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1.
正Osteoarthritis(OA)is a degenerative joint disease,typified by a loss of quality of cartilage and changes in bone at the interface of a joint,resulting in pain,stiffness,and reduced mobility."According to the World Health Organization,40%of people over the age of 70 have OA.This joint disease affects  相似文献   

2.
Objective: To investigate the role of 99mTc-TRODAT-1 SPECT in diagnosis and assessing severity of idiopathic Parkinson's disease (PD). Methods: Thirty-eight patients with primary, tentative diagnosis of PD and eighteen age-matched normal controls were studied with 99mTc-TRODAT-1 SPECT imaging. The regions of interests (ROIs) were drawn manually on cerebellum (CB), occipital cortex (OC) and three transverse plane slice-views of striatums, the semiquantitative BG (background)/[(OC CB)/2] were then calculated. Results: A lower uptake of 99mTc-TRODAT-Ⅰ in striatums were displayed in thirty-six out of thirty-eight PD patients by visual inspection, compared to controls. In twenty-four PD cases with HYS (Hoehn and Yahr scale) stage I, a greater loss of DAT uptake was found in striatum and its subregions contralateral striatum to the affected limbs than in the same regions of the controls, although the striatal uptake was bilaterally reduced. Using Spearman correlation analysis showed that the reduction of the uptake ratios significantly correlated with the UPDRS in striatum and all its subregions in the PD group (P<0.05), a similar change was also found in the putamen by using the rating scale of Hoehn and Yahr (P<0.05).However, analysis of variance (ANOVA) did not show any relationship between the decreasing uptake of 99mTc-TRODAT-1 and increasing severity of PD patients, although the specific uptake of 99mTc-TRODAT-Ⅰ was continuously decreased in the striatum by visual inspection with the progress of PD from HYS stage Ⅰ to Ⅲ. Conclusion: 99mTc-TRODAT- 1 SPECT imaging may serve as a useful method for improving the correct diagnosis of PD. In assessing the role of99mTc-TRODAT- 1 SPECT in disease severity of PD, UPDRS can offer a comprehensive index, although the Hoehn and Yahr assessment may be available in part.  相似文献   

3.
Several models of experimental ulcerative colitis have been reported previously. However, none of these models showed the optimum characteristics. Although dextran sulfate sodium-induced colitis results in inflammation resembling ulcera-tive colitis, an obvious obstacle is that dextran sulfate sodium is very expensive. The aim of this study was to develop an inex-pensive model of colitis in rats. Sprague-Dawley rats were treated with 2% dextran sulfate sodium in drinking water for 3 d fol-lowed by an intracolonic administration of 30% ethanol. The administration of 2% dextran sulfate sodium followed by 30% ethanol induced significant weight loss, diarrhea and hematochezia in rats. Severe ulceration and inflammation of the distal part of rat colon were developed rapidly. Histological examination showed increased infiltration of polymorphonuclear leukocytes, lymphocytes and existence of cryptic abscesses and dysplasia. The model induced by dextran sulfate sodium at lower concentra-tion followed by 30% ethanol is characterized by a clinical course, localization of the lesions and histopathological features similar to human ulcerative colitis and fulfills the criteria set out at the beginning of this study.  相似文献   

4.
Objective:To investigate the role of ~(99m)Tc-TRODAT-1 SPECT in diagnosis and assessing severity of idiopathicParkinson's disease(PD).Methods:Thirty-eight patients with primary,tentative diagnosis of PD and eighteen age-matchednormal controls were studied with ~(99m)Tc-TRODAT-1 SPECT imaging.The regions of interests(ROIs)were drawn manually oncerebellum(CB),occipital cortex(OC)and three transverse plane slice-views of striatums,the semiquantitative BG(back-ground)/[(OC CB)/2]were then calculated.Results:A lower uptake of ~(99m)Tc-TRODAT-1 in striatums were displayed inthirty-six out of thirty-eight PD patients by visual inspection,compared to controls.In twenty-four PD cases with HYS(Hoehn andYahr scale)stage Ⅰ,a greater loss of DAT uptake was found in striatum and its subregions contralateral striatum to the affectedlimbs than in the same regions of the controls,although the striatal uptake was bilaterally reduced.Using Spearman correlationanalysis showed that the reduction of the uptake ratios signifi  相似文献   

