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71.
中医美容多媒体查询系统的数据库设计   总被引:1,自引:0,他引:1       下载免费PDF全文
将中医美容知识的查询系统与多媒体技术结合,使用FoxProforWindows完成查询系统的主要设计思想。设计思想包括数据库设计、查询设计、图像处理和菜单设计4个方面。  相似文献   
72.
Cross relaxation between macromolecular protons and water protons is known to be important in biologic tissue. In magnetic resonance (MR) imaging sequences, selective saturation of the characteristically short T2 macromolecular proton pool can produce contrast called magnetization transfer contrast, based on the cross-relaxation process. Selective saturation can be achieved with continuous wave irradiation several kilohertz off resonance or short, intense 0° pulses on resonance. The authors analyze 0° binomial pulses for T2 selective saturation, present design guidelines, and demonstrate the use of these pulses in spin-echo imaging sequences in healthy volunteers and patients. Using the phenomenologic Bloch equations modified for two-site exchange, the authors derive the analytic expressions for water proton relaxation under periodic pulsed saturation of the macromolecular protons. This relaxation is shown to be monoexpo-nential, with a rate constant dependent on the saturation pulse repetition rate and the individual and cross-relaxation rates.  相似文献   
73.
[目的] 介绍方剑乔教授针药结合治疗类风湿性关节炎的临床思辨特色及其临证经验。[方法] 通过整理、回顾、分析方教授治疗类风湿性关节炎的相关文献及医案,从中医病因病机和治则治法等方面,总结归纳方教授治疗类风湿性关节炎的学术经验,并列举医案一则予以佐证。[结果] 临床思辨上,方教授认为“痰、瘀、虚交错”为该病的基本病机,治疗宜针药结合,主要起到同效相须、异效互补和反效制约的作用。临证治疗上,方教授强调,针刺宜整体治疗与局部穴位兼顾,须重视经络辨证。合理应用电针,疼痛急性发作期电针频率多选择“先高后低”,先100 Hz/10~15 min,后2 Hz/30 min;慢性疼痛期电针治疗多选择疏密波(2/100 Hz)。用药强调精准辨证,在该病四种基本证型的基础上提出了阴虚湿热兼证的概念,确立了滋阴清热、通络止痛的治疗大法。倡导适时采用经皮穴位电刺激治疗,其操作简单,携带方便,在镇痛方面具有明显的优势。所举病案采用西药甲氨蝶呤片抑制免疫,稳定病情;中药以祛风除湿为主,佐以藤类药通络行窜、祛风止痛;电针治疗选择频率为2/100 Hz的疏密波调和气血、通络止痛。经治疗后,患者症状缓解,相关指标趋于正常。[结论] 方剑乔教授根据本病的病因病机及临床特点进行辨证论治,针药并重,中西医取长补短,临床特色鲜明,治疗效果显著,值得临床借鉴和推广。  相似文献   
74.
The cells in the primary visual cortex possess numerous functional properties that are more complex and varied than those seen in the cortical input. These properties result from the network of intrinsic cortical connections running across the cortical layers and between cortical columns. In the current study we relate the long receptive fields that are characteristic of layer 6 cells to the input that these cells receive from layer 5. The axons of layer 5 pyramidal cells project over long distances within layer 6, enabling layer 6 cells to collect input from regions of cortex representing large parts of the visual field. When layer 5 was locally inactivated by injection of the inhibitory transmitter GABA, layer 6 cells lost sensitivity over the portion of their receptive fields corresponding to the inactivated region of layer 5. This suggests that the extensive convergence in the projection from layer 5 to layer 6 is responsible for generating the long receptive fields characteristic of the layer 6 cells.  相似文献   
75.
