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上颌第二磨牙近颊融合根中MB2的锥束CT研究   总被引:1,自引:0,他引:1  
陈灏  范兵 《口腔医学研究》2012,28(4):313-315
目的:通过锥束CT技术研究上颌第二磨牙近颊融合根中MB2的发生率。方法:收集199例患者的上颌第二磨牙CBCT数据,观察牙根融合类型、年龄以及牙位对MB2发生的影响。结果:199例患者共有380颗上颌第二磨牙,其中145颗牙的近中颊根与其他牙根融合;近远中颊根融合型(Ⅰ型)和近中颊根腭根融合型(Ⅱ型)的MB2发生率分别是5.5%、41.9%,而全融合型(Ⅲ型)则未发现MB2,Ⅰ、Ⅲ型融合的MB2发生率低于Ⅱ型;随着年龄增大,MB2发生率降低;181例具有双侧上颌第二磨牙的患者中,左右两侧融合根及MB2的发生率无显著差异。结论:上颌第二磨牙近中颊根与其他牙根融合时,其MB2发生率会出现变异。  相似文献   
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A patient’s history of bleeding, whether spontaneous or in response to challenges, provides important information about both the likelihood of that patient having a biochemically-defined hemostatic defect, and that patient’s risk of future bleeding. Other variables including age, comorbidities and medications influence these probabilities. Scoring systems have been devised in an effort to make the estimates quantitative in specific populations. An example of a bleeding score is the MCMDM1-VWD questionnaire, which was developed to predict the likelihood of a patient having von Willebrand disease. It sums standardized details of the bleeding history, weighted by severity. The HAS-BLED score typifies bleeding prediction tools, developed to predict bleeding during anticoagulant therapy. Although prior bleeding is one item in this score, other comorbidities like hypertension or a history of stroke count for more. A third and related concept is that of bleeding case definitions, which are critical to standardize the reporting of outcomes in trials of antithrombotic agents, and which have entrenched the recognition of different severities of bleeding. We advocate that future efforts should blend some of these features. Information about comorbidities and medication use could refine the interpretation of bleeding events in a bleeding score. So could the introduction of a denominator reflecting the number and duration of challenges to which the patient has been exposed when bleeding might have been expected. More detailed information about the type, frequency and severity of prior bleeding could improve the prognostic power of bleeding prediction tools. More detailed history-based scores might ultimately supersede biochemical testing in many cases.  相似文献   
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Of 100 patients (89 men, 11 women) studied preoperatively to determine their aerobic and hemodynamic profiles at rest and during upright treadmill exercise. The mean maximal cardiac output (CO), measured using the direct Fick principle, was 57 ± 14% of average normal values. The reduction in maximal heart rate (63 ± 13% of normal) was a greater factor in the reduction in CO than stroke volume (88 ± 16% of normal). Maximal oxygen consumption (V?O2max) was 48 ± 15% of normal and the greater reduction in V?O22max compared with CO was due to lower peripheral extraction in the coronary patients. Variables that correlated with maximal CO in a univariate analysis included angina severity (r = ?0.45), V?O22max (r = 0.67), maximal heart rate (r = ?0.31), left ventricular dysfunction (r = ?0.45), maximal systolic blood pressure (r = ?0.31) and number of vessels with ≥ 50% diameter reduction (r = ?0.3). Resting ejection fraction did not correlate with maximal CO. In a multivariate analysis, 4 variables correlated significantly (r = 0.77) with maximal CO: in order, V?O22max, number of vessels with ≥ 50% stenosis, magnitude of ST depression and sex.  相似文献   
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AimTo investigate the root and canal morphology of maxillary and mandibular permanent molar teeth in a Caucasian population by using Cone Beam Computed Tomography (CBCT).MethodsA total of 596 permanent molars were included. The number of roots, the number of canals per root and the root canal configurations according to the method of Vertucci were recorded.ResultsAlmost all of maxillary first molars (95.7%) had three separate roots; however, 40.3% of mesiobuccal roots had two canals (MB2). Of 157 maxillary second molars, 88.5% had three roots. Among the mesiobuccal roots, 15.1% had two canals. The majority of mandibular molars (100% of first molars, 89.4% of second molars) had two separate roots. Most distal roots had a simple type I configuration, whereas mesial roots had more complex canal systems, with more than one canal.ConclusionsCBCT is an efficient method of studying root canal systems.  相似文献   
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目的:探讨同型半胱氨酸浓度水平的检测对于早期诊断急性心肌梗死的应用价值。方法选择2013年1月~2013年12月确诊为冠心病的患者53例为试验组,选择同期进行体检且结果显示为健康的50例为对照组,试验组和对照组均进行同型半胱氨酸、肌酸激酶、肌酸激酶同工酶的测定,对结果进行综合分析。结果试验组的患者血清同型半胱氨酸、肌酸激酶、肌酸激酶同工酶的浓度水平较对照组均有明显上升趋势,差异有统计学意义(P<0.05);阳性检出率分析,试验组患者的的同型半胱氨酸、肌酸激酶和肌酸激酶同工酶的检测结果阳性率分别为84.91%(45/53)、81.13%(43/53)、83.02%(44/53),同型半胱氨酸检测结果阳性率分别与肌酸激酶、肌酸激酶同工酶两两比较,差异无统计学意义(P>0.05);临床标本相关性分析,同型半胱氨酸检测结果和临床诊断结果的相关性好,Kappa值等于0.81。结论同型半胱氨酸是一种辅助诊断冠心病的有效指标,具有较好的灵敏度和临床符合性。  相似文献   
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A study of 102 patients consecutively admitted to a coronary care unit (CCU) investigated the clinical usefulness of three different immunoenzymometrical CKMB methods: NovoClone CK-MB, ICON QSR CKMB and IMx CK-MB. Blood samples were drawn on admission and then every 6 h for 48 h. The three different methods correlated very well (r = 0.93-0.96). With discrimination levels of 10 micrograms.l-1 for NovoClone CK-MB and 5 micrograms.l-1 for the other two methods, a sensitivity of 1.0 and a still acceptable specificity (> 0.81) were achieved. In the group of patients (n = 53) with suspicion of acute myocardial infarction (AMI) but with no standard criteria for AMI, 14 patients were identified with small but significant increase of serum CKMB (mass concentration) and an increased CKMB (mass concentration)/CK ratio. During a 4 year follow-up nine out of these 14 patients died within 2 years, the majority being coronary deaths, as compared to only two out of the remaining 39 non-AMI patients with suspicion of AMI but with normal CKMB values (chi 2 = 18.47, P < 0.001). The finding of such a high mortality rate among patients with increased CKMB (mass concentration) has an important prognostic value even in patients without standard criteria for AMI.  相似文献   
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