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871.
In vivo three-dimensional patellar tracking on the femur   总被引:3,自引:0,他引:3  
In vivo three-dimensional patellar tracking under weightbearing conditions was investigated with the principal reference axes of the femur in the coronal and axial planes, using a biplanar image-matching technique. Three-dimensional knee models of eight healthy volunteers were constructed using computed tomography scanning. Projection images of the models were fitted onto anteroposterior and lateral radiographs of the knees at hyperextension and at every 15 degrees from 0 degrees to 120 degrees flexion. Knee motion then was reconstructed on a computer. Patellar tracking during knee flexion was described simply with a medial jerk shift of 8 mm in early flexion until 30 degrees and a linear tracking with minimal mediolateral translation. The linear tracking portion was located laterally 5 mm from the mediolateral center of the femoral condyles. On average, the direction of this linear tracking was almost perpendicular to the distal condylar line in the coronal plane and perpendicular to the posterior condylar axis in the axial plane. These results help improve the understanding of patellofemoral kinematics and provide useful information for the design and positioning of the prostheses used in total knee arthroplasty.  相似文献   
872.
PURPOSE: The advent of multidetector-row computed tomography (MDCT) has enabled images with good spatial resolution to be obtained over a wide range in a short scanning time. Our purpose was to determine whether CT angiography using the MDCT system could effectively depict extracranial-intracranial (EC-IC) bypass routes. METHOD: Helical CT angiography was performed using an MDCT scanner in 12 patients who had undergone EC-IC bypass surgery: 10 patients had undergone superficial temporal artery-middle cerebral artery (MCA) anastomosis, 1 patient had undergone an encephaloduroarteriosynangiosis procedure for the treatment of moyamoya disease, and 1 patient had undergone an external carotid artery-MCA anastomosis using a graft. The resulting CT angiograms were visually evaluated for their depiction of the EC-IC bypass route. Conventional angiograms were available for comparison in all 12 patients. RESULTS: The EC-IC bypass was visualized to be patent at the site of anastomosis in all 12 patients. Branches of the MCA secondary or more to those connected to a donor artery were demonstrated in 9 patients, whereas MCA branches immediately distal to the anastomosis were demonstrated in 3 patients. The CT angiography findings corresponded well with the conventional angiography findings in all patients. CONCLUSION: Helical CT angiography using the MDCT technique is an effective method for visualizing EC-IC bypass routes.  相似文献   
873.
In otorthinolaryngology, Stenvers' method is employed in radiography of the pyramid (internal acoustic meatus and semicircular canals). However, in cases of dizziness, where the prone position is difficult to achieve, we occasionally use the opposite Stenvers' method instead of the conventional one. This makes it possible to perform radiography with the patient in the supine position. Compared with the conventional Stenvers' method, the problems of this method were increases not only in the rate of magnification but also in lens dose. In this study, we evaluated these problems by employing computed tomography (CT) and a glass dosimeter with phantom as well as by clinical evaluation. The results showed no statistically significant difference between Stenvers' method and the opposite Stenvers' method in both the rate of magnification and the clinical evaluation. The increase in lens dose with the opposite Stenvers' method was not significant. We concluded that the opposite Stenvers' method was useful.  相似文献   
874.
Left renal and left adrenal masses were incidentally found by computerized tomography (CT) in a 56-year-old man who was admitted to our hospital for treatment of upper digestive tract hemorrhage. Apparently no clinical signs suggestive of Cushing's syndrome existed. The renal tumor was diagnosed as renal cell carcinoma based on the findings on enhanced CT. 131I-adosterol uptake in the examination of adrenal scintigraphy under dexamethasone suppression was definitely increased in the left adrenal gland, although hormonal examinations of serum and urine for adrenal functions were within the normal range. Plasma adrenocorticotropic hormone (ACTH) and serum cortisol were suppressed by administration of 2 mg dexamethasone for 2 days. The left kidney was radically removed by surgery together with the left adrenal gland. Histological diagnoses were left renal cell carcinoma and adrenocortical adenoma.  相似文献   
875.
A case of renal angiomyolipoma, successfully treated with non-ischemic tumor enucleation, is reported. A 16-year-old Japanese female visited another hospital with a chief complaint of general fatigue. She was diagnosed with angiomyolipoma of the right kidney, 7 cm in the long axis, which developed exteriorly at the lower pole. A nephrectomy was recommended. The patient visited us for a second opinion. We judged that nephron-sparing surgery was applicable to this case. The patient underwent non-ischemic tumor enucleation using a microwave tissue coagulator via retroperitoneal approach. The patient was discharged from our hospital 9 days after the surgery. Since a preoperative diagnosis with renal angiomyolipoma can be obtained relatively easily, maximum efforts for nephron-sparing surgery should be made.  相似文献   
876.
