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1.
Objective. Tympanic temperature can be obtained instantaneously using an infrared emission detection (IRED) thermometer. Its accuracy has been documented in a variety of clinical settings, but its performance at low body temperatures is still unknown. In this study we evaluated its performance during coronary artery revascularization surgery in which mild hypothermic cardiopulmonary bypass (CPB) was used. Methods. Thirty adult patients undergoing coronary artery bypass graft surgery were enrolled in the study. Tympanic temperature obtained using IRED thermometry (Tt1) was compared with core temperatures from the esophagus (Te), and venous blood of CPB (Tv) before, during, and after CPB. We also measured tympanic temperature using a thermocouple probe (Tt2) in 16 of the 30 patients in order to study the agreement between the two methods. Values for correlation coefficients and limits of agreement were computed to assess the degree of agreement among the temperatures obtained. Results. The highest agreement with Tv during CPB was obtained from Tt1 (r = 0.94, 0.41 ± 1.73, limits of agreement) and from Te (0.91, 0.36 ± 2.46). Tt1 also showed good agreement with Tt2 during surgery. Conclusions. Infrared tympanic thermometry is a reliable, alternative method to measure tympanic temperature and may be useful to assess core temperature in both normothermic and mild hypothermic conditions.  相似文献   
2.
STUDY OBJECTIVE--The aim was to clarify the inhibitory effect of the selective kappa agonist, spiradoline, on coronary arterial smooth muscle in relation to the intracellular Ca2+ concentration. DESIGN--The inhibitory effect of spiradoline was investigated (1) on the contractile response of pig coronary artery to the readmission of Ca2+, following initial exposure to Ca2+ free medium and depolarisation with 40 mM K+; (2) on the intracellular Ca2+ concentration as assessed using the fluorescent calcium indicator fura-2. Relaxant responses to spiradoline in isolated porcine coronary artery strips contracted with K+ and prostaglandin F2 alpha were also examined. EXPERIMENTAL MATERIAL--Coronary arteries isolated from pigs of both sexes were used. The right and left circumflex coronary arteries were cut into 3 mm wide strips which were used to measure the change in contractile force and the intracellular Ca2+ concentration. MEASUREMENTS AND MAIN RESULTS--Prior treatment with spiradoline at 2 x 10(-6) mol.litre-1 or more inhibited the contractile response to the readmission of Ca2+ in porcine coronary artery exposed to Ca2+ free medium in the presence of high K+. Naloxone at 3 x 10(-4) mol.litre-1 did not reverse the inhibitory action of 2 x 10(-5) M spiradoline. Ca2+ induced contraction was inhibited completely by 10(-4) M spiradoline. Moreover, spiradoline caused relaxation in arterial preparations that had been contracted with K+ (15 to 25 mmol.litre-1) or prostaglandin F2 alpha (10(-6) to 3 x 10(-6) mol litre-1), greater relaxation being seen in the K+ induced contraction. The intracellular Ca2+ concentration was significantly lowered by 2 x 10(-5) M spiradoline. CONCLUSIONS--The relaxant response of coronary artery to spiradoline is, in part, attributable to interference with Ca2+ entry into the arterial smooth muscle.  相似文献   
3.
A 10-year-old girl having bilateral subclavian steal associated with severe coarctation of the thoracic aorta and an aberrant right subclavian artery was found, on admission, to have no difference between upper and lower extremity blood pressure, but echocardiography revealed severe thoracic aorta coarctation and systolic blood pressure in the carotid arteries exceeding 200 mmHg estimated by Doppler ultrasonography. Magnetic resonance imaging and angiography demonstrated bilateral subclavian steal without esophageal compression. We reconstructed the aortic arch using the left subclavian artery and a reversed Blalock-Park procedure, then repaired the coarctation with a 14 mm woven double velor vascular graft. The girl was symptom-free following uncomplicated recovery from surgery. Doppler ultrasonography 2 weeks after surgery showed the pressure gradient across the aortic arch had decreased from 180 mmHg to 60 mmHg. This residual gradient at the anastomosis between the ascending aorta and left subclavian artery may improve as native vessels grow.  相似文献   
4.
