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排序方式: 共有5801条查询结果,搜索用时 546 毫秒
71.
M Notani K Amano H Kawamura T Tanikawa H Kawabatake H Iseki T Shiwaku T Nagao Y Iwata T Taira 《No shinkei geka. Neurological surgery》1987,15(3):251-258
CT-guided stereotactic brachytherapy has been performed for the deep-seated malignant gliomas using the double-catheter after-loading method. The catheter system consists of two coaxial polyethylene tubes with closed tips. The outer catheter is 3.0 mm in outer diameter and 2.4 mm in inner diameter. The inner catheter is 2.0 mm in outside diameter and 1.4 mm in inside diameter, and contains the radioactive sources. Localization of the target volume is determined by the preoperative findings of computed tomography (CT), magnetic resonance imaging (MRI), and cerebral angiography. Dosimetry and dose planning are so finalized for the target volume as to be irradiated interstitially more than tumoricidal dose. After stereotactic biopsy of the deep-seated brain tumors, stereotactic implantation of the outer catheters is performed using Iseki Stereotactic System in the CT room. Burr holes had been previously opened in the operating room. The inner catheters containing nonradioactive sources (dummy sources) are inserted, and skull X-p is taken to confirm the position of the dummy sources, and to calculate the dosimetry by computer. The inner catheters are replaced with catheters containing radioactive sources (226Ra) in the irradiation room. 226Ra sources deliver at least 500 rads/day (approximately 20 rads/hr) to the target volume as interstitial irradiation. Two patients of malignant gliomas treated with this procedure were shown as representative cases. These patients underwent CT-guided stereotactic brachytherapy as "boost" combined with conventional external irradiation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
72.
Probiotics have been suggested to be effective for functional dyspepsia, but their effect on gastric motility is not clear. We evaluated the effect of Lactobacillus gasseri OLL2716 (LG21 strain) on mild to moderate delayed gastric emptying by a double-blind, parallel-group, placebo-controlled, randomized trial. Participants (n = 28) were randomly assigned to ingest LG21 strain-containing yogurt (LG21 strain group) or LG21 strain-free yogurt (placebo group) for 12 weeks. The 13C gastric emptying breath test was performed to measure the gastric emptying rate over time following ingestion of a liquid meal, and the time to reach the peak (Tmax) was used as an indicator of gastric emptying. We also measured the salivary amylase concentration, an indicator of autonomic dysfunction under stress. The per-protocol population (n = 27, male n = 4, female n = 23) was evaluated for efficacy. When a ≥30% reduction in the difference between participant’s Tmax and the Japanese mean Tmax was defined as an improvement, the odds ratio of improvement in delayed gastric emptying compared to placebo after 12 weeks was 4.1 (95% confidence interval, 0.8 to 20.2). Moreover, salivary amylase concentrations were significantly lower than in the placebo group, indicating an improvement in autonomic function. The present data were not enough to support the beneficial effects of the LG21 strain on delayed gastric emptying. However, if we define the odds ratio in further study investigated with a larger number of participants, LG21 strain might be expected to have some impact on delayed gastric emptying. 相似文献
73.
Makita Ayu Nagao Tomoaki Miyoshi Ken-ichi Koizumi Yohei Kurata Mie Kondo Fumikazu Shichijo Satoru Hirooka Masashi Yamaguchi Osamu 《Clinical and experimental nephrology》2021,25(9):981-987
Clinical and Experimental Nephrology - The progression of chronic kidney disease (CKD) depends on the extent of fibrosis in the kidneys; however, a renal biopsy is necessary to evaluate the... 相似文献
74.
Photoreceptor differentiation of retinoblastoma: An electron microscopic study of 29 retinoblastomas
Yasuo Tajima Shigeru Munakata Yasuo Ishida Tohru Nakajima Isamu Sugano Koichi Nagao Kensei Minoda Yoichiro Kondo 《Pathology international》1994,44(12):837-843
Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photo-receptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas. 相似文献
75.
Wei-dong Zhang Masataka Nagao Takehiko Takatori Kimiharu Iwadate Yoshiyuki Itakura Yoshihiro Yamada Hirotaro Iwase Tsuneaki Oono 《International journal of legal medicine》1995,107(4):174-178
This paper investigates the immunohistochemical dynamics of leukotoxin (9,10-epoxy-12-octadecenoic acid, LTx) in the lungs of rats exposed to hyperoxia with or without paraquat. The rats were treated with 100% oxygen or ambient air for 24. 48, 72 and 96 h in the presence or absence of a low or high dose paraquat (1,1-di-methyl-4,4-bipyridinium, PQ) injection. Immunostaining for LTx demonstrated positive reactions in the neutrophils that showed a progressive increase in intensity of staining with time in all groups exposed to 100% oxygen and in the group with high dose PQ, but the positive findings were weak in the group injected with low dose PQ only. We found the positive immunostaining reaction not only in neutrophils but also in alveolar macrophages. This indicates that LTx is produced by alveolar macrophages as well as by neutrophils depending on the treatment period under hyperoxic conditions, suggesting that LTx is an important chemical mediator in pulmonary diseases. 相似文献
76.
