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排序方式: 共有557条查询结果,搜索用时 31 毫秒
1.
Masanori Shinzato Mikihiro Shamoto Satoru Hosokawa Chiyuki Kaneko Akido Osada Miyuki Shimizu Asako Yoshida 《Biotechnic & histochemistry》1995,70(3):114-118
The present study shows that Langerhans cells can be differentiated from Interdigitating cells at the light microscopic level. Superficial lymph nodes and skin taken from necropsies and the lymph nodes of dermatopathic lymphadenopathy (DPL) were used for this experiment. Sections of lymph node and skin were embedded using the acetone, methyl benzoate and xylene (AMeX) method and dendritic cells were immunostained with anti S-100 protein antibody (S-100, and OKT-6 (CD1a) using the restaining method. Langerhans cells in the skin were positive for both CD1a and S-100. Dendritic cells positive for both CD1a and S-100, and dendritic cells positive for S-100, but not for CD1a were observed in superficial lymph nodes. In normal superficial lymph nodes, there were more interdigitating cells than Langerhans cells. The majority of the dendritic cells in the DPL were Langerhans cells. We conclude that the S-100 and CD1a positive cells are Langerhans cells, and the S-100 positive-CD1a negative cells are interdigitating cells. 相似文献
2.
The membrane viscosity of peripheral blood lymphocytes (PBLs) of equine, bovine and canine was measured by the use of time-resolved fluorescence depolarization technique with 1, 6-diphenyl-1,3,5-hexatriene (DPH). The viscosity values were 0.55, 0.59 and 0.50 poise for equine, bovine and canine PBLs, respectively. These values were compared with steady-state anisotropies and order parameters measured from electron spin resonance (ESR) of 5-doxyl stearic acid. Both values were increased with increase of viscosity. The fluid property of the membranes stimulated with phytohemagglutinin-P (PHA) was measured with steady-state fluorescence anisotropy and ESR. Little change of membrane fluidity was recognized with both methods during the stimulation with PHA. It appears that PHA activation process for these lymphocytes does not included large increase of the membrane fluidity which significantly accelerate the diffusion velocity of receptors in the plasma membrane. 相似文献
3.
Kazumasa Matsuki M.D. Hiroo Maeda Takeo Juji Hidetoshi Inoko Asako Ando Kimiyoshi Tsuji Yutaka Honda 《Immunogenetics》1988,27(2):87-90
Taq I-generated HLA-DQrestriction fragment length polymorphism was examined in Japanese patients with narcolepsy. All patients were DR2 positive and shared a 6.0 kb fragment, although this fragment was found only in 54 % of the healthy DR2-positive Japanese. This finding added the DQ
gene to the list of candidates for the possible narcolepsy-susceptibility gene. In contrast, there was no complete association between narcolepsy and DXrestriction fragment length polymorphism. These findings suggest that a narcolepsy-susceptibility gene is located closer to the DQ locus than to the DX locus. 相似文献
4.
The effect of minaprine (3-(2-morpholinoethylamino)-4-methyl-6-phenylpyridazine) on the K+ channels was studied by means of 42K efflux from rat brain synaptosomes, comparing the effects of 4-aminopyridine and 9-amino-1,2,3,4-tetrahydroacridine (THA). 42K efflux from rat brain synaptosomes was classified into five components: a resting component (R), a rapidly inactivating, voltage-dependent component (T), a slowly inactivating, voltage-dependent component (S) and a voltage-dependent, Ca(2+)-dependent component which is divided into a fast phase (CT) and a slower phase (CS). 4-Aminopyridine selectively inhibited 42K efflux of component T. THA blocked both S and T components. The inhibitory effect of THA on the 42K efflux of component S was quite pronounced compared with that of component T. Minaprine inhibited the 42K efflux of components S and T but the inhibitory effect on component S was observed with a lower dose of minaprine than that needed for the effect on component T. Minaprine had no effect on the Ca(2+)-dependent component while THA blocked component CT. 42K efflux of the resting component was not changed by minaprine, THA or 4-aminopyridine. These results suggest that minaprine blocks Ca2+ independent voltage-dependent K+ channel is involved in the pharmacological actions of minaprine. 相似文献
5.
Molecular Genetic Analysis of Myelin-Deficient Mice: Shiverer Mutant Mice Show Deletion in Gene(s) Coding for Myelin Basic Protein 总被引:17,自引:6,他引:11
6.
