110 research outputs found
64层CT支气管动脉成像技术在咯血诊断中的临床应用价值
目的探讨64层螺旋CT支气管动脉(brOnCHIAl ArTEry,bA)成像技术在咯血相关异常支气管动脉的优势及临床应用。方法采用64层螺旋CT对36例以咯血、胸痛为主要症状的患者行胸部CT平扫及薄层增强扫描检查。将获得的图像资料利用特殊重建技术,充分显示支气管动脉走行及其与周围组织的关系。结果本组病例36例中,右侧bA清晰显示49支,左侧bA清晰显示40支。本组36例同时进行dSA检查,将bA-CTA成像结果与bA-dSA对比,结果真阳性89支、假阳性7支,敏感度为92.7%,特异度为100%。结论 64层螺旋CTA具有较高的空间分辨率及特异性,而且可以利用各种重建技术,准确、直观地显示出bA的解剖特征,为临床提供了更多诊断信息
Research Progress on SiCBased Composite Ceramic Prepared Through a SingleSourcePrecursor Route
在碳化硅(SiC)陶瓷中引入异质元素可赋予其更优异的性能,如良好的热稳定性和独特的电磁性能。采用单源聚合物先驱体法制备陶瓷,通过合成不同结构的单; 源聚合物先驱体,可在原子尺度设计、调控陶瓷的组成和微结构等方面,达到优化陶瓷性能的目的。根据近年来的研究成果,介绍了单源聚合物先驱体制备Si-B; -C、Si-M-C (M=Ti, Zr, Hf)和Si-M-C (M=Fe, Ni)复相陶瓷的研究动态,并展望了其今后的发展趋势。The introduction of heterogeneous elements into SiC ceramics can endow; the ceramics with more excellent performances, such as high temperature; stability and unique electromagnetic properties. When preparing ceramics; through a single-source-precursor route, the composition and; microstructure of ceramics can be designed and tailored by tuning the; architecture of single-source-precursors at the atomic scale for; optimizing the ceramic performance. The research trends on Si-B-C,; Si-M-C (M = Ti, Zr, Hf) and Si-M-C (M=Fe, Ni) ceramic composites derived; from a single-source-precursor route were elaborated according to the; research achievements in recent years, meanwhile, its development trend; in the future was discussed.福建省自然科学基金; 华侨大学2016年实验教学改革与建设课
Diet composition of Difflugia tuberspinifera( testate amoeba) based on a clone library technique
瘤棘砂壳虫是东亚特有的原生动物,广泛分布于长江与珠江中下游以及福建地区的湖泊和水库,作为水生态系统的捕食者,在维持水生态系统的结构与功能方面发挥着重要作用。利用18S rrnA基因PCr扩增和克隆文库测序等分子生物学技术方法,从基因水平研究瘤棘砂壳虫的食物组成。结果表明:所获得的46条序列在97%相似度水平含有11类OTuS(OPErATIOnAl TAXOnOMIC unITS,操作分类单元),其中包括轮虫6个,桡足类5个,说明瘤棘砂壳虫的捕食类群以轮虫和桡足类为主,同时也证明单细胞生物可以直接以多细胞的后生动物为食。此外,通过克隆文库测序技术分析原生动物的食物组成比例,不仅是一种方便、高效、快速,重复性高的方法,同时也为分析原生动物的生态功能提供了一种新的视角。Difflugia is a morphologically diverse genus of the free-living shelled amoeboid protozoa that are important components of freshwater ecosystems and play crucial roles in nutrient cycles and energy flow through food webs.Difflugia tuberspinifera is an endemic species of East Asia and is widely distributed in freshwater lakes and reservoirs in China.Clearly,this species plays a critical role in maintaining the structure and function of freshwater ecosystems.However,little is known about its diet composition and predatory behavior at both species and gene levels.This testate amoeba( D.tuberspinifera) was first found in the Wujiang River,Guizhou Province,China.Subsequently,more