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1.
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.  相似文献   
2.
BACKGROUND/AIMS: The purpose of this work was to develop a new sensor for objective in vivo measurement of the cutaneous temperature based on micro-electro-mechanical systems (MEMS), and to compare these performances with those of a classical thermocouple. Research on this new sensor was carried out to allow the quantification of the thermal properties of the made-up skin. METHODS: Sixteen female subjects divided into two different age groups (18-35 and >50 years old) were recruited for this study. Several zones of the face and forearms were made up at random with foundations containing or not a thermoregulator raw material. The quantity of foundation applied on the skin was standardized and measurements were carried out first before make-up, and then 10 s and 5 min after make-up. The new sensor and the thermocouple were used successively on each zone. The cutaneous temperature was expressed in degrees celsius. RESULTS/CONCLUSION: The two systems are similar in terms of repeatability and reproducibility, with some differences in sensibility. The data measured by the MEMS sensor appear lower than those measured by the thermocouple. After make-up, the MEMS sensor detects a progressive increase of the temperature in time whereas the thermocouple detects a decrease. We found the same evolution on the face but in a more attenuated way. These results tend to show that the devices do not measure the same phenomenon. The thermocouple appears more sensitive to the thermal response of the made-up surface whereas the MEMS sensor appears more sensitive to the heat transfers in the interface between the skin and make-up.  相似文献   
3.
4.
The application of spin-echo magnetic resonance imaging sequences on non-invasive temperature imaging for temperature mapping of human limbs is investigated. In an in vitro expriment performed on a meat sample, the equilibrium magnetisation P and the spin-lattice relaxation time T1 are calculated from the values for the repetition time TR and the signal intensities obtained by a spin-echo sequence at different tissue temperatures tures as measured by a fibre-optic probe. T1 is linearly correlated to the tissue temperature, and P is linearly correlated to the reciprocal value of the absolute temperature. Both effects, taken together, lead to a non-linear dependency of the signal intensity on temperature. Therefore a TR leading to maximum temperature dependency of the signal intensity is calculated and used in the futher experiments. In the in vivo experiments, the lower legs of two volunteers are cooled from outside. Images are acquired with a spin-echo sequence (1.5T, TR=1200 ms, TE=10 ms). A rise in signal intensity in the muscle with falling skin temperature is observed, particularly in more peripheral muscle layers. This study shows that spin-echo sequences can be used to monitor temperature changes and temperature differences in living muscle tissue.  相似文献   
5.
甲基强的松龙对低温保存大鼠肝脏的保护作用   总被引:2,自引:1,他引:1  
应用Wistar大鼠肝脏离体灌流模型,用CMU—1号液,含有甲基强的松龙的CMU—1号液,以及缺血前预用甲基强的松龙后再用CMU—1号液分别对肝脏进行灌洗保存。检测LDH、ALT、肝组织匀浆SOD活性和MDA含量,并观察肝组织结构。结果表明:甲基强的松龙对低温保存的离体大鼠肝脏具有保护作用  相似文献   
6.
Summary Thermoregulatory sweating [total body (m sw,b), chest (m sw,c) and thigh (m sw,t) sweating], body temperatures [oesophageal (T oes) and mean skin temperature (T sk)] and heart rate were investigated in five sleep-deprived subjects (kept awake for 27 h) while exercising on a cycle (45 min at approximately 50% maximal oxygen consumption) in moderate heat (T air andT wall at 35° C. Them sw,c andm sw,t were measured under local thermal clamp (T sk,1), set at 35.5° C. After sleep deprivation, neither the levels of body temperatures (T oes,T sk) nor the levels ofm sw, b,m sw, c orm sw, t differed from control at rest or during exercise steady state. During the transient phase of exercise (whenT sk andT sk,1 were unvarying), them sw, c andm sw, t changes were positively correlated with those ofT oes. The slopes of them sw, c versusT oes, orm sw, t versusT oes relationships remained unchanged between control and sleep-loss experiments. Thus the slopes of the local sweating versusT oes, relationships (m sw, c andm sw, t sweating data pooled which reached 1.05 (SEM 0.14) mg·cm–2·min–1°C–1 and 1.14 (SEM 0.18) mg·cm–2·min–1·°C–1 before and after sleep deprivation) respectively did not differ. However, in our experiment, sleep deprivation significantly increased theT oes threshold for the onset of bothm sw, c andm sw, t (+0.3° C,P<0.001). From our investigations it would seem that the delayed core temperature for sweating onset in sleep-deprived humans, while exercising moderately in the heat, is likely to have been due to alterations occurring at the central level.  相似文献   
7.
