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81.
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Forehead recontouring in endoscopic surgery is presented. Eleven cases of protruded forehead deformity caused by benign tumor and one case of concave deformity caused by depressed frontal bone fracture were treated. All lesions were approached through incisions made in the hair-bearing area and operated on endoscopically. This method left no scars on the forehead, and the results were satisfactory. It is considered to be an excellent procedure with regard to cosmetic results.  相似文献   
83.
In Parkinson's disease the cell death of dopamine neurons has been proposed to be mediated by an apoptotic death process, in which nitric oxide may be involved. This article reports the induction of apoptosis by nitric oxide and peroxynitrite in human dopaminergic neuroblastoma SH-SY5Y cells and the antiapoptotic activity of (-)-deprenyl. After the cells were treated with a nitric oxide donor, NOR-4, or a peroxynitrite donor, SIN-1, DNA damage was quantitatively studied using a single-cell gel electrophoresis (comet) assay. NOR-4 and SIN-1 induced DNA damage dose-dependently. Cycloheximide and alkaline treatment of the cells prevented the DNA damage, indicating that the damage is apoptotic and that it depends on the intracellular signal transduction. Superoxide dismutase and the antioxidants reduced glutathione and alpha-tocopherol protected the cells from the DNA damage. (-)-Deprenyl protected the cells from the DNA damage induced by nitric oxide or peroxynitrite almost completely. The protection by (-)-deprenyl was significant even after it was washed from the cells, indicating that (-)-deprenyl may activate the intracellular system against apoptosis. These results suggest that (-)-deprenyl or related compounds may be neuroprotective to dopamine neurons through its antiapoptotic activity.  相似文献   
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Maruyama  F. 《Computer》1985,18(2):22-32
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86.
BACKGROUND AND PURPOSE: To detect areas of cerebral perfusion from bypass arteries after vascular reconstruction, we administered selective intraarterial microsphere tracer into the external carotid arteries and determined (via single-photon emission computed tomography [IA-SPECT]) whether the distribution of radiotracer matched the arteriographic distribution of contrast material as shown on external carotid angiograms. METHODS: We compared the extent of regional distribution of tracer after external carotid artery injection of 20 to 40 MBq of 99mTc-HMPAO or 99mTc-ECD with that of contrast medium on the external carotid angiograms in 582 cortical regions in 12 patients with atherosclerotic occlusive disease and in 18 patients with moyamoya disease. RESULTS: Marked accumulation of tracer was found only in the expected, specific, newly developed areas of cerebral perfusion from bypass arteries. The regional distribution of tracer corresponded to that of contrast medium in 523 regions (90%) and did not correspond in 59 regions (10%). Significant overestimation of the distribution of contrast material relative to that of tracer was observed in the patients with moyamoya disease. CONCLUSION: SPECT showed slightly different distribution of tracer from that predicted by conventional angiography. IA-SPECT should enhance the analysis of newly developed areas of cerebral perfusion from the bypass arteries.  相似文献   
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Regional chemotherapy was given 16 unresectable gastric cancer patients. Two types of the chemotherapy, intraperitoneal (IP) and intraaortic (IA) administration, were carried out. The control group was comprised of 17 patients. The response of the chemotherapy for primary tumor was 36.4% in the IP group and 20% in the IA one. Among these patients, 2 of 11 in IP and 1 of 5 in IA were able to resect the primary tumor. The 50% survival time of IP, IA and control was 347, 227 and 78 days, respectively. One-year survival rates of IP, IA and control were 68%, 29% and 0%, respectively. IP showed a significantly longer survival rate than controls (p < 0.001). All but one patient was able to stay at home. Intraperitoneal chemotherapy showed both local and systemic effects in unresectable gastric cancer.  相似文献   
90.
Emulsion polymerization of styrene (St) and vinyl acetate (VAc) in the presence of conventional polyvinyl alcohol (PVA), PVA modified with a terminal alkyl group or PVA modified with a terminal thiol group (HS-PVA) was compared. Whereas stable PVAc latexes were obtained, a stable PSt latex was obtained only in the case of HS-PVA. From the adsorption isotherms of these PVAs on the surface of PVAc and PSt latex particles, as well as the grafting efficiencies of VAc and St onto HS-PVA in relation to the stability of the polymerization process, the role of PVA in the emulsion polymerization was discussed.  相似文献   
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