detailed studies on its morphology and biometry have been done on natural populations from Yangtze River and Pearl River valleys,and Fujian reservoirs.Recently,Han et al.illustrated that D.tuberspinifera is an active and agile hunting carnivore that can capture swimming prey including micro-particulates,rotifers,and other metazoans.In previous studies,however,the specimen identifications were done by microscopic examination,which requires a broad and deep taxonomic knowledge and is verylaborious,time-consuming,and somewhat variable because of insufficient taxonomic resolution.In order to facilitate the identification of diet composition in D.tuberspinifera,an inexpensive,efficient,rapid and easy-to handle gene clone library has been developed for diet detection and analysis.The plankton samples were collected from the Hubian Reservoir in Xiamen city in September of 2010.Individual cells were isolated using a glass capillary under an inverted microscope and washed 3—5 times with distilled water before DNA extraction and PCR amplification.The 18 S rRNA gene was amplified by the universal eukaryotic primers,and the purified PCR products were ligated into the p GEM-T vector and transformed into Escherichia coli DH5α-competent cells.In total,46 plasmids containing target gene fragments were successfully identified and sequenced.Each sequence was compared with sequences available in the Gen Bank database using BLAST,and the closest relatives were identified for diet or food composition analysis.Finally,11 OTUs( operational taxonomic units) were identified at 97% sequence similarity level,and they belonged to either Rotifera( 52%) or Copepoda( 48%).Our results,combined with existing data,suggested that:1) the diet composition of Difflugia tuberspinifera is composed of both rotifera and copepoda species;2) unicellular protozoa are not only the food of metazoa,but they can also prey on multicellular micro-metazoa;3) molecular methods are universally applicable,and the SSU rRNA( small subunit ribosomal RNA) gene clone library is an efficient,rapid,and repeatable approach to study the diet composition of protozoa.国家自然科学基金项目(31172114;30800097); 福建省杰出青年科学基金项目(2012J06009
Spectrum-effect relationship of immunosuppressive activity of Leigongteng Duogan Tablet based on partial least squares regression analysis
