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21.
目的:探讨应用脾动脉结扎法行全腹腔镜巨脾切除术的安全性、可行性及手术技巧。方法:将2010年1月1日至2012年1月1日因肝硬化门脉高压脾机能亢进巨脾患者随机分为腹腔镜脾切除(Laparoscopic Splenectomy,LS)组及开腹脾切除(OpenSplenectomy,OS)组,比较两组的临床特征及围手术期差异。结果:LS组与OS组在性别组成、术前肝功能child分级、年龄组成及脾脏长径方面均无统计学意义。LS组手术时间比OS组略长,但无统计学意义,LS组术中出血量明显低于OS组(P<0.01),LS组术后进食、术后排气、引流管拔除及出院时间均明显早于OS组(P<0.01)。结论:腹腔镜脾切除术为治疗门脉高压巨脾的一种有效、安全、可行的手术方式。  相似文献   
22.
Biomolecular computing is an emerging field at the interface of computer science, biological science and engineering. It uses DNA and other biological materials as the building blocks for construction of living computational machines to solve difficult combinatorial problems. In this article, notable advances in the biomolecular computing are reviewed and challenges associated with this multidisciplinary research are addressed. Finally, several perspectives are given based on the review of biomolecular computing.  相似文献   
23.
丁宁  易征  周凯  曹彦 《生物磁学》2011,(8):1458-1460
目的:研究脾切除对肝纤维化大鼠肝脏TGFβ1的表达和血清TGFβ1水平的影响,探讨脾切除在肝纤维化中的意义。方法:用CCL4建立50例肝纤维化大鼠模型。于建模第3周,6周,及8周分别取大鼠肝脏和脾脏标本。用免疫组化SP方法测定其TGFβ1的表达,HE和姬姆萨染色检测肝纤维化。应用双抗体夹心ELISA方法测定15例模型大鼠行脾脏切除前后的血清TGFβ1水平,以及15例对照组大鼠的血清TGFβ1水平,并于术后4周取两组大鼠的肝脏标本,用免疫组化SP方法测定其TGFβ1的表达。应用CMIAS8彩色图像系统对阳性目标进行分析和处理。结果:随着肝纤维化程度的进展,大鼠肝脏和脾脏TGFβ1的表达也随之增加(P〈0.01)。脾切除组大鼠其血清TGF-β1的水平显著低于对照组大鼠(P〈0.05),且脾切除组大鼠肝脏TGFβ1的表达低于对照组大鼠(P〈0.05)。结论:脾切除术在一定程度上可延缓肝纤维化的发展。  相似文献   
24.
摘要 目的:探讨肿块型乳腺癌的超声造影(CEUS)特征及定量参数与可溶性E-钙黏蛋白(sE-cad)、可溶性肿瘤坏死因子受体P55(sTNFR-P55)相关性研究,并探讨其对肿块型乳腺癌的诊断价值。方法:选取2019年1月至2021年1月于本院诊治并行CEUS检查的162例乳腺肿块患者,根据病理结果分为肿块型乳腺癌组(82例)和良性组(80例),另选取本院体检健康的80例女性作为对照组。三组均行血清sE-cad、sTNFR-P55水平检测。比较肿块型乳腺癌组与良性组CEUS特征及定量参数的差异,采用Pearson相关分析肿块型乳腺癌患者CEUS定量参数与血清sE-cad、sTNFR-P55水平的相关性。对CEUS、血清sE-cad、sTNFR-P55水平单独或三者联合诊断的方式采用敏感度、特异度、准确性、阳性预测值、阴性预测值指标表达。结果:肿块型乳腺癌组大部分表现为增强后形态不规则、高增强、向心性灌注、造影剂分布不均匀以及呈慢出型的强化方式,且所占比例显著高于良性组(P<0.05)。与良性组相比,肿块型乳腺癌组CEUS定量参数TTP、G显著降低(P<0.05),而PI、K显著升高(P<0.05)。肿块型乳腺癌组血清sE-cad、sTNFR-P55水平显著高于良性组、对照组(P<0.05),且良性组血清sE-cad、sTNFR-P55水平还显著高于对照组(P<0.05)。肿块型乳腺癌患者的CEUS定量参数TTP、G与血清sE-cad、sTNFR-P55水平呈负相关(P<0.05);而PI、k与血清sE-cad、sTNFR-P55水平呈正相关(P<0.05)。CEUS联合血清sE-cad、sTNFR-P55水平诊断肿块型乳腺癌的准确度、敏感度、特异度、阳性预测值、阴性预测值最高。结论:CEUS特征及定量参数对肿块型乳腺癌具有一定的鉴别诊断价值,而且CEUS定量参数与血清sE-cad、sTNFR-P55水平具有一定的相关性,说明CEUS定量参数可在一定程度上可反映乳腺癌的恶性生物学行为;同时CEUS联合血清sE-cad、sTNFR-P55水平检测有助于提高对肿块型乳腺癌的鉴别诊断价值,进一步为临床医生的定性判断提供更加科学的影像学依据。  相似文献   
25.
