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991.
目的 采用气相色谱法(GC)结合气相色谱-质谱(GC-MS)联用技术,对3种不同来源共26批鱼肝油样品中的脂肪酸成分进行测定。方法 通过氢氧化钾-甲醇碱催化法对鱼肝油样品进行甲基衍生化预处理,选用极性毛细管柱对样品中的衍生化产物脂肪酸甲酯进行分离,后经气相色谱仪-氢火焰离子化检测器(GC-FID)和气相色谱-质谱(GC-MS)联用仪进行分析检测。利用对照品定位法结合NIST谱库检索准确鉴定出棕榈酸、棕榈油酸、油酸、亚油酸、二十碳五烯酸(eicosapentaenoic acid,EPA)和二十二碳六烯酸(docosahexaenoic acid,DHA)等14种脂肪酸,并通过面积归一化法对这14种脂肪酸进行定量分析。结果 这14种脂肪酸在国内鱼肝油中的含量与模拟天然鱼肝油和进口鱼肝油样品中的含量存在较大差异。其中,EPA和DHA等脂肪酸在模拟天然鱼肝油和进口鱼肝油样品中的含量远高于其在国内鱼肝油样品中的含量,而亚油酸在国内鱼肝油样品中的含量却高达44%以上,10倍于其在另外2种鱼肝油样品中的含量。结论 不同来源的鱼肝油样品中的脂肪酸成分不尽相同,可根据脂肪酸的组成区别鱼肝油样品中是否添加天然鱼肝油成分。 相似文献
992.
目的:通过系统检索中英文医学期刊发表的中医药干预中风的临床随机对照试验,分析年度证据产出情况。方法:CNKI、Sino Med、维普、万方、Cochrane library、Pub Med、Embase、Web of Science等数据库,检索时限为2018年1月1日至2018年12月31日。收集中医药干预中风的临床随机对照试验。对全年发文概况、期刊分布、省份和单位分布、疾病类型、干预措施、结局指标以及干预疗程等内容进行描述性分析。结果:2018年发表的中医药干预中风的RCT共有1 084篇研究中,近90%研究重点是缺血性中风;近70%的研究采用的干预措施是中药方剂,剂型主要是汤剂;共涉及69个口服中成药和18个中药注射剂。干预疗程以2和4周为主,占64. 91%,疗程≤6个月的研究占98. 32%。神经功能、运动功能、生活能力以及生命质量评价为研究关注的结局指标。结论:中医药干预中风研究年度发文较多,但干预措施较为分散,干预疗程显著不足,研究设计存在较多问题。建议整合区域研究力量,围绕重点问题进行协同攻关,提高研究质量,减少研究浪费。 相似文献
993.
“健康中国”战略对我国慢性病管理模式的发展提出了更高要求。通过文献资料及逻辑分析等研究方法,对我国慢性病管理模式的价值意蕴、慢性病管理的典型模式及慢性病管理存在的问题等方面进行审视,探索“健康中国”背景下我国慢性病管理模式发展的优化路径。研究认为,我国慢性病管理存在慢性病防治健康教育力度不足、专业医务人员数量紧缺、慢性病管理信息平台建设不平衡及慢性病管理体系不健全等突出问题。基于此,结合“健康中国”战略的发展要求,提出优化路径:行稳致远——提高居民健康教育的力度,强基固本——推进基层医疗卫生队伍的建设,互联互通——加快慢性病管理信息平台的开发,统筹兼顾——搭建慢性病管理的分级诊疗体系。 相似文献
994.
