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991.
肌酸激酶同工酶(Creatine kinase isoenzyme,CK-MB)是早期诊断急性心肌梗死(acute myocardial infarction,AMI)的重要标志物,该研究以荧光微球为标记物研究快速、灵敏的CK-MB荧光免疫层析检测方法。通过N-羟基琥珀酰(NHS)和1-乙基-3-(3-二甲氨基丙基)碳二亚胺盐酸盐(EDC)将荧光微球与市售的抗体共价偶联,优化抗体与荧光微球的偶联条件,对偶联获得的抗体荧光标记物进行表征,制备了CK-MB的荧光免疫层析检测卡,建立了CK-MB荧光免疫层析检测方法。荧光微球偶联率91.7%,CK-MB检测卡定量检测线性范围为1ng/ml~1000ng/ml,灵敏度达到了1ng/ml,CV值8%,回收率84%~108.3%。利用间接ELISA法对市售抗体进行筛选,获得了包被抗体以及标记抗体,建立了心肌损伤标志物肌酸激酶同工酶荧光检测方法,实现血清中CK-MB定性与定量检测,为心肌损伤标志物荧光免疫层析检测方法的研发提供了实验技术基础。 相似文献
992.
邻苯二甲酸二丁酯的毒性作用及机制 总被引:1,自引:0,他引:1
针对环境污染日益严重的现状,探讨了邻苯二甲酸二丁酯(DBP)的肝脏与生殖毒性作用.检测了血浆和肝脏中的关键酶、精子活动力与畸形率,观察了肝脏和睾丸的病理改变.结果表明,DBP可以显著升高谷丙转氨酶(GPT)、谷草转氨酶(GOT)、碱性磷酸酶(AKP)和丙二醛(MDA),显著降低超氧化物歧化酶(SOD)和过氧化氢酶(CAT),表明DBP会诱发小鼠肝脏发生脂质过氧化过程,引起早期的肝脏损伤.DBP能够穿透血-睾屏障,干扰精子的生长和发育过程.因此,DBP是一种对雄性生殖细胞具有潜在诱变危害的遗传毒性化合物. 相似文献
993.
Neuroproteomics in neurotrauma 总被引:4,自引:0,他引:4
Ottens AK Kobeissy FH Golden EC Zhang Z Haskins WE Chen SS Hayes RL Wang KK Denslow ND 《Mass spectrometry reviews》2006,25(3):380-408
Neurotrauma in the form of traumatic brain injury (TBI) afflicts more Americans annually than Alzheimer's and Parkinson's disease combined, yet few researchers have used neuroproteomics to investigate the underlying complex molecular events that exacerbate TBI. Discussed in this review is the methodology needed to explore the neurotrauma proteome-from the types of samples used to the mass spectrometry identification and quantification techniques available. This neuroproteomics survey presents a framework for large-scale protein research in neurotrauma, as applied for immediate TBI biomarker discovery and the far-reaching systems biology understanding of how the brain responds to trauma. Ultimately, knowledge attained through neuroproteomics could lead to clinical diagnostics and therapeutics to lessen the burden of neurotrauma on society. 相似文献
994.
为建立动物脊髓损伤模型,研制了一种新型大鼠脊髓打击器。该装置采用重物自由落体运动原理,采用激光对焦定点打击、步进电机控制调节高度、精密槽型光电传感器检测时间和速度等技术来实现打击棒的定点、定高、定量、一次性打击等打击功能,并可有效避免打击棒的反跳后造成的二次性损伤。实验表明,打击器具有操作简单、可重复性好、精度高等特点,可用来制作不同的动物脊髓损伤模型。 相似文献
995.
996.
混凝土劣化已成为危及构筑物、建筑物安全的一大课题。本文分析了化工厂常见的混凝土劣化的原因,并且给出了反应式,介绍了实例及补强对策。 相似文献
997.
