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61.
Lower urinary tract dysfunctions (LUTD) restrict quality of life, resulting in decreased work productivity and emotional well‐being. However, most people are not diagnosed because they do not seek medical treatment. In addition, some facilities do not adequately train health professionals in the evaluation, diagnosis and treatment of these conditions. The study's objective was to develop a decision support system modelled on fuzzy logic that defines LUTD using the terminology of the International Continence Society. This methodological study aimed to develop a model that uses the maximum–minimum composition (max–min) of fuzzy relations that can perform differential diagnoses of LUTD. The model was tested in 100 cases (50 men and 50 women), and the data were obtained from medical records containing the clinical data and results of urodynamic studies. All medical records were reviewed by a specialist in urology. The model was capable of determining a diagnosis in full (62%) or partial (36%) agreement with the medical report. Agreement between the model and the medical report was excellent (kappa = 0·98, p ? 0·001, CI = 0·88–1) or substantial (kappa = 0·53, p ? 0·001, CI = 0·45–0·60), considering overestimative accordance (where accordance is assumed when at least one diagnosis is equal) and underestimative accordance (where accordance is assumed when all diagnoses are equal), respectively. The proposed model based on the max–min composition of fuzzy relationships is very simple and performed well. However, more tests are recommended before the model is used as a decision support system.  相似文献   
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Central to the normal function of the immune system is its ability to distinguish between self and non-self since failure to do so could provoke the onset of autoimmune disease. To avoid this possibility, the immune system employs several processes that include, negative selection, peripheral tolerance, and limiting DC antigen priming of na?ve T cells to the lymph nodes. Na?ve T cells must receive two independent signals from these antigen-presenting cells (APC) that other cells cannot provide if they are to become productively activated. The first is antigen-specific and occurs when T cell antigen receptors encounter the appropriate antigen-MHC complex on the APC--Signal 1. A second, antigen-independent signal is delivered through a T cell costimulatory molecule that engages its APC-expressed ligands--Signal 2. In the absence of a costimulatory signal T cells typically enter a state of anergy. Furthermore, the extent to which T cell activation occurs can be held in check through specific inhibitory receptors expressed on T cells. Understanding the basic mechanisms of how T cell activation is regulated has led to the development of therapeutic approaches for targeting T cell costimulatory and inhibitory pathways for turning on, or preventing the turning off immune responses in subjects with cancer. In this review we will discuss several T cell costimulatory and inhibitory pathways known to influence the development of anti-tumor immunity and how experimental manipulation of these signaling pathways has led to the generation of protective, or curative anti-tumor immunity in mice and humans.  相似文献   
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This study prospectively determined the feasibility and accuracy of prehospital thrombolytic therapy candidate selection by base station emergency physicians. During a 6-month period, paramedics acquired and transmitted prehospital 12-lead electrocardiograms (ECGs) and then applied a thrombolytic therapy contraindication checklist. Emergency physicians interpreted prehospital ECGs and prospectively selected candidates for thrombolytic therapy. A safety committee of cardiologists reviewed prehospital ECGs, checklists and hospital records to determine accuracy independently. Six hundred-eighty stable adult prehospital patients with a chief complaint of nontraumatic chest pain were initially evaluated. Two hundred forty-one patients were excluded because of (1) unsuccessful electrocardiographic transmission (149), (2) transport to nonparticipating facilities (72), and (3) unavailable medical records (20). No prehospital thrombolytic therapy was administered in this study. Of 439 cases, 91 (21%) had the final diagnosis of acute myocardial infarction, 38 (8.7%) had diagnostic prehospital ECGs, and 12 (2.7%) were selected by emergency physicians as candidates for thrombolytic therapy. Seventy percent of patients with myocardial infarction had checklist exclusions for thrombolytic therapy. Prehospital evaluation increased mean scene time (paramedic arrival on scene to scene departure) by 4 minutes. The median time from chest pain onset to paramedic arrival in patients with myocardial infarction was 60 minutes. The estimated average time saved if prehospital thrombolytic therapy had been available was 101 +/- 81 minutes. The safety committee concluded that acceptable accuracy of emergency physician prehospital electrocardiographic interpretation, checklist and case selection was achieved. It is concluded that emergency physicians can accurately identify candidates for prehospital thrombolytic therapy.  相似文献   
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尖叶清风藤化学成分的研究   总被引:6,自引:0,他引:6  
从尖叶清风藤(Sabia swinhoei Hmsl.exForb.etHemsl.)的地上部分分离出8个化合物,经理化常数测定和光谱解析,证明其中2个为新成分,分别命名为清风藤内酯(I)和清风藤酮(II),另外6个为已知化合物,即没药烯(III)、三十烷醇(IV)、β-谷甾醇(V)、二十八烷酸(VI)、齐墩果酸(VII)和胡萝卜甙(VIII)。  相似文献   
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南蛇藤素抑制豚鼠体外精子的受精能力   总被引:9,自引:0,他引:9  
南蛇藤素(Cel)对豚鼠精子前向运动(FM)、获能(Cap)、顶体反应(AR)和穿透去透明带仓鼠卵(SPA)均有明显的抑制作用,其作用强度随剂量而增加;对Cel的敏感性依次为精子Cap>FM>SPA>AR。Cel对豚鼠精子AR,FM和Cap的抑制作用比乙酸棉酚(GA)明显为强。  相似文献   
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