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101.
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Changes in preference are inherently subjective and internal psychological events. We have identified brain events that presage ultimate (rather than intervening) choices, and signal the finality of a choice. At the first exposure to a pair of faces, caudate activity reflected the face of final choice, even if an initial choice was different. Furthermore, the orbitofrontal cortex and hippocampus exhibited correlations only when the subject had made a choice that would not change.  相似文献   
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Dynamic motion of the pelvic floor muscles during voiding was analyzed using real‐time magnetic resonance imaging. To evaluate the contraction of the pelvic floor muscles, striated urethral sphincter distance, levator ani muscle thickness and anterior fibromuscular stroma distance were measured. The percent contraction of the striated urethral sphincter from before voiding to just before initiation of voiding was 14% in the normal group and 5% in the voiding dysfunction group. The percent contraction of the anterior fibromuscular stroma from before voiding to just before initiation of voiding was 11% in the normal group and 1% in the voiding dysfunction group; the percent contraction of the muscles was significantly greater in the normal group (P < 0.05). Striated urethral sphincter and anterior fibromuscular stroma contraction at initiation of voiding open the bladder neck and urethra. This plays an important role in the smooth initiation of voiding.  相似文献   
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Takotsubo cardiomyopathy is an acute syndrome involving apical ballooning and consequent dysfunction of the left ventricle. Most cases of left ventricular dysfunction resolve within 1 month. We present the case of a 40-year-old woman who developed severe heart failure caused by takotsubo cardiomyopathy with severe left ventricular dysfunction during the perinatal period. Because of the presence of multiple myomas, she was scheduled to undergo a cesarean section under general anesthesia. However, after induction of general anesthesia, she had to be awakened because of the presence of a difficult airway. Because she exhibited insufficient oxygenation, she was transferred to the emergency center. Upon hospital admission, she expectorated large amounts of pink sputum, indicating severe pulmonary edema. Cesarean section was performed immediately. Echocardiography revealed severe left ventricular dysfunction. Full recovery of cardiac function required almost 1 month, after which she was discharged from the hospital without further complications. This is the first reported case of takotsubo cardiomyopathy induced by a failed intubation during a scheduled cesarean section. Takotsubo cardiomyopathy usually shows a good prognosis, but if this myopathy develops during the perinatal period, it can worsen because of excessive preload following the termination of fetoplacental circulation.  相似文献   
107.
Sinus bradycardia is a well-known consequence of stimulation of presynaptic α2 adrenergic receptors due the adminstration of dexmedetomidine. One of the most serious adverse effects of dexmedetomidine is cardiac arrest. Some cases demonstrating such an arrest due to the indiscriminate use of this drug were recently reported. We continuously administered dexmedetomidine to a 56-year-old male patient at a rate of 0.3 μg/kg/h (lower than the recommended dose) without initial dosing for sedation in an intensive care unit. The patient had undergone open cardiac surgery and atrial pacing was maintained at a fixed rate, 90/min. The PQ interval in electrocardiography gradually prolonged during the infusion; finally, complete atrioventricular block and subsequent cardiac arrest occurred. Immediate cardiopulmonary resuscitation was carried out, including re-intubation, and recovery of spontaneous circulation was attained 15 min after the event. The patient was discharged from hospital on the 25th postoperative day without any neurological complications.  相似文献   
108.
Splenectomy is an effective technique in living donor liver transplantation (LDLT) with small‐for‐size (SFS) liver grafts for overcoming SFS liver graft injury. However, the protective mechanism of splenectomy is still unclear. The aim of this study was to investigate how splenectomy could attenuate SFS graft injury through the measurement of biochemical factors, particularly the expression of endothelin (ET)‐1, which is a key molecule of microcirculatory disorders by mediating sinusoidal vasoconstriction. We performed rat orthotopic liver transplantation using SFS liver grafts with or without splenectomy. We investigated intragraft expression of ET‐1 mRNA and hepatic protein levels of ET‐1. In addition, portal pressure, hepatic injury and morphological changes, and survival rate were evaluated. In result, intragraft ET‐1 mRNA expression after SFS liver transplantation was significantly downregulated by splenectomy, and hepatic expression of ET‐1 in SFS grafts was rarely observed. Splenectomy inhibited the increase in portal pressure, ameliorated SFS liver graft injury and improved the graft survival rate after SFS liver transplantation. In conclusion, splenectomy improved the SFS liver injury and decreased the expression of ET‐1 by attenuating portal hypertension on SFS liver transplantation. Downregulation of intragraft ET‐1 expression plays important roles in the protective mechanism of splenectomy in SFS liver transplantation.  相似文献   
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Objective  Recent evidence demonstrated that hypercapnic acidosis due to lung protective strategy was not only permissive but also even therapeutic for injured lung. Since the effects of hypercapnic acidosis on extra-pulmonary organs remain to be clarified, we tested the hypothesis that hypercapnic acidosis protects gut mucosal barrier function by modulating inflammation in a rabbit model of endotoxemia. Design  Prospective randomized animal study. Setting  University research laboratory. Subjects  Male New Zealand white rabbits. Interventions  Thirty-two animals were randomly allocated into two groups: normocapnia (n = 17) and hypercapnia (n = 15). The latter group received FICO2 5% under mechanical ventilation to achieve hypercapnia throughout the study periods, whereas the former with FICO2 0%. Measurements and results  Arterial blood gas, intramucosal pH (pHi) and portal blood flow were assessed at baseline, 2-h and 4-h infusion of lipopolysaccharide. At 4 h, ileal myeloperoxidase (MPO) activity and intestinal permeability were measured. The animals in the hypercapnia group showed apparent hypercapnic acidosis and progressive intramucosal acidosis at 4 h, accompanied by significantly lower intestinal permeability versus normocapnia group. Ileal MPO activity was comparable between the study groups. Conclusions  Hypercapnic acidosis attenuates endotoxin-induced gut barrier dysfunction possibly through neutrophil-independent mechanisms. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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