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1.
目的 :观察冠心病患者潘生丁试验 (DP- ECG)及潘生丁食管心房调搏复合试验 (TRAS- DP- ECG)前、后心电图 ST段、校正 QT间期 (QTc)及 QT间期离散度 (QTd)的变化 ,以评价 TRAS- DP- ECG诊断冠心病的价值。方法 :对 5 0例冠心病 (CHD)患者 (CHD组 )及 30例正常者 (对照组 )进行 DP- ECG和 TRAS- DP- ECG,记录试验前后 12导联同步心电图 ,测量其 ST段 ,QTc及 QTd。根据分布曲线求出 QTc及 QTd的截断点。分别计算两种试验的敏感度、特异度及准确度。结果 :如以 QTd≥ 40 m s为截断点 ,以 DP- ECG诊断 CHD时 ,其敏感度、特异度、准确度分别为 76 % ,93% ,82 % ;以 TRAS- DP- ECG诊断 CHD时 ,其敏感度、特异度、准确度分别为 92 % ,93% ,92 %。结论 :TRAS- DP- ECG时 ,如以 QTd≥ 40 m s为截断点 ,可明显提高其诊断的敏感度及准确度而不影响其特异度。 QTd≥40 m s可作为 TRAS- DP- ECG时诊断 CHD的一项重要参考指标  相似文献   

2.
目的 :评价食道心房超速负荷试验的 QT间期离散度 (QTd)诊断冠心病的价值。方法 :对 32例冠心病患者 (冠心病组 )及 34例正常者 (对照组 )进行食道心房超速负荷试验 ,记录试验前后 12导联同步心电图 ,测量其 ST段、校正 QT间期 (QTc)及 QTd。根据 ROC曲线求出 QTc及 QTd的截断点 ,以冠脉造影为诊断冠心病的标准诊断方法 ,利用四格表法 ,分别计算各观测指标的特异度及敏感度。并与“并联试验”相互比较。结果 :ST段下移、QTc,QTd诊断冠心病的特异度分别为 10 0 % ,6 8% ,94% ;敏感度分别为 5 3% ,78%和 84%。 ST段下移和 QTd并联试验时敏感度可达 94%。结论 :食道心房超速负荷试验时 ,如以传统的诊断指标 ST段下移 ,结合 QTd,可明显提高其诊断的敏感度 ,可作一项重要参考指标  相似文献   

3.
潘生丁试验中QT间期离散度增加对冠心病诊断价值的探讨   总被引:3,自引:0,他引:3  
目的观察冠心病患者潘生丁试验前后心电图ST段、校正QT间期(QTc)及QT间期离散度(QTd)的变化,以探讨潘生丁试验时诊断冠心病的更敏感及特异的指标。方法对30例冠心病患者(冠心病组)及32例正常者(对照组)进行潘生丁试验,记录试验前后12导联同步心电图,测量其ST段,QTc及QTd的改变。根据受试者作业特征曲线(ROC曲线)求出QTc及QTd的阳性分界点,结合传统诊断标准ST段下移≥0.1mV,分别计算其特异性及敏感性。并与“并联诊断”方法进行比较。结果以潘生丁试验诊断冠心病时,如分别以ST段下移≥0.1mv、QTc≥440ms、QTd≥40ms为标准,其特异性分别为100%、68.8%、93.8%;敏感性分别为53.3%、83.3%和87.6%。如采用“并联诊断”方法,分别以ST段下移≥0.1mV和QTc≥440ms、ST段下移≥0.1mV和QTd≥40ms、QTc≥440ms和QTd≥40ms为标准,其特异性分别为68.8%、93.8%、68.8%。敏感性分别为70.0%、96.8%、90.0%。结论在潘生丁试验时,如以传统的诊断标准(ST段下移≥0.1mV),结合QTd≥40ms,可明显提高其诊断的敏感性而不影响其特异性,QTd≥40ms可作为潘生丁试验时诊断冠心病的一项重要参考指标。  相似文献   