Jun Nawata Yasunori Toyoda Hirokazu Nisihira Kohjiro Honda Hisato Kigasawa Takeshi Nagao 《European journal of pediatrics》1994,153(5):325-327
A 6-year-old girl with post-hepatitic severe aplastic anaemia was referred to our hospital. Haematological examination showed a haemoglobin level of 5.2 g/dl, platelet count of 8,000/l, and white blood cell count of 130/l with 17% neutrophils. She was treated with recombinant human granulocytecolony stimulating factor (15 g/kg/day i.v.) and cyclosporin A (6 mg/kg/day p.o.). The absolute neutrophil count gradually increased, but Hb and platelets were not improved. The intravenous administration of recombinant human erythropoietin (100 U/kg three times a week) was started, and the reticulocyte count reached 20000/l on day 12. The platelets increased to 81000/l after 16 months of combined administration of recombinant human granulocyte-colony stimulating factor, recombinant human erythropoietin and cyclosporin A. After 20 months of combined administration, the haematological results were: Hb, 13.1 g/dl; platelets 80000/l: WBC, 9500/l with 40% neutrophils. After recombinant human granulocyte-colony stimulating factor treatment, the myeloid elements of the bone marrow and the number of granulocyte-macrophage colony forming units increased. Bone marrow erythropoiesis and erythroid colonies also increased after recombinant human erythropoietin administration. The clinical course suggested a beneficial effect of haemopoietic growth factors and cyclosporin A in post-hepatitic aplastic anaemia. 相似文献
77.
78.
Autogenous onlay grafting for enhancement of extracortical tissue formation over porous-coated segmental replacement prostheses 总被引:3,自引:0,他引:3
Virolainen P Inoue N Nagao M Ohnishi I Frassica F Chao EY 《The Journal of bone and joint surgery. American volume》1999,81(4):493-499
BACKGROUND: Prosthetic reconstruction with extracortical bone-bridging is an effective method of limb salvage after resection of a malignant or locally invasive benign bone tumor. Use of cancellous bone graft alone is less effective in achieving extracortical bone-bridging. The present study was performed to investigate the effects of a corticocancellous onlay graft on bone and soft-tissue formation over a porous-coated replacement prosthesis in the mid-diaphyseal region of canine femora. METHODS: Bilateral resection of a six-centimeter segment of the femoral diaphysis and reconstruction with a porous-coated segmental prosthesis was performed in six mongrel dogs. In one limb (the experimental side), eight strips of corticocancellous bone were evenly placed around the junctions between the femur and the prosthetic surface. Cancellous bone was placed under and between the strips of cortical bone. No graft was used in the other limb (the control side). The animals were followed for twelve weeks, with sequential assessments of load-bearing and radiographic evaluation. Biomechanical, histological, and microradiographic analyses of the specimens were performed after death. RESULTS: On the control side, load-bearing at four weeks postoperatively was significantly decreased compared with the preoperative value (p<0.05); no difference in these values could be detected on the experimental side. Both the area of the callus and the contact area between the bone and the prosthetic shoulder were greater on the experimental side (p<0.05). The mechanical stiffness and the maximum torque at failure of the extracortical bridging tissue across the junction between the bone and the prosthetic shoulder were eighteen (p<0.007) and five times greater (p<0.05), respectively, on the experimental side. CONCLUSIONS: Extracortical bone-bridging was accomplished with corticocancellous onlay bone-grafting. Without bone-grafting, bone formed only occasionally. Bone-grafting also enhanced the formation of a soft-tissue capsule around the prosthesis. 相似文献
79.
Caspase activation during apoptotic cell death induced by expanded polyglutamine in N2a cells 总被引:12,自引:0,他引:12
Wang GH Mitsui K Kotliarova S Yamashita A Nagao Y Tokuhiro S Iwatsubo T Kanazawa I Nukina N 《Neuroreport》1999,10(12):2435-2438
Huntington disease (HD) is an autosomal dominant neurodegenerative disorder. To investigate the mechanism of neurodegeneration induced by mutant huntingtin, we developed a stable neuro2a cell line expressing truncated N-terminal huntingtin (tNhtt) with EGFP using the ecdysone-inducible system. The formation of aggregates and the cell death induced by expression of tNhtt with expanded polyglutamine was repeat length- and dose-dependent. Caspases were activated, and the death substrates of caspases, lamin B and ICAD (an inhibitor of caspase-activated DNase), were cleaved in this cell death process. The cleavage of lamin B was inhibited by caspase inhibitors. These findings suggest that the cell death induced by tNhtt with expanded polyglutamine is mediated by caspases. 相似文献
80.