 650 eV. The characteristic energy loss spectra were composed of main peaks which we have interpreted due to surface and bulk plasmons, a combination of surface and bulk losses, high harmonics of plasma losses, inter-band transitions and ionization of core levels. The measured energies for the plasmon excitations were found not to agree with calculated values according to the classical theory for the collective oscillations in solids. Changes in the intensity lines of the surface and bulk plasmons were observed for all specimens depending on primary electron energy E0. The present results are compared with characteristic energy loss data reported in the literature.  相似文献   
156.
基于EoC的下一代广电网络多模式应用   总被引:1,自引:0,他引:1  
介绍如何在EoC上加上物联网网关,实现水、电、气抄表,家庭电气设备控制及通信,介绍IPQAM及IPTV双模式实现方法。  相似文献   
157.
The reaction of 4-aminotoluene with ozone in acetic acid was studied. It was found that the reaction proceeds at a high rate, giving predominantly tars. The product composition changes after acylation of the amino group: aliphatic peroxides prevailed among the oxidation products and 4-acetylaminobenzoic acid was identified (16%) as well. It was shown that the presence of a catalyst (cobalt(II) acetate) had no substantial effect on the oxidation selectivity for the methyl group (32%) and only the addition of potassium bromide increased the activity of the catalyst; the yield of 4-acetylaminobenzoic acid reached 70%. The mechanism of oxidation in the presence of a cobalt-bromide catalyst explaining the obtained results was discussed.  相似文献   
158.
159.
Libraries of random phage-displayed pentadeca- and hexapeptides were screened with the use of four monoclonal antibodies against the human plasma membrane Ca2(+)-ATPase. Bacteriophages specifically binding the antibodies were selected, and the amino acid sequences of the expressed peptides (mimotopes) were determined. Mimotopes for three antibodies (8B8, 2D8, F9) did not correspond to the Ca2(+)-ATPase sequence. Pentadecapeptides for the 7C8 antibodies displayed similarity to the fragment Glu1097-Arg1113 of the Ca2(+)-ATPase calmodulin-binding site. However, these antibodies failed to bind recombinant fragment Leu1069-Leu1220; therefore, the structure of this epitope remains obscure. This work opens a series of studies of the plasma membrane Ca2(+)-ATPase structure by means of monoclonal antibodies and the phage display method.  相似文献   
160.
High titers of antibodies to peptidoglycan of staphylococcus aureus were found in children with purulent-inflammatory diseases of staphylococcal etiology. This may be used for the diagnosis of staphylococcal infection.  相似文献   
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