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961.
目的:探讨单气囊小肠镜(single-balloonenteroscop,SBE)在胶囊内镜检查阴性的可疑小肠疾病患者中的应用价值。方法:选取在我院行胶囊内镜检查无异常发现,后行单气囊小肠镜检查的可疑小肠疾病患者24例,分析后者对胶囊内镜检查阴性可疑小肠疾病患者的阳性发现率和病因的分布特点。结果:24例行SBE检查者有22例(91.7%)获得成功,2例失败,10例被检出阳性病变,其中间质瘤5例,小肠息肉2例,过敏性紫癜1例,血管畸形2例,SBE对胶囊内镜检查阴性的患者小肠疾病的再检出率为41.7%。结论:胶囊内镜和SBE在小肠疾病的诊断上有着各自的优缺点,对于胶囊内镜检查阴性的可疑小肠疾病患者进一步行SBE检查有助于确诊。 相似文献
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目的:探讨术前访视应用ipad在术前访视中对手术患者心理状态的影响。方法:将300例择期手术患者随机分为对照组(150例)和实验组(150例),对照组采用常规术前访视方案;实验组在此基础上结合ipad展示围术期相关信息,采用焦虑自量表评估两组病人入院时和入手术室时的焦虑状况及血压、心率等指标,并且进行术后并发症和满意度的调查。结果:改良术前访视后焦虑评分、收缩压、舒张压、心率实验组明显低于对照组。结论:术前访视应用ipad可明显减轻手术病人术前的焦虑。 相似文献
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目的:分析介入治疗对于成人非创伤性股骨头缺血性坏死的疗效。方法:采用介入方法治疗95例共117髋非创伤性股骨头缺血性坏死。对比介入治疗前后DSA造影分型结果及血供异常例数。结果:117患髋中,Ia型的31病髋中,11髋(35.48%)介入治疗后动脉主干再通;Ib型的27髋中,24髋(88.89%)介入治疗后分支再通;II型的11髋中,5髋(45.45%)实质期股骨头缺损面积缩小;III型的10髋中,8髋(80.00%)静脉期见股骨头浓密染色明显减轻;Ⅳ型的33髋中,28髋(84.85%)可见动脉主干再通、分支增粗、实质期股骨头缺损面积缩小和静脉期股骨头染色减轻等。治疗前117病髋异常率为95.73%。经过介入治疗后,异常率为30.77%。治疗后异常率明显低于治疗前异常率(P〈0.01)。结论:介入治疗可有效改善非创伤性股骨头缺血性坏死血供异常,增加股骨头血供,具有操作简单、创伤小、疗效确切等优点。关键阗:股骨头缺血性坏死;介入治疗;数字减影血管造影 相似文献
964.
气体植物激素乙烯在植物生长发育及应对胁迫的防御反应中起重要调控作用.通过20多年的研究,利用模式植物拟南芥,勾画出一条自内质网膜受体至细胞核内转录因子的线性乙烯信号转导通路.本文概述了研究乙烯信号转导的方法及乙烯信号转导的基本过程;阐述了最新发现的乙烯信号从内质网膜传递到细胞核的分子机制,即原本定位于内质网膜上的EIN2蛋白其C端被剪切之后进入细胞核,然后通过抑制EBF1/2而稳定转录因子EIN3/EIL1;根据最近多个小组报道EIN3/EIL1直接调控除乙烯响应基因之外的其他生物学过程相关基因,提出了EIN3/EIL1可以作为网络节点整合多条信号通路的新观点;通过分析不同信号通路调控EIN3/EIL1的方式,发现不仅EIN3/EIL1的蛋白稳定性受到调控,而且其转录活性还受到诸如JAZ,DELLA等转录调节因子的调控.本文展望了未来乙烯信号转导通路的研究方向与研究热点. 相似文献
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Xitlali Aguirre-Dugua Edgar Pérez-Negrón Alejandro Casas 《Journal of ethnobiology and ethnomedicine》2013,9(1):76
Background
Selection criteria are important for analyzing domestication of perennial plant species, which experience a selection pressure throughout several human generations. We analyze the preferred morphological characteristics of Crescentia cujete fruits, which are used as bowls by the Maya of Yucatan, according to the uses they are given and the phenotypic consequences of artificial selection between one wild and three domesticated varieties.Methods
We performed 40 semi-structured interviews in seven communities. We calculated Sutrop’s salience index (S) of five classes of ceremonial and daily life uses, and of each item from the two most salient classes. We sampled 238 bowls at homes of people interviewed and compared their shape, volume and thickness with 139 fruits collected in homegardens and 179 from the wild. Morphology of varieties was assessed in fruit (n?=?114 trees) and vegetative characters (n?=?136 trees). Differences between varieties were evaluated through linear discriminant analysis (LDA).Results
Use of bowls as containers for the Day of the Dead offerings was the most salient class (S?=?0.489) with chocolate as its most salient beverage (S?=?0.491), followed by consumption of daily beverages (S?=?0.423), especially maize-based pozol (S?=?0.412). The sacred saka’ and balche' are offered in different sized bowls during agricultural and domestic rituals. Roundness was the most relevant character for these uses, as bowls from households showed a strong selection towards round shapes compared with wild and homegarden fruits. Larger fruits from domesticated varieties were also preferred over small wild fruits, although in the household different sizes of the domesticated varieties are useful. LDA separated wild from domesticated trees (p?<?0.001) according to both fruit and vegetative variables, but domesticated varieties were not different among themselves.Conclusions
The association between C. cujete bowls and traditional beverages in ritual and daily life situations has driven for centuries the selection of preferred fruit morphology in this tree. Selection of fruit roundness and volume has allowed for the differentiation between the wild variety and the three domesticated ones, counteracting gene flow among them. By choosing the best fruits from domesticated varieties propagated in homegardens, the Maya people model the domestication process of this important tree in their culture.970.
Ali R. Zomorrodi Jimmy G. Lafontaine Rivera James C. Liao Prof. Costas D. Maranas 《Biotechnology journal》2013,8(9):1090-1104
The ensemble modeling (EM) approach has shown promise in capturing kinetic and regulatory effects in the modeling of metabolic networks. Efficacy of the EM procedure relies on the identification of model parameterizations that adequately describe all observed metabolic phenotypes upon perturbation. In this study, we propose an optimization-based algorithm for the systematic identification of genetic/enzyme perturbations to maximally reduce the number of models retained in the ensemble after each round of model screening. The key premise here is to design perturbations that will maximally scatter the predicted steady-state fluxes over the ensemble parameterizations. We demonstrate the applicability of this procedure for an Escherichia coli metabolic model of central metabolism by successively identifying single, double, and triple enzyme perturbations that cause the maximum degree of flux separation between models in the ensemble. Results revealed that optimal perturbations are not always located close to reaction(s) whose fluxes are measured, especially when multiple perturbations are considered. In addition, there appears to be a maximum number of simultaneous perturbations beyond which no appreciable increase in the divergence of flux predictions is achieved. Overall, this study provides a systematic way of optimally designing genetic perturbations for populating the ensemble of models with relevant model parameterizations. 相似文献