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31.
We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20‐year‐old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X‐ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation.  相似文献   
32.
A 25-year-old female has had brown to erythematous telangiectatic patches and grouped papules on her face, neck, arm, and trunk since childhood following B.C.G. vaccination. Histopathologically, the lesions consisted of hyperkeratosis, slight acanthosis, tuberculoid granulomas with some Langerhans type giant cells in the mid-dermis. Although various forms of cutaneous tuberculosis after B.C.G. vaccination have been reported, it was difficult for us to assign the patient's skin lesion to any specific disease entity. Remission of her cutaneous lesions occurred clinically and histopathologically after treatment with isoniazid and rifampin.  相似文献   
33.
Although adenocarcinoma is a well known complication of chronic inflammatory bowel disease, primary gastrointestinal lymphoma occurring in Crohn's disease is rare. A 40-year-old man with 10 year-history of Crohn's disease had multiple longitudinal ulcerative lesions on descending colon in follow-up colonoscopic examination. Microscopic examination of proximal descending colon revealed peripheral T cell lymphoma and other site of the descending colon was consistent with Crohn's disease. The patient reached complete remission of malignant lymphoma after three cycles of combined chemotherapy. He has been well for 10 months with sulfasalazine maintenance therapy but was admitted to the hospital due to spontaneous bowel perforation of ascending colon. Right hemicolectomy was done, but the patient died of post-surgical recurrent mesenteric abscess and sepsis. To the best of our knowledge, this is the first case of Non-Hodgkin's lymphoma complicating Crohn's disease in Korea which was confirmed by immunohistochemical studies.  相似文献   
34.
During liver transplantation for hepatocellular carcinoma (HCC) patients, HCC could theoretically be introduced into the systemic circulation when salvaged blood is used with an autotransfusion device. Several reports have shown that some types of leukocyte depletion filters (LDFs) could completely reduce the risk for reintroducing some types of tumor cells. In this study, we tested the ability of the LDF (RCEZ1T, Pall Biomedical Co, NY, USA) to reduce the risk for reintroducing HCC cells in vitro by using a very sensitive detection method. We divided the test group into 6 groups: group I was 10 cells, group II was 20 cells, group III was 2 x 10(3) cells, group IV was 2 x 10(5) cells, group V was 2 x 10(6) cells, and group VI was 2 x 10(7) cells. The counted cells in 200 mL saline were passed through the RCEZ1T using the force of gravity. To identify the presence of cells, the pellet was resuspended, and polymerase chain reaction (PCR) was performed. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a housekeeping gene, was used as a primer. In groups I and II, the HCC cells were completely filtered in all experiments. However, in groups III, IV, and V, the HCC cells were not completely filtered in a few of the repeated experiments, with the unfiltered rate of tumor cells being between 8% and 20%. In group VI, the HCC cells were not completely filtered in all the repeated experiments. In conclusion, the RCEZ1T filter markedly reduced the risk for reintroduction of HCC cells. However, at high HCC cell load the filter cannot completely remove all the tumor cells. Further studies are required to assess the impact in clinical settings.  相似文献   
35.
