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1.
目的:研究血清胱抑素C水平与糖尿病心室重构的关系。方法:选择2013年10月~2015年10月在我院进行诊治的糖尿病患者90例,检测血清胱抑素C水平,按照糖尿病患者血清胱抑素C水平的中位数,分为正常组(胱抑素C水平1.65mg/L)和升高组(胱抑素C水平1.65mg/L)。行超声心动图检测左室舒张末内径、左房内径、左室舒张末容积、室间隔厚度和左室后壁厚度,并计算出左室质量指数。对两组的这些指标进行比较,并分析血清胱抑素C与糖尿病心室重构的相关性。结果:与正常组相比,升高组的胱抑素C、左室舒张末内径、左房内径、室间隔厚度、左室后壁厚度、左室质量指数和脑钠肽水平均明显增高(P0.05);经过相关性分析,血清胱抑素C水平与左室舒张末内径、左房内径、室间隔厚度、左室后壁厚度、左室质量指数和脑钠肽均呈正相关(P0.05);Logistic回归分析显示左室舒张末内径、左房内径、室间隔厚度、左室后壁厚度、左室质量指数和脑钠肽等是胱抑素C水平升高的危险因素。结论:血清胱抑素C水平与糖尿病患者的心功能和心室重构具有明显相关性,可作为衡量糖尿病患者心室重构程度的一项参考指标。  相似文献   

2.
Assessment of left ventricular function in five patients with chronic postinfarction left ventricular aneurysm was carried out at the time of left heart catheterization and compared with that in six normal subjects. One patient was investigated before and after surgical resection of the aneurysm. The presence of the aneurysm placed the left ventricle at a mechanical disadvantage in systole and increased the resistance to diastolic filling (impedance). This was true even in patients with normal cardiac indices who were not badly disabled. Resection of the aneurysm corrected both these abnormalities, and, as well, lowered the time-tension index at a time when calculated left ventricular work was much increased. These differences between normals and patients with aneurysms, and the changes occurring as a result of resection of an aneurysm, show that the presence of the aneurysm places the left ventricle at a mechanical disadvantage in systole as well as altering its diastolic filling characteristics.  相似文献   

3.
The present study evaluates the participation of the vagus nerve in pre-pubertal rats with unilateral ovariectomy on puberty onset, and on progesterone, testosterone and estradiol serum levels, and the compensatory responses of the ovary. Unilateral vagotomy did not modify the onset of puberty in unilaterally ovariectomized rats. Ovulation rates of animals with the left vagus nerve sectioned and the left ovary in-situ was lower than in rats with only unilateral ovariectomy. Sectioning the left vagus to 32-day old rats with the left ovary in-situ resulted in lower compensatory ovarian hypertrophy than in rats with right unilateral ovariectomy. Twenty-eight or 32-day old animals with sectioning of the right vagus nerve and the right ovary in situ showed higher compensatory ovulation. Twenty-eight -day old rats with the right ovary in situ had higher progesterone and testosterone levels than animals of the same age with the left ovary in-situ. Compared to animals with the right ovary in situ, animals treated at 32-days of age, sectioning the ipsi-lateral vagus nerve resulted in higher progesterone levels. Higher progesterone levels were observed in 28- and 32 days old rats with the left ovary in situ and left vagus nerve sectioned. Thirty-two day old animals with the right ovary in situ and right vagus nerve sectioned had higher progesterone levels than rats of the same age with the left ovary in situ and left vagus nerve sectioned. Left vagotomy to 28-day old rats with the left ovary in situ resulted in higher testosterone levels, a reverse response to that observed in animals with sectioning of the right vagus and the right ovary in situ. Thirty-two day old rats with the left ovary in situ and left vagus nerve sectioned showed lower testosterone levels than animals without vagotomy and with the left ovary in situ.  相似文献   

4.
A 21-year-old woman presented with congestive heart failure caused by congenital mitral and tricuspid insufficiency, associated with great left atrium enlargement. Transthoracic echocardiogram revealed heart dextroversion associated with mitral and tricuspid severe insufficiency and left atrium enlargement (14 cm), confirmed by magnetic resonance study. The left atrium was reduced by a tangential triangular resection of the posterior wall, between the pulmonary veins, suturing the edges of the left atrium with bovine pericardium strip reinforcement. Mitral and tricuspid valves were repaired. The postoperative course was uneventful, and the patient was discharged in the 15th postoperative day. A control magnetic resonance study revealed a 50% reduction in left atrium size. Evolution of left atrium resection is excellent, with low recurrence of arrhythmias, embolism, or heart failure.  相似文献   

