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201.
传统的立体匹配方法建立在Lambertian的漫反射模型之上,漫反射模型的立体匹配在一个图像的大多部分是有效的,但是在处理图像中包含镜面反射的部分时结果会产生严重的匹配错误。笔者利用漫反射和镜面反射在灰度和最大色度上的不同,分离出镜面反射的像素,然后采用一种针对镜面反射的匹配测度,在图像中漫反射部分和镜面反射部分都能匹配得到正确的视差。结果证明了方法的有效性。  相似文献   
202.
连载一洋兰     
在中国兰花的栽培有悠久的历史,中国在《易经》中已有“同心之言,其臭如兰”的说法。孔子在过隐谷时,见幽兰独茂,叹曰:“夫兰当为王者香,今乃与众草为伍;譬贤者不逢时?鄙夫为伦也。”以兰花的幽香来比喻人之高雅。  相似文献   
203.
连载一洋兰     
在中国,兰花的栽培有悠久的历史,中国在《易经》中已有“同心之言,其臭如兰”的说法。孔子在过隐谷时,见幽兰独茂,叹曰:“夫兰当为王者香,今乃与众草为伍;譬贤者不逢时?鄙夫为伦也。”以兰花的幽香来比喻人之高雅。  相似文献   
204.
ATM is the most significant molecule involved in monitoring the genomic integrity of the cell. Any damage done to DNA relentlessly challenges the cellular machinery involved in recognition, processing and repair of these insults. ATM kinase is activated early to detect and signal lesions in DNA, arrest the cell cycle, establish DNA repair signaling and faithfully restore the damaged chromatin. ATM activation plays an important role as a barrier to tumorigenesis, metabolic syndrome and neurodegeneration. Therefore, studies of ATM-dependent DNA damage signaling pathways hold promise for treatment of a variety of debilitating diseases through the development of new therapeutics capable of modulating cellular responses to stress. In this review, we have tried to untangle the complex web of ATM signaling pathways with the purpose of pinpointing multiple roles of ATM underlying the complex phenotypes observed in AT patients.  相似文献   
205.
柿产业存在的问题及发展对策   总被引:1,自引:0,他引:1  
柿树是我国主栽果树种类之一,栽培历史悠久.从柿子品种资源丰富,栽培管理容易,市场需求大和产品品种多样等方面分析了我国发展柿产业的优势.通过对我国柿树生产、保鲜加工技术和营销方面所存在问题的研究,提出发展柿产业相应的对策:1)调整品种结构,培育和引进优良品种,普及栽培技术;2)加强柿贮藏保鲜和加工技术的研究;3)合理布局,发挥地域优势,发展特色产业链;4)建立服务体系,完善营销渠道.  相似文献   
206.
Accumulation of misfolded/unfolded aggregated proteins in the brain is a hallmark of many neurodegenerative diseases affecting humans and animals. Dysregulation of calcium (Ca2+) and disruption of fast axonal transport (FAT) are early pathological events that lead to loss of synaptic integrity and axonal degeneration in early stages of neurodegenerative diseases. Dysregulated Ca2+ in the brain is triggered by accumulation of misfolded/unfolded aggregated proteins in the endoplasmic reticulum (ER), a major Ca2+ storing organelle, ultimately leading to neuronal dysfunction and apoptosis. Calcineurin (CaN), a Ca2+/calmodulin-dependent serine/threonine phosphatase, has been implicated in T cells activation through the induction of nuclear factor of activated T cells (NFAT). In addition to the involvement of several other signaling cascades, CaN has been shown to play a role in early synaptic dysfunction and neuronal death. Therefore, inhibiting hyperactivated CaN in early stages of disease might be a promising therapeutic strategy for treating patients with protein misfolding diseases. In this review, we briefly summarize the structure of CaN, inhibition mechanisms by which immunosuppressants inhibit CaN, role of CaN in maintaining neuronal and synaptic integrity and homeostasis and the role played by CaN in protein unfolding/misfolding neurodegenerative diseases.  相似文献   
207.
The biological basis for regional and inter-species differences in cerebral cortical morphology is poorly understood. We focused on consanguineous Turkish families with a single affected member with complex bilateral occipital cortical gyration abnormalities. By using whole-exome sequencing, we initially identified a homozygous 2-bp deletion in LAMC3, the laminin γ3 gene, leading to an immediate premature termination codon. In two other affected individuals with nearly identical phenotypes, we identified a homozygous nonsense mutation and a compound heterozygous mutation. In human but not mouse fetal brain, LAMC3 is enriched in postmitotic cortical plate neurons, localizing primarily to the somatodendritic compartment. LAMC3 expression peaks between late gestation and late infancy, paralleling the expression of molecules that are important in dendritogenesis and synapse formation. The discovery of the molecular basis of this unusual occipital malformation furthers our understanding of the complex biology underlying the formation of cortical gyrations.  相似文献   
208.
Prostate cancer is the most common cancer affecting males in developed countries. It shows consistent evidence of familial aggregation, but the causes of this aggregation are mostly unknown. To identify common alleles associated with prostate cancer risk, we conducted a genome-wide association study (GWAS) using blood DNA samples from 1,854 individuals with clinically detected prostate cancer diagnosed at 相似文献   
209.
Most corporations are required by law to produce annual reports on their financial positions. These financial reports are accompanied by an auditor's report, which is an independent auditor's opinion on the fairness of the financial statements. To formulate their reports, auditors use a “personal-judgement” approach that heavily depends on their experience and expertise. This approach may be (1) ineffective and may lead to (2) different decisions, (3) personal bias, and (4) misleading judgements. These four drawbacks of a human auditor are a source of doubt and hesitation for every corporation. Therefore, the challenging question is: Can a computer do a better job? This paper focuses on the construction and implementation of a knowledge-based system, called the “Auditor's Report EXpert” (AREX), that is capable of formulating the opinion on financial statements, as expressed in the auditor's report. The knowledge used by AREX is acquired from the literature, and from a slate of practicing and academic auditors by means of questionnaires and in-depth interviews. A preliminary validation of AREX indicates that AREX is successful in performing the auditor's report task. Hence, we tentatively conclude that currently a computer program can support an auditor in his/her task. Moreover, in the foreseeable futur's reports that are effective, universal in their decisions, do not show a personal bias, and do not have misleading statements.  相似文献   
210.
Systemic Practice and Action Research - Action research studies in education often address learners’ needs and empower practitioners to effectively change instructional practices and school...  相似文献   
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