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91.
BACKGROUND AND PURPOSE: To analyze the interfractional set-up errors and intrafractional organ motions and to define appropriate planning target volume (PTV)- and planning organs at risk volume (PRV)-margins in intensity-modulated radiotherapy (IMRT) for head and neck tumors. PATIENTS AND METHODS: Twenty-two patients with head and neck or brain tumors who were treated with IMRT were enrolled. The set-up errors were defined as the displacements of the coordinates of bony landmarks on the beam films from those on the simulation films. The organ motions were determined as the displacements of the coordinates of the landmarks on the images recorded every 3 min for 15 min on the X-ray simulator from those on the initial image. RESULTS: The standard deviations (SDs) of the systematic set-up errors (Sigma-INTER) and organ motions (Sigma-intra) distributed with a range of 0.7-1.3 and 0.2-0.8 mm, respectively. The average of the SDs of the random set-up errors (sigma-INTER) and organ motions (sigma-intra) ranged from 0.7 to 1.6 mm and from 0.3 to 0.6 mm, respectively. Appropriate PTV-margins and PRV-margins for all the landmarks ranged from 2.0 to 3.6 mm and from 1.8 to 2.4 mm, respectively. CONCLUSIONS: We have adopted a PTV-margin of 5mm and a PRV-margin of 3mm for head and neck IMRT at our department.  相似文献   
92.
93.
To improve the prognosis after hepatectomy for HCC, repeated postoperative transcatheter arterial infusions of anticancer drugs and lipiodol (TAI) were given. TAI may be effective as an adjuvant therapy for prevention of residual liver recurrence after hepatectomy, probably by suppression of the development of intrahepatic micrometastases rather than of multicentric carcinogenesis.  相似文献   
94.
We report a case of abdominal wall abscess caused by diverticulitis of the jejunum penetrating through the abdominal wall. A 53-year-old Japanese woman visited a local hospital complaining of abdominal pain and a mass in the left lower abdomen. An abdominal computed tomography scan showed a tumor with isodensity in the left lower abdominal wall. Magnetic resonance imaging showed a mass in the abdominal wall with isointensity in the T1-intensified image and high intensity in the T2-intensified images. The mass was heterogeneous inside and protruded partially toward the intraperitoneal cavity. Ultrasound examination showed a heteroechoic mass extending into the intraperitoneal cavity. Laparotomy revealed a tumor in the abdominal wall with a fistulous tract extending to the jejunum. We resected the abdominal wall tumor with partial resection of the small intestine. The resected specimen contained a tumor with a fistulous tract passing through the abdominal wall. Histological examination revealed remarkable infiltration of neutrophils and a bacterial mass in the abdominal wall tumor, with a fistulous tract connected to the area adjacent to the mesenteric border of the jejunum. These findings suggested that diverticulitis of the jejunum had penetrated through the abdominal wall, leading to the formation of an abscess. We report this case to highlight the need for complete gastrointestinal evaluation with gastrointestinal barium studies and imaging analysis to examine extension of intra-abdominal lesions in patients with an unexplained abdominal wall abscess.  相似文献   
95.
OBJECT: Clinical application of the convection-enhanced delivery (CED) technique is currently limited by low infusion speed and reflux of the delivered agent. The authors developed and evaluated a new step-design cannula to overcome present limitations and to introduce a rapid, reflux-free CED method for future clinical trials. METHODS: The CED of 0.4% trypan blue dye was performed in agarose gel to test cannula needles for distribution and reflux. Infusion rates ranging from 0.5 to 50 microl/minute were used. Agarose gel findings were translated into a study in rats and then in cynomolgus monkeys (Macacafascicularis) by using trypan blue and liposomes to confirm the efficacy of the reflux-free step-design cannula in vivo. Results of agarose gel studies showed reflux-free infusion with high flow rates using the step-design cannula. Data from the study in rats confirmed the agarose gel findings and also revealed increasing tissue damage at a flow rate above 5-microl/minute. Robust reflux-free delivery and distribution of liposomes was achieved using the step-design cannula in brains in both rats and nonhuman primates. CONCLUSIONS: The authors developed a new step-design cannula for CED that effectively prevents reflux in vivo and maximizes the distribution of agents delivered in the brain. Data in the present study show reflux-free infusion with a constant volume of distribution in the rat brain over a broad range of flow rates. Reflux-free delivery of liposomes into nonhuman primate brain was also established using the cannula. This step-design cannula may allow reflux-free distribution and shorten the duration of infusion in future clinical applications of CED in humans.  相似文献   
96.
