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51.
Masayuki Yokoyama Hayato Anazawa Akeo Takahashi Shohei Inoue Kazunori Kataoka Nobuhiko Yui Yasuhisa Sakurai 《Macromolecular chemistry and physics.》1990,191(2):301-311
Novel segmented multiblock copolymers ( 7 ) were synthesized by linking poly(ethylene oxide) (PEO) blocks with poly(β-benzyl L -aspartate)(PBLA) blocks via urethane and urea bonds, which were formed by the reaction of 4,4′-methylenediphenyl isocyanate ( 5 ) with the terminal hydroxyl groups of α-hydro-ω-hydroxypoly(oxyethylene) ( 4 ) and the terminal amino groups of poly(β-benzyl L -aspartate)-block-iminohexamethyleneimino-block-poly(β-benzyl L -aspartate) ( 3 ) [prepared from 1,6-hexanediamine ( 1 ) and β-benzyl L -aspartate N-carboxy anhydride ( 2 )], respectively. Membranes with various water contents were obtained from these copolymers by changing the lengths of the PEO and PBLA segments. The study of the permeation of 1-phenyl-1,2-ethanediol, vitamin B12 and myoglobin through the membranes showed a high dependency of the permeability on the molecular weight of the solutes. 相似文献
52.
Kikuchi T Ichimiya S Kojima T Crisa L Koshiba S Tonooka A Kondo N Van Der Saag PT Yokoyama S Sato N 《International immunology》2004,16(6):831-841
In this study, we investigated the localization and functional significance of p53 tumor suppressor-like molecules, p63 and p73, in human thymic epithelial cells (TECs). Immunohistochemical studies showed particular distribution profiles of p63 and p73 in thymic epithelium, in which cortical TECs preferentially expressed p63 in their nuclei whereas subcapsular and medullary TECs expressed both p63 and p73 in their nuclei. The wide distribution of p63 in TECs was further suggested by studies using TECs of primary culture. In vitro studies using two human TEC lines demonstrated that p63 was capable of up-regulating intercellular adhesion molecule-1 (ICAM-1) and enhancing the production of IL-6 and IL-8. Moreover, in vitro studies also indicated that p73, but not p63, had the capacity to induce granulocyte macrophage colony stimulating factor (GM-CSF) and granulocyte colony stimulating factor (G-CSF) in the TEC lines. These findings suggest that p63 would regulate the cell adhesive property through ICAM-1/LFA-1 interaction and the production of IL-6 and IL-8, probably in all TEC subtypes. p73 in subcapslar and medullary TECs was suggested to play a role in the regulation of the production of GM-CSF and G-CSF, which might stimulate other stromal cells such as dendritic cells, macrophages and endothelial cells around these regions. 相似文献
53.
54.
Kazuma Ohyashiki Mitsuo Oshimura Takayo Toyoda Nobuhiko Sakai Hisao Ito Kohtaro Yamamoto Akira Tonomura 《Cancer Genetics and Cytogenetics》1984,11(2):215-219
We encountered a 38-year-old Japanese male patient with chronic myelogenous leukemia (CML), whose bone marrow and peripheral blood cells during the chronic and blastic phases contained a complex Ph1 translocation and an extra Y chromosome [i.e., 47,XYY,t(9;22;13)(q34;q11;q14)]. A karyotypic analysis of PHA-stimulated lymphocytes showed the constitutional karyotype to be 47,XYY. Thus, it was considered that CML with a complex Ph1 translocation developed in an XYY male; such a case has not been reported, so far. A B-lymphocyte cell line with the complex Ph1 translocation was established by the procedure of Epstein-Barr virus transformation. The presence of the complex Ph1 translocation in the B-lymphocyte cell line suggests that some of the B lymphocytes in this patient originated from the CML clone. 相似文献
55.
Sekigawa I Matsushita M Lee S Maeda N Ogasawara H Kaneko H Iida N Hashimoto H 《Autoimmunity》2000,33(1):37-44
Current investigations into the role of CD8+ T cells and their derived cytokine, interleukin (IL)-16, in the induction of CD4+ T cell abnormalities in systemic lupus erythematosus (SLE) were reviewed and discussed on the basis of results mainly obtained in our laboratory. 相似文献
56.
Shuji Matsuzawa Kazuo Yamaura Ryuzo Maeda Kenji Ogasawara 《Macromolecular chemistry and physics.》1979,180(1):229-239
The melting temperatures of a syndiotacticity-rich poly(vinyl alcohol)-water gel were measured for concentrations below 70g.dm-3. In the gel chilled at a temperature below about 15°C the melting point first decreased monotonously then sharply in a jump and again monotonously with decreasing concentration, whereas in the gel chilled above 20°C the melting point decreased monotonously through-out. The change of the shear modulus of a gel chilled at 0°C with the rise of temperature from 0°C to the melting point was also measured. Initially the shear modulus decreased, then increased to a maximum value, and at last decreased towards the melting temperature, whereas a gel chilled at 40°C kept an almost constant value during heating from 40°C up to a high temperature and then decreased with further rise of temperature. The turbidity of dilute solutions chilled at 0°C passed a minimum and maximum with the rise of temperature in accord with the minimum and maximum of the shear modulus. It is thus concluded that in the gel chilled at temperatures below 15°C the junctions grow to some extent with the rise of temperature. 相似文献
57.