Increased expression of the sodium iodide symporter (NIS) is required for effective radioiodine treatment and reporter gene imaging of breast cancer. We investigated the effect of retinoic acid on adenovirus-mediated expression of the human NIS gene in the MCF-7 breast cancer cell line. METHODS: The MCF-7 cell line was infected with recombinant adenovirus carrying the human NIS gene (Rad-NIS). Levels of NIS messenger RNA (mRNA) and protein expression and radioiodine ((125)I) uptake were measured to evaluate adenovirus-mediated NIS gene expression in wild-type and Rad-NIS-infected MCF-7 cells after treatment with all-trans-retinoic acid (ATRA; 10(-8)-10(-6) mol/L). RESULTS: The transduction efficiency of adenovirus in MCF-7 cells at a multiplicity of infection (MOI) of 50 was >60%. After incubation with 10(-6) mol/L ATRA, the mRNA level in Rad-NIS-infected MCF-7 cells increased to 118.5 times that of wild-type MCF-7 cells, whereas the mRNA level in wild-type MCF-7 cells showed only a 2.1-fold increase. Western blot, immunocytochemical staining, and flow cytometry analyses showed that NIS protein expression in MCF-7 cells infected with Rad-NIS increased after ATRA treatment. With ATRA treatment, the amount of (125)I uptake increased in a dose-dependent manner (P < 0.001). The (125)I uptake in wild-type MCF-7 cells increased 3.1-, 5.5-, and 7.6-fold with treatment with 10(-8), 10(-7), and 10(-6) mol/L ATRA, respectively. Rad-NIS-infected cells showed a 4.0-fold increase in (125)I uptake. Treatment of Rad-NIS-infected cells with 10(-8), 10(-7), and 10(-6) mol/L ATRA increased (125)I uptake by 4.9-, 8.2-, and 27.6-fold, respectively, compared with wild-type MCF-7 cells. The level of NIS expression in Rad-NIS-infected MCF-7 cells treated with 10(-6) mol/L ATRA (245.0 +/- 13.7 pmol/10(6) cells) was much greater than the sum of the expression levels seen in ATRA-treated wild-type cells and Rad-NIS-infected wild-type cells. CONCLUSION: Retinoic acid increases adenovirus-mediated NIS expression in MCF-7 cells. Our results indicate that improved efficiency of NIS gene therapy or reporter imaging in breast cancer may be possible with retinoic acid treatment.  相似文献   
36.
We developed a technique of translocation of the pulmonary artery anterior to the ascending aorta without transection of the aorta in the repair of tetralogy of Fallot with absent pulmonary valve. Our technique includes detachment of the main pulmonary artery (MPA) from the pulmonary annulus, vertical division of the MPA, anterior translocation of the pulmonary artery with patch augmentation between the vertically divided MPA.  相似文献   
37.
Performance measurement of the microPET focus 120 scanner.   总被引:6,自引:0,他引:6  
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals.  相似文献   
38.
We report here our 10-year experience of a biopsy performed at day 14 after transplantation in 304 patients with stable graft function. The factors that may have influenced subclinical rejection were analyzed according to histology. The incidence of subclinical rejection was 13.2%. Addition of mycophenolate mofetile (MMF) as a primary immunosuppressant significantly decreased the incidence of subclinical rejection compared with patients without such treatment (odds ratio, 0.23; p < 0.05). On the other hand, HLA-DR antigen mismatch (odds ratio, 2.39) and unrelated donor (odds ratio, 2.10) were also significantly associated with decreased subclinical rejection (p < 0.05). The incidence of acute rejection in patients with normal findings was lower than in those with borderline changes or subclinical rejection (0.23 +/- 0.05 vs. 0.48 +/- 0.07 and 0.60 +/- 0.11, respectively; p < 0.05). The graft survival rates in patients with subclinical rejection were lower than in patients with normal or borderline changes at 1 (88.4% vs. 97.9% and 99.1%; p < 0.05), 5 (77.8% vs. 96.2% and 95.9%; p < 0.05) and 10 (62.3% vs. 96.2% and 93.7%; p < 0.05) years. Thus, a protocol biopsy performed on day 14 after transplantation is useful for predicting graft survival. Triple therapy including MMF, related donor and HLA-DR antigen match are important factors for reducing subclinical rejection in living-donor renal transplantation.  相似文献   
39.
40.
Two triterpenes 1 and 2 with antiviral activity againstHerpes simplex virus type 1in vitro were isolated fromPrunella vulgaris. Each compound caused a significant reduction in viral cytopathic effect whenvero cells were exposed to them for 72 hours after viral challenge. They were identified asbetulinic acid(1) and 2α, 3α-dihydroxyurs-12-en-28-oic acid(2) on the basis of their spectroscopic properties. The antiviral activity of them was estimated as EC50=30 μg/ml(1) and 8 μg/ml(2), respectively by plaque reduction assay.  相似文献   
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