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41.
The aim of this study was to evaluate the clinical usefulness of attenuation and scatter correction (AC, SC) on a 201Tl myocardial single-photon emission computed tomography (201Tl SPECT) as a multi-center trial. With a dual-detecter and a triple-detector SPECT systems with a 99mTc transmission source, simultaneous transmission/emission tomography (TCT/ECT) was performed on 38 patients with angiographically coronary heart disease (CHD) and 26 patients without evidence of CHD. Stress and delayed attenuation and scatter corrected images (SAC) and uncorrected images (NC) were reconstructed. On NC images of normal cases, influence of attenuation was greater in male than female. In comparison of 201Tl distribution between male and female, significant decrease in 201Tl activity was observed in the inferoposterior wall in male and that was observed in the anterobasal wall of the left myocardium in female. Such a difference in 201Tl distribution between male and female disappeared on SAC images. On the diagnostic performance for the identification of CHD, SAC images demonstrated improved specificity and accuracy values in the right coronary arterial territory (RCA) with visual analysis statistically. Sensitivity value in the RCA was also improved, but it was not statistically significant. Sensitivity value in the left circumflex arterial territory (LCX) increased without decrease in specificity value on SAC images. In the left anterior descending arterial territory (LAD), sensitivity value increased on SAC images. Although specificity value decreased on SAC images in LAD territory, it was not statistically significant. The difference in 201Tl distribution between male and female is improved in normal cases by attenuation and scatter correction on 201Tl myocardial SPECT. Diagnostic performance of CHD is also improved by attenuation and scatter correction, especially in territories of which specificity in assessing the absence of disease have been suboptimal. In conclusion, attenuation and scatter correction on 201Tl myocardial SPECT is considered to be clinically useful.  相似文献   
42.
We report two cases of osteoblastoma, one of them an unusual case in a 32-year-old woman in whom a maxillary tumor was confidently diagnosed as an osteoblastoma at the time of primary excision and subsequently transformed into an osteosarcoma 7 years after the onset of clinical symptoms. The other patient developed osteosarcoma arising in the maxilla, which was diagnosed 3 years after the primary excision and is very suggestive of malignant transformation in osteoblastoma. We present the radiological features, including computed tomographic and magnetic resonance imaging studies, of this unusual event of transformed tumor and compare imaging features of benign and dedifferentiated counterparts of this rare tumor complex.Members of the Group for the Image Diagnosis of Craniofacial Disorders  相似文献   
43.

Background  

BRCA1 and BRCA2 are two major tumor suppressor genes for hereditary breast and ovarian cancer. In sporadic breast cancer, although somatic mutations of these genes are rare, loss of heterozygosity (LOH) at BRCA1 and BRCA2 loci is common.  相似文献   
44.

Purpose

Gastrointestinal stromal tumors (GISTs) should be surgically resected, even those smaller than 5?cm in size, which is the threshold of clinical malignancy for submucosal tumors (SMTs) in the gastrointestinal tract. This study reviewed the use of laparoscopic surgery for gastric partial resection of GISTs or SMTs that were suspected to be GISTs.

Methods

Eighteen patients underwent laparoscopic partial resection of the stomach for GISTs or SMTs. The tumor location was confirmed by intraluminal endoscopy. One-half of the circumference around the tumor was dissected, and the tumor was turned toward the abdominal cavity. The nonresected part of the tumor and the edge of the incision line was lifted up using forceps, and the incision line was closed using laparoscopic stapling devices.

Results

Two cases were diagnosed as GIST by endoscopic biopsy. Six patients underwent endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) examinations, which diagnosed five GISTs. There were 18 tumors smaller than 5?cm, including 10 GISTs, 4 leiomyomas, 3 schwannomas, and one heterotopic pancreas.