The advent of massive parallel sequencing of immunopurified chromatin and its determinants has provided new avenues for researchers to map epigenome-wide changes and there is tremendous interest to uncover regulatory signatures to understand fundamental questions associated with chromatin structure and function. Indeed, the rapid development of large genome annotation projects has seen a resurgence in chromatin immunoprecipitation (ChIP) based protocols which are used to distinguish protein interactions coupled with large scale sequencing (Seq) to precisely map epigenome-wide interactions. Despite some of the great advances in our understanding of chromatin modifying complexes and their determinants, the development of ChIP-Seq technologies also pose specific demands on the integration of data for visualization, manipulation and analysis. In this article we discuss some of the considerations for experimental design planning, quality control, and bioinformatic analysis. The key aspects of post sequencing analysis are the identification of regions of interest, differentiation between biological conditions and the characterization of sequence differences for chromatin modifications. We provide an overview of best-practise approaches with background information and considerations of integrative analysis from ChIP-Seq experiments.  相似文献   
26.
目的:探讨大容量全肺灌洗术(WLL)对尘肺患者肺功能、血气指标及炎症因子的影响。方法:选取2016年10月到2019年10月在我院接受治疗的尘肺患者48例作为本次研究对象,根据随机数字表法将患者分为WLL组和常规组各24例,给予常规组患者汉防己甲素、乙酰半胱氨酸泡腾片等常规药物治疗,在常规组的基础上给予WLL组患者联用双侧同期WLL治疗。分别于治疗前3天和治疗后2周检测并对比两组患者白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平、血氧分压(PaO_2)、动脉血二氧化碳分压(PaCO_2)、肺泡动脉氧分压差(PA-aO_2)、用力肺活量(FVC)、一秒用力呼气容积与用力肺活量的比值(FEV1/FVC%)及最大通气量与预计值的比值(MVV%)。结果:两组治疗前肺功能指标、血气指标、炎症因子水平比较差异均无统计学意义(P0.05),两组治疗后PA-aO_2较治疗前水平明显降低,FVC、FEV_1/FVC%、MVV%、PaO_2、PaCO_2均较治疗前显著上升,IL-6、TNF-α水平与治疗前比较均明显降低(P0.05);治疗后两组PA-aO_2比较差异无统计学意义(P0.05),治疗后WLL组的FVC、FEV_1/FVC%、MVV%、PaO_2、PaCO_2均高于常规组,IL-6、TNF-α水平均低于常规组,差异均有统计学意义(P0.05)。结论:WLL可明显改善尘肺患者肺功能和血气指标,降低患者血清内IL-6、TNF-α的水平,减轻炎症反应,临床疗效确切,值得临床推广应用。  相似文献   
27.
慕课、微课在地方应用型高校“发酵工程”课程教学中的   总被引:1,自引:1,他引:1  
林标声  沈绍新 《微生物学通报》2015,42(12):2475-2481
慕课、微课是信息时代发展的产物,是将来高等教育的发展方向。探索将慕课、微课引入到地方应用型高校的“发酵工程”教学改革与探索,以期将其作为“发酵工程”课堂教学的补充与延伸,形成一种兼顾课堂教学和个性化教学的新模式,最大限度地促进学生的个性化学习。一年多的教学改革探索表明慕课、微课的课程教学改革得到了学生和同行教师的认可,确实有利于提升学生的各项学习成绩,尤其是实践成绩的提升达到了显著水平(P<0.05),符合培养应用型人才的教学目的,值得地方高校借鉴。  相似文献   
28.
