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阴茎癌56例临床分析   总被引:6,自引:0,他引:6  
目的 :探讨阴茎癌有效合理的治疗方法。方法 :总结分析 5 6例阴茎癌发病及治疗情况 ,其中鳞状细胞癌5 0例 ,乳头状瘤癌变 6例 ,行阴茎部分切除术 48例 ,阴茎全切并会阴部造口术 6例 ,双腹股沟淋巴清扫术 10例 ,包皮环切并血卟啉光敏治疗 2例。结果 :5 1例获得随访。行阴茎部分切除术者 5年和 10年生存率分别为83 3 %和 80 % ,行阴茎全切术者 5年生存率为 6 6 8%。结论 :包茎及包皮过长是导致阴茎癌的主要诱因。对于Ⅰ、Ⅱ期阴茎癌行阴茎部分切除术疗效确切  相似文献   
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Several learning approaches have been used to predict RNA-binding amino acids in a protein sequence, but there has been little attempt to predict protein-binding nucleotides in an RNA sequence. One of the reasons is that the differences between nucleotides in their interaction propensity are much smaller than those between amino acids. Another reason is that RNA exhibits less diverse sequence patterns than protein. Therefore, predicting protein-binding RNA nucleotides is much harder than predicting RNA-binding amino acids. We developed a new method that removes data redundancy in a training set of sequences based on their features. The new method constructs a larger and more informative training set than the standard redundancy removal method based on sequence similarity, and the constructed dataset is guaranteed to be redundancy-free. We computed the interaction propensity (IP) of nucleotide triplets by applying a new definition of IP to an extensive dataset of protein-RNA complexes, and developed a support vector machine (SVM) model to predict protein binding sites in RNA sequences. In a 5-fold cross-validation with 812 RNA sequences, the SVM model predicted protein-binding nucleotides with an accuracy of 86.4%, an F-measure of 84.8%, and a Matthews correlation coefficient of 0.66. With an independent dataset of 56 RNA sequences that were not used in training, the resulting accuracy was 68.1% with an F-measure of 71.7% and a Matthews correlation coefficient of 0.35. To the best of our knowledge, this is the first attempt to predict protein-binding RNA nucleotides in a given RNA sequence from the sequence data alone. The SVM model and datasets are freely available for academics at http://bclab.inha.ac.kr/primer.  相似文献   
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The last ten years of efforts in developing automated insulin dosing systems have led to one hybrid closed-loop device in the US market with more in the late stages of development. Much of the focus has been on algorithms, including closed-loop, detection of sensor and pump faults, and safety. There has been less discussion in the open literature about user interface design and related options. This article provides perspectives on automated insulin delivery (AID) system design by analyzing commonly used devices, such as bicycles and car entertainment systems. The recent Boeing 737 Max 8 disasters are used to highlight related challenges with AID systems. The role that system engineers can play in the do it yourself artificial pancreas system movement is also discussed. The human-in-the-loop remains by far the most important “component” of any AID system.  相似文献   
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目的 探讨日本血吸虫病肝、脾B超指标间以及与感染次数、感染时间和每克粪便平均虫卵数 (EPG )的相关性。 方法 采用典型相关方法分析肝、脾B超指标间及其与感染次数、感染时间和EPG的相关性 ,用冗余度分析方法分析肝、脾变异中有多少比例互为相关。 结果 男、女无既往感染组和既往感染组的第 1典型相关系数分别为0.7842、0.5483和 0.5800、0. 4220 (P值均 <0.01) ;男、女粪检阴性组和阳性组的第 1典型相关系数分别为 0.6063、0.5215和 0.6595、0.3849(P值均 <0. 01) ;男、女无既往感染组肝B超指标变异分别有 43.5 %和 17.5 %与脾B超指标变异有关 ,而既往感染组分别为 22.1%和 11.4%。而在男、女粪检阴性组分别为 26.8%和 16.8% ,粪检阳性组分别为 2 7.6%和 10.7% ;既往感染组 ,感染次数、调查时距首次感染时间和粪检阳性者的EPG与肝、脾B超指标的典型变量均无相关性 (P >0.05 )。 结论 日本血吸虫病肝、脾B超指标间具有典型相关关系 ,且男性的相关性大于女性 ;在既往感染者中感染次数、调查时距首次感染时间和粪检阳性者EPG与肝、脾B超指标的典型变量间均未发现相关性。  相似文献   