Conclusions

Endoscopic ultrasound-guided FNAB is recommended for definite preoperative diagnosis of histopathologically unknown SMTs to determine the indications for surgery. The laparoscopic approach with the assistance of endoscopy is useful for improving the curability, with minimal invasiveness for the partial resection of GISTs.  相似文献   
45.
A 24-year-old man presented with chest pain. He was diagnosed as having a type A acute aortic dissection and an annulo-aortic aneurysm. After emergency surgery for an aortic root replacement, his electrocardiogram showed ST-segment depression and T-wave inversion. Echocardiography showed asynergy of the left ventricle without coronary ostial pathology. Heart catheterization revealed no coronary stenosis, but the true lumen of the residual ascending aorta had extreme diastolic narrowing due to flap suffocation. This resulted in coronary malperfusion. The pullback pressure curve confirmed the mechanism. The patient underwent a surgical re-intervention for a total arch repair, which diminished the coronary malperfusion. At a follow-up appointment four years and four months later, the patient was doing well.  相似文献   
46.
A hypertensive 60-year-old man presented with a rare aneurysm arising from the posterior inferior cerebellar artery (PICA) communicating artery, manifesting as subarachnoid hemorrhage with intraventricular hemorrhage. Angiography showed a small aneurysm arising from a fine and tortuous artery interconnecting the bilateral vermian branches of distal PICAs. The right PICA was absent and its vermian territory was supplied by the left PICA through this communicating artery. The right anterior inferior cerebellar artery was also connected to the vermian branch of the right PICA. At surgery, a reddish and apparent fusiform aneurysm was noted at the top of the arterial loop under the cerebellar vermis. Microsurgical trapping and removal of the aneurysm was performed without complication. Histological examination demonstrated typical findings of a true aneurysm. Only four previous cases of aneurysm of the communicating artery between the bilateral distal PICAs have been reported. In all five reported cases including ours, the PICA communicating artery contributed to the collateral blood supply of the contralateral vermian territory based on vascular anomalies. Hemodynamic stress and congenital vulnerability may have caused this aneurysm. Trapping is suitable to treat this precarious aneurysm if other collateral vessels supply the contralateral vermian territory.  相似文献   
47.
Genetic alteration in carcinoid tumors of the lung.   总被引:1,自引:0,他引:1  
Surgically resected specimens of 13 carcinoid tumors of the lung including nine typical carcinoids and four atypical carcinoids, and eight salivary gland type carcinomas (six mucoepidermoid carcinomas and two adenoid cystic carcinomas) were analyzed regarding p53 expression, loss of heterozygosity (LOH) in chromosome 3p, 9p, and K-ras mutation. The overexpression of p53 was identified in four atypical carcinoid tumors, one mucoepidermoid carcinoma, and one adenoid cystic carcinoma, however, none of typical carcinoids showed p53 immunoreactivity. LOH in 3p14 was demonstrated in three of seven informative cases in all tumors. LOH in 9p was demonstrated in two of five informative cases in all tumors. Two of three cases with LOH at 3p14 had a poor prognosis, one of which also had LOH at 9p. No mutation of the K-ras gene was observed in any of these tumors. These data thus indicate that p53 overexpression might distinguish atypical carcinoid tumors from typical tumors and might therefore be useful as an adjunct modality in the differential diagnosis of pulmonary carcinoid tumors. The presence of LOH at 3p14 or 9p may thus help to identify lung cancer patients with a poor prognosis.  相似文献   
48.
Postoperative empyema and aspergillosis were diagnosed in a 66-year-old man. Since non-operative therapy was not effective, we performed surgery. On the 8th postoperative day, a covered Ultraflex expandable stent (Boston Scientific, Galway, Ireland) was implanted to make a one-way airway for blocking a major air leak from a bronchopleural fistula causing respiratory distress. His general condition improved gradually, and he was discharged 30 days after stenting. In conclusion, we used a covered Ultraflex expandable stent to make an airway to block an air leak. This may be a new application for this stent.  相似文献   
49.

Background

The meniscus plays an important role in controlling the complex biomechanics of the knee. Meniscus injury is common in the knee joint. The perimeniscal capillary plexus supplies the outer meniscus, whereas the inner meniscus is composed of avascular tissue. Angiogenesis factors, such as vascular endothelial growth factor (VEGF), have important roles in promoting vascularization of various tissues. VEGF-mediated neovascularization is beneficial to the healing of injured tissues. However, the distribution and angiogenic role of VEGF remains unclear in the meniscus and injured meniscus. We hypothesized that VEGF could affect meniscus cells and modulate the meniscus healing process.

Methods

Menisci were obtained from total knee arthroplasty patients. Meniscal injury was created ex vivo by a microsurgical blade. VEGF mRNA and protein expression were detected by the polymerase chain reaction and immunohistochemical analyses, respectively.

Results

In native meniscal tissue, the expression of VEGF and HIF-1α mRNAs could not be detected. However, VEGF and HIF-1α mRNAs were found in cultured meniscal cells (VEGF: outer > inner; HIF-1α: outer = inner). Injury increased mRNA levels of both VEGF and HIF-1α, with the increase being greatest in the outer area. Immunohistochemical analyses revealed that VEGF protein was detected mainly in the outer region and around injured areas of the meniscus. However, VEGF concentrations were similar between inner and outer menisci-derived media.

Conclusions

This study demonstrated that both the inner and outer regions of the meniscus contained VEGF. HIF-1α expression and VEGF deposition were high in injured meniscal tissue. Our results suggest that injury stimulates the expression of HIF-1α and VEGF that may be preserved in the extracellular matrix as the healing stimulator of damaged meniscus, especially in the outer meniscus.  相似文献   
50.
Purpose  Patient-controlled epidural analgesia (PCEA) was developed for use after surgery for thoracic esophageal cancer to relieve wound pain, introduce early rehabilitation, and provide an uneventful postoperative recovery. Methods  This retrospective study investigated 22 patients who underwent esophageal surgery to determine the efficacy of postoperative management with PCEA. In the PCEA group (n = 12), patients had two epidural catheters inserted to cover both the thoracic and abdominal incision with a patient-controlled bolus capability. Results  Postoperative mechanical ventilation was administered in all cases in the control group (n = 10). On the other hand, this was only necessary in two patients in the PCEA group. The amount of time the patients stayed in the intensive care unit and the hospital was significantly shorter in the PCEA group than in the control group (P < 0.001 and P < 0.01, respectively). Respiratory complications occurred in four patients in the control group, and none in the PCEA group. The mean number of supplemental analgesics administered for breakthrough pain until the 7th postoperative day was 5.5 in the control group, and 1.3 in the PCEA group (P < 0.001). Conclusions  Early rehabilitation is facilitated with intensive PCEA, while it also improves postoperative management and reduces hospitalization after esophageal surgery.  相似文献   
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