4.
目的探讨QTc间期、QTd、Tp-ec间期、Tp-ed、Tp-e/QT比值对室性期前收缩患者复极储备功能的评价作用。方法入选窦性心律合并室性期前收缩患者229例,根据室性期前收缩后窦性心动周期中QT间期的恢复,将恢复异常者纳入观察组,将恢复正常者纳入对照组,比较组间QTc间期、QTd、Tp-ec间期、Tp-ed、室速发作的差异性;比较组内不同心率下QTc间期的变化;评价QTc间期、QTd、Tp-ec间期、Tp-ed、Tp-e/QT比值对室性期前收缩患者心室复极异常的诊断价值。结果观察组与对照组间性别、年龄、QTd无统计学差异,QTc间期(p=0.0100.05)、Tp-ec间期(p=0.0000.05)、Tp-ed(p=0.030.05)有统计学差异,室速发作(17例、5例),发生率(p=0.0030.05)有统计学差异;观察组、对照组不同心率下QTc间期变化有统计学差异;QTc、Tp-ec、Tp-e/QT比值对复极异常有诊断价值(p0.05),QTd、TP-ed、对复极异常无诊断价值(p0.05),各指标诊断复极储备异常的最佳界值如下:男性QTc≥458ms,女性QTc≥469ms,Tp-ec≥95ms,TP-e/QT比值≥0.22。结论 QTc、QTd、TP-e、TP-ed、TP-e/QT比值是适用于评价室性期前收缩患者心室复极储备功能异常的无创性指标,结合室性期前收缩后QT间期的动态性变化可提高诊断的准确度。对SCD高危人群的早期诊断及预防性治疗有指导作用。  相似文献   

5.
目的通过平板运动试验(ETT)前后冠心病(CHD)病人与冠状动脉正常者的QT离散度(QTd)变化,研究运动引起的心肌缺血对QTd的影响。方法分析经冠状动脉造影(CAG)证实的41例CHD病人与45例CAG正常者ETT前和运动高峰时体表十二导联心电图QTd变化。结果运动前、运动高峰CHD组QTd分别为(47.84±11.19)ms、(62.16±10.45)ms(P0.01);而CAG正常者分别为(24.22±15.15)ms、(23.11±14.43)ms(P0.05)。以运动中QT≥50ms判为异常,诊断CHD的敏感性为86.2%,特异性88.9%,预测准确性87.5%。结论运动高峰较大的QTd有助于反映冠状动脉病变及心肌缺血程度。并提示QTd是ETT中诊断CHD心肌缺血敏感而特异的指标。  相似文献   

6.
目的探讨急诊经皮冠状动脉介入治疗(PCI)后对QT间期离散度(QTd)的影响。方法对70例ST段抬高的急性心肌梗死(AMI)患者行急诊PCI前和PCI后24h内12导联同步心电图QT间期、校正QT间期(QTc)、QTd及校正QT间期离散度(QTcd)4项指标进行对比分析。并监测严重心律失常发生情况。结果PCI后QT和QTc与术前差异无显著性,而QTd和QTcd则较术前明显减少,差异有显著性意义(P<0.01)。28例术前有恶性心律失常,其QTd明显高于无心律失常的患者[(70±18)msvs(52±15)ms,P<0.01];术后QTd降至(45±16)ms(P<0.01),室性心律失常消失或减少。结论急诊PCI能显著减少AMI患者的QTd和QTcd,降低急性期恶性心律失常的发生。  相似文献   

