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81.
82.
Yasuyuki Tezuka Hiroshi Imai Tomoo Shiomi 《Macromolecular chemistry and physics.》1997,198(2):627-641
A series of mono- and bifunctional polystyrenes ( 1 c and 1 ′ c ) having 1-methylpyrrolidinium salt end groups were prepared through sequential derivatization, i.e., tosylation and quaternization reactions, of prepolymers having 3-hydroxypropyl groups ( 1 a and 1 ′ a ) produced by end-capping reactions of the relevant living polymers. The 1-methylpyrrolidinium salt end group was found to undergo a selective ring-opening reaction at 100°C by nucleophilic attack of a benzoate counter anion introduced by ion-exchange reaction. The ion-coupling reaction of 1 c and 1 ′ c with poly(styrene-co-acrylate salt) was found to take place upon coprecipitation of an equimolar mixture into methanol to afford ionically linked pseudo-graft and network products, respectively. The subsequent heat treatment, converting the ionic bond into a covalent one, results in branched and crosslinked polystyrene with predetermined structural parameters. 相似文献
83.
Yoshio Iwakura Katsumi Hayashi Koichi Inagaki 《Macromolecular chemistry and physics.》1967,104(1):56-65
L - and DL-2-Alkyl-2-isocyanatoethyl chloroformates were synthesized by the phosgenation of the corresponding amino alcohols. These optically active or racemic difunctional compounds were submitted to polycondensation-addition with various diamines to form high molecular weight polyurethan-ureas having asymmetric carbon atoms along the main chain. The optically active polyurethan-ureas obtained had slightly higher melting points than the corresponding racemic polymers. 相似文献
84.
Itoh Y Igarashi T Tatsuma N Imai T Yoshida J Tsuchiya M Murakami M Fukunaga Y 《Autoimmunity》2000,32(3):193-197
We have previously reported that approximately 50% of children with chronic nonspecific complaints were positive for antinuclear antibodies (ANA), and that a novel autoantibody to a 62 kD protein (anti-Sa) was found in 40% of these ANA-positive patients. Therefore, we proposed a distinct disease entity termed autoimmune fatigue syndrome (AIFS). We hypothesized that if autoimmune mechanisms did play an important role in the pathogenesis of AIFS, it is possible that it is immunogenetically regulated as observed in other autoimmune disorders. In order to examine the immunogenetic background of AIFS patients, HLA-A, -B, -C, and -DR loci were analyzed serologically in 61 AIFS patients. AIFS was found to be positively associated with the class I antigen HLA-B61 and with the class II antigen HLA-DR9, with odds ratios of 2.77 (p = 0.015, Pcorr = 0.48) and 2.60 (p= 0.012, Pcorr = 0.17), respectively. A negative association was also found between AIFS and HLA-DR2 with odds ratio of 0.25 (p = 0.029, Pcorr = 0.041). When comparing anti-Sa positive AIFS patients with healthy controls, the odds ratios associated with HLA-B61, DR9, and DR2 were 3.42 (p = 0.021, Pcorr = 0.22), 3.96 (p = 0.0011, Pcorr = 0.015), and 0.16 (p = 0.0022, Porr = 0.031), respectively. Thus, the HLA associations observed in this study suggested that immunogenetic background might play a role in AIFS. 相似文献
85.
Because completely opposite results have been reported on the water permeability of the rabbit descending limbs of Henle's loop (DLH), we rigorously examined water permeability of the upper portion of the descending limb of the rabbit long-looped nephron. Even when the double-cannulation method was used in an attempt to reduce the resistance of tubular outflow, the collected fluid-to-perfusate inulin ratio was equal to or very close to the bathing fluid-to-perfusate osmolality ratio, indicating that osmotic equilibration occurred along the tubule by absorption of water. When perfusion rates were controlled by varying the height of the fluid reservoir connected to the perfusion pipette, osmotic (Pf) as well as diffusional (Pdw) water permeability was shown to be correlated with perfusion rate and/or perfusion pressure. Pf and Pdw at zero perfusion rate as determined from the values of the intercept of regression lines were 253 X 10(-3) and 4.54 X 10(-3) cm X s-1, respectively. The maximal values for Pf and Pdw were 737-1,098 X 10(-3) and 18.3 X 10(-3) cm X s-1, respectively. By changing the resistance to perfusion at the tubular outflow, it was shown that changes in Pf paralleled changes in perfusion rate rather than changes in perfusion pressure. Under stop-flow conditions the luminal fluid volume rapidly decreased after the osmolality of the bathing fluid was increased, suggesting that the segment is highly permeable to water even at zero flow rate. Reflection coefficients for urea and NaCl were 1.01 and 0.82, respectively. These data support the view that this segment is highly permeable to water and that increases in osmolality along the DLH in vivo may be accounted for mainly by abstraction of water rather than addition of solutes. 相似文献
86.
