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1.
The crenistria Limestone is a set of three autochthonous massive limestone beds occurring with great lithological persistence in the Kulm Facies (cd III , upper Viséan) of the eastern Rheinisches Schiefergebirge. Microfacies analysis reveals mainly minipeloidal fabrics and homogeneous micrite. Uncrushed, sediment-filled conchs of goniatites represent loci of sheltered preservation of primary carbonate textures. Calcified radiolarians are abundant, forming between 20 and 80% of total rock volume. The alleged algal genus Rectangulina is common in the crenistria Limestone. It is reinterpreted to represent the faeces of goniatites. For the first time the presence of in situ preserved sponges is reported. They can be recognized as delicate networks of microsparitic needles embedded in peloidal fabrics. Hexactinellids with primary spicule arrangements can be found embedded in homogeneous micrite. The carbonate forming the limestone beds was produced microbially during decomposition of soft tissue of the radiolarians and sponges. During the cd III , anoxia in the bottom waters of the Kulm Basin persisted for long periods due to stable density stratification of the water column under humid climatic conditions. Oxic conditions in the bottom waters during formation of the limestone are indicated by bioturbation, the presence of sponges and the high Mn-contents of the carbonate. The latter derived from reduction of Mn-oxides during microbial carbonate formation.  相似文献   
2.
A HPLC method has been developed to measure phosphatidylcholine (PC) containing reactive carbonyl functions in the sn-acyl residue in order to study processes in which such reactive carbonyls can be formed due to e.g. oxidative fragmentation. The method has been applied to determine PC-bound carbonyls as 2, 4-dinitrophenylhydrazones (DNPH) in plasma of burn patients. Plasma from healthy volunteers served as controls. Additionally, in vitro oxidation experiments (A: plasma, buffer diluted; B: plasma + iron-EDTA complex and C: plasma + iron-EDTA complex + H2O2) have been performed to obtain and to identify 2, 4-dinitrophenylhydrazine derivatizable carbonyl functions in plasma PC. Both, the PC-aldehydes and PC-aldehyde DNPH derivatives were cleavable with phospholipase C. Quantification was based on thin-layer chromatography purified soybean phosphatidylcholine, which was identically oxidized and derivatized as the plasma lipids in vitro.  相似文献   
3.
BackgroundIncreased incidence of antibiotic-resistant species calls for development of new types of nano-medicine that can be used for healing of bacteria-caused wounds, such as diabetic foot ulcer. As diabetic patients have inefficient defense mechanism against reactive oxygen species (ROS) produced in our body as a by-product of oxygen reduction, the process of wound healing takes longer epithelialisation period. Ceria nanoparticles (CNPs) are well-known for their antibacterial and ROS-scavenging nature. Yet till now no significant effort has been made to conjugate ceria nanoparticles with drugs to treat diabetic wounds.MethodsIn this experiment, CNPs were synthesized in-house and clindamycin hydrochloride was loaded onto it by physical adsorption method for reactive oxygen species responsive drug delivery. Various physico-chemical characterisations such as Transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, Energy dispersive X-ray, Thermogravimetric study etc. were performed to affirm the formation of both nanoceria along with drug encapsulated nanoceria.ResultsBoth of these as-prepared formulations inhibited the growth of Gram-positive as well as Gram-negative bacteria confirmed by Disk diffusion study; exhibiting their antibacterial effect. In-vitro drug release study was carried out in physiological environment both in absence and presence of hydrogen peroxide solution to test the reactive ROS-responsiveness of the drug loaded nanocomposites. It also exhibited faster wound healing in diabetes-induced rats. Therefore, it could successfully lower the amount of serum glucose level, inflammation cytokines, hepatotoxic and oxidative stress markers in diabetic rats as confirmed by various ex vivo tests conducted.ConclusionThus, drug loaded ceria nanoparticles have the potential to heal diabetic wounds successfully and can be considered to be useful for the fabrication of appropriate medicated suppositories beneficial for diabetic foot ulcer treatment in future.  相似文献   
4.
外科深部真菌感染的病原学分析   总被引:1,自引:0,他引:1  
目的分析外科住院患者合并真菌感染状况。方法分离的真菌用API 20C AUX真菌鉴定条,用ATB FUNGUS-2进行药敏试验。结果真菌的种类分布中第1位是白色念珠菌占53%,第2位是热带念珠菌占20%,第3位是光滑念珠菌占14%,第4位是近平滑念珠菌占4%,第5位是其余念珠菌占2%;真菌在外科各区分布中,外科ICU占42%,移植外科占25%;真菌在各类标本分布中,痰占43%,尿液占13%,粪便占10%,引流液占9%,血液占7%;真菌对药物5-氟胞嘧啶、两性霉素B、氟康唑、伊曲康唑的药物敏感性分别是93%、98.9%、90.8%、59.8%。结论外科真菌感染集中在重症病区(ICU),分离的致病真菌主要是白色念珠菌、热带念珠菌、光滑念珠菌,真菌对两性霉素B敏感性最高。  相似文献   
5.
