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121.
Andrew A. Fulvini Akaash Tuteja Jianhua Le Barbara A. Pokorny Jeanmarie Silverman Doris Bucher 《Vaccine》2021,39(3):545-553
The only effective measure to decrease morbidity and mortality caused by the influenza virus in the human population is worldwide vaccination. Vaccination produces neutralizing antibodies that target the HA1 subunit of the HA (hemagglutinin) protein and are strain specific. The effectiveness of new influenza vaccines are linked to two factors, the correct prediction of the circulating strains in the population in a particular season and the concentration of the HA1 protein in the vaccine formulation. With the advent of the licensing of quadrivalent vaccines, pharmaceutical manufacturers are under considerable pressure due to time constraints and dedicated resources to deliver 194–198 million doses (2020–2021 U.S. market) of vaccine. Considering the valuable resources needed to produce the influenza vaccine in a timely manner, the efficient quantitation of the HA1 protein (the main component in the influenza vaccine) is required. Currently the only method approved by regulatory agencies for quantitation of the HA antigen in vaccines is the single radial immunodiffusion assay (SRID), an antibody dependent assay that is not time efficient. Time efficient methods that are antibody independent e.g. reverse phase-high performance liquid chromatography (RP-HPLC) or size exclusion-HPLC (SE-HPLC) are available. An improved method implementing reverse phase-ultra performance liquid chromatography (RP-UPLC) has been developed to quantitate the HA1 protein antigen present in the high yield reassortant vaccine seed viruses from influenza A H1N1 and H3N2 subtypes harvested from inoculated embryonated chicken eggs. This method differentiates between high yield and lower yielding reassortants in order to select the best vaccine candidate seed virus with the highest growth ‘in ovo’. This direct capability to monitor the HA1 concentration of potential reassortant seed viruses and to choose the best yielding HA influenza reassortant when faced with multiple viral seed candidates provides a major advantage on the industrial scale to the influenza vaccine process. 相似文献
122.
高强度聚焦超声(HIFU)是将超声的能量聚集在很小的区域内,通过高热量灼烧病变组织细胞,但不会对周围其他组织产生影响,因此,其被广泛应用于对肿瘤、大脑疾病和血管疾病的治疗中。现阶段,临床正尝试将磁共振引导的HIFU应用于神经外科手术治疗中,如治疗特发性震颤等。该研究简要回顾了HIFU的原理、设备和临床应用,叙述了其在肝脏、乳腺、前列腺、肾脏、子宫肿瘤治疗中的应用效果及应用前景。 相似文献
123.
目的:探讨雷帕霉素抑制LPS诱导小鼠RAW264.7细胞表达和释放HMGB1的作用机制。方法:传代培养的小鼠RAW264.7细胞分5组接种于6孔板,即仅加培养液的对照组;加250 μg/L LPS的诱导组; 诱导组基础上加100 μg/L雷帕霉素的干预组;干预组基础上加rTNF-α 50 μg/L的抗干预组;及抗干预组基础上加抗鼠TNF-α 100 μg/L的抗体中和组。培养4 h后,ELISA法检测对照组、诱导组和干预组上清液中TNF-α水平;培养24 h后,RT-PCR和Western blotting法分别检测各组细胞内HMGB1 mRNA表达水平和上清液中HMGB1含量。结果:培养4 h,干预组上清液中TNF-α水平与对照组比无显著差异(P>0.05),但明显低于诱导组(P<0.05);培养24 h, 与对照组比,诱导组细胞内HMGB1 mRNA表达明显增强(P<0.05),上清液中HMGB1含量也明显增多(P<0.05);干预组明显减少了HMGB1 mRNA表达及上清液中HMGB1含量(P<0.05); 与干预组比,抗干预组细胞HMGB1 mRNA表达及上清液中HMGB1含量明显增加(P<0.05);抗体中和组细胞HMGB1 mRNA表达水平及上清液中HMGB1含量和干预组无显著差异(P>0.05)。 结论:雷帕霉素抑制LPS诱导RAW264.7细胞表达和释放HMGB1,可能部分地与其抑制TNF-α的表达有关。 相似文献
124.
目的 了解血清涎液化糖链抗原(KL-6)在常见结缔组织病(CTD)并发肺间质病变(ILD)患者中的表达水平及其临床意义。方法 选取2021年4~11月蚌埠医学院第一附属医院收治的187例CTD患者为研究对象,按照结缔组织病有无肺间质病变分为结缔组织病并发肺间质病变(CTD-ILD)组116例,结缔组织病无肺间质病变(CTD-NILD)组71例;选取41例同期本院体检健康者为对照组。在CTD-ILD组中,根据肺高分辨CT(HRCT)表现分为急性组和慢性组;根据HRCT显示的ILD累及范围进行分级(1级,累及范围≤25%;2级,25%<累及范围≤50%;3级,50%<累及范围≤75%;4级,75%<累及范围≤100%);随后根据CTD-ILD患者是否合并有肺部感染分为有肺部感染组和无肺部感染组。采用乳胶凝集法测定血清KL-6水平,比较不同分组血清KL-6水平差异。结果 CTD-ILD组血清KL-6水平高于CTD-NILD组和对照组,差异有统计学意义(P<0.05)。CTD-ILD患者血清KL-6水平在急性组高于慢性组(P<0.05),在有肺部感染组和无肺部感染... 相似文献
125.