5.
A new method to detect multiple outliers in multivariate data is proposed. It is a combination of minimum subsets, resampling and self-organizing map (SOM) algorithm introduced by Kohonen,which provides a robust way with neural network. In this method, the number and organization of the neurons are selected by the characteristics of the spectra, e. g., the spectra data are often changed linearly with the concentration of the components and are often measured repeatedly, etc. So the spatial distribution of the neurons can be arranged by this characteristic. With this method, all the outliers in the spectra can be detected, which cannot be solved by the traditional method, and the speed of computation is higher than that of the traditional neural network method. The results of the simulation and the experiment show that this method is simple, effective, intuitionistic and all the outliers in the spectra can be detected in a short time. It is useful when associated with the regression model in the near infra-red research.  相似文献   

6.
Asymmetric stereoscopic video coding can take advantage of binocular suppression in human vision by representing one of the two views in lower quality.This paper proposes a bit allocation strategy for asymmetric stereoscopic video coding.In order to improve the accuracy of bit allocation and rate control in the left view,a proportionalintegral-derivative controller is adopted.Meanwhile,to control the quality fluctuation between consecutive frames of the left view,a quality controller is adopted.Besides,a fuzzy controller is proposed to control the variation in quality between the left and right views by comparing the PSNR disparity of two views with a fixed threshold,which is used to quantize the binocular psycho-visual redundancy and adjust the quantization parameter (QP) of the right view correspondingly.The proposed algorithm has been implemented in H.264/AVC video codec,and the experimental results show its effectiveness in rate control while keeping a good quality for the left view,and fewer bits are allocated for the right view so that the overall bit rate is saved by 7.2% at most without the loss of subjective visual quality for stereoscopic video.  相似文献   

7.
In this paper,a geometric approach to fault detection and isolation (FDI) is applied to a Multiple-Input Multi-ple-Output (MIMO) model of a frame and the FDI results are compared to the ones obtained in the Single-Input Single-Output (SISO),Multiple-Input Single-Output (MISO),and Single-Input Multiple-Output (SIMO) cases. A proper distance function based on parameters obtained from parametric system identification method is used in the geometric approach. ARX (Auto Regressive with eXogenous input) and VARX (Vector ARX) models with 12 parameters are used in all of the above-mentioned models. The obtained results reveal that by increasing the number of inputs,the classification errors reduce,even in the case of applying only one of the inputs in the computations. Furthermore,increasing the number of measured outputs in the FDI scheme results in decreasing classification errors. Also,it is shown that by using probabilistic space in the distance function,fault diagnosis scheme has better performance in comparison with the deterministic one.  相似文献   

8.
周静  蒋秀丽 《海外英语》2013,(2X):146-147
Translation always plays the crucial role in the cross-culture communication and the development of human being’s history of civilization. The author of this papertries to make an analysis and contrast of the two translation models: the Jerome model and the Horace model, pointing out that it is because of different circumstances that different translation models are used in the translation.  相似文献   

9.
Alpha-synuclein plays an important role in Parkinson's disease (PD). The current study of alpha-synuclein mainly concentrates at the gene level. However, it is found that the study at the protein level has special significance. Meanwhile, there is free information on the Internet, such as databases and algorithms of protein-protein interactions (PPIs). In this paper, a novel method which integrates distributed heterogeneous data sources and algorithms to predict PPIs for alpha- synuclein in silico is proposed. The PPIs generated by the method take advantage of various experimental data, and indicate new information about PPIs for alpha-synuclein. In the end of this paper, the result illustrates that the method is practical. It is hoped that the prediction result obtained by this method can provide guidance for biological experiments of PPIs for alpha-synuclein to reveal possible mechanisms of PD.  相似文献   

