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971.
Recently, due to increases in the number of cardiac device implantations, especially implantable cardioverter-defibrillators and cardiac resynchronization therapy, device complications have been experienced more frequently. Myocardial perforation of an implanted lead is one of the most severe complications. We report a case of ventricular lead perforation clearly visualized by 3-dimensional echocardiography, which was not identified by 2-dimensional echocardiography.  相似文献   
972.
Spinal extradural arachnoid cysts are rare expanding lesions, and their etiology is mainly unknown. The authors present a rare case of metastatic pancreatic cancer presenting as an arachnoid cyst of the cervical spine. A 61-year-old woman with progressive neurological deficits was presented with a very large cystic mass from C3 to C6 and C7 and T1 that was a metastatic lesion causing severe collapse of vertebral bodies and subluxation. A posterior laminectomy from C3 to C6 for excision of the cysts and marginal excision including laminectomy around C7 and T1 were performed with instrumented fusion to prevent further collapse and subluxation of T1. No communication between the cysts and the subarachnoid space was found in the surgical field. The neurological symptoms rapidly improved immediately after the surgery. The histology of resected specimens was metastatic mucin-producing adenocarcinoma. This report describes a rare case of metastasis of pancreatic cancer presenting as an arachnoid cyst of the cervical spine. The significance of this study is that metastatic cystic lesions from pancreatic cancer should be considered in the differential diagnosis of arachnoid cysts of the spinal canal.  相似文献   
973.
Lee BJ  Lee HS  Kim CD  Jung SW  Seo YS  Kim YS  Jeen YT  Chun HJ  Um SH  Lee SW  Choi JH  Ryu HS 《Gut and liver》2012,6(2):262-269

Background/Aims

Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors (statins) and peroxisome proliferator-activated receptor gamma (PPARγ) ligands can modulate cellular differentiation, proliferation, and apoptosis through various pathways. It has been shown that HMG-CoA reductase inhibitors and PPARγ agonists separately inhibit pancreatic stellate cell (PaSC) activation. We studied the effects of a combination of both types of drugs on activated PaSCs via platelet-derived growth factor (PDGF), which has not previously been reported. The present study was performed to elucidate the underlying mechanisms of these effects by focusing on the impact of the signaling associated with cell-cycle progression.

Methods

Primary cultures of rat PaSCs were exposed to simvastatin and troglitazone. Proliferation was quantified using the BrdU method, and cell-cycle analysis was performed using a fluorescent activated cell sorter. The protein expression levels of smooth muscle actin (SMA), extracellular signal-regulated kinase (ERK), and a cell cycle machinery protein (p27Kip1) were investigated using Western blot analysis.

Results

Simvastatin reversed the effects of PDGF on cell proliferation in a dose-dependent manner. The combination of a low concentration of simvastatin (1 mM) and troglitazone (10 mM) synergistically reversed the effects of PDGF on cell proliferation but had no effect on cell viability. The expression of a-SMA was markedly attenuated by combining the two drugs, which blocked the cell cycle beyond the G0/G1 phase by reducing the levels of phosphorylated ERK and reversed the expression of p27Kip1 interrupted by PDGF.

Conclusions

Simvastatin and troglitazone synergistically inhibited cell proliferation in activated PaSCs by blocking the cell cycle beyond the G0/G1 phase. This inhibition was due to the synergistic modulation of the ERK pathway and the cell cycle machinery protein p27Kip1.  相似文献   
974.

Background/Aims

Although several groups have demonstrated the usefulness of natural orifice transluminal endoscopic surgery (NOTES), there is still concern about frequent serious adverse events. We performed this study to determine the technical feasibility and safety of pure NOTES with a transgastric approach in a porcine model from the endoscopist''s point of view.

Methods

Diagnostic peritoneoscopy, liver biopsy, salpingo-oophorectomy, and Fallopian tube ligation with a transgastric approach using a two-channel therapeutic endoscope were performed in 10 healthy female minipigs. These procedures were performed in two acute models and eight survival models in consecutive order.

Results

The technical success rate was 100% for peritoneoscopy (10/10), liver biopsy (5/5), salpingo-oophorectomy (10/10), and Fallopian tube ligation (10/10). Eight cases of adverse events occurred, including one case of splenic injury, one case of bleeding after liver biopsy, two cases of small bowel adhesion after salpingo-oophorectomy, two cases of hematoma at the salphingo-oophorectomy site, and two cases of partial dehiscence at the gastric closure site. The gastric puncture site was closed with seven to eight hemoclips in four cases and two hemoclips and an endoloop in four cases.

Conclusions

The use of pure NOTES for peritoneoscopy, liver biopsy, salpingo-oophorectomy, and Fallopian tube ligation may be technically feasible, but considerable adverse events can occur during or after the procedure. Further studies utilizing specialized techniques overcome several limitations of pure NOTES are therefore necessary.  相似文献   
975.

Purpose

There have been reports that radiofrequency ablation (RFA) combined with transarterial chemoembolization (TACE) is as equally effective as surgical resection for the treatment of hepatocellular carcinoma (HCC). This study aimed to evaluate recurrence rate and risk factor of recurrence after RFA combined with TACE for early stage HCC.

Methods

We reviewed the medical records of the patients who were diagnosed with early stage HCC between March 2006 and August 2008 at Korea University Medical Center and treated with RFA combined with TACE for curative intent (n?=?65).

Results

Recurrence rate was 40% (26 cases) and the time to recurrence was 14.9?months. Cumulative recurrence rate at 1?year was 20% (13 cases) and at 2?years was 33.8% (22 cases). Significant variables for recurrence were: (1) RFA repeated more than one session at initial therapy (P?<?0.001) and (2) size of main lesion ??2?cm (P?=?0.047).

