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81.
The accumulation of oxygen free radicals is reported to occur in the organs subjected to temporary ischemia followed by reperfusion, resulting in the fatal outcome of the animals. The effects of human SOD, a representative scavenger of oxygen free radicals, on the survival rates were investigated in the rats with temporary splanchnic ischemia. The temporary ischemia was induced by the occlusion of anterior mesenteric and celiac arteries for 30min under anesthesia. Prior and after treatment with 2mg/100g of human SOD, iv or sc, produced significant improvements in survival rates. Human SOD, cloned from human placenta DNA and expressed in microorganisms, has extreme homogeneity. The results suggest the possible introduction of human SOD into clinical field as an effective scavenger of oxygen free radicals.(Ogawa R, Bitoh H, Ohi Y: The effect of human SOD on the survival rate in rats with temporary splanchnic ischemia. J Anesth 2: 41–45, 1988)  相似文献   
82.
Developments in the treatment of childhood cancer have beenevaluated in patients who had been treated in the National Children'sHospital from 1965 to 1987. The total number of patients was867, of which leukemia accounted for 376, malignant lymphoma61, neuroblastoma 174, Wilms' tumor 55, yolk sac tumor 29, rhabdomyosarcoma36 and hepatoblastoma 30. Patients were divided into three timeintervals: the 1960s, 1970s and 1980s. A marked improvementin five-year survival was recognized in Wilms' tumor and yolksac tumor, amounting to 80%, followed by rhabdomyosarcoma, acutelymphoblastic leukemia and malignant lymphoma. There was noimprovement in patients with acute non-lymphoblastic leukemia,neuroblastoma and hepatoblastoma. Prognostic factors for neuroblastomawere further analyzed, and the age of onset and stage of diseasewere found to have remained constant for 23 years. Factors relatingto the improvement of survival were discussed.  相似文献   
83.
Although ileal conduit diversion is widely accepted in the treatment of the patients undergoing radical cystectomy, many patients would prefer other alternatives which allow continence. and urination through the urethra. We describe a new procedure in which a segment of detuburalized right colon is used as a continent reservoir. Eight patients, 7 after radical cystectomy for bladder cancer and one after total exenteration for rectal cancer, have undergone colon bladder replacement. New created bladder had a capacity of 300 to 600 ml. All patients could pass urine through the urethra but one is on self-catheterization. Five of the 8 patients had no residual urine. Three months after operations 4 were totally continent and 3 were satisfactorily dry during daytime but slightly enuretic. Excretory urography showed no abnormalities in their upper urinary tract. Considering the "quality of life' of a patient, this procedure can be an ideal option for selected patients.  相似文献   
84.
This report concerns a case of solitary extramedullary plasmacytoma of the left submandibular lymph node in a 56-year-old man. The tumor showed monoclonal proliferation of abnormal plasma cells which revealed highly positive stainings of both methylgreen pyronin and kappa light chain using the immunoperoxidase technique in the cytoplasms, and further revealed massive'.amyloid'deposits in the stroma, which suggested the possibility of sequential amyloid formation upon the secretion of paraprotein by tumor cells.  相似文献   
85.
The interaction between polymer and solvent in highly concentrated polymer solutions was studied by inverse gas-liquid chromatography as a function of the molecular weight of polymer. The heat interaction parameter was estimated for the systems polystyrene(PS)-benzene, -toluene, -pyridine, -ethylbenzene, and -anisole. It was found that the heat interaction parameter for the concentrated polystyrene systems PS-toluene, PS-pyridine, and PS-benzene exhibits a similar behavior as in the dilute polystyrene solutions determined by calorimetry at 298,15 K. Further, the heat interaction parameter in both the concentrated and dilute polymer solutions is considerably dependent on the molecular weight of polymer.  相似文献   
86.