F Nakanishi M Sugiishi T Ogasawara I Sugiura T Kinoshita Y Ito A Hoshino 《Gan to kagaku ryoho. Cancer & chemotherapy》1985,12(6):1339-1344
Twenty-two patients with advanced adenocarcinoma of the lung were treated with the combination chemotherapy "EACAM" consisting of cyclophosphamide (333mg/m2 X 1), adriamycin (27mg/m2 X 1), cisplatin (25mg X 5), nimustine (33mg/m2 X 1), and methotrexate (27mg/m2 X 3). This regimen was repeated once every 4 or 5 weeks. One complete response (CR) and 8 partial responses (PR) were obtained in 21 evaluable patients and the response rate was 42.9%. It has not been possible to calculate the median survival time for all of the evaluable cases, since 13 of them are still alive up to the present time. The side effects observes were as follows: nausea and vomiting (81.8%), alopecia (81.8%), stomatitis (22.7%), leukocytopenia less than 2,000/mm3 (45.5%), and thrombocytopenia less than 5 X 10(4)/mm3 (18.2%). Apart from strong myelosuppression, no severe infection or bleeding tendency was noticed. A mild elevation of serum createnine was observed in one patient, and no patients developed renal insufficiency. The combination chemotherapy "EACAM" is therefore considered to be a very effective and tolerable treatment for adenocarcinoma of the lung. 相似文献
58.
Yoshiyuki Suehara Shinji Kohsaka Takuo Hayashi Keisuke Akaike Aiko Kurisaki-Arakawa Shingo Sato Eisuke Kobayashi Sho Mizuno Toshihide Ueno Takeshi Morii Tomotake Okuma Taisei Kurihara Nobuhiko Hasegawa Kei Sano Keita Sasa Taketo Okubo Youngji Kim Hiroyuki Mano Tsuyoshi Saito 《Clinical orthopaedics and related research》2021,479(4):838
59.
Hypoxia-ischemic insult in neonatal rats induced slowly progressive brain damage related to memory impairment 总被引:4,自引:0,他引:4
Mishima K Ikeda T Aoo N Takai N Takahashi S Egashira N Ikenoue T Iwasaki K Fujiwara M 《Neuroscience letters》2005,376(3):194-199
The present study was designed to determine potential associations between the brain damage induced by hypoxic-ischemic (HI) insult and spatial learning impairment in an eight-arm radial maze task. We first determined the pathological outcomes after 2, 5, 9, and 17 weeks of recovery following the HI insult. The results show that the brain damage progressed from 2 up to 17 weeks of recovery. To clarify the time course of the brain damage changes, we investigated the histological changes of the same individual with magnetic resonance imaging (MRI) after 5, 9, and 57 weeks of recovery following the HI insult. The MRI changes were similar to the histological changes, and the brain damages were exacerbated in the contralateral hemisphere after 57 weeks of recovery following the HI insult. To investigate whether alteration in brain function was correlated with MRI and histological changes, the rats were made to find their way through an eight-arm radial maze was performed at either 7th or 16th weeks of recovery. According to the results, the spatial learning impairments of rats in the maze starting at 16 weeks of recovery were more severe than those at 7 weeks of recovery, indicating that the impairments were progressive and depended on the degree of brain damage. The results of the present study are the first demonstration that the evolutional and specific brain damage following the HI insult is slowly and progressively exacerbated to the contralateral hemisphere and rats who experience the HI are at risk for showing a late impairment of brain function. 相似文献
60.
Mutagenicity of the bile of dogs with an experimental model of an anomalous arrangement of the pancreaticobiliary duct 总被引:8,自引:0,他引:8
Qian Dong; Kinouchi Takemi; Kunitomo Kazufumi; Kataoka Keiko; Matin Muhammed Abdul; Akimoto Shigeru; Komi Nobuhiko; Ohnishi Yoshinari 《Carcinogenesis》1993,14(4):743-747
To learn the reasons for the high incidence of biliary carcinomain patients with anomalous arrangement of the pancreaticobiliaryduct (APBD) mutagenicity of the bile of APBD-modeled dogs thathad received a dorsal pancreatico-cholecystostomy was assayedby the Ames Salmonella mutation test. The bile from two outof 18 APBD dogs was mutagenic for Salmonella typhimurium strainTA98 under the condition of metabolic activation by rat liverS9 fraction, while the bile from 17 normal dogs was not mutagenic.Furthermore, the bile from five APBD dogs i.p. administered1-nitropyrene (1-NP), which is a typical environmental mutagen,was more mutagenic for strain TA98 than that from 1-NP-treatednormal dogs. The bile from the APBD dogs had very high amylaseactivity, indicating that the bile contained pancreatic juiceas a result of the pancreatico-cholecystostomy. When pancreaticjuice from a normal dog was added to the bile from 1-NP-treatednormal dogs, mutagenicity of the bile increased 1.6- to 2.0-fold.Furthermore, sulfatase increased the mutagenic activity of thebile in the presence of the pancreatic juice. HPLC revealedthat the bile from a 1-NP-treated APBD dog contained mutagenic1-nitro-6/8-hydroxypyrene and 1-nitro-3-hydroxypyrene, whilebile from a 1-NP-treated normal dog did not contain these deconjugatedproducts. The pancreatic juice from a normal dog had very high-glutamyltransferase (GGT) and aminopeptidase activities andlow sulfatase activity, but it had no ß-glucuronidaseactivity. In addition, the bacteria that easily infect the biliaryduct of APBD dogs, Escherichia coli, Klebsiella, Enterobacterand Proteus, had high ß-glucuronidase activity. Inparticular, Klebsiella showed a very high sulfatase activity.These results suggest that pancreatic juice enzymes and bacteriainfecting the biliary duct deconjugate the detoxified mutagensin the bile and induce mutagenicity of the bile from APBD dogsor APBD patients. 相似文献