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51.
Poor distal runoff and hyperlipidemia are factors affecting the fate of an implanted graft. In the present study, combined effects of poor distal runoff and hyperlipidemia on intimal hyperplasia (IH) of the vein graft were examined in a newly developed poor distal runoff model in rabbits. A poor distal runoff model was prepared in the right hindlimb of 30 rabbits. These animals were divided into two groups, depending on the diet provided; normolipidemic diet group (Group NL, n = 14) and hyperlipidemic 1% cholesterol diet group (Group HL, n = 16). Four weeks after preparing the poor runoff model, the femoral vein was implanted into the ipsilateral femoral artery. At 2, 4 and 6 weeks, the grafts were harvested. IH of the graft was measured and macrophages in the IH were examined immunohistochemically. Intimal cell proliferation was also determined by bromodeoxyuridine (BrdU) incorporation. IH of the vein graft was significantly accelerated in cases of poor distal runoff and hyperlipidemia. There were no macrophages in the IH in the NL group. In the HL group, macrophages infiltrated the outer layer of IH, sometimes just above the internal elastic lamina, and increased with time. In the poor distal runoff limbs at 6 weeks, macrophages also appeared in the subendothelial layer but were absent in that layer in the controls. Intimal cell proliferation expressed as the Brd U labeling index (LI) was maximum at 2 weeks. In the HL group, BrdU LI of 1H in the poor distal runoff limb was higher than in the control at 2 and 4 weeks. Throughout the experiments, BrdU Us in the HL group were significantly higher than in the NL. Hyperlipidemia accelerates intimal cell proliferation to a greater extent, then does 1H. In cases of a poor distal runoff, the enhancement of cell proliferation by hyperlipidemia is augmented. These responses, in the presence of a hyperlipidemia, may be closely related to the migration of macrophages.  相似文献   
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Our aim was to investigate the prognosis of patients with squamous cell carcinoma (SCC) of the gingiva who had preoperative dental operations. We studied 102 patients who were being operated on for SCC of the gingiva with special reference to the effects of preoperative dental operations on the prognosis. Twenty-six patients had dental procedures such as tooth extraction, or incision, or curettage before they visited our hospital, while the remaining 76 had no such interventions. The percentage of patients with advanced T stage disease (T3 or T4) was higher among those who had interventions (17/26, 65%) than among those who had not (35/76, 46%). The difference was not significant. Histopathologically invaded nodes were detected in half the patients in the intervention group (13/26), while they were found in only 18/76 (24%) of those in the no intervention group (p < 0.02). The incidence of nodal metastases with extranodal spread was significantly higher in the intervention group than in the no intervention group (p < 0.05), and those in the intervention group were more likely to develop distant metastases than those in the other group (p < 0.001). The 5-year survival in the two groups was 65% and 92%, respectively (p < 0.01). Preoperative dental operations such as tooth extraction, incision, or curettage possibly lead to regional and distant metastases and therefore a poor prognosis in patients with SCC of the gingiva.  相似文献   
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IntroductionIn this study, we investigated whether such a discontinuation of oral bisphosphonate (BP) for 3 months might influence the incidence of BP-related osteonecrosis of the jaw (BRONJ) and wound healing after tooth extraction in patients receiving oral BP therapy.Material and methodsThere were a total of 434 teeth in 201 patients (18 males and 183 females). The patients were divided into two groups depending on whether or not they underwent a 3-month discontinuation of BP therapy (BP? and BP+) before tooth extraction. In this observational study investigated delayed wound healing after tooth extraction in patients receiving oral BP therapy.ResultsIn all cases of the BP? group, there were no BRONJ although there was delayed wound healing in two cases. However, in one case of the BP+ group, oral BP was continued because it was deemed high risk to discontinue treatment by the patient's physician. In this case, an intraoral fistula was still present with bone exposure at 120 weeks after extraction (BRONJ stage 1).ConclusionThis study supports the idea of a drug holiday and encourages further clinical research on this topic of tooth extraction in patients receiving oral BP therapy.  相似文献   
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Background

Surgical resection is the most effective treatment for colorectal cancer that has metastasized to the liver. Similarly, surgical resection improves survival for selected patients with pulmonary colorectal metastases. However, the indication for pulmonary metastasectomy is not clear in patients with both hepatic and pulmonary colorectal metastases. Therefore, we evaluated outcomes after pulmonary resection of colorectal metastases in patients with or without a history of curative hepatic metastasectomy.

Methods

We retrospectively analyzed 96 patients who underwent pulmonary metastasectomy from March 1999 to November 2009. Patients were grouped according to treatment: resection of pulmonary metastases alone (lung metastasectomy group) or resection of both hepatic and pulmonary metastases (liver and lung metastasectomy group). Overall survival (OS) and disease-free survival (DFS) were evaluated by Kaplan–Meier analysis. Survival curves were compared using the log-rank test.

Results

The 5-year OS for all patients was 61.3 %, and the 5-year DFS was 26.7 %. Group comparisons showed that the 5-year OS of the lung metastasectomy group was significantly better than that of the liver and lung metastasectomy group (69 vs. 43 %; p = 0.030). However, the 5-year DFS rates of the lung metastasectomy group (25.8 %) and liver and lung metastasectomy group (28.0 %) did not differ significantly. Recurrence was higher after resection of both hepatic and pulmonary metastases than after pulmonary metastases alone (79 vs. 45 %; p = 0.025).

Conclusions

Resection of pulmonary colorectal metastases may increase survival. However, the combination of liver and lung metastasectomies had a worse prognosis than pulmonary metastasectomy alone. In selected patients, combined liver and lung metastasectomy can be beneficial and result in acceptable DFS.  相似文献   
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Introduction

Juvenile xanthogranuloma (JXG) preferentially occurs in childhood, and its characteristics have been thought to be benign and with slow growth. JXG is classified as an inflammatory disease, which forms multiple lesions in the patients’ head, neck, and other organs and typically skin. JXG is rare, and few case reports have been published in the past, particularly with multiple intracranial lesions, which as in our case, is an extremely rare finding.

Case

Patient is a 4-year-old boy who presented with polydypsia and polyuria for 1 year. He had been followed up only under l-deamino-8-d-arginine vasopressin until he started vomiting and his level of consciousness deteriorated. Then, magnetic resonance imaging (MRI) revealed multiple intracranial lesions. He underwent biopsy via small craniotomy, and pathology was confirmed as juvenile xanthogranuloma. The patient received chemotherapy, in complete compliance with JLSG-02 protocol.

Findings

JXG is characteristic with homogenous enhancement with contrast matter and, most importantly, high intensity on diffusion-weighted image (DWI). The DWI was high when the degree of diffusion of water is restricted, as seen in inflammation and, additionally, the change of intensity after administration of steroid would reflect its anti-inflammatory nature. However, though the steroid therapy made high-intensity lesions decrease signal intensity, the size and the number of lesions did not change at all. As we expected, after we stopped steroid administration to the patient, his consciousness deteriorated and we found again the very-high-intensity lesions. We consider the intensity on DWI to reflect progression of the lesions.  相似文献   
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