10.
Idiopathic pulmonary arterial hypertension(IPAH) is a rare disease of unknown etiology.The exact pathogenesis of pulmonary arterial hypertension is still not well known.In the past decades,many protein molecules have been found to be in-volved in the development of IPAH.With proteomic techniques,profiling of human plasma proteome becomes more feasible in searching for disease-related markers.In present study,we showed the protein expression profiles of the serum of IPAH and healthy controls after depleting a few high-abundant proteins in serum.Thirteen spots had changed significantly in IPAH com-pared with healthy controls and were identified by LC-MS/MS.Alpha-1-antitrypsin and vitronectin were down-regulated in IPAH and may be valuable candidates for further explorations of their roles in the development of IPAH.  相似文献   

11.
12.
LUO Si-yu 《海外英语》2013,(23):226-227
Invisibility is crucial to construct identity in Ralph Ellison’s novel Invisible Man.Being invisible like a formless phantom and having only the voice echoing is a way of pushing the human existence to its ultimate state.Without the distraction of the body,the human identity could stand out like a candle in the darkness.The process of breaking out of the body is significant to the modern man,because modernity causes a sense of identity loss in them.  相似文献   

13.
钱钧 《海外英语》2013,(6X):275-278
This paper introduces Kim’s integrative theory of communication and cross-cultural adaptation. Building on a broad range of existing concepts, models, and research data across disciplines, Kim’s theory addresses two central questions: (a) What is the essential nature of the adaptation process? and (b) why are some strangers more successful than others in the adaptation process? The first question is addressed in the form of a process model. The second question is addressed in the form of a structural model. It is by far the most broad-based theoretical account of cross-cultural adaptation.  相似文献   

14.
DNA is the hereditary material in humans and almost all other organisms. It is essential for maintaining accurate transmission of genetic information. In the life cycle, DNA replication, cell division, or genome damage, including that caused by endogenous and exogenous agents, may cause DNA aberrations. Of all forms of DNA damage, DNA double-strand breaks(DSBs) are the most serious. If the repair function is defective, DNA damage may cause gene mutation, genome instability, and cell chromosome loss, which in turn can even lead to tumorigenesis. DNA damage can be repaired through multiple mechanisms. Homologous recombination(HR) and non-homologous end joining(NHEJ) are the two main repair mechanisms for DNA DSBs. Increasing amounts of evidence reveal that protein modifications play an essential role in DNA damage repair.Protein deubiquitination is a vital post-translational modification which removes ubiquitin molecules or polyubiquitinated chains from substrates in order to reverse the ubiquitination reaction. This review discusses the role of deubiquitinating enzymes(DUBs) in repairing DNA DSBs. Exploring the molecular mechanisms of DUB regulation in DSB repair will provide new insights to combat human diseases and develop novel therapeutic approaches.  相似文献   

15.
INTRODUCTION Along with the coming of the aged society, the morbidity of Parkinson抯 disease is also raised. But there is lack of objective experimental diagnostic indexes for it during the early stage. Magnetic resonance spectroscopy (MRS) is a noninvasive technique for measuring the chemical compounds in the human body. 1H MRS can be used to analyze many metabolites, such as N-acetyaspartate (NAA), Creatine (Cr), Choline (Cho) and so on. In Parkin-son抯 disease, the concentratio…  相似文献   

16.
This paper provides an overview of models and methods for estimation of lifetime of technical components. Although the focus in this paper is on wind turbine applications, the major content of the paper is of general nature. Thus, most of the paper content is also valid for lifetime models applied to other technical systems. The models presented and discussed in this paper are classified in different types of model classes. The main classification used in this paper divides the models in the following classes: physical models, stochastic models, data-driven models and artificial intelligence, and combined models. The paper provides an overview of different models for the different classes. Furthermore, advantages and disadvantages of the models are discussed, and the estimation of model parameters is briefly described. Finally, a number of literature examples are given in this paper, providing an overview of applications of different models on wind turbines.  相似文献   