Bilateral Common Carotid Artery Occlusion in Spontaneously Hypertensive Rats: A Feasible Animal Model for Ocular Ischemic Syndrome
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Yacong Wang Yuhua Fan Lihong Zhang Yi‐Xiang J. Wang Wei Qi Willmann Liang Chunmei Wang David T.W. Yew Cunxi Ye Ou Sha 《Anatomical record (Hoboken, N.J. : 2007)》2016,299(6):806-814
The purpose of this study was to investigate the feasibility of inducing ocular ischemic syndrome in spontaneously hypertensive rats. Hypertensive and normotensive Wistar–Kyoto rats had bilateral occlusion or sham surgery. They were divided into 4 groups: (1) hypertensive‐ischemia, (2) hypertensive‐sham, (3) normotensive‐ischemia, and (4) normotensive‐sham. Four months after the operation, the global changes of the eye and pupillary light reflex were assessed. Then each rat was perfused, and randomly one of the bulbuses oculi was prepared as retinal flat mounts for investigation of vascular changes. The opposite eyeball was prepared as a paraffin section for observation of the linear density of retinal ganglion cells and for thickness measurement. One hypertensive‐ischemia rat had a cataract in one eye and another rat in the same group had bulbus oculi collapse in one eye. The light reflex disappeared in 13.33% of hypertensive‐ischemia rats, and the rest of the hypertensive‐ischemia rats and normotensive‐ischemia rats had slow reflex. Compared with the respective controls, the peripheral retinal vascular network in hypertensive‐ischemia and normotensive‐ischemia rats was sparse; linear density of the retinal ganglion cells was significantly reduced; and the retinal thickness was reduced. Compared with normotensive‐ischemia rats, the hypertensive‐ischemia rats demonstrated more severe changes. After bilateral common carotic artery occlusion, the eyes of hypertensive rats developed various pathological changes similar to those of ocular ischemic syndrome. In conclusion, an animal model for ocular ischemic syndrome can be created by bilateral common carotid artery occlusion in spontaneously hypertensive rats. Anat Rec, 299:806–814, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
995.
When one uses USAF target to calibrate the resolution of an imaging system, the periodicity of the smallest resolvable line should be used to define the limit. However, in the original paper, the line width of the resolution target was used to characterize the resolution of our microscope system, resulting in an overestimation of the performance of the imaging system. In this erratum, we correct the parts that state incorrect resolution and also re-evaluate the performance of our micoscope.OCIS codes: (120.4820) Optical systems, (170.0180) Microscopy, (170.4730) Optical pathologyIn section 4 of the original paper [1], we characterized the resolution of our imaging system using a USAF target. In the experiment, group 9 element 3 (0.78 μm line width) of the resolution target was resolved, and we stated that ‘This establishes the resolution of our prototype system under the quasi-monochromatic 530 nm illumination, as 0.78 μm over the entire FOV.’ Here, we correct the statement as follows: This establishes the resolution of our prototype system under the quasi-monochromatic 530 nm illumination as 1.56 μm over the entire FOV. We also stated that ‘the effective pixel size at the object plane should be less than 0.39 μm (0.78 μm divided by 2).’ We correct the statement as: the effective pixel size at the object plane should be less than 0.78 μm (1.56 μm divided by 2).Because of the change of the resolution, the space-bandwidth product (SBP) of the imaging system needs to be recalculated. The imaging system has a field-of-view (FOV) of 10 mm × 7.5 mm, with effective pixel size of 0.78 μm x 0.78 μm, resulting in an SBP of 0.12 gigapixel. We hereby state that the previous estimation of a 0.5 gigapixel microscopy is incorrect. Instead, we got a microscope system with 0.12 gigapixel. In the following paragraphs, we listed all the incorrect statements and correct them accordingly.In the abstract, we stated that: ‘We show that such an imaging system is capable of capturing a 10 mm × 7.5 mm FOV image with 0.78 μm resolution, resulting in more than 0.5 billion pixels across the entire image... To demonstrate its application, 0.5 gigapixel images of histology slides were acquired using this system.’ We correct the statement as: We show that such an imaging system is capable of capturing a 10 mm × 7.5 mm FOV image with 1.56 μm resolution, resulting in more than 0.12 billion pixels across the entire image... To demonstrate its application, 0.12 gigapixel images of histology slides were acquired using this system.In the second last paragraph of section 1, we stated that: ‘We show that such a system is capable of capturing a 0.5-gigapixel pixel image with a FOV of 75 mm2 and a resolution of 0.78 μm. Remarkably, the CCTV lens has a SBP of at least 0.5 gigapixel (109pixels), two orders of magnitude larger than conventional microscope objectives.’ We correct the statement as: We show that such a system is capable of capturing a 0.12-gigapixel pixel image with an FOV of 75 mm2 and a resolution of 1.56 μm. Remarkably, the CCTV lens has an SBP of at least 0.12 gigapixel (109pixels), one order of magnitude larger than conventional microscope objectives.The title of section 2 was: ‘The prototype setup of the 0.5 gigapixel microscopy imaging system’, but it should be ‘The prototype setup of the 0.12 gigapixel microscopy imaging system’.In section 6, we stated that ‘In summary, we report a wide-FOV (10 mm × 7.5 mm) microscopy system which can generate a 0.5 gigapixel image with 0.78 μm resolution across the entire FOV.’ We correct the statement as: In summary, we report a wide-FOV (10 mm × 7.5 mm) microscopy system which can generate a 0.12 gigapixel image with 1.56 μm resolution across the entire FOV. We stated that: ‘Compared to typical 10 × and 4 × objectives, our system has both superior SBP and resolution.’ We correct the statement as: Compared to typical 4 × objectives, our system has both superior SBP and resolution.We also need to relabel the position of our CCTV lens in the space-bandwidth product plot shown in Fig. 7. The relabeled coordinate is shown as follows:Open in a separate windowFig. 7The SBP-resolution summary for microscope objectives and our current CCTV lensbased system. 相似文献
996.
目的 观察二甲双胍对骨肉瘤MG63细胞的迁移侵袭能力的影响.方法 以骨肉瘤MG63细胞株为研究对象,二甲双胍处理后分别采用transwell小室法检测细胞迁移和侵袭能力的变化,采用明胶酶谱实验检测基质金属蛋白酶2(MMP-2)和MMP-9的活性,采用real-time PCR法检测细胞中埃兹蛋白(Ezrin) mRNA的表达,采用Western blot检测Ezrin蛋白的表达;Li-pofectamine 2000转染Ezrin质粒到细胞中观察其对二甲双胍诱导的细胞迁移侵袭抑制及对下游信号通路的影响.结果 二甲双胍可显著抑制MG63细胞的迁移和侵袭,并降低MMP-2和MMP-9的酶活性.用药48 h后,MG63细胞内Ezrin的mRNA和蛋白水平均明显下降,且上调Ezrin可减弱二甲双胍诱导的骨肉瘤细胞迁移和侵袭抑制及二甲双胍诱导的MAPK/Erk信号通路抑制.结论 二甲双胍可抑制MG63细胞的迁移和侵袭能力,可能是通过下调Ezrin和MAPK/Erk信号通路而实现. 相似文献
997.
目的 观察静脉注射小剂量抗组胺药盐酸异丙嗪对芬太尼诱发咳嗽的影响.方法 选200例拟行全身麻醉择期手术患者,术前分为4组:对照组和试验1、2、3组,麻醉诱导前各组分别给予0.1 mL/kg的4种药液:0.9%盐水,0.5、1.0、1.5mg/mL异丙嗪,所有患者麻醉诱导注射芬太尼3μg/kg,记录注射芬太尼2 min内患者咳嗽发生情况,包括咳嗽发生次数、强度、时间以及收缩压、舒张压、心率情况.结果 试验1、2、3组咳嗽发生率为16%、12%、10%,与对照组(32%)相比明显下降(P<0.05);试验1、2、3组轻度咳嗽发生率与对照组相比明显下降(P<0.05);各组中度和重度咳嗽发生率比较差异无统计学意义(P>0.05);发生咳嗽的平均时间4组比较差异无统计学意义(P>0.05).T4时点对照组、试验2组、试验3组的舒张压升高较试验1组明显,差异有统计学意义(P<0.05),试验3组心率增快高于对照组和试验1组、试验2组,差异有统计学意义(P<0.05).结论 预注盐酸异丙嗪可降低芬太尼诱发咳嗽的发生率. 相似文献
998.
