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991.
We experienced anesthesia for total arch and descending aorta replacement and aortic valve replacement for post-repair aneurysm of coarctation of aorta and aortic stenosis. Because there was possibility that post coarctectomy syndrome would occur after repair of coarctation of aorta, administration of depressor that acts on renin-angiotensin-aldosterone and careful observation were needed postoperatively. In consideration of the development of collateral vessels, preoperative imaging evaluation was added and operative method in cardiopulmonary bypass was adjusted. Careful preoperative evaluation is very important in cardiac anesthesia.  相似文献   
992.
PurposeCongenital tracheal stenosis is a rare condition and can be difficult to manage. One source of difficulty is postoperative tracheomalacia requiring long-term tracheal stenting. To prevent symptomatic postoperative tracheomalacia, we have been adding aortopexy to tracheal reconstruction since 2008. The aim of this study was to evaluate efficacy of aortopexy for preventing postoperative tracheomalacia after reconstruction of congenital tracheal stenosis.MethodsRetrospective chart review was conducted. From October 2003 to March 2011, 24 had tracheal reconstruction without aortopexy (group A) and 8 with aortopexy (group B). Statistical analysis was performed using Fisher's Exact test.ResultsOne had anastomotic leakage in group A, and 1, in group B (P = .44). Eleven patients required tracheostomy because of postoperative tracheomalacia confirmed by postoperative bronchoscopy in group A vs none in group B (P = .029).ConclusionsWe found that aortopexy with tracheal reconstruction reduced the need for postoperative tracheostomy in this patient group. Although there is a potential risk of anastomotic leakage because of the suspension suture on the anterior tracheal wall to aorta, we did not detect an increased incidence after aortopexy. Thus, aortic suspension may be a useful adjunct to prevent symptoms of tracheomalacia in these patients.  相似文献   
993.
994.

Purpose  

Nerve growth factor (NGF) has been reported to affect synaptic transmission and cause neuropathic pain. In contrast, lidocaine has been used to reduce neuropathic pain; however, the effect of NGF and lidocaine on spontaneous transmitter release and synapse excitation has not been fully defined. Therefore, the effect of NGF and lidocaine on nerve regeneration, synapse reformation, and subsequent spontaneous transmitter release was investigated. We used Lymnaea stagnalis soma–soma-identified synaptic reconstruction to demonstrate that a transient increase in both frequency and amplitude of spontaneous events of miniature endplate potentials (MEPPs) occurs following NGF treatment and a short burst of action potentials in the presynaptic cell; in addition, the effect of lidocaine on NGF-induced synapse reformation was investigated.  相似文献   
995.

Background

Intracranial artery calcification has been reported to be an independent risk factor for ischemic stroke. Also, existence of a positive correlation has been reported between the presence of arterial calcification and that of ischemic changes in the area supplied by such arteries. While intracranial artery calcification has frequently been observed on computed tomographic (CT) images of the brain in hemodialysis patients, its prevalence has not been reported previously. We investigated our hemodialysis outpatients to determine the prevalence of intracranial artery calcification in these patients in comparison with that in healthy controls.

Methods

Brain CT examinations were performed in 107 patients under maintenance hemodialysis therapy. For comparison, 43 representatives of the general population who underwent a brain CT examination as part of a health checkup were also studied as control subjects.

Results

Intracranial calcifications were more frequently found among hemodialysis patients (87.9%) than among control subjects (53.5%, P?=?0.0003), and the prevalences of calcification in each of the intracranial arteries in the two groups were as follows: vertebral artery (65.5% vs. 25.6%, P?=?0.0002), internal carotid artery (62.1% vs. 18.6%, P?<?0.0001), basilar artery (34.5% vs. 34.9%, ns), anterior cerebral artery (0 vs. 2.3%, ns), middle cerebral artery (24.1% vs. 20.9%, ns), and posterior cerebral artery (5.2% vs. 4.7%, ns).

Conclusions

A much higher rate of intracranial artery calcification was observed in hemodialysis patients than in the general population, and the most frequently involved sites of calcification in these patients were the relatively large intracranial arteries.  相似文献   
996.

Background

Neoadjuvant chemotherapy (NAC) is the standard treatment for locally advanced breast cancer. It is now being used to treat operable breast cancer to facilitate breast-conserving surgery, but the accuracy of sentinel lymph node biopsy (SLNB) in breast cancer patients receiving NAC remains open to considerable debate.

Methods

We enrolled 96 patients with stage II–III breast cancer who received NAC from January 2001 to July 2010. All patients underwent breast surgery and SLNB, followed immediately by complete axillary lymph node dissection (ALND). Sentinel lymph nodes were detected with blue dye and radiocolloid injected intradermally just above the tumor and then evaluated with hematoxylin and eosin and immunohistochemical staining.

Results

The overall identification rate for SLNB was 87.5?% (84/96); the false negative rate (FNR) was 24.5?% (12/49); and the accuracy rate was 85.7?% (72/84). The FNR was significantly lower in clinically node-negative patients than in node-positive patients before NAC (5.5?% vs. 35.5?%; p?=?0.001). Accuracy was also significantly higher in clinically node-negative patients than in node-positive patients before NAC (97.2?% vs. 77.1?%; p?=?0.009). The FNR was 27.3?% among 46 clinically node-positive patients before NAC who were clinically node-negative after NAC. Among 12 patients with a complete tumor response (CR), the FNR was 0?%, compared with 26.1?% for 83 patients with a partial response and stable disease (p?=?0.404).

Conclusions

Although associated with a high FNR after NAC, SLNB would have successfully replaced ALND in clinically node-negative patients before NAC and in patients with a CR after NAC.  相似文献   
997.
998.
An hourglass-like constriction is a focal fascicular lesion observed in one or a few places in one or a few fascicles of a peripheral nerve trunk, and usually affects the anterior interosseous (AIN) or posterior interosseous (PIN) nerve. Constrictions have previously been discovered only by surgical exploration, and have been unable to be recognized on pre-operative imaging. We encountered some cases in which the lesion was able to be diagnosed pre-operatively by high-resolution ultrasonography; these findings were then confirmed intra-operatively. Five consecutive cases were included in this study. In three cases with constrictions revealed on pre-operative ultrasound, the findings were confirmed intra-operatively. In the remaining two cases in which no constrictions were detected pre-operatively, no constriction was revealed intra-operatively. High-resolution ultrasonography may play a significant role in the diagnosis of hourglass-like constrictions, and may thus lead to significant changes in treatment strategies for AIN and PIN palsy.  相似文献   
999.
1000.
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