The intensive stromal reaction is one of characteristics of pancreatic exocrine carcinoma. The mutual interaction between pancreatic cancer cells and orthotopic tumor-derived fibroblasts have not been clarified yet. In this study, we sought to elucidate the mechanism underlying the tumor-stromal interaction with an in vitro coculture experimental system. Considerable strong c-Met expression was detected in seven out ten lines of human pancreatic carcinoma cells, as determined by Western blotting. For hepatocyte growth factor (HGF)-production, however, none or only trace amounts of HGF could be detected in those ten cell lines. Of the two lots of tumor-derived fibroblasts obtained from two pancreatic cancer patients, the fibroblasts capable to produce HGF could initiate an apparent invasion-stimulating response in strong c-Met-expressed Suit-2 and Panc-1 cells but not in faint expressed Mia PaCa-2 and BxPC-3 cells. A specialized HGF antagonist, NK4 would effectively inhibit the fibroblast-mediated invasive growth, thus proving the key role of the paracrine-fashioned HGF/c-Met pathway in the tumor-stromal interaction. On the other hand, the regulative action of cancer cells on HGF expression of fibroblasts was also investigated using direct or indirect coculture systems. For the fibroblasts that originally did not produce HGF, cancer cells failed to show any HGF-inductive effect. For the HGF-producing fibroblasts, despite of somewhat upregulation or downregulation in fibroblast HGF expression, the feedback regulation by studied pancreatic cancer cells in both coculture modes were relatively limited. This in vitro study sketched out the interaction between cancerous and stromal compartments with an emphasis on HGF/c-Met signal pathway, thus possibly helping to unveil the more complicated mutual modulation in vivo between pancreatic cancer and host mesenchymal tissues.  相似文献   
877.
A phase I study was conducted to determine the maximum tolerated dose (MTD) and the dose limiting toxicity (DLT) of gemcitabine and irinotecan combination therapy as second line treatment in patients with advanced non-small cell lung cancer (NSCLC). Twelve patients with measurable NSCLC (age range 46-74 years; 7 males, 5 females; performance status 0 = 4, 1 = 8) who progressed or failed first-line chemotherapy were enrolled. Prior chemotherapy was platinum-based without gemcitabine or irinotecan. Gemcitabine was administered at a fixed dose of 1,000 mg/m2 after irinotecan administration, and irinotecan was administered at doses from 50 to 125 mg/m2 with an increment of 25 mg/m2, both on day 1 and 8. Chemotherapy was repeated every 3 weeks. Grade 3/4 leukopenia occurred in three patients (25%), neutropenia in four (33%), anemia in one (8%), and thrombocytopenia in one (8%). Grade 3 nausea and vomiting was observed in three (25%), grade 2 diarrhea in one (8%), and liver dysfunction in one (8%). Other toxicities were mild. Two of the three patients at level 4 (irinotecan 125 mg/m2) experienced dose limiting toxicity: one patient experienced grade 4 leukopenia and neutropenia, and the other experienced treatment delay of more than 2 weeks. The objective response rate was 16.6% (2/12). The maximum tolerated dose in this combination therapy was gemcitabine 1,000 mg/m2 and irinotecan 125 mg/m2. The dose level of gemcitabine 1,000 mg/m2 and irinotecan 100 mg/m2 on day 1 and 8 of a 3-week cycle is recommended for a phase II study.  相似文献   
878.
We describe a 57-year-old woman who underwent modified mastectomy for right breast cancer (T2N0M0) with overexpression of HER2, in whom lung metastasis developed 3 years after operation. She received sequential chemotherapy, including epirubicin plus cyclophosphamide, docetaxel, paclitaxel and trastuzumab, but the lung lesion progressed after transiently showing a partial response. Oral treatment with UFT and cyclophosphamide was begun as fifth-line treatment. The lung tumor shrank after 2 months, and a partial response has been maintained during continued treatment with UFT and cyclophosphamide. No adverse effects have occurred. We regard combination therapy with oral UFT and cyclophosphamide to be useful for the management of metastatic breast cancer, even in heavily pretreated cases with overexpression of HER2.  相似文献   
879.
880.
BACKGROUND: To identify antigens specifically recognized by the immune surveillance system in patients with hepatocellular carcinoma (HCC), the authors examined two complementary DNA (cDNA) libraries of moderately differentiated HCC by serologic analysis of recombinant cDNA expression libraries (SEREX). METHODS: The libraries were screened with autologous patients' sera, and sequences of the reacted clones were determined. To study the immunoreactivity of the antigens, sera from 20 patients with HCC, from 20 healthy volunteers, and from 16 patients with chronic viral hepatitis were examined. RESULTS: Twenty-seven antigens were identified. They included SART1, p57Kip2, ROCK-1, gamma-catenin, and heat shock proteins, which are classified as tumor-associated genes. Three of 27 antigens-Tat-binding protein-1 (TBP-1), beta4 integrin-binding protein (p27[BBP]), and ribosomal protein L30 (rpL30)-were reacted predominantly with sera from patients with HCC (55% of patients, 45% of patients, and 20% of patients, respectively). Patients in the control group had no antibodies against these three antigens. Seventy percent of patients with HCC had the antibody against at least one of these antigens. CONCLUSIONS: Disease specific humoral immune response against TBP-1, p27(BBP), and rpL30 was induced in patients with HCC, and the antibodies against these antigens also may be used as tumor markers.  相似文献   
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