7.
目的 研究经食道心房调搏后QT离散度的变化在诊断冠心病的中价值.方法 按世界卫生组织冠心病的诊断标准,选取住院患者58人做为观察对象,同期选取健康人30人做为对照组,两组均经食道心房调搏心脏负荷试验,当达到负荷心率或出现心绞痛,ST段下移≥0.1mv,停止试验,并于调搏前和调搏后做同步12导联体表心电图,走纸速度为50mm/s,并测量其QT离散度.结果 观察组调搏前后QT离散度有明显变化(P<0.01),而对照组变化不明显(P>0.01),如以QTd≥60ms做为临界值诊断冠心病,其敏感性为89.6%,特异性为93.3%.结论 以QTd≥60ms做为标准,经食道心房调搏诊断冠心病是一可靠的指标.  相似文献   

8.
目的 :比较体表电位标测 (BSPM)、心电图 (ECG)和高频心电图 (HFECG)三种心电方法对冠心病 (CHD)的诊断价值。方法 :使用 BSPM- 型体表电位标测微机系统 ,对冠脉造影确诊的 60例 CHD患者和 60例正常人进行BSPM,并分析 T峰值图图形和极小值位置的变化。同时记录 ECG和 HFECG,并由专业人员盲法分析其变化 ,评价三种方法的诊断价值。结果 :ECG,HFECG和 BSPM诊断的敏感度分别为 67% ,87%和 85 % ,特异度分别为63% ,75 %和 90 % ,准确度分别为 65 % ,81%和 88%。诊断的敏感度 HFECG和 BSPM均显著高于 ECG(P<0 .0 5 ) ,特异度 HFECG与 ECG无差别 (P>0 .0 5 ) ,而 BSPM非常显著高于 ECG(P<0 .0 1) ,也显著高于 HFECG(P<0 .0 5 )。结论 :ECG诊断 CHD的敏感度和特异度都较低 ,HFECG能提高敏感度 ,而 BSPM既能提高敏感度 ,又能提高特异度 ,BSPM是一种价值较高的 CHD诊断方法。  相似文献   

9.
平板运动试验QTd、QTcd、JTd对老年冠心病的诊断价值   总被引:1,自引:0,他引:1  
QT离散度(QTd)预测严重室性心律失常和心源性猝死的价值已得到公认。文献报道冠心病患者QTd明显增大。近年来,QTc(用心率校正的QT间期)延长及QTd增大的临床意义不断受到重视。但对于老年冠心病患者报道较少。本文通过对38例明确诊断冠心病的老年患者行运动试验,对比其运动前后的QTd、QTc、JTd的变化,以比较其对冠心病的诊断价值。  相似文献   

10.
目的 探讨糖尿病并发冠心病病人的QT间期(QTc)与QT离散度(QTcd)。方法 60例2型糖尿病病人采用ECG——9130P同步12导联心电图机,用Bazett公式计算QTd、QTcd。按是否并发心血管病分为糖1组(无并发症组)与糖2组(并发心血管病组)。结果 糖1组除QT低于对照组(P〈0.05)外,QTc、QTd、QTcd与对照组比较无统计学意义。糖2组与糖1组比较QT、QTc、QTd、QTcd均有统计学意义(P〈0.05或P〈0.01)。结论 糖尿病并发冠心病易造成严重心肌缺血、恶性心律失常和猝死。  相似文献   

11.
Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.  相似文献   

12.
The immunoneuroendocrine role of melatonin   总被引:19,自引:0,他引:19  
Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.  相似文献   

13.
Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm2) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.  相似文献   

14.
Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.  相似文献   

15.
16.
17.
Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.  相似文献   

18.
Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.  相似文献   

19.
Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.  相似文献   

20.
《Indian heart journal》2016,68(4):450-463
The knowledge of variety of chronic total occlusion (CTO) hardware and the ability to use them represents the key to success of any CTO interventions. However, the multiplicity of CTO hardware and their physical character and the terminology used by experts create confusion in the mind of an average interventional cardiologist, particularly a beginner in this field. This knowledge is available but is scattered. We aim to classify and compare the currently used devices based on their properties focusing on how physical character of each device can be utilized in a specific situation, thus clarifying and simplifying the technical discourse.  相似文献   

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