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51.
目的 研究血管内皮生长因子(VEGF)对缺血/再灌注损伤胰腺组织细胞凋亡的影响.方法 将雄性sD大鼠30只随机分为3组(n=10),A组为假手术组,B组为缺血/再灌注损伤组,C组为缺血/再灌注损伤+VEGF反义寡核苷酸组.通过血管夹阻断大鼠腹腔干及肠系膜上动脉30 min,然后去除血管夹再灌注6 h,建立大鼠胰腺缺血/再灌注损伤模型.对各组胰腺组织进行VEGF免疫组化染色及TUNEL法细胞凋亡检测.结果 缺血/再灌注损伤后胰腺组织出现细胞凋亡,同时VEGF蛋白表达上调.缺血/再灌注损伤+VEGF反义寡核苷酸组的胰腺组织VEGF蛋白表达较缺血/再灌注损伤组显著减少(P<0.05),前者细胞凋亡指数较后者明显升高(P<0.05).结论 VEGF能抑制缺血/再灌注损伤胰腺细胞凋亡,可能对胰腺缺血再灌注损伤具有保护作用. 相似文献
52.
目的 白细胞介素 1 3(IL 1 3)是新近发现的一种抗炎性细胞因子 ,其在肾小球肾炎中的作用尚不清楚 ,该研究探讨脂多糖 (LPS)对体外培养的人肾小球系膜细胞 (HMC)表达IL 1 3作用以及IL 1 3对HMC促炎性细胞因子、趋化因子和促纤维化因子基因表达的影响。方法 体外培养HMC ,加入不同浓度的LPS和 (或 )IL 1 3后 ,用逆转录 -聚合酶链反应和ELISA检测HMCIL 1 3mRNA表达和细胞培养上清液中IL 1 3蛋白含量 ;应用核酸酶保护法检测HMC肿瘤坏死因子 α(TNF α)、白介素 - 1α(IL 1α)、白介素 - 1 β(IL 1 β)、单核细胞趋化蛋白 1(MCP 1 )、白介素 8(IL 8)、转化生长因子 - β1 (TGF β1 )mRNA的表达。 结果 未予LPS刺激的HMC不表达IL 1 3mRNA和蛋白 ;LPS呈剂量依赖性和时间依赖性诱导HMC表达IL 1 3mRNA和分泌IL 1 3蛋白。HMC受LPS刺激后 1 2h即可表达IL 1 3mRNA ,4 8h达高峰 ,72h仍维持在较高的水平。HMC受LPS刺激后 2 4h ,其培养上清液中检测到IL 1 3蛋白 ,4 8h和 72h进一步增加。外源性IL 1 3呈剂量依赖性地抑制LPS诱导的系膜细胞TNF α ,IL 1α ,IL 1 β ,MCP 1 ,IL 8,TGF β1mRNA的表达。应用抗IL 1 3抗体中和内源性IL 1 3后 ,上述炎症因子表达增强。结论 IL 1 3是HMC自分泌因子。IL 1 3可抑制LPS诱导 相似文献
53.
Objective. To report the sign of ”spinolaminar breach” and its likely importance in fractures of the cervical spinous processes.
Design. Six cases of spinous process fractures demonstrating disruption of the spinolaminar line or ”spinolaminar breach” were analyzed.
Lateral and anteroposterior radiographs (n=6), CT scans (n=3) and MRI scans (n=1) were reviewed together by the authors, with consensus being reached as to the radiographic findings. Clinical records
were also reviewed.
Results. The levels of injury were C6 (n=5) and C5 (n=2). Injuries were associated with delayed anterior subluxation (n=4) and neurological deficit (n=2). Five patients were male and one was female with a mean age of 31 years (range 8–59 years). Injuries resulted from motor
vehicle accidents (n=4), a motor cycle accident (n=1) and a fall (n=1).
Conclusion. ”Spinolaminar breach”, or disruption of the spinolaminar line, indicates a complex spinous process fracture with extension
into the lamina and spinal canal. Spinous process fractures with spinolaminar breach may have associated posterior ligamentous
injury with potential for delayed instability and neurological deficit. It is important that radiologists and physicians caring
for the trauma patient be aware of this sign in order to avoid misdiagnosis as a ”clay shoveler’s fracture”, which can lead
to adverse outcome.
Received: 20 July 1999 Revision requested: 14 September 1999 Revision received: 13 October 1999 Accepted: 26 October 1999 相似文献
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56.