Conclusions

The recurrence rate of combination therapy was considerably high. Regardless of the therapy used, careful post-RFA follow-up is needed, especially if additional treatment is required after the first session or if the main lesion is ??2?cm at the time of RFA.  相似文献   
976.
Seo JM  Lee SJ  Kim SH  Park CK  Ha SY 《Clinical radiology》2012,67(4):329-333
Hepatocellular adenoma (HCA) is a rare, benign proliferation of hepatocytes that occurs mostly in a normal liver and in extreme rare cases, occurs in a cirrhotic liver. Hepatocellular carcinomas (HCC) arising within HCA through malignant transformation is rare. The specific incidence and mechanism of malignant transformation has not been established, but the long term use of oral contraceptives is considered a causative agent. We report a case of HCC arising from HCA detected in a hepatitis B-related cirrhotic liver with serial radiologic images.  相似文献   
977.
KJ Lim  DY Yoon  EJ Yun  YL Seo  S Baek  DH Gu  SJ Yoon  A Han  YJ Ku  SS Kim 《Radiology》2012,264(3):796-802
Purpose: To determine the characteristics and trends of the original articles published in two major American radiology journals, AJR American Journal of Roentgenology (AJR) and Radiology, between 2001 and 2010. Materials and Methods: This was a retrospective bibliometric analysis that did not involve human subjects and was exempt from institutional review board approval. All 6542 original articles published in AJR and Radiology between 2001 and 2010 were evaluated. The following information was abstracted from each article: radiologic subspecialty, radiologic technique used, type of research, sample size, study design, statistical analysis, study outcome, declared funding, number of authors, affiliation of the first author, and country of the first author. In addition, all the variables examined were presented along with the trend over time. Results: The most common subspecialty of study was abdominal (1219 of 6542, 18.6%), followed by vascular/interventional (804 of 6542, 12.3%). A total of 3744 (57.2%) original articles used magnetic resonance (MR) imaging or computed tomography (CT), 5495 (84.1%) were clinical research articles, 3060 (46.8%) had sample size of more than 50, 4087 (62.5%) were retrospective, 4714 (72.1%) performed statistical analysis, 6225 (95.2%) showed positive study outcome, 4784 (73.1%) were not funded, 3942 (60.3%) had four to seven authors, and 5731 (87.6%) were written by the primary author who was from a department of radiology or radiology-related specialties. The United States published 45.5% (2975 of 6542) of the articles, followed by Japan (n = 525, 8.0%), Germany (n = 485, 7.4%), and South Korea (n = 455, 7.0%). In the time trend analysis, the following variables showed a significantly positive trend: cardiac subspecialty, CT and MR imaging as the radiologic techniques, type of research as other (nonbasic, nonclinical), sample size of more than 50, four to seven as the number of authors, medicine-related department of the first author, and South Korea and Italy as countries of the first author. On the other hand, pediatric subspecialty, combined (basic and clinical) type of research, and number of authors fewer than four showed a significantly negative trend. Conclusion: The bibliometric analysis of the AJR and Radiology journals with articles published between 2001 and 2010 revealed characteristics and trends of the current radiology research that may provide useful information to researchers and editorial staff in radiology. ? RSNA, 2012.  相似文献   
978.
Several studies have shown higher frequencies of radiological abnormalities among gymnasts. Recently, the gene encoding the α1 chain of type XI collagen, (COL11A1) (rs 1676486), was associated with lumbar disc herniation in the Japanese population. We hypothesized that there was a significant relationship between abnormal magnetic resonance imaging (MRI) findings of the lumbar spine and the COL11A1 4603C/T gene polymorphism in collegiate gymnasts. Our study participants included 103 Japanese collegiate gymnasts (70 men and 33 women). Radiological abnormalities were evaluated using T1- and T2-weighted MRI. Genotyping for COL11A1 was performed for all the participants. By using logistic regression analysis, we observed significant associations between limbus vertebra and age (adjusted odds ratio=0.51, 95% confidence interval: 0.27-0.96), sporting experience (adjusted odds ratio=1.49, 95% confidence interval: 1.14-1.94), and a TT genotype (adjusted odds ratio=7.83, 95% confidence interval: 1.33-46.03). We conclude that a TT genotype of COL11A1 polymorphism may be a significant risk factor for limbus vertebra in Japanese collegiate gymnasts.  相似文献   
979.
980.
The objective of this study was to evaluate the effect of a healthy school tuck shop program, developed as a way of creating a healthy and nutritional school environment, on students'' access to healthy foods. Five middle schools and four high schools (775 students) participated in the healthy school tuck shop program, and nine schools (1,282 students) were selected as the control group. The intervention program included restriction of unhealthy foods sold in tuck shops, provision of various fruits, and indirect nutritional education with promotion of healthy food products. The program evaluation involved the examination of students'' purchase and intake patterns of healthy foods, satisfaction with the available foodstuffs, and utilization of and satisfaction with nutritional educational resources. Our results indicated that among of the students who utilized the tuck shop, about 40% purchased fruit products, showing that availability of healthy foods in the tuck shop increased the accessibility of healthy foods for students. Overall food purchase and intake patterns did not significantly change during the intervention period. However, students from the intervention schools reported higher satisfaction with the healthy food products sold in the tuck shop than did those from the control schools (all P < 0.001), and they were highly satisfied with the educational resources provided to them. In conclusion, the healthy school tuck shop program had a positive effect on the accessibility of healthy food. The findings suggest that a healthy school tuck shop may be an effective environmental strategy for promoting students'' access to healthy foods.  相似文献   
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