目的 使用ELIspot法观察中药红曲对强直性脊柱炎(ankylosing spondylitis)患者外周血单个核细胞分泌TNF-α的影响.方法 采集强直性脊柱炎病情活动期患者(均符合1984年美国风湿病协会关于强直性脊柱炎的诊断)的外周血,分离外周血单个核细胞(peripheral blood mononuclear cells,PBMCs),制成细胞悬液,以每孔2.5 ×105个细胞种植到包被有抗肿瘤坏死因子α(tumor necrosis factor α,TNF-α)抗体的96孔酶联免疫(enzyme-linked immunospot,ELIspot)板上.分为正常对照组、阴性对照组(TNF-α抑制剂组)、阳性对照组[脂多糖(lipopolysaccharide,LPS)刺激]、红曲高浓度组(0.5mg/mL)、红曲中浓度组(0.25mg/mL、红曲低浓度组(0.125 mg/mL),细胞种植的同时给予阴性药物、阳性药物和红曲高中低三种浓度药物刺激,24后检测TNF-α分泌情况.结果 红曲高中低浓度组的ELIspot检测,斑点计数均少于正常组,其中红曲高、中浓度组与正常对照组比较差异有统计学意义(P<0.05).结论 ELIspot检测是一种较好的用于观察药物对细胞作用效果的方法;红曲能减少强直性脊柱炎患者外周血单个核细胞TNF-α的分泌. 相似文献
999.
摘 要 目的:研究改变制备工艺后三黄烧伤灵对几种常见细菌的体外抑菌效果。方法: 采用乙醇回流提取、水提取的混合提取新工艺制备三黄烧伤灵。采用微量肉汤稀释法测定改变制备工艺后三黄烧伤灵对大肠埃希菌、铜绿假单胞菌、金黄色葡萄球菌及乙型副伤寒沙门菌的最小抑菌浓度,对新、旧工艺制备三黄烧伤灵的抑菌效果进行比较,并采用纸片法检测抑菌圈。结果: 新工艺制备的三黄烧伤灵对大肠埃希菌、铜绿假单胞菌、金黄色葡萄球菌及乙型副伤寒沙门菌抗菌效果优于旧制备工艺,新工艺的最小抑菌浓度分别为16,16,8,16 μg·mL-1,旧工艺的最小抑菌浓度分别为32,64,16,64 μg·mL-1。结论:改变制备工艺后制得的三黄烧伤灵抗菌效果明显,有一定的临床使用意义。 相似文献
1000.
Henrique Lemos Eslam Mohamed Lei Huang Phillip R. Chandler Rong Ou Rafal Pacholczyk Andrew L. Mellor 《Immunology》2019,158(4):353-361
Reagents that activate the signaling adaptor stimulator of interferon genes (STING) suppress experimentally induced autoimmunity in murine models of multiple sclerosis and arthritis. In this study, we evaluated STING agonists as potential reagents to inhibit spontaneous autoimmune type I diabetes (T1D) onset in non-obese diabetic (NOD) female mice. Treatments with DNA nanoparticles (DNPs), which activate STING when cargo DNA is sensed, delayed T1D onset and reduced T1D incidence when administered before T1D onset. DNP treatment elevated indoleamine 2,3 dioxygenase (IDO) activity, which regulates T-cell immunity, in spleen, pancreatic lymph nodes and pancreas of NOD mice. Therapeutic responses to DNPs were partially reversed by inhibiting IDO and DNP treatment synergized with insulin therapy to further delay T1D onset and reduce T1D incidence. Treating pre-diabetic NOD mice with cyclic guanyl-adenyl dinucleotide (cGAMP) to activate STING directly delayed T1D onset and stimulated interferon-αβ (IFN-αβ), while treatment with cyclic diguanyl nucleotide (cdiGMP) did not delay T1D onset or induce IFN-αβ in NOD mice. DNA sequence analyses revealed that NOD mice possess a STING polymorphism that may explain differential responses to cGAMP and cdiGMP. In summary, STING agonists attenuate T1D progression and DNPs enhance therapeutic responses to insulin therapy. 相似文献