Measurements of toe temperature and transcutaneous PO2 (PtcO2) have been both suggested for non-invasive assessment of peripheral blood flow in acute circulatory failure. The underlying principle of the two methods is that cutaneous vasoconstriction occurs early when tissue perfusion is altered. In 15 patients, we compared the two measurements during cardiogenic shock (27 measurements) or septic shock (29 measurements). Toe-ambiant temperature gradient and PtcO2 correlated well together (r=0.66, p(0.001) especially in hyperkinetic septic shock (r=0.79, p(0.001). In cardiogenic shock, toe-ambiant temperature correlated well with cardiac index (r=0.63), stroke index (r=0.64) and oxygen transport (r=0.65), and these correlations were stronger than for PtcO2. In septic shock, both techniques were poor indicators of blood flow indexes but PtcO2 rather correlated with arterial pressure (r=0.66) and left ventricular work (r=0.66). Trend evaluation of data revealed in cardiogenic shock that the increase in toe temperature usually preceded the increase in PtcO2. Since measurement of PtcO2 is technically more complicated, correlates less well with standard hemodynamic parameters and later reflects cardiovascular improvement, it has no advantage over measurement of toe temperature in circulatory shock. In cardiogenic shock, measurements of toe temperature can reliably track cardiac output changes. In septic states, however, non-invasive assessment of skin perfusion is of limited interest.  相似文献   
8.
Summary Stress-induced hyperthermia (SIH), which is seen in the last mice removed from the cage, is a novel animal model sensitive to anxiolytic drugs. SIH is antagonized by CL 218872 (25 and 50 mg/kg, os), by tracazolate (5 and 7.5 mg/kg, ip) and by 2-AP-5 (50 and 100 mg/kg, ip). At higher dose, CL 218872 (100 mg/kg, os) and tracazolate (12.5 mg/kg, ip) lose their activity.PK 9084 (5–40 mg/kg, ip) and CGS 9896 (2–20 mg/kg, both ip and os) were also ineffective in preventing SIH. The anti-hyperthermic effect of CL 218872 (25 mg/kg) and tracazolate (7.5 mg/kg) was blocked by the benzodiazepine antagonist Ro 15–1788 (15 mg/kg). CGS 9896 (10 mg/kg, os) also reversed the effect of CL 218872 (25 mg/kg) on SIH.Differently from anxiolytics, MK-801 (0.5–1 mg/kg, os), PCP (2.5 mg/kg, ip) and d-amphetamine (10 mg/kg, ip) evoked hyperthermia in the first set of mice and prevented a further stress-induced rise of body temperature in the last set of mice.  相似文献   
9.
64层螺旋CT诊断先天性冠状动脉起源异常的价值   总被引:1,自引:0,他引:1  
目的:探讨64层螺旋CT冠状动脉造影诊断冠状动脉起源异常的临床价值。材料和方法:回顾性总结2005年12月至2006年12月间1800例64层螺旋CT冠脉造影的结果,统计冠状动脉起源异常的发生率。结果:1800例检查者中发现冠脉起源异常51例,发病率2.8%。包括右冠状动脉变异11例(21.6%)、左冠状动脉变异8例(15.7%)、左右冠均发生变异1例(2%)、单支冠状动脉1例(2%)、分支变异28例(54.9%)。结论:64层螺旋CT是诊断冠状动脉起源异常的安全有效方法,对临床治疗有重要的意义。  相似文献   
10.
合并异常冠状动脉法洛四联症和右心室双出口一期根治术   总被引:3,自引:0,他引:3  
目的 总结合并异常冠状动脉的法洛四联症和右心室双出口一期根治术的经验,探讨有关外科技术的改进。方法1995年6月至2002年6月完成该类一期根治术12例,其中2例采取了肺动脉移位、3例在游离的左前降支下加宽右室流出道、5例改变右室切口并在冠状动脉下缝合、2例经肺动脉和右房疏通流出道。结果无手术死亡。随访3个月~6年,无晚期死亡和并发症发生。结论合并异常冠状动脉的法洛四联症和右心室双出口的一期根治手术是可行的,且效果良好,但必须采用适当的外科技术以保护异常的冠状动脉。  相似文献   
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