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61.
目的    探讨大黄素-8-O-β-D-吡喃葡萄糖苷对牙龈卟啉单胞菌(P. gingivalis)唾液酸酶活性及其毒力基因表达的影响。方法    使用不同质量浓度的大黄素-8-O-β-D-吡喃葡萄糖苷(0.2、0.5、2、5、10 mg/mL)处理P. gingivalis W83(实验组),用未加药物的P. gingivalis W83作对照(对照组),采用荧光法检测大黄素-8-O-β-D-吡喃葡萄糖苷对P. gingivalis唾液酸酶活性的作用。5 mg/mL大黄素-8-O-β-D-吡喃葡萄糖苷作用于P. gingivalis W83,Real-time PCR法检测毒力基因fimA、fimR、fimS、kgp、rgpA和rgpB的表达情况。结果    大黄素-8-O-β-D-吡喃葡萄糖苷对P. gingivalis唾液酸酶活性产生了抑制作用,当其质量浓度为0.2、0.5、2、5、10 mg/mL时,对唾液酸酶活性的抑制率分别为11.4%、32.23%、40.21%、73.54%、84.31%。与对照组比较,实验组(5 mg/mL大黄素-8-O-β-D-吡喃葡萄糖苷处理)的fimA、fimR、fimS、kgp、rgpA和rgpB基因表达均下降,差异均有统计学意义(均P < 0.05)。结论    大黄素-8-O-β-D-吡喃葡萄糖苷可有效抑制P. gingivalis唾液酸酶活性,其抑制作用会降低细菌毒力基因表达,有望成为预防及治疗牙周炎的新型药物。  相似文献   
62.
随着生活水平及治疗技术的提高,种植修复成为越来越多患者的选择。良好的牙槽嵴和牙龈解剖形态的保存或重建是修复体获得满意美学效果和长期稳定性的先决条件。下前牙是牙周炎的好发牙位,下前牙松动脱落伴随下颌骨的吸收势必会造成软硬组织缺陷。文章完整展示了1例罹患重度牙周病变的下前牙即刻种植、同期引导骨再生结合帐篷式植骨术创造良好硬组织三维条件,获得最终较好种植修复效果的具体实施步骤,积累了针对此类问题的临床经验。  相似文献   
63.
A 22-year-old athlete with nocturnal asymptomatic episodes of transient sinus arrest/sinoatrial block up to 7.3?s and recurrent inappropriate sinus tachycardias which had been incidentally found during Holter electrocardiography diagnostics is presented. In spite of extensive diagnostic work-up including invasive procedures like coronary angiography and electrophysiological study, no causal etiology was found. Based on the normal findings and the lack of symptoms, we decided not to implant a permanent pacemaker. After 14?months, the patient is still asymptomatic. Howerver, the 24-h Holter electrocardiography shows unchanged frequency of nocturnal transient sinus arrest episodes.  相似文献   
64.
目的验证在大鼠节段性骨缺损模型中骨形态发生蛋白结合肽(BMP Binding Peptide,BBP)对于重组人骨形态发生蛋白-2(recombinent human bone morphogenetic protein-2,rhBMP-2)骨诱导作用的影响。方法 70只缺损大鼠分别分成7组,每组不同剂量的rhBMP-2+/-1000 gBBP,4w和8w后分别摄片,动物8w后处死,股骨样本分别手工评估,采用uCT测量骨容积,随后分别采用组织学和生物力学分析。结果高剂量(10 g)rhBMP-2组术后8w可见骨愈合,骨缺损处骨完全覆盖和桥接,但低剂量(5 g和2 g)rhBMP-2组术后8w骨愈合欠佳。与单独应用rhBMP-2相比,使用低剂量的rhBMP-2复合一定量的BBP可以取得更满意的骨形成量。BBP增强rhBMP-2的骨形成活性发生于4~8w时,而在术后早期并无明显作用。单纯应用BBP仅可见骨缺损处局部的钙化,未见骨愈合。结论 BBP能显著增强rhBMP-2的骨形成活性,这种增强作用需要一定时间来产生效果;其活性发生于术后4~8w时,在术后早期并无明显作用。而且BBP本身并没有骨诱导潜力,仅仅能增强rhBMP-2的骨形成活性。BBP起到缓释作用,与rhBMP-2紧密结合后,让rhBMP-2缓慢而持久的释放。  相似文献   
65.
During embryonic development, the lymphatic system emerges by transdifferentiation from the cardinal vein. Although lymphatic and blood vasculature share a close molecular and developmental relationship, they display distinct features and functions. However, even after terminal differentiation, transitions between blood endothelial cells (BEC) and lymphatic endothelial cells (LEC) have been reported. Since phenotypic plasticity and cellular differentiation processes frequently involve epigenetic mechanisms, we hypothesized that DNA methylation might play a role in regulating cell type-specific expression in endothelial cells. By analyzing global gene expression and methylation patterns of primary human dermal LEC and BEC, we identified a highly significant set of genes, which were differentially methylated and expressed. Pathway analyses of the differentially methylated and upregulated genes in LEC revealed involvement in developmental and transdifferentiation processes. We further identified a set of novel genes, which might be implicated in regulating BEC-LEC plasticity and could serve as therapeutic targets and/or biomarkers in vascular diseases associated with alterations in the endothelial phenotype.  相似文献   
66.