The effects of clonidine and yohimbine on human information processing   总被引:1,自引:1,他引:0  
The effects of clonidine and yohimbine on human information processing were tested in six normal volunteers ages 18–30 years. Subjects were tested in a pre-post design with sessions conducted at weekly intervals. Three drug conditions were: Placebo (lactose), 0.2 mg clonidine, and 30 mg yohimbine. Two choice reaction time (RT) tasks were used. One was a stimulus evaluation-response selection task (SERS) that has been shown to be sensitive tod-amphetamine, methylphenidate and scopolamine. The other task was to assess stimulus pre-processing and used spatial frequency as a discriminative stimulus. The principle finding was that clonidine slowed RT; this effect was significant for both tasks. In contrast, yohimbine tended to speed RT, but the effects were significant only for the spatial frequency task on some analyses while not for others. RTs to high spatial frequency stimuli were speeded more than for low spatial frequency. The effects of these two NE drugs were compared with findings withd-amphetamine and scopolamine and interpreted within the framework of a serial information processing model proposed by Callaway (1983). Specifically, it is suggested that yohimbine and clonidine affect an early pre-processing stage.  相似文献   
76.
基于Client/Server结构的医院图像处理系统   总被引:1,自引:0,他引:1  
作者介绍了一种医院图像处理系统,可将医院的各种设备所产生的医疗图象资料,动用先进的可读写光盘为存储介质有效地进行存储,再通过通信网络及时地传送到医院的各个部门,辅助医生进行临床诊断及科研,提高有关科室及整个医院的工作效率及经济效益。  相似文献   
77.
Our studies are mainly focused on developing strategies of immune regulation. In the case of infectious and neoplastic disease, our approach is to upregulate cell-mediated immunity to viral of tumor antigens using an intracellular bacterium as a vector for targeting these antigens to the major histocompatibility complex (MHC) class I and class II pathways of antigen processing, in addition to exploiting the adjuvant properties of the vector to stimulate innate immunity. In the area of autoimmunity, we are attempting to downregulate the immune response by specific immune intervention directed against autoreactive T cells. In these studies we use murine models for multiple sclerosis. Our approach is to use both rationally designed T cell receptor (TCR) peptide analogs and recombinant viral vectors that express TCR components to regulate the disease.  相似文献   
78.
本文介绍一种具有较高性能价格比的生物医学电镜图像处理系统,该系统以IBM PC/XT,AT或386计算机为主机,图像接口板直接插入机内扩展槽。应用软件可对生物医学图像作图像处理和定量计算。作者通过对人膈腹膜超微结构进行定量分析,为腹水的治疗和腹膜透析(CAPD)等临床医学研究,提供了形态学定量资料。  相似文献   
79.
Our laboratory is interested in the properties of proteins that render them immunogenic, and how such immunogenicity may be modulated in vivo. We are attempting to enhance the immune response in the design of more effective vaccines against viral diseases, such as HIV, and against tumor antigens expressed on breast, ovarian, and cervical cancer and B cell lymphomas. Our main approach is to use a facultative intracellular bacterium, Listeria monocytogenes, which has the unusual ability to live and grow in the cytoplasm of the cell and is thus an excellent vector for targeting passenger antigens to the major histocompatibility complex (MHC) class I pathway of antigen processing with the generation of authentic cytotoxic T lymphocytes (CTL) epitopes. In the field of tumor immunotherapy, we are also developing nonliving vaccine vectors for tumor antigens.  相似文献   
80.
Word-specific cortical activity as revealed by the mismatch negativity   总被引:3,自引:0,他引:3  
Neurophysiological brain activity evoked by individual spoken words and pseudowords was recorded and the mismatch negativity (MMN), an automatic index of experience-dependent auditory memory traces, was calculated. Consistent with earlier reported results, the MMN response to word-final syllables was enhanced compared with that elicited by the same syllables placed in a pseudoword context. Here we now demonstrate that the enhancement of the MMN elicited by two individual words showed different scalp topographies. The early word-specific brain activity is consistent with the assumption that the memory traces activated by individual words are carried by large neuronal ensembles that differ in their distributions over the cortex. Current source estimates localized the between-word differences in the right hemisphere and in parieto-occipital left-hemispheric areas. The differential brain responses to individual words appeared as early as ∼100 ms after the recognition points of the words, suggesting that their specific memory traces become active almost immediately after the information in the acoustic input is sufficient for word identification.  相似文献   
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