Summary The presence, chromatographic properties and localization of neuropeptide Y was demonstrated in postmortem human brain areas of neurologically and neuropsychiatrically normative controls using immunocytochemistry and high performance liquid chromatography combined with radioimmunoassay. NPY-immunoreactivity was found in many regions of the prosencephalon. Numerous perikarya and fibers were present in the neocortex, basal ganglia and limbic-hypothalamic areas. A moderate number of neurons and fibers was observed in the basal forebrain, including the septal complex. A comparative immunohistochemical investigation in perfusion-fixed brains of the old-world ape Saguinus oedipus revealed an almost identical distribution of NPY-immunoreactivity with only minor differences. Colocalization experiments on 1–2 m thin consecutive paraffin sections revealed a large number of NPY neurons throughout the human neostriatum and amygdaloid complex that were also positive for somatostatin. Our findings indicate that detection of neuropeptides in fresh or fixed post-mortem human tissue by different immunochemical methods may actually reflect the in vivo conditions. In addition, the wide distribution of NPY throughout the human brain and its colocalization with other neurotransmitters suggests a physiological role as neuroactive substance, i.e. neuromodulator in the primate central nervous system. 相似文献
126.
John C. Fowler 《Naunyn-Schmiedeberg's archives of pharmacology》1993,347(1):73-78
Summary Concentrations of adenosine and inosine in the incubation media of baths containing rat hippocampal slices were measured during graded hypoxia. Slices were exposed to atmospheres containing 95%, 71%, 48%, 24%, or 0% oxygen, with 5% CO2 and a balance of N2. Absorbance HPLC measurements were made with samples drawn from static tissue baths each containing four slices supported on a net at the interface between the medium and the atmosphere. Concentrations of adenosine and inosine were proportionate to the fractional oxygen content. They were significantly higher in atmospheres of 24% and 0% O2. Introducing a 95% N2/5% O2 atmosphere in place of 95% O2/5% CO2 resulted in a roughly 4-fold increase in the adenosine concentration in the bath. The adenosine transport blocker dipyridamole (200 M), and the convulsant drug picrotoxinin (300 M), had little effect on basal levels of adenosine measured at 95% O2 but significantly augmented the responses seen at 48%, 24% and 0% O2. Picrotoxinin, while increasing the adenosine concentration did not change the ratio of adenosine to inosine. In contrast, dipyridamole significantly increased the ratio of adenosine to inosine. Evoked population spikes were recorded from the CA1 layer. The population spike amplitude was depressed as the fractional oxygen content was reduced. It is concluded that adenosine regulation in the slice preparation is similar to that seen in the intact animal. In particular, the amounts of adenosine released into the incubation medium are related to oxygen availability. 相似文献
127.
128.
探讨了慢性低压低氧对大鼠肺血管反应性的影响 ,以及前列腺素在其中的作用。结果表明 :1离体肺动脉在急性低氧时先收缩后舒张。大鼠经慢性低氧 15 d、 30 d后离体肺动脉对急性低氧所致收缩反应 ( Δ TIH)较各自对照组均明显降低 [(10 .11± 9.5 6 ) mg、 (14.5 7± 10 .0 2 ) m g Vs (2 7.15± 12 .0 9) mg、 (2 7.86± 13.0 7) mg,P<0 .0 1) ];舒张反应 (-Δ TIH)较各自对照组均明显增强 [(14.18± 5 .14) mg、 (2 6 .35± 11.74) m g Vs (9.39± 7.12 ) mg、 (8.99± 7.32 ) mg]。 2慢性低氧 15 d、 30 d后单位重量肺血管对高钾收缩反应 (ΔTK0 )为 [(10 5 .4± 32 .2 ) m g、 (113.9±2 8.3) m g],分别低于各自对照组 [(132 .7± 30 .3) m g、 (133.1± 34 .2 ) mg]。 3消炎痛可增强低氧性肺血管收缩反应 ,慢性低氧 30 d组增强百分比为 (148.87± 5 7.0 8) % ,明显高于其对照组 (5 9.0 2± 2 4.5 2 ) % ,P<0 .0 1。提示 :慢性低氧降低肺血管反应性可能是由于肺血管平滑肌的收缩性降低以及前列腺素对 HPV的调节作用增强所致。 相似文献
129.
目的 :研究人体在高空吸纯氧及缺氧状态下对血清心肌酶及心率的影响。方法 :将实验者分为吸纯氧组和缺氧组及对照组 ,前两组在 5km高空吸纯氧或不吸氧 ,对照组不升空 ,分别测定血清天冬氨酸氨基转移酶 (AST)、乳酸脱氢酶(LDH)、肌酸激酶 (CK)、α 羟丁酸脱氢酶 (α HBCH)和心率变化。结果 :在 5km高空 ,缺氧时CK增高明显 (P <0 .0 5) ,血清心肌酶活性随吸纯氧时间延长有逐渐增高的趋势 ;吸纯氧时血清心肌酶活性随时间延长有逐渐增高的趋势 ,缺氧时心率随缺氧时间延长而逐渐加快。结论 :长时间吸纯氧或缺氧都将对机体产生损害 相似文献
130.
父母养育方式与中学生个性特点及心理健康的相关分析 总被引:13,自引:1,他引:12
目的 探讨父母养育方式对中学生个性及心理健康的影响。方法 采用父母养育方式评价量表(EMBU),艾森克个性问卷(EPQ),心理卫生自评量表(SCL-90),对140名高中一年级学生进行测查。结果:1.父母养育方式与中学生个性特点具有相关性。2.学生的个性特点与自身的心理健康水平密切相关。3.女生的个性与心理健康问题多于男性。结论 父母养育方式与中学生个性的形成和心理健康有密切关系。 相似文献