Yutaka Imai Takashi Sato Mitsunori Yamakawa Takeshi Kasajima Akio Suda Yoshihiro Watanabe 《Pathology international》1989,39(2):127-134
Rheumatoid arthritis (RA) is one of the immune complex (IC) diseases in which lymphoid germinal centers (GCs) are found in the synovial tissue. Simultaneously, patients with RA often show swelling of lymph nodes. The morphology and function of the lymph node GCs in patients with RA is not clear. The aim of this study was to evaluate the differences in morphology and immunoreactions to complement (C) components, their receptors, and lgM-rheumatoid factor (RF) between synovial GCs and lymph-node GCs in RA. Furthermore, the relationship between these immuno-reactive substances and follicular dendritic cells (FDCs) in GCs was investigated. The tissues examined were 41 RA synovial specimens, seven RA lymph nodes with massive lymphadenopathy, and 10 non-RA lymph nodes. The number of synovial GCs was relatively decreased in comparison with lymph-node GCs in RA, and the diameter of each synovial GC was smaller than that of each lymph-node GC. The synovial GCs were edematous and less cellular, and moreover, those from RF-seronegative cases were smaller than those from RF seropositive cases. On the other hand, the lymph-node GCs in RA were larger, more cellular and hyperplastic, but contained more tingible-body macro-phages (TBMs) and neutrophils. In the GCs of both synovial tissues and lymph nodes in RA, early C components (C1q, C4, C3c, C3d), IgM RF, and C3b receptor (C3bR) and C3d receptor (C3dR) were expressed as a lacy network by light microscopy, and were demonstrated on the surfaces of FDCs and lymphocytes, and in the intercellular spaces by electron microscopy. Furthermore, immuno-staining for dendritic reticulum cells (DRC, DAKO DRC1) was observed in a lacy pattern by light microscopy and on the cell surface of FDCs by electron microscopy. In the GCs of non-RA lymph nodes, early C components, C3bR, C3dR, and DRC showed a similar reaction pattern, but IgMRF did not. Consequently, no marked difference in immunoreactions in the GCs, except for the immunoreactions of late C components, was found between synovial tissues and lymph nodes in RA. On the basis of these findings, we discuss the possibility of the presence of a RF-IC. 相似文献
87.
Eosinophil response in mast cell-deficient W/WV mice 总被引:1,自引:0,他引:1
Y Nawa M Owhashi J Imai T Abe 《International archives of allergy and applied immunology》1987,83(1):6-11
The combination of cyclophosphamide treatment and Toxocara canis infection is known as an effective way of causing a high level of eosinophilia in mice. When this treatment was applied to congenitally anemic, mast cell-deficient W/WV mice, eosinophil response was far less than that of their normal littermate +/+ mice. The degree of the defective eosinophil response in the peripheral blood of W/WV mice was severer than that in the bone marrow. The defective eosinophil response of W/WV mice was completely restored by bone marrow grafting 8 weeks prior to cyclophosphamide treatment and T. canis infection. The kinetics of the recovery of eosinophil response in the bone marrow of W/WV mice after bone marrow grafting was faster than that in the peripheral blood. Chemotactic reactivity of eosinophils obtained from bone marrow or peritoneal cavity of W/WV mice was essentially comparable to that of +/+ mice. These results suggest that, in addition to the production of eosinophils in the bone marrow, mast cell-derived factors play an important role in the mediation of peripheral blood eosinophilia. 相似文献
88.