草原火烧严重度燃烧指数的适用性比较分析   总被引:1,自引:0,他引:1  
宫大鹏  李炳怡  刘晓东 《生态学报》2018,38(7):2434-2441
基于遥感影像的燃烧指数被广泛应用于火烧严重度(fire severity)研究,选取适宜燃烧指数定量评估草原火烧严重度,对草原生态系统植被的恢复与管理具有重要意义。以呼伦贝尔草原火烧迹地为研究区域,基于landsat8 OLI影像分别构建4种燃烧指数(NBR、NSTV1、d NBR和Rd NBR)与综合燃烧指数(CBI)的回归模型并进行精度验证,对比分析不同燃烧指数识别草原火烧严重度等级的能力。结果表明:在燃烧指数与CBI构建的回归模型中,d NBR指数的相关性(n=70,R~2=0.856)最高;4种燃烧指数识别火烧严重度的精度存在差异,中度火烧区域(1CBI≤2)内,NSTV1指数识别精度最高,未过火(CBI=0)、轻度火烧(0CBI≤1)和重度火烧(2CBI≤3)区域内,d NBR指数识别精度均表现最好,分别为80%、62.5%和100%;基于不同燃烧指数的草原火烧严重度制图中,d NBR指数的总体精度同样高于其他燃烧指数,为82.1%,Kappa系数高达0.76。综上所述,d NBR指数是草原火烧严重度分析与评价的适宜遥感指数。  相似文献   
6.
Quantitative structure–activity relationship (QSAR) analysis uses structural, quantum chemical, and physicochemical features calculated from molecular geometry as explanatory variables predicting physiological activity. Recently, deep learning based on advanced artificial neural networks has demonstrated excellent performance in the discipline of QSAR research. While it has properties of feature representation learning that directly calculate feature values from molecular structure, the use of this potential function is limited in QSAR modeling. The present study applied this function of feature representation learning to QSAR analysis by incorporating 360° images of molecular conformations into deep learning. Accordingly, I successfully constructed a highly versatile identification model for chemical compounds that induce mitochondrial membrane potential disruption with the external validation area under the receiver operating characteristic curve of ≥0.9.  相似文献   
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8.
为实现高通量识别新的药物-长链非编码RNA(Long non-coding RNA, lncRNA)关联,本文提出了一种基于图卷积网络模型来识别潜在药物-lncRNA关联的方法DLGCN(Drug-LncRNA graph convolution network)。首先,基于药物的结构信息和lncRNA的序列信息分别构建了药物-药物和lncRNA-lncRNA相似性网络,并整合实验证实的药物-lncRNA关联构建了药物-lncRNA异质性网络。然后,将注意力机制和图卷积运算应用于该网络中,学习药物和lncRNA的低维特征,基于整合的低维特征预测新的药物-lncRNA关联。通过效能评估,DLGCN的受试者工作特性曲线下面积(Area under receiver operating characteristic, AUROC)达到0.843 1,优于经典的机器学习方法和常见的深度学习方法。此外,DLGCN预测到姜黄素能够调控lncRNA MALAT1的表达,已被最近的研究证实。DLGCN能够有效预测药物-lncRNA关联,为肿瘤治疗新靶点的识别和抗癌药物的筛选提供了重要参考。  相似文献   
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10.
I. Raskin  H. Kende 《Planta》1984,162(6):556-559
Submergence induces rapid internodal elongation in deep-water rice (Oryza sativa L. cv. Habiganj Aman II). We investigated the metabolic activities which help to support such fast growth. Three days of submergence in water under continuous light led to the mobilization of 65% of the starch from those regions of rice internodes which had been formed prior to submergence. Disappearance of starch was accompanied by a 70-fold enhancement of amylolytic activity. Similar increases in amylolytic activity were detected in response to ethylene and gibberellic acid. Submergence also caused a 26-fold increase in the translocation of newly synthesized photosynthetic assimilates from the leaves to the internodes and younger regions of the culms. These physiological processes are likely to provide the metabolic energy required for internodal elongation in response to submergence.Abbreviation GA3 gibberellic acid  相似文献   
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