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41.
Mianserin (5-20 mg/kg), like chlordiazepoxide (2.5-10 mg/kg), inhibits the shock-induced suppression of drinking (SSD) in rats. However, in contrast to chlordiazepoxide, the effect of mianserin is not blocked by the benzodiazepine antagonist, Ro 15-1788 (10 mg/kg). Although mianserin does not inhibit [3H]diazepam binding in vitro it has now been found to enhance [3H]flunitrazepam binding to mouse whole brain in vivo at 10-100 mg/kg p.o. These results suggest that mianserin does influence central benzodiazepine receptors, but the mechanism by which it does so differs from that of chlordiazepoxide.  相似文献   
42.
Topographical projections from the thalamus to the putamen in the cat   总被引:1,自引:0,他引:1  
Thalamic projections to the putamen (Put) in the cat were studied by the retrograde horseradish peroxidase method. Major thalamic projections to the Put originate from the midline and intralaminar nuclear regions including the centre médian-parafascicular complex (CM-Pf). The other thalamic projections to the Put arise mainly from the suprageniculate nucleus (Sg), magnocellular division of the medial geniculate nucleus (MGm), caudomedial part of the lateroposterior nucleus (LP) and ventrolateral part of the ventromedial nucleus (VM). The VM projects to the rostral Put, while the posterior thalamic regions (Sg, MGm, LP) project to the caudal Put.  相似文献   
43.
An autopsy case of systemic histiocytosis with excessive deposition of kappa-type light chain crystals was reported in a 58 year-old man who had consistently showed kappa-type light chain paraproteinemia, Bence Jones proteinuria and hypogammaglobulinemia for about 10 years until his death. However, no bony destruction was found by repeated X-ray examinations. At autopsy, extensive hyperplasia of crystal-storing histiocytes was observed in the bone marrow, spleen, liver, lymph nodes, interstitial tissues of visceral organs and loose connective tissues. In the bone marrow and some other tissues, mild proliferation of plasmocytoid cells containing small crystals were found. Histochemically the crystals positively stained with various methods for amino acids and proteins, especially with Weigerts' method for fibrin. Ultrastructurally intralysosomal crystal deposition was confirmed in the storage histiocytes and derivation of the crystals from Golgi's sacculi in the plasmocytoid cells was suggested. Biochemically the crystals were regarded as mainly consisting of dimers of a variable half of light chain immunoglobulin and immunochemically and immunohistochemically reacted to anti-kappa type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells.  相似文献   
44.
To clarify the role of IP-10 in autoimmune liver diseases, we studied the serum levels of IP-10 in 14 patients with autoimmune hepatitis (AIH), 23 patients with primary biliary cirrhosis (PBC), and 65 patients with chronic viral hepatitis (20 type B and 45 type C). The hepatic expression of IP-10 mRNA and the correlation between the serum levels of IP-10 and clinical parameters were also evaluated. In addition to 20 healthy controls, 16 rheumatoid arthritis (RA) patients were included as an extrahepatic inflammatory disease. The serum level of IP-10 was significantly (P < 0.02) higher in patients with AIH, PBC, and chronic hepatitis B and C than in healthy controls, and it was significantly correlated (P < 0.05) with the serum levels of aspartate aminotransferase and alanine aminotransferase in patients with AIH, PBC, and chronic hepatitis B and C. The serum level of IP-10 was not elevated in RA patients. After successful treatment of AIH and chronic hepatitis C, the serum level of IP-10 decreased to the same level as in healthy volunteers. As we previously showed in cases with chronic hepatitis B or C, in situ hybridization in both AIH and PBC cases demonstrated the expression of IP-10 mRNA in hepatocytes around focal or lobular necrosis surrounded by infiltrating mononuclear cells, whereas IP-10 mRNA was not expressed in areas around the damaged bile ducts in PBC cases. The present results suggest that IP-10 is specifically produced by hepatocytes in inflammatory areas irrespective of the aetiology of hepatitis, and that IP-10 may help to recruit T cells to the hepatic lesions in autoimmune liver diseases as well as in chronic viral hepatitis.  相似文献   
45.
Hepatitis B surface antigen possesses the group-specific determinant called a and one or another member from each of two pairs of allelic determinants, d and y as well as w and r, thereby creating the four major subtypes, adw, adr, ayw and ayr. In the sequence of major surface antigen polypeptides made of 226 amino acid residues, lysine or arginine at amino acid position 122 specifies d or y determinant, and lysine or arginine at position 160 specifies w or r determinant, respectively. By means of site-directed mutagenesis and expression of mutant genes in cultured cells, the mechanism for the loss of subtypic determinants on surface antigens was investigated at the molecular level. A rare sample of surface antigen of subtype ad, devoid of w or r determinant, had asparagine at position 160. When it was converted to lysine, the surface antigen of subtype adw was obtained. Two samples of surface antigen were subtyped as ar. They lacked d determinant, despite having lysine at position 122 which usually specified it. They differed from all reported sequences of surface antigen in amino acid 144 or 145. They displayed d determinant when amino acid 144 was converted from glutamic acid to aspartic acid, or when amino acid 145 was changed from alanine to glycine. These results indicate that the key amino acid residue at position 122 or 160 is indispensable for the expression of subtypic determinants and that some distant residues are also crucially involved in conforming them.  相似文献   
46.