The body of a Japanese flounder (Paralichthys olivaceus) changes from a symmetrical to an asymmetrical form during metamorphosis. To obtain detailed information on the mechanisms of the migration of the right eye to the left side, soft and hard tissues in the head of larval flounders were examined using transmission electron microscopy (TEM). Retrorbital vesicles (Rvs) are pairs of sac-like structures under the eyes. It has been suggested that the asymmetrical development of Rvs, with the right (blind) one being bigger than the left, is the driving force behind eye migration. The present study revealed that the ultrastructure of the Rv sheath is quite similar to that of a lymphatic capillary. Thus, it is possible that the Rv is a part of the lymph system, and is probably related to the secondary vascular system in teleosts. If we assume that the Rv sheath has a high permeability to liquid, similar to lymphatic capillaries, it is not plausible that the active expansion of the Rv pushes the eyeball. On the other hand, the pseudomesial bar (Pb) is a bone that is unique to flounders and is present only on the right (blind) side. At the beginning of eye migration, an aggregation of fibroblast-like cells is observed in the dermis under the right eye, where the Pb will subsequently be formed. These cells have a well-developed rough endoplasmic reticulum (rER) and mitochondria, and are probably responsible for formation of the thick layers of collagen fibrils around them. Since it is unlikely that the active expansion of the Rv causes eye migration, the role played by the Pb and its rudiment becomes more significant in right eye migration in the Japanese flounder becomes more significant.  相似文献   
87.
The gene Bcl11b, which encodes zinc finger proteins, and its paralog, Bcl11a, are associated with immune-system malignancies. We have generated Bcl11b-deficient mice that show a block at the CD4-CD8- double-negative stage of thymocyte development without any impairment in cells of B- or gammadelta T cell lineages. The Bcl11b-/- thymocytes showed unsuccessful recombination of V(beta) to D(beta) and lacked the pre-T cell receptor (TCR) complex on the cell surface, owing to the absence of Tcrb mRNA expression. In addition, we saw profound apoptosis in the thymus of neonatal Bcl11b-/- mice. These results suggest that Bcl11b is a key regulator of both differentiation and survival during thymocyte development.  相似文献   
88.
The effects of chronic administration of phenytoin, a common anticonvulsive drug, on immune responses were studied in mice. Anti-keyhole limpet haemocyanin (KLH) IgE antibody response after KLH-immunization was enhanced in phenytoin-treated mice. Proliferative responses of spleen cells induced with KLH, concanavalin A (ConA), lipopolysaccharide and anti-CD3 antibody were reduced in phenytoin-treated mice. Accessory function of spleen adherent cells on ConA-induced T cell proliferative response was reduced in phenytoin-treated mice. KLH-induced IL-4 production of spleen cells was enhanced, while IFN-gamma production was reduced in phenytoin-treated mice. In addition, production of IL-1 alpha, but not IL-6 and IL-12 by spleen adherent cells from phenytoin-treated mice was reduced. Natural killer cell activity was reduced in phenytoin-treated mice. These results suggest that phenytoin treatment preferentially induces a Th2 type response. We also observed that plasma ACTH and corticosterone levels were increased in phenytoin-treated mice, and speculated that phenytoin might act directly and indirectly, through HPA axis activation, on the immune system to modulate Th1/Th2 balance.  相似文献   
89.
Adjuvant and antitumor activities of synthetic 6-O-"mycoloyl"-N-acetylmuramyl-L-alanyl-D-isoglutamine were examined. All the synthetic 6-O-corynomycoloyl-, 6-O-mocardomycoloyl-, and 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine were active as adjuvants for cell-mediated immune responses. However, 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine was less active as an adjuvant on circulating antibody formation. It was shown that pyrogenic activity of N-acetylmuramyldipeptide was reduced by 6-O-acylation with mycolic acid, but not with nocardomycolic or corynomycolic acid. Tumor-suppression activity was observed by the synthetic 6-O-mycoloyl-N-acetylmuramyl-L-alanyl-D-isoglutamine by using transplantable tumor in syngenic mice.  相似文献   
90.
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