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991.
Diagnosis of deep vein thrombosis using multi-detector helical CT   总被引:1,自引:0,他引:1  
PURPOSE: To evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). Materials and Methods: The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. RESULTS: Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5 +/- 7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. CONCLUSION: MDHCT for the diangosis of DVT has the advantages of wider scanning range, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities.  相似文献   
992.
This report describes a case of bone involvement by epithelioid sarcoma, which on imaging had the appearance of a primary intraosseous lesion of the scapula. The tumor initially presented as a subcutaneous nodule which was mistakenly diagnosed as "fibrosis" following initial resection. The lesion recurred locally and after several resections presented with several ulcerated subcutaneous nodules, at which time all imaging studies were performed. The patient was treated with en bloc upper humeral interscapulothoracic resection and shoulder reconstruction. Two years after the operation the patient is alive without local recurrence or metastasis.  相似文献   
993.
Although one-dimensional densitometry has been widely performed for linac dosimetry, it is a time-consuming, labor-intensive procedure. We studied a new densitometry system (DD-System) that consists of a personal computer and common flatbed-type scanner, with regard to its usefulness for daily QC checks in comparison with conventional densitometry. The spatial resolution of the DD-System is very high, and its accuracy of measurements of field size and flatness are equivalent to those of a conventional system at an optical density <2.0. Although the performance of the image scanner limits the maximum optical density of our system, this system can acquire high-resolution two-dimensional dose distributions quickly and easily. In conclusion, the DD-System is very useful for reducing the amount of time and effort required in daily QC activities. We consider this system applicable to the analysis of complicated dose distributions in this era of IMRT.  相似文献   
994.
Liver tumors, especially hepatocellular carcinomas (HCCs), often exhibit no contrast with surrounding non-tumorous liver tissue in F-18-fluoro-2-deoxy-2-fluoro-D-glucose (FDG) positron emission tomography (PET) images obtained at the usual interval of one hour after intravenous FDG injection. We evaluated the usefulness of FDG PET studies of liver tumors performed 2 hours after intravenous injection. METHODS AND MATERIALS: Fifteen pretherapeutic patients with 33 liver tumors were studied, including 11 patients with 18 HCCs, and 4 patients with 15 metastatic liver tumors (METAs) from 3 colorectal carcinomas and 1 esophageal carcinoma. After transmission scans, emission scans were obtained 45-55 minutes and 115-125 minutes after intravenous injection of 185-370 MBq FDG as early images and delayed FDG PET images, respectively. Visual analysis of early and delayed images was performed, and the FDG uptake in the tumor to that in nontumorous liver ratio (T/N ratio), the FDG uptake in tumor to that in soft-tissue ratio (T/S ratio) and the FDG uptake in non-tumorous liver to that in soft-tissue ratio (N/S ratio) were calculated for each image. RESULTS: In visual analysis, visual improvement seen in images was observed in 6 of 18 HCC lesions and all 15 META lesions. In quantitative analysis, the mean T/S ratio and T/N ratio of HCCs in early images were 4.97 and 1.90, respectively, and those in delayed images were 6.24 and 2.20, respectively. The mean T/S ratio and T/N ratio of METAs in early images were 5.97 and 2.21, respectively, and those in delayed images were 6.99 and 3.80, respectively. The T/S ratio of HCCs and T/S ratio and T/N ratio of METAs were significantly higher in delayed images than in early images. The mean N/S ratios of HCC cases were 2.58 in the early images and 2.57 in the delayed images, but the ratio showed no constant tendency in the images. All N/S ratios of META cases were decreased in delayed images, although the significance of the difference between early and delayed images in N/S ratios was not analyzed because of the small number of cases. CONCLUSION: FDG PET studies performed 2 hours after intravenous injection were useful for clear visualization of liver tumors, especially metastatic liver tumors.  相似文献   
995.
PURPOSE: The purpose of this study was to determine the physiological responses of elderly women to a well-rounded exercise program performed in water (WEX). METHODS: The participants (60-75 yr of age) were randomly divided into a training (TR) group (N = 15) and a control group (N = 15). The TR group participated in a 12-wk supervised WEX program, 70 min x day(-1), 3 d x wk(-1). The WEX consisted of 20 min of warm-up and stretching exercise, 10 min of resistance exercise, 30 min of endurance-type exercise (walking and dancing), and 10 min of cool-down exercise. RESULTS: The WEX led to an increase (P < 0.05) in peak VO2 (12%) and VO2 at lactate threshold (20%). Muscular strength evaluated by a hydraulic resistance machine increased significantly at resistance dial setting 8 (slow) for knee extension (8%), knee flexion (13%), chest press (7%) and pull (11%), shoulder press (4%) and pull (6%), and back extension (6%). Vertical jump (9%), side-stepping agility (22%), trunk extension (11%), and FEV1.0 (7%) also increased significantly. There was a significant decrease in skin-fold thickness (-8%), low-density lipoprotein (LDL) cholesterol (-17%), and total cholesterol (-11%). There were no significant changes in these variables in the control group. CONCLUSION: These results indicate that WEX elicits significant improvements in cardiorespiratory fitness, muscular strength, body fat, and total cholesterol in older adult women. Water-based exercise appears to be a very safe and beneficial mode of exercise that can be performed as part of a well-rounded exercise program.  相似文献   
996.
