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951.
To assess the efficacy of cancer chemotherapy, an important index is apoptosis of the target cells, which can usually be confirmed by electron microscopy (EM). We established a new experimental technique, whereby cancer cells (MKN45) were distributed in thin collagen gel as one or two cell layers, and cultured with anti-cancer drugs (5-FU and CDDP). The cells were stained with fluorescent Hoechst 33258 (Ho) and photographed, then with hematoxylin and eosin (H&E) and again photographed, and processed for EM. This approach allowed us to characterize the patterns of death of single cells in detail. There were six patterns of cell damage: two patterns of apoptosis, early peripheral condensation of chromatin and late apoptotic bodies, two patterns of necrosis, cytoplasmic swelling and washed-out images, and two further patterns, with morphological features of both apoptosis and necrosis, neither classified into necrosis nor apoptosis. The results show that cell death patterns can be mostly determined by combining observations of Ho and H&E-stained cells without the necessity for EM observation.  相似文献   
952.
BACKGROUND AND OBJECTIVE: To describe the biodistribution of a hydrophilic sensitizer, mono-L-aspartyl chlorin e6 (NPe6), in a primate model of choroidal neovascularization (CNV). MATERIALS AND METHODS: NPe6 (25 mg/kg) and indocyanine green (ICG, 15 mg/kg) were intravenously administered simultaneously in monkeys with laser-induced CNVs. Eyes were enucleated and examined by fluorescence microscopy immediately, 20 minutes, and 1, 4, and 24 hours after dye injection. RESULTS: Fluorescence peaked in retinal vessels immediately after dye administration; rapid washout began 1 hour postinjection. In contrast, experimental CNV demonstrated little fluorescence immediately after injection, with increased intensity at later time points. Peak dye fluorescence in CNV occurred 1 hour following dye injection. NPe6 fluorescence diminished rapidly and washed out completely by 24 hours. The dye accumulation and retention pattern of ICG dye resembled that of NPe6. CONCLUSIONS: This study demonstrated the selective accumulation of NPe6 photosensitizer and ICG dye within experimental CNV and rapid clearance from the circulation and retinochoroidal tissue.  相似文献   
953.
954.
目的 研究帕金森病痴呆(PDD)及路易体痴呆(DLB)的临床特征和病理学基础。方法 对9例有痴呆伴有帕金森病症状患者的临床特征和病理学进行分析。结果 9例中5例临床诊断为PDD,2例为帕金森病(PD),1例为进行性核上性麻痹(PSP)和1例阿尔茨海默病(AD)。5例PDD的病理亚型是新皮质型3例,边缘型2例。结论 本研究显示PDD与DLB有相似的病理学基础。  相似文献   
955.
956.
The significance of l ‐type amino acid transporter (LAT) 1 expression remains unclear in the metastatic process of human neoplasms, whereas experimental studies have demonstrated that LAT1 is associated with the metastatic process of cancer cells. We compared the immunohistochemical expression of LAT1 and CD98 between the primary site and a concordant pulmonary metastatic site in 93 cancer patients, all of whom had undergone thoracotomy. LAT1, CD98, Ki‐67 labeling index, vascular endothelial growth factor (VEGF), CD31, and CD34 were analyzed by immunohistochemical staining in the resected tumors of 93 cancer patients: 45 colon cancers; nine breast cancers; eight head and neck cancers; 11 genital cancers; 14 soft‐tissue sarcomas; and six other cancers. The expression of these markers was significantly higher in the metastatic sites than in the primary sites. In total, the positive rates of LAT1, CD98, Ki‐67, VEGF, CD31, and CD34 were 40, 24, 56, 41, 45, and 39%, respectively, in the primary sites and 65, 45, 84, 67, 73, and 61%, respectively, in the metastatic sites. LAT1 expression was closely correlated with CD98 expression, angiogenesis, and cell proliferation. The association between LAT1 and CD98 expression was strongest in the primary and metastatic sites. The present study suggests that overexpression of LAT1 and CD98 has an important role to play in the metastatic process of variable human neoplasms. Moreover, LAT1 expression was significantly correlated with cell proliferation and angiogenesis. (Cancer Sci 2008; 99: 2380–2386)  相似文献   
957.
958.
Summary In an 18-year-old male with Eisenmenger syndrome cyanosis and erythrocytosis were increasing. The erythrocytosis diminished following oral bunazosin and phlebotomy was not needed during the treatment. When bunazosin was stopped, the erythrocytosis increased, but when it was resumed, the erythrocytosis and general fatigue diminished.  相似文献   
959.
Summary Two cases with prolapse of all four cardiac valves are described and compared with two similar ones previously reported. The severity and progression of regurgitation of each of the valves differed by case, despite having similar echocardiographic findings consistent with the diagnosis of multiple floppy valves. Two of the four patients had their aortic valve replaced because of severe regurgitation: the excised valves revealed myxomatous degeneration. None of the patients had any stigmata of Marfan or Ehlers-Danlos syndrome, except for the presence of hyperextensive joints. There may be an unknown collagen disorder that caused floppiness in all the valves.  相似文献   
960.
The effect of arginine-vasopressin (AVP) and its analogues upon the endocochlear potential (EP) was examined in the guinea pig. AVP decreased the EP reversibly and dose-dependently like lysin-vasopressin (LVP). V1 antagonist failed to block the effect of AVP upon the EP. V2 agonist reversibly decreased the EP like AVP. The results suggest that V2 receptors mediate the action of vasopressin on the EP.  相似文献   
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