29.
Summary Upper Jurassic (Malm δ to ζ1) massive limestones (‘algal-sponge-reefs, sponge-reefs, reef-complexes, reefs, algal-sponge-bioherms, biolithites, Massenkalk, bioherms, Stillwasser-Mudmounds’) were analyzed in the Southern Swabian Alb, the Southern Franconian Alb and in drilling wells in the Molasse basin (Southern Bavaria). This analysis was carried out within the frame of a multidisciplinary DFG-study with the objective of decifering the controls on the development of Upper Jurassic spongiolites, their three-dimensional distribution, their characteristic faunal composition, and the diagenetic trends of the different primary facies. The data base consists of detailed facies mapping in the areas of the Eybtal and the Blautal (1300 samples) as well as comparative studies in the Upper Donautal (Swabian Alb) and the Southern Franconian Alb (400 samples). All together about 500 thin sections were studied. The distribution of the most important components (ooids, intraclasts, peloids, corals, sponges, sponge spicules, cyanobacterial crusts, brachiopods, molluscs, echinoids, bryozoans, serpulids,Terebella, Tubiphytes), and diagenetic features (dolomite, dedolomite, silicification, stylolites, clay flasers, hematite patches) results in a spatial distribution pattern of facies types. The largest part (70 %) of the massive limestones consists of a peloid-lithoclast-ooid sand facies rich in completely or partly micritized ooids. These ooids, especially in beds of the Malm δ to ε, might be the clue to a reinterpretation of the water depth. True biogenic constructions occur (about 30 % of the volume; sponge-algalmudmounds, algal-sponge-boundstones, and brachiopod-algal-sponge-mounds) within and at the margins of this facies and are interpreted as platform sands. The spatial distribution of the buildups in relation to the sand facies was probably controlled by hydrodynamic conditions. In addition, zoned sponge-algal-mounds occur in intraplatform channels and nodular sponge-algal-mudmounds in the marly basin sediments between platform sand areas. Breccias and slumpings in beds older than the Malm ζ have to be reinterpreted. Most of the breccias found originated from the flanks of the sand platforms, reflecting the faunal composition of the algal-sponge-boundstones which stabilized the flanks. Breccias of this composition occur throughout the Malm δ-ζ1 and differ markedly in their composition from the sand facies. The boundary breccia (Malm ε/ζ1) is interpreted as marking a regressive maximum. The increasing growth of buildups, rich in brachiopods in the Malm ζ1, is ascribed to an increase of reef growth at the beginning of a transgression. Detailed facies analyses necessary for the reconstruction of the spatial distribution of different facies types are in progress. Most of the older data on faunal distributions cannot be used for detailed facies analysis because they differentiated only between massive facies and bedded facies. Therefore Upper Jurassic limestones of Southern Germany should be restudied in order to recognize the volumetric importance of sand facies and buildups within massive limestones.  相似文献   
30.
BackgroundA previous study demonstrated that nearly 40%–60% of brain Aβ flows out into the peripheral system for clearance. However, where and how circulating Aβ is cleared in the periphery remains unclear. The spleen acts as a blood filter and an immune organ. The aim of the present study was to investigate the role of the spleen in the clearance of Aβ in the periphery.MethodsWe investigated the physiological clearance of Aβ by the spleen and established a mouse model of AD and spleen excision by removing the spleens of APP/PS1 mice to investigate the effect of splenectomy on AD mice.ResultsWe found that Aβ levels in the splenic artery were higher than those in the splenic vein, suggesting that circulating Aβ is cleared when blood flows through the spleen. Next, we found that splenic monocytes/macrophages could take up Aβ directly in vivo and in vitro. Splenectomy aggravated behaviour deficits, brain Aβ burden and AD‐related pathologies in AD mice.ConclusionOur study reveals for the first time that the spleen exerts a physiological function of clearing circulating Aβ in the periphery. Our study also suggests that splenectomy, which is a routine treatment for splenic rupture and hypersplenism, might accelerate the development of AD.  相似文献   
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