Presented herein is a case of combined small cell and squamous cell carcinoma in a polypoid bronchial tumor, showing a histologically unique progression, in a 76-year-old Japanese man. A bronchofiberscopic examination revealed that the bronchus (left B3) was occluded by the polypoid tumor. Biopsies were performed, and the pathological diagnosis was poorly differentiated squamous cell carcinoma. The patient consequently underwent a left upper lung lobectomy. The surgical specimen was described as a 24 x 8 x 8 mm soft tumor, emanating from the bronchial wall (left B3). Histologically, the tumor had two distinct components: (i) nearly the entire tumor was composed of atypical small round cells, with a high nuclear-cytoplasmic ratio, in the lamina propria, under the basement membrane; and (ii) the surface of the tumor was composed of poorly differentiated squamous cell carcinoma that had proliferated primarily above the basement membrane but there was also some proliferation, seen as island-like formations, below the basement membrane. The histological diagnosis was combined small cell and squamous cell carcinoma. It was suspected that poorly differentiated squamous cell carcinoma, generated in the bronchial epithelium, had caused small cell carcinoma resulting from neuroendocrine differentiation during its invasion into the lamina propria.  相似文献   
97.
Exophytic giant cavernous hemangioma of the liver with growing tendency   总被引:1,自引:0,他引:1  
Hepatic hemangioma is a common benign tumor, but its exophytic and expansile forms may be atypical. We report a case of exophytic hemangioma of the liver with a growing tendency, demonstrated using magnetic resonance imaging (MRI) and computed tomography (CT) combined with angiography.  相似文献   
98.
TIN (ifosfamide 1.5 g/m2 daily for 3 days, paclitaxel 175 mg/m2, and nedaplatin 70 mg/m2 on day 1) was administered to patients with metastatic urothelial cancer previously treated by platinum-based chemotherapy and repeated every 4 weeks. Four patients received maintenance therapy, which consisted of 5'-DFUR 800 mg/day orally for 12 weeks and 1 subsequent course of TIN. This therapy regimen was repeated for 2 years from initiation of TIN. Eleven of 12 patients (91.6%) demonstrated a major response (3 complete responses, 8 partial responses), with durations of response ranging from 3 to 20 months. Progression-free survival time was from 0 to 20 months (median 8 months). One-year progression-free survival rate was 45.8%. Overall survival time was from 2 to 20 months (median 10.5 months). One-year overall survival rate was 53.5%. Grade 3/4 hematologic toxicity involved neutropenia in 100% and thrombocytopenia in 33.3%. Febrile neutropenia was observed in 5 patients (41.6%). Grade 3 nonhematologic toxicity involved malaise in 15.3%. No patient discontinued this therapy because of complications. TIN is a potent, well-tolerated regimen for previously treated patients with urothelial cancer.  相似文献   
99.
Thallium (Tl)-201 single-photon emission computed tomography (SPECT) is a useful tool for detecting brain tumors. In this study, we evaluated the utility of Tl-201 SPECT for determining the effect of maintenance chemotherapy with ACNU (nimustine hydrochloride)/VCR (vincristine sulfate) against malignant gliomas. The cases were comprised of 16 glioma cases; 6 astrocytomas, 2 anaplastic astrocytomas, and 8 glioblastomas. We first analyzed the correlation between Tl-201 uptake ratio and proliferative activity of the tumor, using Ki-67 immunohistochemistry in 13 cases of glioma. The uptake ratio of Tl-201 correlated with the Ki-67 staining indices (SI), and a closer correlation was obtained using Tl-201 delayed images than with the early images. We also analyzed the chronological changes of Tl-201 uptake ratio and volume of abnormal area evaluated by MRI T2-weighted imaging (MRI T2WI), in 10 cases of malignant glioma during maintenance chemotherapy. The Tl-201 uptake ratio gradually decreased with the effect of maintenance chemotherapy, and the sensitivity was superior to MRI findings. Together with MRI, Tl-201 SPECT is considered to be a useful indicator for evaluating the effect of maintenance chemotherapy against malignant gliomas.  相似文献   
100.
This article provides an overview of the use of human materials and information (human subject) in the new phase of pharmacological research and development in the current context, especially as it relates to the progress of the human genome project. In a sense, humanity has been drastically reduced to an array of DNA sequences that can be universally used in comparing living things. Pharmacological studies now acquire a unique status in bridging chemical substances to human body function. To perform the full activity of the nature of pharmacology, it requires both genotype and personal information, i.e. medical records and life style information, as research resources. In the UK, the Medical Research Council, the Wellcome Trust, and the Department of Health had started to plan UK Biobank for promoting and supporting the new stage of medical and pharmacological research and development. UK Biobank will collect DNA samples, medical records, and life style information of 500,000 people between the age range of 45 to 69 years old. It will follow the changes in health status of the participants for more than 10 years. The Biobank will provide researchers chances to correlate the genotypic traits to phenotypic ones, i.e. common diseases. In relation to the secondary use of medical records in health research, National Health Service (NHS) initiated a new strategy on the governance of patient information. These movements clearly demonstrated the indispensable nature of infrastructures for promoting and supporting pharmacological and medical research. We discuss on the necessary policies in constructing the Japanese infrastructure.  相似文献   
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