目的初步探讨雷公藤多苷片免疫抑制作用及其HPlC指纹图谱间的相关性。方法采用HPlC建立7个厂家生产的雷公藤多苷片醋酸乙酯提取物的指纹图谱,选择刀豆蛋白A(COn A)刺激的小鼠脾淋巴细胞模型进行免疫抑制药效学研究,分别考察雷公藤多苷片对小鼠脾淋巴细胞增殖以及细胞因子γ干扰素(Ifn-γ)分泌的影响;采用偏最小二乘回归分析法分析谱效关系。结果建立了7个厂家生产的雷公藤多苷片的HPlC指纹图谱,从HPlC指纹图谱中提取出18个能够表征差异的特征峰。药效研究结果显示不同厂家生产的雷公藤多苷片均可显著抑制COn A诱导的小鼠脾淋巴细胞增殖和Ifn-γ的分泌(P<0.05)。偏最小二乘回归法分析结果显示,以抑制小鼠脾淋巴细胞增殖IC50值为药效指标时第1、2、6、7、17、18号峰为药效峰;以Ifn-γ分泌抑制率为指标时,第1、2、6、7、8、9、12、13号峰为药效峰。结论第1、2、6、7、8、9、12、13、17、18号峰所代表的化合物可能为雷公藤多苷片中发挥免疫抑制主要有效成分。Objective To investigate the immunosuppressive components in Leigongteng Duogan Tablet(LDT).Methods High performance liquid chromatography(HPLC) was applied to establish the fingerprint for LDT from seven manufactures.The immunosuppressive effect of LDT was observed on Con A-induced mice spleen cells, and the cell proliferation and contents of IFN-γ were recorded.Then the partial least squares regression(PLSR) analysis was used to investigate its spectrum-effect relationship.Results The HPLC fingerprint for LDT from seven manufactures was established, and 18 characteristic peaks were confirmed.The in vitro cell experimental results showed that the proliferation of mice spleen cells and secretion of IFN-γ were inhibited by all LDT significantly compared with the control group.According to the results of PLSR, No.1, 2, 6, 7, 17, and 18 peaks were strongly related to the proliferation inhibition of mice spleen cells and No.1, 2, 6, 7, 8, 9, 12, and 13 peaks were related to the secretion of IFN-γ.Conclusion The No.1, 2, 6, 7, 8, 9, 12, 13, 17, and 18 peaks are the principal immunosuppressive substances in LDT.福建省科技计划重大项目(2012I1001
基于CUMS模型探究抑郁症对细菌感染的影响及作用
目的抑郁症是一种常见的精神疾病,对患者的身体健康有着深远的影响。抑郁症与较高的细菌感染风险相关;然而,这是否是一种因果关系,以及抑郁症如何影响感染仍不清楚。因此,本研究旨在通过构建慢性不可预测轻度应激(CUMS)模型,探究抑郁表型在小鼠细菌感染中的作用。方法小鼠经CUMS诱导4周,通过行为学测试评估抑郁表型。随后,小鼠腹腔注射肺炎克雷伯菌模拟细菌感染,感染后48 h收集血清和腹腔组织。苏木精-伊红染色( HE)观察组织病理学改变,酶联免疫吸附试验(ELISA)检测炎性因子水平。此外,对感染前收集的小鼠粪便样本进行肠道菌群16S rDNA基因测序分析,并检测未感染小鼠结肠组织中NF-κB/NLRP3信号通路的表达水平。结果行为学测试结果显示,与对照组相比,CUMS小鼠体质量显著降低(P<0.000 1, t=5.426),蔗糖偏好率显著降低(P<0.001, t=4.937),游泳静止时间显著增加(P<0.001, t=16.37),旷场中央区域停留时间显著减少(P<0.01, t=3.575)。生存分析显示,与对照组小鼠相比,感染后CUMS小鼠的生存率显著降低(P<0.05)。HE染色结果显示,CUMS小鼠肝脏(P<0.05, t=4.025)、肾脏(P<0.05, t=2.828)、肠系膜(P<0.01, t=5.367)组织损伤程度明显加重。ELISA结果显示,炎症因子IL-6(P<0.01, t=3.365)、IL-1β(P<0.01, t=4.061)、TNF-α(P<0.01, t=4.460)和LPS(P<0.000 1, t=27.24)水平升高。16S rDNA测序结果显示,CUMS小鼠肠道菌群结构发生改变,与对照组小鼠明显不同,表现出菌群失调。与对照组相比,CUMS小鼠结肠组织中NF-κB(P<0.01, t=6.825)和NLRP3(P<0.001, t=9.561)的表达水平升高。结论CUMS小鼠发生更严重的细菌感染。CUMS诱导的抑郁表型可能因为破坏肠道菌群组成和激活NF-κB/NLRP3信号通路,增加了小鼠对细菌感染的易感性
节能降耗视角下的工民建施工节能技术浅析
社会经济的飞速发展,一定程度的带来了严重的环境污染及资源消耗,在这种情况下,国家提出了节能降耗号召。工民建施工中也需要利用节能技术,以降低能源消耗,保护环境资源,实现可持续发展的目标。本文就节能降耗视角下工民建施工节能技术进行探析,以供参考。</jats:p
黄土高原生物结皮中蓝藻多样性 及其生态适应性研究
黄土高原地区退耕还林还草工程实施后,以藻类、苔藓及地衣等先锋物种为主的生
物结皮广泛发育,有关其中物种组成及多样性鲜见报道。本文通过野外考察、采样、室