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目的:研究早产儿视网膜病变新生血管形成过程中VEGF对TGF-β表达的影响。方法:体外培养人视网膜血管内皮细胞(HRCECs),分别转染重组腺相关VEGF病毒和VEGF的RNA干扰质粒到HRCECs,增高和抑制VEGF的表达,通过二氯化钴诱导HRCECs缺氧,观察TGF-β在不同VEGF水平下的mRNA表达变化,同时观察HRCECs增殖的变化。结果:高表达VEGF组(C组),低表达VEGF组(D组),阴性对照组(E组),阳性对照组(F组)的VEGF/actin分别为:1.15±0.77,0.36±0.31,0.28±0.16,0.83±0.72;而TGF-β/actin为:0.55±0.39,0.92±0.57,0.18±0.07,0.70±0.45,当VEGF高表达,TGF-β的mRNA表达下调;在VEGF低表达时,TGF-β的mRNA表达上调。结论:TGF-β能部分代偿VEGF的功能,视网膜新生血管形成过程中生长因子具有冗余性。  相似文献   
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Children discriminated tactual dot patterns by size or form and by texture. Adding irrelevant, easy, correlated texture cues improved size and form discrimination while orthogonal irrelevant texture cues interfered. Facilitation and interference could be reversed by reversing dimensional difficulty, but were found also when the two dimensions were equally accurate, for both blindfolded sighted and for blind children. The theoretical implication with regard to age effects, and practical implications for using dot numerosity and dot density differences for Braille learning were discussed.  相似文献   
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结合SITAR分布式入侵容忍体系结构和ITPAS密码认证体系统的特点,提出了一个具有入侵容忍功能的分布式密码认证系统模型,并在设计中考虑了冗余、多样性、代理、共享秘密和分布式入侵检测等技术,以求解决认证服务的入侵容忍问题和密码数据库的防字典攻击问题。  相似文献   
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The performance of a standing reaching task that necessitates some forward bending requires: (1) the coordination of multiple joints (i.e., the trunk and limb segments) to reach the target, and (2) the preservation of postural stability. It has been proposed that the neural control of multijoint reaching tasks can be simplified by time scaling of joint motions while keeping joint excursions the same. To determine if time scaling of joint motions was used in this more complex reaching task, we had 20 healthy subjects (10 male and 10 female) reach for two targets located in a parasagittal plane while standing on a force platform. Subjects reached for the targets at a comfortable speed and a fast paced speed. Sagittal plane motions of the right shank, thigh, pelvis, trunk, humerus, and forearm were measured. At the fast paced movement speeds subjects had significantly larger excursions of the thigh, pelvis, humerus, and forearm compared to the comfortable speed. Thus, segment motions are not simply time scaled for standing multijoint reaches. We explored three possible reasons for not obeying time scaling: (1) to reduce scaling of peak kinetic energy, (2) to reduce scaling of peak horizontal ground reaction force, and (3) a convergence of movement strategies at faster speeds. While subjects modified their movement strategy in relationship to movement speed, these changes had no significant effect on the expected scaling of peak kinetic energy, or peak horizontal ground reaction forces. Given the intersubject differences in movement strategies used to perform these reaching tasks at the fast speeds, a convergence of movement strategies was ruled out. We propose that the increase in segment motions with speed may be a consequence of rules underlying motor output, the increases being greater for segments in which viscoelastic resistance to movement is more significant compared to inertial resistance. Electronic Publication  相似文献   
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