Sakaguchi M Toda M Ebihara T Irie S Hori H Imai A Yanagida M Miyazawa H Ohsuna H Ikezawa Z Inouye S 《The Journal of allergy and clinical immunology》2000,106(3):579-584
BACKGROUND: Most children with anaphylaxis to measles, mumps, and rubella vaccines had shown sensitivity to bovine gelatin that was included in the vaccines. Recently, it was found that bovine type I collagen, which is the main content in the gelatin, is a major allergen in bovine gelatin allergy. Fish meat and skin also contain type I collagen. OBJECTIVE: The present study was designed to investigate IgE antibody to fish gelatin in children with fish allergy. METHODS: Serum samples were taken from patients in 3 groups: (1) 10 patients with fish allergy and specific IgE to fish meat; (2) two patients with allergies to both fish meat and bovine gelatin and specific IgE to fish meat and bovine gelatin; and (3) 15 patients with atopic dermatitis and specific IgE to fish meat. Various fish gelatins (type I collagen) were prepared from fish skin. IgE antibody to fish gelatin was analyzed by using ELISA and immunoblotting. RESULTS: Of 10 patients with fish allergy, 3 had specific IgE to fish gelatin. Of two patients with fish allergy and bovine gelatin allergy, all had specific IgE to fish gelatin. Of 15 patients with atopic dermatitis and specific IgE to fish meat, 5 had specific IgE to fish gelatin. Furthermore, IgE from pooled serum of the patients reacted with both the alpha1 and alpha2 chains of fish type I collagen in immunoblots. There is cross-reactivity among gelatins from various fishes, but there is little cross-reactivity between fish and bovine gelatins. CONCLUSION: Some fish-sensitive patients possessed IgE antibody to fish gelatin. Fish gelatin (type I collagen) might be an allergen in subjects with fish allergy. 相似文献
89.
In an attempt to clarify the cytological characteristics of the RES cells in the lymph nodes and their embryological correlations, lymph nodes and lymph node anlages of germ-free rats, nude mice, and human fetuses were light and electron microscopically examined. On the basis of differences of intracellular organelles, their behaviors for reticulum fibers and of endogenous peroxidatic activity, histiocytes should be reasonably distinguished from the cells conventionally called reticulum cells. Reticulum cells and histiocytes respectively are destined to differentiate in different directions from the early stage of development of the lymph node anlage. Sinus endothelial cells are ontogenetically originated and differentiated from the endothelial lining cells of lymphatic vessels. Primitive reticular cells are differentiated into mature reticulum cells in the lymph nodes, they transform into the lympho-reticular cells, further into lymphoblasts, and finally develop into medium-sized lymphocytes. 相似文献
90.
Orita S Hirose M Takahashi S Imaida K Ito N Shudo K Ohigashi H Murakami A Shirai T 《Toxicologic pathology》2004,32(2):250-257
Effects of dietary administration of 1'-acetoxychavicol acetate (ACA) and the novel synthetic retinoids 4-[1-hydroxy-3-oxo-3-(5,6,7,8-tetrahydro-3-hydroxy-5,5,8,8-tetramethyl-2-naphthalenyl)-1-propenyl]benzoic acid (Re-80); 4-[(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)carboxamido]benzoic acid (Am-580); and 6-[(3,5-di-tert-butylphenyl) carbamoyl]nicotinic acid (Am-55P) were examined using a two-stage rat carcinogenesis model. A total of 190 female SD rats was treated sequentially with 1,2-dimethylhydrazine (DMH, s.c.); 7,12-dimethylbenz(a)anthracene (DMBA, i.g.); and 2,2'-dihydroxy-di-n-propylnitrosamine (DHPN, in the drinking water) during the first three weeks (DDD-initiation), and an additional 60 rats received the vehicle alone (non-initiation). One week after the completion of the initiation period, they were divided into nine groups and administrated Re-80 (at dose levels of 1.0 or 0.4 ppm), Am-580 (20 or 4 ppm), Am-55P (20 ppm), ACA (100 ppm), all-trans-retinoic acid (10 or 2 ppm) or no supplement in the diet for 33 weeks, until survivors were euthanatized at week 37 weeks. After DDD-initiation, all-trans-retinoic acid at the high dose delayed the development of mammary tumors. The multiplicity of colon tumors in the group fed Am-55P and the incidences of nephroblastomas with ACA or Am-580 were decreased as compared with the control values, but the other chemicals had no modifying effects on tumor development in any organs. Thus, among ACA and the novel synthetic retinoids tested, only Am-55P showed a weak inhibitory effect on a neoplasm of general interest under the present experimental conditions. 相似文献