内培养和种类鉴定, 研究了黄土高原不同环境下生物结皮中蓝藻门植物的
Shannon-Weiner 多样性指数、物种丰富度、优势种及生物量,对比了不同环境下蓝藻门
植物多样性特征,以及水分、温度的变化对蓝藻物种组成及多样性特征的影响,探索了
蓝藻在不同环境下时空分布差异的内在原因,旨在进一步理解黄土高原不同侵蚀区藻类
的固土效应、藻结皮形成演替机制以及藻类在该区生态恢复中的作用,为生物结皮在水
土流失及荒漠化防治中的应用提供科学依据。本文首次分析了黄土高原生物结皮中蓝藻
的种类组成、多样性、时空分布特征以及时空分布的影响因素。取得如下主要结论:
1)黄土高原地区生物结皮中共发现蓝藻门植物5 目5 科13 属76 种,存在明显的
科属现象,优势科为颤藻科,优势属为颤藻属,其中丝状种类约占87%,占绝对优势。
研究区蓝藻植物隶属科属有:色球藻科(Chroococcaceae)、伪枝藻科(Scytonemataceae)、
胶须藻科(Rivulariaceae)、颤藻科(Oscillatoriaceae)和念珠藻科(Nostocaceae),色球藻属
(Chroococcus)、集胞藻属(Synechocystis)、单歧藻属(Tolypothrix)、伪枝藻属(Scytonema)、
尖头藻属(Raphidiopsis)、束藻属(Symploca)、鞘丝藻属(Lyngbya)、颤藻属(Oscillatoria)、
席藻属(Phormidium)、微鞘藻属(Microcolus)、念珠藻属(Nostoc)、鱼腥藻属(Anabaena)。
2)研究区蓝藻植物多样性指数水蚀风蚀交错区 > 水蚀区 > 风蚀区,生物量水蚀
风蚀交错区 > 水蚀区 > 风蚀区。蓝藻多样性指数在同一侵蚀区阴坡大于阳坡,同一坡
向随坡位降低逐渐升高。剖面上,蓝藻多样性随土层深度锐减,蓝藻主要分布在0-2cm
土层,0-0.5cm土层的蓝藻种类占全部土层蓝藻种类的85%,0-2cm土层占总蓝藻种类的
98%;2cm以下土壤中蓝藻种类很少。不同侵蚀区蓝藻Shannon-Weiner多样性指数表现
为:水蚀风蚀交错区 > 水蚀区 > 风蚀区,依次为2.22 bit,2.20 bit和2.14 bit,水蚀风
蚀交错区和水蚀区蓝藻多样性指数差异不显著(P>0.05),但均与风蚀区差异显著
(P<0.05)。蓝藻丰富度及优势种在不同侵蚀区也各不相同,水蚀风蚀交错区蓝藻丰富
度最高(39种),以阿氏鞘丝藻(Lyngbya allorgei)为优势种;水蚀区次之(26种),以含钙席藻(Phormidium calciola)为优势种;风蚀区最低(20种),以颗粒颤藻(Oscillatoria
granulata)为优势种。与蓝藻多样性指数的变化趋势一致,藻类的生物量在不同侵蚀区表
现为:水蚀风蚀交错区>水蚀区>风蚀区。在同一侵蚀区,阴坡蓝藻多样性指数大于阳坡;
同一坡向随坡位的降低表现出逐渐升高的趋势,其中,阴坡的蓝藻多样性指数随坡位的
降低表现为坡上2.57 bit < 坡中2.67 bit< 坡下2.69 bit。阳坡的多样性指数与阴坡略有不
同,随坡位的降低表现为坡中2.46 bit < 坡上2.54 bit < 坡下2.65 bit;阳坡和阴坡的蓝藻
优势种分别为狭细席藻(Phormidium angustissimum)和阿氏鞘丝藻(Lyngbya allorgei)。剖
面上,蓝藻主要分布在0-2 cm土层,0-0.5 cm土层的蓝藻种类占全部土层蓝藻种类的85%,
0-2 cm土层占总蓝藻种类的98%;蓝藻多样性随土层深度锐减,2 cm以下土壤中蓝藻种
类很少。其中,0-0.5 cm土层的蓝藻多样性均极显著高于其下层(P<0.01),0.5-1 cm 土
层与下层1-2 cm、2-5 cm之间的差异均达显著水平(P<0.05),其余土层之间的差异均不
显著(P>0.05)。
3)蓝藻植物多样性随着发育年限及季节变化,表现出明显的年际和年内动态特征。
随着退耕年限的增长,多样性指数呈上升的趋势,至发育8a以上的,其多样性逐渐稳定;
年内蓝藻多样性指数雨季中>雨季前>雨季末。
研究区蓝藻多样性指数农地(CK)最低2.08 bit,退耕20a以上最高2.65 bit,其多样性
指数与农地之间的差异均达显著水平(P<0.05),退耕8a以上与退耕0.5a的其蓝藻多样性
指数之间均差异显著(P<0.05)。不同发育年限的生物结皮中蓝藻的丰富度中,农地最
低(21种),退耕8a最高(32种)。退耕0.5a这段时期是蓝藻的快速增长期,退耕8a的生
物结皮中蓝藻丰富度达到最高。不同季节的蓝藻Shannon-Weiner物种多样性指数表现为:
雨季中>雨季前>雨季末,依次为2.96 bit,2.85 bit和2.66 bit。雨季中与雨季末多样性指
数差异显著(P<0.05),其余差异不显著(P>0.05);蓝藻的丰富度与多样性指数的变化
趋势一致,雨季中最高(35种),雨季前(32种)次之,雨季末(26种)最少。雨季前
和雨季中的生物结皮中蓝藻的优势种分别为狭细席藻和阿氏鞘丝藻,雨季末的优势种与
雨季前相同。然而,藻类的生物量的季节变化为雨季前>雨季中>雨季末。
4)蓝藻植物多样性与环境水分、温度变化有关。降水量与蓝藻多样性指数及丰富
度之间呈正相关关系,是影响蓝藻多样性的首要环境因子。温度对蓝藻多样性影响次之。
与蓝藻多样性相关的土壤理化属性有土壤全氮,土壤全磷和土壤速效磷。其中,土壤全
氮与蓝藻多样性之间呈极显著负相关关系。土壤全磷和速效磷与蓝藻多样性均呈显著负
相关关系。不同的蓝藻对环境因子的响应不同,具有不同的生态适应性。
关键词:蓝藻;多样性;时空分布;环境因子;影响因素</p
Overview of the Etiology, Diagnosis and Treatment History of Critically Ill Pregnant Women
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