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51.
Siebermair J Pohl T Wakili R Schüssler F Lange P Martens E Beckmann BM Sinner MF Steinbigler P Steinbeck G Kääb S 《Der Internist》2012,53(2):218-222
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
52.
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
53.
Brönneke S Brückner B Peters N Bosch TC Stäb F Wenck H Hagemann S Winnefeld M 《Angiogenesis》2012,15(2):317-329
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
54.
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
55.
������a�������a�����b���š���a���Գɹ�a 《中国实用儿科杂志》2016,31(12):929-932
??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
56.
�ܡ���a��������a��������b��������c������Ρa 《中国实用儿科杂志》2016,31(7):528-532
??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
57.
目的 探讨动态人工智能(AI)超声辅助诊断系统(以下简称动态AI)对甲状腺结节良恶性鉴别诊断价值及对治疗策略的指导意义。方法 选取2021年11月1日至2021年12月31日于中国人民解放军总医院第一医学中心甲状腺(疝)外科接受手术治疗的193例(共346枚结节)甲状腺结节病人,应用动态AI对结节进行良恶性鉴别,对比不同性别、年龄的病人其不同大小、性质的结节的动态AI检查结果、术前细针穿刺细胞学检查结果及术后病理学检查结果,评价动态AI诊断效能。结果 动态AI诊断甲状腺结节的灵敏度为88.5%,特异度为 76.5%,准确率为 85.0%,与术后病理学检查结果有较高一致性(Kappa=0.643,P<0.01)。对比动态AI检查和术前穿刺活检的灵敏度(χ2=0.210,P=0.647)和准确率(χ2=1.699,P=0.192)差异无统计学意义,特异度差异有统计学意义(χ2=7.238,P=0.007)。动态AI检查在不同性别(χ2=0.002,P=0.968)及年龄(χ2=3.913,P=0.41)人群中准确率差异无统计学意义,稳定性较好。良性结节的准确率(76.5%)较恶性结节的准确率(88.5%)低(χ2=8.184,P=0.004)。动态AI检查准确率随着结节大小增加有上升趋势(χ2=7.357,P=0.007),直径>1 cm结节准确率可达94.4%。结论 动态AI检查对甲状腺结节的良恶性有较高的诊断价值,且无创可重复、高效便捷、安全可靠,可减少不必要的穿刺,节约医疗资源及社会成本,可有效辅助外科医师为病人制定科学合理的个体化诊治策略。 相似文献
58.
目的比较腹腔镜辅助保留幽门胃切除术(LAPPG)与腹腔镜辅助远端胃大部切除术(LADG)(BillrothⅠ式吻合)对胃体中部早期胃癌病人术后继发性胆汁反流性胃炎(BRG)的影响。方法自2018年2月至2018年12月,对上海交通大学医学院附属仁济医院胃肠外科收治的69例早期胃体中部癌(cT1N0M0)病人进行1∶1前瞻性随机化入组,其中LAPPG组(行LAPPG)34例,LADG组(行LADG,BillrothⅠ式吻合)35例,进行6个月随访,比较两组术前、术中、术后及随访结果。结果两组病人在年龄、性别、BMI、术前合并症及术后病理诊断的基线水平差异无统计学意义(P>0.05)。两组淋巴结清扫数目、手术时间、术中出血量、术后首次排气时间、胃管拔除时间、Ⅱ级以上并发症差异无统计学意义(P>0.05)。术后6个月随访结果显示,BRG临床表现无特异性,在两组中差异无统计学意义(P>0.05);但内镜下诊断BRG比例LAPPG组显著低于LADG组,差异有统计学意义[3例(8.8%)vs.16例(45.7%),χ^2=11.763,P=0.001];LAPPG组中Kellosalofen分级Ⅱ度以上BRG的比例显著低于LADG组,差异有统计学意义[2例(5.7%)vs.9例(25.7%),χ^2=5.062,P=0.024];组织学活检发现LADG组胃小凹增生1例、腺体萎缩伴肠化3例,LAPPG组未观察到上述病理组织学异常,但两组差异无统计学意义(P>0.05)。结论LAPPG治疗早期胃体中部癌安全可行,该术式较LADG可改善术后BRG的发生率及严重程度。其对病人术后长期疗效及残胃癌发生率的影响仍有待大样本RCT研究的长期随访证实。 相似文献
59.
目的 探讨孤立性髂动脉瘤介入治疗的临床经验。方法 回顾性分析2010年1月至2018年9月昆明医科大学附属延安医院血管介入科采用覆膜支架介入治疗孤立性髂动脉瘤39例,术后3个月、6个月及之后的每年对病人进行随访,探讨相关治疗方法。结果 39例病人分型有1A:Ⅰ型1例,1B:Ⅱ型8例,1D:Ⅳ型17例,2B:Ⅱ型2例,2D:Ⅳ型1例,2E:V型10例。平均瘤体最大直径为(42.4±11.2)mm(23.0~77.0 mm)。39例病人均顺利完成介入手术治疗,技术成功率100%,术中保留双侧髂内动脉1例,保留一侧髂内动脉29例,双侧髂内动脉均封闭9例,术中行一侧髂内动脉栓塞9例,行双侧髂内动脉均栓塞1例,手术时间为(49.0±17.0)min(35.0~87.0 min),术后随访(31.9±17.7)个月(5~69个月),术后除1例左髂动脉瘤破裂且合并肾衰竭的病人死亡,其余病人均好转出院,复查CTA示髂动脉瘤被完全封闭,支架形态位置良好,无内漏及其他并发症。结论 孤立性髂动脉瘤起病隐匿,早期多无症状,CT等检查能够早期诊断。介入治疗是安全有效的方法。应注意在术前根据髂动脉瘤的累及范围,近远端有无足够的锚定区进行分型,并对不同分型进行有差别的个体化治疗。 相似文献
60.
目的 探讨应用皮下负压引流器预防下消化道开腹手术切口愈合不良的价值。方法 回顾性分析2018年10月至2020年1月首都医科大学附属北京友谊医院普外科收治的113例下消化道开放手术病人的临床资料。根据腹壁缝合时是否放置皮下引流器,分为皮下引流组(78例)和对照组(35例)。比较两组病人切口愈合情况,分析切口愈合不良与临床特征的关系以及开放手术切口愈合不良的影响因素。结果 113例病人中,切口愈合不良发生率为14.2%(16/113),其中皮下引流组切口愈合不良发生率为5.1%(4/78),对照组为34.3%(12/35),两组差异具有统计学意义(P<0.05)。多因素分析提示,影响切口愈合不良发生的独立危险因素为未放置皮下引流器(OR=14.510,95%CI 3.411~61.735,P=0.001)、糖尿病(OR=7.064,95%CI 1.286~38.789,P=0.024)及吻合口漏/残端漏(OR=15.004,95%CI 1.876~119.996,P=0.011)。结论 下消化道开放手术切口愈合不良发生率较高,应用皮下负压引流器能有效减少其发生,且操作方便、价格低廉。 相似文献