Xianghao Zhan Yiheng Li Yuzhe Liu August G. Domel Hossein Vahid Alizadeh Samuel J. Raymond Jesse Ruan Saeed Barbat Stephen Tiernan Olivier Gevaert Michael M. Zeineh Gerald A. Grant David B. Camarillo 《Journal of the Royal Society Interface》2021,18(179)
Multiple brain injury criteria (BIC) are developed to quickly quantify brain injury risks after head impacts. These BIC originated from different head impact types (e.g. sports and car crashes) are widely used in risk evaluation. However, the accuracy of using the BIC on brain injury risk estimation across head impact types has not been evaluated. Physiologically, brain strain is often considered the key parameter of brain injury. To evaluate the BIC''s risk estimation accuracy across five datasets comprising different head impact types, linear regression was used to model 95% maximum principal strain, 95% maximum principal strain at the corpus callosum and cumulative strain damage (15%) on 18 BIC. The results show significantly different relationships between BIC and brain strain across datasets, indicating the same BIC value may suggest different brain strain across head impact types. The accuracy of brain strain regression is generally decreasing if the BIC regression models are fitted on a dataset with a different type of head impact rather than on the dataset with the same type. Given this finding, this study raises concerns for applying BIC to estimate the brain injury risks for head impacts different from the head impacts on which the BIC was developed. 相似文献
998.
结合工程实例,从结构裂缝现状及裂缝发展情况、地质情况、设计图纸、施工组织情况调查了墙体开裂的原因,分析了地基冻害这一主要原因,并提出了预防冻害的措施和结构补强加固处理的方法。 相似文献
999.
Effect of wheelchair headrest use on pediatric head and neck injury risk outcomes during rear impact
Comparative risks or benefits to wheelchair-seated pediatric occupants in motor vehicles associated with wheelchair headrest use during rear impact were evaluated using pediatric head and neck injury outcome measures. A Hybrid III 6-year-old anthropomorphic test device (ATD), seated in identical WC19-compliant pediatric manual wheelchairs, was used to measure head and neck response during a 25 km/h (16 mph), 11 g rear impact. ATD responses were evaluated across two test scenarios: three sled tests conducted without headrests, and three with slightly modified commercial headrests. Head and neck injury outcomes measures included: linear head acceleration, head injury criteria (HIC) values, neck injury criteria (N(ij)) values, and combined rotational head velocity and acceleration. Neck and head injury outcome measures improved by 34-70% in sled tests conducted with headrests compared to tests without headrests. Headrest use reduced N(ij) values and the likelihood of concussion from values above established injury thresholds to values below injury thresholds. Injury measure outcome reductions suggest lower head and neck injury risks for wheelchair-seated children using wheelchair-mounted headrests as compared to non-headrest users in rear impact. Use of relative comparisons across two test scenarios served to minimize effects of ATD biofidelity limitations. 相似文献
1000.
This study evaluates the performance of different case selection criteria to account for multiple episodes of care when estimating the hospitalisation rate due to road trauma amongst children. The internally linked NSW Inpatient Statistics Collection (ISC) dataset for the period between 1st July, 2000 and 30th June, 2003 was used to identify the "single" episode of care for each hospitalised child motor vehicle passenger residing in NSW. We used two hospitalised injury definitions of a case based on (1) all-diagnoses and (2) principal diagnosis only. We then developed case selection criteria, based on (a) linkage methods only available from linked ISC datasets; (b) selected variables available in both the linked and unlinked ISC datasets, to exclude repeat episodes of care for an injury. Changes in the estimated hospitalisation rate, and sensitivity and specificity, were calculated for each selection criteria compared to the findings from linkage methods as the "gold standard". None of the correction methods for multiple episodes of care was clearly superior in terms of incidence estimation, sensitivity, and specificity concurrently. However, the correction criterion which is optimal may vary depending on different study objectives and different types of hospitalised injuries. 相似文献