Lorna M Gibson Martha F Hanby Sarah M Al-Bachari Laura M Parkes Stuart M Allan Hedley CA Emsley 《Journal of cerebral blood flow and metabolism》2014,34(4):564-570
The interface between cerebrovascular disease (CVD) and epilepsy is complex and multifaceted. Late-onset epilepsy (LOE) is increasingly common and is often attributed to CVD, and is indeed associated with an increased risk of stroke. This relationship is easily recognizable where there is a history of stroke, particularly involving the cerebral cortex. However, the relationship with otherwise occult, subcortical CVD is currently less well established yet causality is often invoked. In this review, we consider the diagnosis of LOE in clinical practice—including its behaviour as a potential mimic of acute ischemic stroke and transient ischemic attack; evidence for an association between occult CVD and LOE; and potential mechanisms of epileptogenesis in occult CVD, including potential interrelationships between disordered cerebral metabolism and perfusion, disrupted neurovascular unit integrity, blood–brain barrier dysfunction, and inflammation. We also discuss recently recognized issues concerning antiepileptic drug treatment and vascular risk and consider a variety of less common CVD entities associated with seizures. 相似文献
57.
58.
M. Knösel W. Engelke H.‐J. Helms A. Bleckmann 《European journal of dental education》2012,16(3):131-137
Objective: To systematically assess the informational value, quality, intention, source and bias of web 2.0 footage whose aim is peer‐to‐peer education about oral implantology. Methods: YouTube ( http://www.youtube.com ) was scanned on 15 October 2010 for oral implantology‐related videos using an adequately pre‐defined search query. Search results were filtered with the system‐generated category ‘education’ and the additional criterion ‘most viewed’. Only those videos with at least 1000 views were included (total 124, of which 27 were excluded because they were not related to implantology). Filtered videos were discussed and rated with particular regard to the educational needs of potential groups of addressees [(i) undergraduates and laymen, (ii) dentists without or currently undergoing a specialisation in oral implantology and (iii) dentists who have completed a specialisation in the field of oral implantology] by a jury consisting of (i) an accredited post‐graduate university instructor with 22 years of professional teaching experience in the field of implantology, (ii) a university lecturer in dentistry/orthodontics with 10 years teaching experience and (iii) a university haematologist/oncologist. They were required to fill out a questionnaire for each video. The data were statistically analysed using non‐parametric ANOVA (α = 5%) and a sign test (α = 0.05/3 = 0.017). Results: The YouTube scan produced 1710 results in the category ‘EDU’. The analysis revealed that there is a wide range of instructional footage on this topic, but with highly variable range in quality and informational value. Footage intention was to large proportions (47.4%) a mixture of education and advertisement. Its usefulness differed significantly for the three groups of addressees, offering greater novelty to undergraduates and post‐graduates. Conclusion: YouTube and similar social media websites may have a potential capacity and value in complementing continuing education in the technique of oral implantology. As a means of achieving an acceptable level of knowledge about the topic when used alone, it should not be considered to be suitable at this point in time. 相似文献
59.
Biologic basis for interleukin-1 in disease 总被引:164,自引:6,他引:164
To understand the role of the proinflammatory cytokine interleukin-1 (IL-1) in disease, investigators have studied how production of the different members of the IL-1 family is controlled, the various biologic activities of IL-1, the distinct and various functions of the IL-1 receptor (IL-1R) family, and the complexity of intracellular signaling. Mice deficient in IL-1Beta, IL-1Beta converting enzyme, and IL-1R type I have also been studied. Humans have been injected with IL- 1 (either IL-1alpha or IL-1beta) for enhancing bone marrow recovery and for cancer treatment. The IL-1-specific receptor antagonist (IL-1Ra) has also been tested in clinical trials. The topics discussed in this review include production and activities of IL-1 and IL-1Ra molecules, the effects of IL-1 on gene expression, functions of cell-bound and soluble IL-1 receptors, the importance of the IL-1R accessory protein, newly discovered signal transduction pathways, naturally occurring cytokines limiting IL-1 production or activity, the effects of blocking cyclooxygenase and nitric oxide, and the outcomes of IL-1 and IL-1 Ra in human trials. Special attention is paid to IL-1beta converting enzyme and programmed cell death. The roles of IL-1 in hematopoiesis, leukemia, atherosclerosis, and growth of solid tumors are also discussed. This is a lengthy review, with 586 citations chosen to illustrate specific areas of interest rather than a compendium of references. At the end of each section, a short commentary summarizes what the author considers established or controversial topics linking the biology of IL-1 to mechanisms of disease. 相似文献
60.