5.
6.
During a full cardiac cycle, the left atrium successively behaves as a reservoir, a conduit and a pump. This complex behavior makes it unrealistic to apply the time-varying elastance theory to characterize the left atrium, first, because this theory has known limitations, and second, because it is still uncertain whether the load independence hypothesis holds. In this study, we aim to bypass this uncertainty by relying on another kind of mathematical model of the cardiac chambers. In the present work, we describe both the left atrium and the left ventricle with a multi-scale model. The multi-scale property of this model comes from the fact that pressure inside a cardiac chamber is derived from a model of the sarcomere behavior. Macroscopic model parameters are identified from reference dog hemodynamic data. The multi-scale model of the cardiovascular system including the left atrium is then simulated to show that the physiological roles of the left atrium are correctly reproduced. This include a biphasic pressure wave and an eight-shaped pressure-volume loop. We also test the validity of our model in non basal conditions by reproducing a preload reduction experiment by inferior vena cava occlusion with the model. We compute the variation of eight indices before and after this experiment and obtain the same variation as experimentally observed for seven out of the eight indices. In summary, the multi-scale mathematical model presented in this work is able to correctly account for the three roles of the left atrium and also exhibits a realistic left atrial pressure-volume loop. Furthermore, the model has been previously presented and validated for the left ventricle. This makes it a proper alternative to the time-varying elastance theory if the focus is set on precisely representing the left atrial and left ventricular behaviors.  相似文献   

7.
8.
In order to study left ventricular hypertrophy patterns in obese hypertensives, we examined 132 patients with essential hypertension by 2D, M-mode and Doppler echocardiography. The patients were classified in four comparable groups, corresponding to the values of Quetelet's body mass index (BMI) and grades of obesity. More obese hypertensives had on average larger left ventricles with thicker walls and larger left atria than less obese, or lean ones. Left ventricular mass increased significantly and progressively with advancing grades of obesity, but relative wall thickness (wall thickness/cavity size ratio) did not diminish. Doppler echocardiography revealed significantly higher prevalence of left ventricular diastolic dysfunction among obese than among lean hypertensives. In the second part of our study, we analyzed the subgroups defined by the severity of hypertension and the age of the patients. The correlation of the indices of left ventricular and left atrial hypertrophy with the BMI values was considerably better in the group of moderate than in the group of mild hypertension. The r values were 0.62 vs. 0.22 for left ventricular mass and 0.64 vs. 0.26 for left atrial dimension. The group of patients with severe hypertension was characterized by left ventricular cavity enlargement in correlation with increasing BMI values, but without corresponding left ventricular wall thickening. So called left ventricular "eccentricity index", as the reverse value of relative wall thickness, correlated well (r = 0.76) with the BMI values. The indices of left ventricular hypertrophy correlated with the BMI values slightly better in middle age groups than in the groups of the youngest (< or = 30 years) or the eldest (> or = 61 years) hypertensives. In conclusion, eccentric left ventricular hypertrophy does not seem to be a distinctive feature of hypertensive heart disease in obesity. There is only some tendency toward the "eccentricity" of left ventricular geometry which becomes more apparent in more severe forms of hypertension, especially in very obese persons.  相似文献   

9.
Anomalous origin of the left coronary artery from the pulmonary artery was diagnosed in an infant girl who had evidence of transmural myocardial infarction of the free wall of the left ventricle. At age 13 months, she underwent a palliative left Vineberg implant, and remained asymptomatic until she was 8 years of age. At that time, she underwent suturing of the left coronary ostium for obliteration of the left coronary shunt at the pulmonary artery. At age 13, she underwent aortocoronary bypass to the left main coronary artery, with end-to-end anastomosis. The patient remains asymptomatic to date. We believe that this is the first reported case of a Vineberg operation performed in an infant for palliation of an anomalous left coronary artery originating from the pulmonary artery. This method allows time for the development of collateral circulation to the left coronary artery before definitive surgery is performed.  相似文献   

10.
Unnatural dynamics of the notorious vortex in the left ventricle is often associated with cardiac disease. Understanding how different cardiac diseases alter the flow physics in the left ventricle may therefore provide a powerful tool for disease detection. In this work, the fluid dynamics in the left ventricle subject to different severities of aortic regurgitation is experimentally investigated by performing time-resolved particle image velocimetry in a left heart duplicator. Diastolic vortex reversal was observed in the left ventricle accompanied by an increase in viscous energy dissipation. Vortex dynamics and energy dissipation may provide useful insights on sub-optimal flow patterns in the left ventricle.  相似文献   