Yamaguchi I  Itoh S  Suzuki M  Sakane M  Osaka A  Tanaka J 《Biomaterials》2003,24(12):2031-2036
Crystalline chitosan was prepared from crab tendon consisting mainly of chitin, including various proteins and calcium phosphates. The crab tendon has high mechanical properties due to its aligned molecular structure. Crab tendon components, i.e. proteins and calcium phosphates, were removed by deacetyl treatment using 50wt% NaOH aqueous solution at 100 degrees C, and a subsequent ethanol treatment. As judged from microscopic observations using an optical polarizer, the treated chitosan remained intact regarding its aligned molecular structure, and had a high tensile strength of 67.9+/-11.4MPa. The tensile strength was further enhanced to 235+/-30MPa by a thermal treatment at 120 degrees C, corresponding to the formation of the intermolecular hydrogen bonds.  相似文献   
47.
We report a malformed female infant withde novo interstitial deletion of 4q[46,XX,del(4)(q27q28.2)]. The MN blood type analysis of the family members showed that the patient had an intact blood group-MN locus. The locus of the gene responsible for the MN antigen activity is confined to a 4q28.2–4q31.1 segment on the basis of the result of this patient and the previous mapping data.  相似文献   
48.
Twelve strains of adenovirus serotype 19, isolated from cases of epidemic keratoconjunctivitis in Japan in 1992, 1993, 1997, and 1998, were analyzed by DNA restriction analysis, using restriction endonucleases BamHI, BglI, BglII, EcoRI, HindIII, KpnI, PstI, SacI, SalI, SmaI, and XhoI. Among these 11 restriction endonucleases, EcoRI, PstI, SacI, and SmaI were discriminative enzymes, showing restriction patterns different from those reported previously for the prototype and the variant 19a. This new genome type was isolated in 1997 and 1998, when an increase of epidemic keratoconjunctivitis cases caused by adenovirus serotype 19 was observed for both sporadic and nosocomial infections. Strains from 1992 and 1993 showed restriction patterns similar to those of the worldwide reported variant 19a for all enzymes used. The changes detected in strains from 1997 and 1998 could be the reason for the recent epidemic.  相似文献   
49.
The purpose of this study was to examine, by positron emission tomography (PET), the distribution of [18F]fluoro-deoxy-glucose ([18F]FDG) uptake by human muscles during 35?min of running. Thirteen healthy male subjects were studied, seven of whom participated in the exercise study. Running intensity was kept constant such that the subjects' heart rates were maintained at between 140 and 150?beats per minute. [18F]FDG [62.9 (14.8)?MBq, mean (SD)] was injected after 15?min of running. PET imaging was started immediately after the running ended. The ratio of [18F]FDG uptake by muscles in runners to that in control subjects (r-c ratio) varied from three to six for the muscles of the foot and leg below the knee joint. The r-c ratio of the medial head of the gastrocnemius (MG) was higher than that of its lateral head (LG). The r-c ratio of the rectus femoris (RF) was lower than that of the other three muscles of the quadriceps femoris (QF). The r-c ratio of inactive muscles located above the waist was approximately 0.7. These results suggest that, during the moderate running of this study: (1) glucose uptake by muscles of the foot and leg below the knee joint clearly increases, (2) the r-c ratio differs significantly among the skeletal muscles, which act synergistically, and (3) glucose uptake by inactive skeletal muscles decreases.  相似文献   
50.
For reconstruction and regeneration of hard tissues, scaffold biomaterials with large size pores and high porosity are important, in addition to their roles as supporting frames. To develop a new biodegradable scaffold biomaterial, CO3Ap, which has crystallinity and a chemical composition similar to bone, was synthesized at pH 7.4 and 60 degrees C. Then, the CO3Ap was mixed with a neutralized collagen gel and the CO3Ap-collagen mixtures with different kinds of CO3Ap contents and porosity were lyophilized into sponges. Scanning electron micrography (SEM) observation of CO3Ap-collagen sponges showed favorable pores for cell invasion. Approximately 50-300 microm size pores appeared to continue through the bulk. Higher magnification of the sponge showed a better adhesion between CO3Ap crystals and collagen. X-ray high-resolution microtomography revealed a clear image of the 3D structure of the sponges. The porosity of 0, 70 and 90%(w/w) CO3Ap-collagen sponges was 79.2 +/- 2.8%, 72.6 +/- 2.4% and 48.9 +/- 6.1%, respectively. The 70%(w/w) CO3Ap-collagen sponge appeared to be the most favorable biomaterial from the viewpoint of natural bone properties. Mouse osteoblast MC3T3-E1 cells were cultured in alphaMEM with 10% FCS for 2 weeks. Hematoxylin-eosin staining confirmed osteoblast cells invaded well into the CO3Ap-collagen sponge. These sponges are expected to be used as hard tissue scaffold biomaterials for therapeutic uses.  相似文献   
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