17.
A new study shows that large amounts of vitamins and minerals can slow the loss of sight linked to aging. The condition is called age related macular degeneration (衰退) or A-M-D. The disease is a major cause of blindness among old people. Doctors do not know what causes it. The disease destroys the central part of the retina(视网膜), the cells at the back of the eye that gather light. The first sign of A-M-D usually is a loss of visual clearness. People with the disease have trouble reading, driving and recognizing faces. They cannot see clearly through the center of their eyes. They must  相似文献   

18.
No failure, moderate failure, severe failure, and slight failure are the four failure modes generalized observed in the dynamic response of the single-layer reticulated dome under vertical impact load on apex. TE (the time that the end of impact force) and TF (the time that members are broken) are two key times in the failure process. Characteristics of dynamic responses at the two key times are shown in order to make the failure mechanism clear. Then three steps of energy transfer are summarized, i.e. energy applying, energy loss and energy transfer, energy consump-tion. Based on the three steps, energy transfer process for the failure reticulated dome under once impact is introduced. Energy transmissibility and local loss ratio are put forward firstly to obtain EL F(the energy left in the main reticulated dome) from the initial kinetic energy of impactor. More-over, the distribution of failure modes is decided by EL F which leads to the maximum dynamic re-sponse of the reticulated dome, but not by the initial impact kinetic energy of impactor.  相似文献   

19.
Background: An ideal aneurysm model of cerebral aneurysm is of great importance for studying the pathogenesis of the lesion and testing new techniques for diagnosis and treatment. Several models have been created in rabbits and are now widely used in experimental studies; however, every model has certain intrinsic limitations. Here we report the development of a novel saccular aneurysm model in rabbits using an arterial pouch that is subject to in vitro pre-digestion with combined elastase and collagenase. Methods: A segment of right common carotid artery (CCA) was dissected out and treated with elastase (60 U/ml, 20 min) followed by type I collagenase (1 mg/ml, 15 min) in vitro. The graft was anastomosed to an arterial arch built with the left CCA and the remaining right CCA, while the other end of the graft was ligated. The dimension and tissue structure of the pouch were analysed immediately, 2 or 8 weeks after operation. Findings: Ten terminal aneurysms were produced. The gross mor-phology of the aneurysm resembles the human cerebral terminal aneurysms. We have observed the following pathological changes: (1) growth of the aneurysm (mean diameter increased from (2.0±0.1) to (3.2±0.3) mm at 2 weeks, P<0.001, n=7~10); (2) thinning of the aneurysmal wall (the mean wall thickness decreased to 44% at 2 weeks), which was accompanied by significant losses of elastic fibres, collagen and the cellular component; and (3) spontaneous rupture (3 out of 9, one aneurysm ruptured 24 h after operation with the other two at 2 and 4 weeks respectively). Conclusion: This rabbit arterial pouch model mimics human cerebral aneurysms in relation to morphology and histology. In particular, this model exhibited an increased tendency of spontaneous rupture.  相似文献   

20.
To consider the bending collapse of the pipes in the latticed frames, based on the multi-scale simulation, the collapsed parts of the pipe are meshed by the shell elements as micro-scaled models, and the other parts are meshed by beam elements macro-models. The incremental displacement constraint equations for the nodes on the section between the two models are established based on the plane section premise of classical beam theory. The method to introduce the constraint equations is derived based on the Updated Largrangian method. The location of the micro-model is predicted by the stress field of the beam element, and the length of the collapsed part is adjusted by the plastic energy in the micro model. Several examples are included to illustrate the efficiency and accuracy of this method.  相似文献   

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