11.
本文研究了在保留最大化内在功能连接条件下抑郁症患者脑网络效率的改变,并探索了改变的拓扑效率和抑郁症病理学之间的关系.为此,我们收集了20例抑郁症患者和20例在年龄、性别和教育水平相匹配的健康被试的静息态功能磁共振图像数据.图论分析显示,与健康对照组比较,抑郁症患者的节点效率减少在左海马旁回、右杏仁核,左颞横回和左颞极(颞中回)减少.减少的节点效率表明,在抑郁症患者脑网络中这些区域传送信息到其他区域的能力减弱.此外,发现局部效率降低在左内侧额上回、左眶部额上回、右回直肌、左杏仁核、右顶上回、左丘脑和左颞极(颞中回).并且发现左内侧额上回、左杏仁核、左丘脑与PHQ-9得分呈负相关.降低的局部效率表明抑郁症患者脑网络中这些区域的局部网络信息传送能力受到抑制.这些结果进一步确认在抑郁症患者中涉及情感信息处理的前额-丘脑-边缘区域被破坏.我们的发现为抑郁症病人的辅助诊断提供了新的潜在生物学标记物.  相似文献   

12.
Seventy heart preparations of persons belonging to different sex and age have been investigated, using a complex of anatomical and histological techniques. The dimensions of the sinoatrial node (SAN) vary with age and depend on various size and form of the heart. The large atrial branch of the right and left coronary arteries supplies mainly the SAN with blood. More seldom the atrial branches of both cardiac arteries, having anastomoses, realize the SAN blood supply. The character of the SAN vascularization depends on branching variations of the atrial vessels. At the right coronary variant the sources of the SAN blood supply are the SAN branch, the right intermediate or right posterior atrial branches, and at the left coronary variant--the anterior left, the posterior left and the intermediate left atrial branches. At the even variant the SAN blood supply sources are the right intermediate and the anterior left atrial or the right posterior and the left posterior atrial branches. The data obtained can be used for comparison with the results of coronography to make a skilled analysis of clinical-roentgenological observations.  相似文献   

13.
The comparative analysis of the contractile function of the heart left ventricle in four species of homoeothermic tetrapods (chicken, quail, rat, sheep) who differ in their spatio-temporal pattern of ventricular excitation, heart rate, and heart weight was performed. The analysis of cardiac cycle structure was performed on the basis of synchronous recording of ECG, phonocardiogram, and apex cardiogram. Indices of myocardial contractility of the left ventricle calculated on the basis of the analysis of the cardiac dynamics indicate disadvantageous contractile function of the left ventricle in rodents and non-flying birds in comparison with sheep. The functioning of the left ventricle in male rats is more strained than in female rats. One fundamental factor determining a more strained functioning of the left ventricle in birds in comparison with mammals is the heart rate. The relative weight and activation pattern of the left ventricular myocardium govern the contractile function of the left ventricle to a lesser extent.  相似文献   

14.
Hashimoto R  Sakai KL 《Neuron》2004,42(2):311-322
To identify which brain regions in adults show plasticity for learning letters, Hangul letters were experimentally associated with either speech sounds (HS condition) or nonspeech sounds (HN condition) in fMRI sessions over two consecutive days. Selective activations under the HS condition were found in several regions including the left posterior inferior temporal gyrus (PITG) and the parieto-occipital cortex (PO), as compared with activations under a condition for familiar letters and speech sounds, and with those under the HN condition. The left PITG showed a selective activation increase under the HS condition over two days, the degree of which predicted individual performance improvement. Further, functional connectivity between the left PITG and the left PO was selectively enhanced under the HS condition. These results demonstrate that a new link between orthography and phonology is formed by the plasticity of a functional system involving the left PITG in association with the left PO.  相似文献   

15.
New skeletal elements are reported of the holotype specimen Australovenator wintonensis, from the type locality, near Winton, central western Queensland. New elements include left and right humeri, right radius, right radiale, right distal carpal 1, near complete right metacarpal I, left manual phalanx II-1, left manual phalanx II-2, near complete left manual phalanx II-3 and a left manual phalanx III-3. These new elements combined with those previously described are compared against other neovenatorids.  相似文献   

16.
The left and right antennae of stingless bees have different roles in learning and recall of olfactory memory. Antennal asymmetry in social behavior is reported here. Approaches and physical contacts were scored in dyads of stingless bees (Tetragonula carbonaria): dyads in which both bees had only their right antennae (left antennae removed) made significantly more physical contacts with each other than dyads in which both bees had only their left antennae. In dyads of one left and one right, it was found, unexpectedly, that the bee with a left antenna approached the bee with the right antenna more often that the other way around, and the bee with the left antenna often attacked (by biting) its hive mate. Hence, the low number of contacts in dyads of bees using their left antennae appears to be due to mutual avoidance. Whereas use of the right antenna stimulates positive contact, the left stimulates avoidance or attack. Via such left-right asymmetries, intact bees may compute behavior directed towards friend and foe. Such antennal asymmetry may have evolved concomitantly with eusocial behavior. We found no evidence that it was associated with significant differences in the number of olfactory or non-olfactory sensilla on the left versus right antenna.  相似文献   