CyberKnife stereotactic irradiation for metastatic brain tumors   总被引:5,自引:0,他引:5  
BACKGROUND: The CyberKnife provides a new technique for performing frameless stereotactic irradiation. So far, few reports have been published on clinical outcomes obtained with the CyberKnife. This report summarizes our clinical experience with CyberKnife irradiation for metastatic brain tumors. MATERIALS AND METHODS: Seventy-seven lesions (48 patients) were evaluated and analyzed, and 66 lesions in 41 patients were treated with stereotactic radiosurgery (SRS). The prescribed dose was 9 to 30 Gy. RESULTS: Freedom from progression of the tumors was more likely with a prescribed dose of at least 24 Gy than with one of less than 20 Gy (p=0.0244; log-rank test). The CR (complete response) rate was significantly higher when D99 was at least 24 Gy (p=0.0045). There were no severe side effects. CONCLUSION: Stereotactic irradiation with the CyberKnife for metastatic brain tumors is effective and safe. D99 should be at least 24 Gy for CyberKnife SRS treatment.  相似文献   
997.
Surgically implanted ports have been used in continuous or repetitive intra-arterial (IA) chemotherapeutic infusions for patients with multiple liver metastases from colorectal cancer. Recently, a percutaneous implantation procedure was developed, facilitating safe and less invasive IA infusions in the treatment of various disease conditions. This article focuses on the interventional techniques for percutaneous implantation of a vascular access device, consisting of an indwelling catheter and an implantable port, to perform IA infusions. Additionally, we describe details of the alteration of blood flow by coil-embolization that can be performed to obtain selective drug distribution to the target area and to avoid side effects caused by the administration of the chemotherapeutic agent into nontarget areas.  相似文献   
998.
To clarify the clinical significance of uterine cervical cytology during pregnancy, we analyzed the incidence of cervical cytology and its accuracy. Of the 1,593 pregnant women underwent cervical cytology, the patients with abnormal cytology were followed up and performed histological confirmation on colposcopic biopsy specimen. An incidence of abnormal cytology and cervical neoplasm during pregnancy were 1.63% (26 cases) and 0.82% (13 cases), respectively. The incidence of abnormal cytology in the pregnant women was significantly higher than that (0.9%) in mass-screened, non-pregnant 214,375 women under the age of 45 years (P < 0.001). There was no significant difference of the incidence of cervical neoplasm between in the pregnant women and in mass-screened, non-pregnant women (0.82% vs. 0.46%). The accuracy of cervical cytology during pregnancy was 45.0% and this was not significantly different from that (27.6%) in the mass-screened, non-pregnant women. Since, cervical screening cytology for uterine cervical cancer in the pregnant women as shown in this study, has an equal effectiveness to that in the mass-screened non-pregnant women, routine cervical cytology is highly recommended to performed during pregnancy. In addition, management of pregnant women with abnormal cytology was discussed in this article.  相似文献   
999.
BACKGROUND: Corticosteroids often induce steroid psychosis, a collection of heterogeneous syndromes with different pathophysiologic mechanisms. To date, no study has focused specifically on recurrent corticosteroid-induced mood disorders and considered their long-term outcome and treatment strategies. METHOD: Nine patients whose initial clinical presentation met DSM-IV criteria for a substance-induced mood disorder were identified by a review of medical records. Their clinical characteristics and treatments were examined. RESULTS: All 9 corticosteroid-treated patients had a clinical course of bipolar disorder. Seven patients initially developed a manic or hypomanic state with subacute onset ranging from 1 to 3 months. Six patients had manic episodes accompanied by psychotic features. The proportion of manic episodes relative to total mood episodes of the 9 patients was 65.6%, suggesting manic predominance. Seven patients showed mood episodes that had no direct relationship to corticosteroid therapy and were preceded by various psychosocial stressors. Four of 5 patients who received steroid pulse therapy rapidly became manic or hypomanic. Antidepressants as well as mood stabilizers were useful for treatment of the present 9 patients. CONCLUSION: Recurrent cases of corticosteroid-induced mood disorder have interesting clinical features, such as subacute onset, manic predominance, frequent accompanying psychotic features, and similar recurrent episodes in association with psychosocial stressors and corticosteroid use. Management, including psychopharmacologic intervention, should be indicated by a consideration of the underlying illnesses and psychosocial stressors.  相似文献   
1000.
Tissue plasminogen activator (tPA) is a serine protease that catalyzes the conversion of plasminogen (plg) to plasmin. The tPA-plasmin system plays a role in synaptic plasticity and remodeling. In this review, we focused on the role of tPA-plasmin system in the rewarding effect of morphine. A single morphine treatment induced tPA mRNA and protein expression in a naloxone-sensitive manner, which was associated with an increase in the enzyme activity in the nucleus accumbens (NAc). The acute effect of morphine in inducing tPA expression was diminished after repeated administration. No differences were observed in the morphine-induced antinociceptive effect between wild-type and tPA knockout (tPA-/-) mice. Morphine-induced conditioned place preference and hyperlocomotion were significantly reduced in tPA-/- and pLg-/- mice, being accompanied by a loss of morphine-induced dopamine release in the NAc. Microinjection of either exogenous tPA or plasmin into the NAc significantly potentiated morphine-induced dopamine release in the NAc of ICR mice. In contrast, plasminogen activator inhibitor-1 (PAI-1) dose-dependently reduced morphine-induced dopamine release. Furthermore, the defect of morphine-induced dopamine release and hyperlocomotion in tPA-/- mice was reversed by microinjections of either exogenous tPA or plasmin into the NAc. Our findings demonstrate a novel function of the tPA-plasmin system in regulating dopamine release in the NAc, which is involved in the morphine reward.  相似文献   
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