Electrocardiographic (ECG) artifacts resulting from misplacements of electrodes are frequent, difficult to detect, and can become of clinical importance. We investigated 2 healthy volunteers and 3 patients with ECG signs of inferior myocardial scars. We exchanged the peripheral electrodes in a defined manner and investigated the resulting ECG for morphology and possible diagnostic errors. In the volunteers, ECG signs of inferior ischemia could be produced. In the patients with ischemic heart disease, normal ECG without signs of ischemia resulted by placing the electrode of the left leg to the left arm. The automatic ECG analyzer was not helpful in detecting artifacts by misplaced electrodes. A very low amplitude of the QRS complex in lead I, II, or III was pathognomonic for electrode misplacement in half of the cases. ECG artifacts must also be suspected when abnormal QRS- or P-axis occur or when QRS morphology does not match with the clinical presentation of the patient.  相似文献   
67.
正乙型肝炎是由乙型肝炎病毒(hepatitis B,HBV)引起的一种严重危害人类健康的疾病,全世界的感染人数超过了24 000万。在美国,妊娠妇女群体中的HBV感染率约为0.7%~0.9%~([1-2])。宫内和围产期垂直传播是全球HBV传播的重要组成部分。研究表明,35%~50%的HBV携带者是由于围产期接触受感染的血液及其污染物而受到感染~([1])。预防受感染孕妇的HBV垂直传播给胎儿,对减少  相似文献   
68.
??Objective??To investigate the clinical features??diagnosis??treatment and prognosis of eosinophilic cystitis in pediatric population. Methods??The records of four patients who had been diagnosed and treated for eosinophilic cystitis from January 2012 to May 2015 in Shengjing Hospital were retrospectively reviewed. Results??All the four patients were boys whose age ranged from 6 to 8 years. The main symptoms of the 4 cases were frequent micturition??odynuria??dysuria??suprapubic pain and hematuria.All of the 4 cases had significant peripheral eosinophilia and increased bladder wall thickness. All of the patients were diagnosed with biopsy. Bladder interstitial eosinophil infiltration was revealed by histopathology. The clinical symptoms??peripheral eosinophilia and bladder imaging changes were relieved after steroids and antihistamines treatment. Three cases developed recurrence. Total course of oral corticosteroids ranged from 3 months to 18 months. One case remained persistent remission for 2 years??two cases had are recurrence and one case had two recurrences. Conclusion??Bladder biopsy is essential to establishing the diagnosis of eosinophilic cystitis. Patients with peripheral eosinophilia and the increased bladder wall thickness should be considered with eosinophilic cystitis. Steroids is effective as medical therapy for eosinophilic cystitis and close long-term follow-up is necessary.  相似文献   
69.
??Objective To investigate the clinical characteristics and treatment of hypereosinophilic syndrome??HES?? in children. Methods The clinical manifestations?? laboratory examinations??gastroscopy and imaging features??pathological results and therapy experience in 13 HES children admitted in Beijing Children’s Hospital??Capital Medical University from January 2009 to February 2016 and related literatures were analyzed retrospectively. Results Of the 13 patients evaluated?? 7 were male??54%?? and 6 were female??46%??. The median age at diagnosis was 9.6 years old??ranging 3 to 14 years old??. The median course of disease was 23 months??ranging 1 to 72 months??. The peripheral eosionophil counts ranged ??4.5—29.2??×109/L??mean 13.5×109/L??. Gastrointestinal tract was the most commonly involved organ?? and was reported in 92%??12/13?? of patients. It was followed in frequency by urinary system??84%????pulmonary??53%????cardiac??23%????and skin??8%?? and liver??8%??. A total of 2 sites were involved in 6 patients??3 sites were involved in 5 patients and 4 sites were involved in 2 patients. Treatment of oral prednisone therapy was given and follow-up of 10 patients had no clinical symptoms??2 patients had stopped prednisone??. But eosionophil counts still increased to varying degrees. Three patients were lost to follow-up. Conclusion HES in children is more common in school age and adolescent children. Gastrointestinal tract??urinary system and pulmonary involvement are more common. Glucocorticoid treatment is effective??which requires to be maintained in small dose in the long term.  相似文献   
70.
摘 要血栓烷A2受体广泛存在于人体不同的组织器官,属于G蛋白偶联受体超家族中的一种七重跨膜蛋白,在血小板膜上也有分布。血栓烷A2受体激活导致一系列连锁反应也是活化血小板的重要途径之一,进而促进止血和血栓形成。目前,抗血小板药物的研究主要集中在血小板活化通路中的受体和信号分子水平,血栓烷A2受体相关的抗血小板药物也受到广泛关注。了解血小板内该受体下的信号转导,对于探讨相关药物作用机制、开发新型或中药有效成分类抗血小板药物具有重要意义。  相似文献   
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