17.
By recombination between different mutants of mutator phages Mu and D108, we isolated a set of viable hybrids. The structure of the hybrids was analyzed by digestion with different restriction enzymes. Genetic studies show that hybrids which carry the left end of the Mu genome complement a mini-Mu deleted from within the A gene as well as Mu while hybrids with the left end of the D108 genome or D108 do not. Vice versa, hybrids with the left end of the D108 genome or D108, but not hybrids with the left end of the Mu genome or Mu complement a mini-D108 deleted from within the A gene. The nucleotide sequence of the A gene of Mu and its equivalent on D108 are mainly similar except on their left end. These observations demonstrate that the two pA products, although only partially different, have different specificities.  相似文献   

18.
This study investigates the hemodynamic changes to various types of coronary stenosis in the left coronary artery bifurcation, based on a patient-specific analysis. Twenty two patients with left coronary artery disease were included in this study. All stenoses involving the left coronary artery bifurcation were classified into four types, according to their locations: A) left circumflex (LCx) and left anterior descending (LAD), B) LCx only, C) left main stem only, and D) LAD only. Computational fluid dynamics (CFD) was performed to analyze the flow and wall shear stress (WSS) changes in all reconstructed left coronary geometries. Our results showed that the flow velocity and WSS were significantly increased at stenotic locations. High WSS was found at >70% lumen stenosis, which ranged from 2.5 Pa to 3.5 Pa. This study demonstrates that in patients with more than 50% stenosis in the left coronary artery bifurcation, WSS plays an important role in providing information about the extent of coronary atherosclerosis in the left coronary artery branch.  相似文献   

19.
李文  张鸿举  丁少娟  梁毅  刘孝钧 《生物磁学》2011,(14):2747-2749
目的:探讨急性心肌梗死(AMI)早期脑钠肽(BNP)水平与左室重构及预后的关系。方法:用放射免疫法测定AMI患者早期血浆BNP水平;用超声心动图检查测量左室收缩末容积(ESV)、左室舒张末容积(EDV)、射血分数(EF)并通过计算得左室质量(LVM)。并根据左心室容积指标分组,左心室容积增加率〉20%为左心室重构组,否则为非重构组,比较两组血浆BNP水平。结果:重构组恢复期左心室舒张末期及收缩末期容积指数均高于非重构组(P〈0.01),亦高于急性期左心室容积(P〈0.01)。重构组早期血浆BNP浓度明显高于非重构组(P〈0.01),恢复期也较非重构组高(P〈0.01)。重构组早期BNP浓度与恢复期左心室容积及容积变化量之间呈正相关。结论:AMI早期BNP升高与急性期左室重构密切相关,血浆BNP浓度可以作为溶栓治疗再通的观察指标及预后判断依据。  相似文献   

20.
Background. Left ventricular volumes, ejection fraction and regional wall motion are cardiac parameters which provide valuable information for patient management in a large variety of cardiac conditions. Differences in regional wall motion are of relevance in the field of cardiac resynchronisation therapy. We quantified three-dimensional echocardiographic measurements of left ventricular volumes, ejection and regional wall motion (e.g. expressed as systolic dyssynchrony index (SDI)) in two patient cohorts: patients with normal conduction and patients with complete left bundle branch block. Methods. Thirty-five patients scheduled for routine cardiac examination underwent three-dimensional echocardiography: 23 patients with normal conduction and 12 patients with a complete left bundle branch block. Full-volume datasets were analysed and end-systolic volume (ESV), end-diastolic volume (EDV) and ejection fraction (EF) were obtained. SDI was derived from the standard deviation of the measured times to reach minimal regional volume for each of the 16 segments of the left ventricle. Results. A significant difference was observed in left ventricular volumes, ejection fraction and SDI between the two groups. Patients with complete left bundle branch block showed higher EDV (p=0.025) and ESV (p<0.01) and a lower EF (p<0.01) than patients with normal conduction. SDI is significantly higher in patients with complete left bundle branch block (p=0.004) expressing a higher amount of ventricular dyssynchrony. Intraobserver variability showed excellent correlation coefficients: r=0.99 for EDV, ESV and SDI and r=0.98 for EF. Conclusion. Three-dimensional echocardiography is a feasible and reproducible method for the quantification of left ventricular volumes, left ventricular ejection fraction and regional wall motion. Differences can be assessed between normal patients and patients with left bundle branch block. (Neth Heart J 2007;15:89-94.)  相似文献   

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