Myocardial oxygen consumption (MVO2) includes components for 1) mechanical energy generation, 2) activation, and 3) basal metabolism. Whereas the first two components are expected to increase in proportion with heart rate, a significant basal level of metabolism would consume oxygen even if the heart rate were zero. Contrary to this expectation, however, a previous study reported that, during unloaded beats, MVO2 per beat (which includes basal metabolism) was independent of heart rate. Accordingly, unloaded MVO2 per minute would extrapolate to zero at zero heart rate; this result is unexpected considering basal metabolism. To resolve this inconsistency, we varied heart rate over a wide range after inducing atrioventricular block in eight isolated cross-circulated canine hearts that contracted isovolumically. We examined whether a term representing rate-independent basal metabolism was needed to describe MVO2 per minute. Mechanical energy generated by the left ventricle was evaluated from the pressure-volume area, which was altered by changing isovolumic ventricular volume over at least five levels at each heart rate. Contractility, evaluated by the slope of the end-systolic pressure-volume relation, did not vary significantly with heart rate in this study. In contrast to the previous report, unloaded MVO2 per beat (i.e., MVO2 extrapolated to a pressure-volume area of zero) was not constant but fell monotonically with increases in heart rate in every heart. We considered that this trend was caused by a significant rate-independent basal level of MVO2 per minute. Multiple linear regression analysis confirmed that this rate-independent basal term differed significantly from zero in seven of the eight hearts studied.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
Prosthetic valve endocarditis (PVE) caused by Candida species is associated with high morbidity and mortality. A combination of surgical resection and antifungal drug therapy is the golden standard for treatment, yet surgical intervention is not possible in all cases of Candida PVE. We report a case of PVE due to Candida albicans cured by medical treatment alone. This case suggests that, in some instances, Candida PVE can be managed medically with antifungal therapy. Such a conservative approach should be applied with caution and necessitates very close follow-up on a long-term basis.  相似文献   
6.
We describe a case of successful combined repair of the aortic and mitral valves for an indication of active infective endocarditis involving both valves. Mitral valve repair was achieved by vegetation debridement, fixation of the anterior mitral commissure, resection and suturing of the posterior mitral leaflet, and posterior annuloplasty with autologous pericardium. Aortic valve repair was achieved by vegetectomy and commissural plication. Postoperative clinical course was without signs of recurrent infection, and echocardiogram demonstrated mitral valve competence with trivial aortic regurgitation. We concluded that simultaneous valve repair is a viable option in the context of active endocarditis.  相似文献   
7.
A filing system for ocular fundscopic image data was developed by using a personal computer for the Twin AMHTS. The development of the system was tried as one of the data transfer system including image data between two similar AMHTSs named the Twin AMHTS through the information network system. The filing system is capable of storing 26782 data of ophthalmoscopic pictures with a data compression mode by using a magneto-optical disk (MOD) whose storage capacity of both sides is 616 MB. It takes no long time for retrieval and display of the image data in the filing system. Good quality of compression and decompression obtained and reproducibility of the ocular fundus picture is favorable regardless of normal or abnormal cases. As a result, it is suggested that the developed system has practical utility although it requires more improvement.  相似文献   
8.
9.
OBJECTIVE: To determine how sleep with central spindles alters the spatial distribution of interictal spike frequency in children with intractable focal seizures, and whether such children have spindles arising from the medial temporal region in addition to the frontal-central region. METHODS: Seventeen children (age: 7 months-17 years) were studied using extraoperative electrocorticography (ECoG). RESULTS: Overall spike frequency across the subdural electrodes was greater during sleep with central spindles compared to wakefulness. In 13 children showing at least 1 spike/min in an electrode, the spatial distribution of spike frequency was similar during wakefulness and sleep; in addition, the spike frequency was greater in the seizure onset zones compared to the non-onset areas, regardless of wakefulness or sleep. Spindles were identified in the medial temporal region during sleep with central spindles in all 17 children. CONCLUSION: Overall spike frequency may be increased by sleep with spindles, but the spatial distribution of spike frequency appears similar during wakefulness and sleep in children with intractable focal seizures. SIGNIFICANCE: Both awake and sleep ECoG may be useful to predict seizure onset zones in children with intractable focal epilepsy. Medial temporal spindles are present in some children with focal epilepsy.  相似文献   
10.
An unusual case of Cushing's syndrome of a 59-year-old man with bilateral multinodular adrenal hyperplasia and microadenoma of the pituitary gland is presented. Failure to suppress plasma Cortisol with large doses of dexamethasone may suggest autonomous growth of hyperplastic nodules of the adrenals, which were at first induced by prolonged stimuli of ACTH from the microadenoma of the pituitary gland. ACTH could not be detected in the microadenoma cells on paraffin sections, while Crooke's cells were strongly positive for ACTH. The interrelation between bilateral multinodular adrenal hyperplasia and pituitary microadenoma is discussed.  相似文献   
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