Purple membrane from Halobacterium halobium in suspensions has been studied by quasielastic light scattering. The intensity correlation functions of polarized scattered light were measured at various K2 values (K being the magnitude of the scattering vector), and the first cumulant Gamma of the field correlation function G1(tau) was obtained by a cumulant expansion method. The apparent diffusion coefficient Gamma /K2 did not increase monotonically with K2 values and showed a distinct anomaly in an intermediate range of K. A theoretical formulation of G1(tau) for a disc and an extremely oblate ellipsoidal shell of revolution (S. Fujime and K. Kubota, Biophys. Chem. 23 (1985) 1) was applied to the analysis of the spectra, and characteristic features of experimental spectra were well reproduced. It was suggested that a strong interference effect between scattered rays on Gamma /K2 should be attributed to a slight noncircular shape of the purple membrane and that a contribution to Gamma /K2 from membrane flexibility should be taken into account. This study will provide experimental evidence of the feasibility of membrane studies by dynamic light scattering. 相似文献
7.
Sodium-dependence of glycylglycine (Gly-Gly) influx and stimulation of Na+ transport by Gly-Gly were studied in everted sacs, sheet preparations and brush-border membrane vesicles isolated from guinea-pig ileum. Gly-Gly influx was found to be independent of the presence of Na+, while Na+ transport was stimulated by Gly-Gly as evidenced by increases in transmural potential difference (PDt), short-circuit current (Isc) and Na+ influx. The change in PDt (ΔPDt) induced by Gly-Gly was a saturable function of Gly-Gly concentration, showing a Michaelis-Menten type relationship. The half-saturation concentration for Gly-Gly estimated from the electrical data was nearly identical with that estimated from influx data. At a constant Gly-Gly concentration the relationship between Isc and Na+ concentration was sigmoid, and the Hill coefficient was 1.5. Kinetic analysis according to Garay Garrahan indicates that each Gly-Gly carrier has two equivalent non-interacting binding sites for Na+, and that translocation of Na+ occurs when the two Na+ sites on the carrier loaded with Gly-Gly are occupied by Na+. However, our results indicate that the resultant Na+ flow is not capable of stimulating Gly-Gly translocation. 相似文献
8.
Biosynthesis of the two halobacterial light sensors P480 and sensory rhodopsin and variation in gain of their signal transduction chains. 总被引:5,自引:5,他引:0 下载免费PDF全文
The two retinal-containing photoreceptors of halobacteria, P480 and sensory rhodopsin, are formed constitutively and inducibly, respectively. Both photoreceptors are synthesized as apoproteins in cells with nicotine-inhibited retinal synthesis and are reconstituted as chromoproteins by the addition of all-trans retinal to cell membrane preparations. The decrease in photoreceptor-mediated photophobic response at the stationary growth phase of cells is not due to photoreceptor degradation but due to a deficiency of the signal transduction chain in the cell. 相似文献
9.
Bacteriorhodopsin mutants of Halobacterium sp. GRB. II. Characterization of mutants 总被引:11,自引:0,他引:11
J Soppa J Otomo J Straub J Tittor S Meessen D Oesterhelt 《The Journal of biological chemistry》1989,264(22):13049-13056
The bacterioopsin genes of Halobacterium sp. GRB (Ebert, K., Goebel, W., and Pfeifer, F. (1984) Mol. & Gen. Genet. 194, 91-97) wild type and 10 independent mutants of different phenotypes have been cloned and sequenced. The wild type gene has two conservative changes compared to the gene of Halobacterium halobium, so that the proteins of the two species are identical. Six different mutations at five different codons have been found, leading to the following amino acid changes compared to the wild type: Trp10----Cys (three cases), Tyr57----Asn, Asp85----Glu, Asp06----Asn (three cases), Asp96----Gly, Trp138----Arg. A first characterization of the mutant proteins is given, and their implications for models of bacteriorhodopsin structure and function are discussed. 相似文献
10.
Koichiro Yoshihara Motokatsu Tsuyuki Asako Itaya Yasuharu Tanaka Tomoya Kamiya 《Molecular and cellular biochemistry》1994,135(2):143-151
HL-60 cells transferred from serum-supplemented to serum-free culture medium initially bound to culture plate tightly and then released from the plate on increasing the culture time and resumed exponential growth after about 8 h lag. At the initial stage of the culture, the cells became extremely sensitive to 3-aminobenzamide, a potent inhibitor of poly (ADP-ribose) polymerase, and, at 1 mM, 80 to 90% of the cells were lysed within 20 h, whereas the inhibitor was totally ineffective on the cell growth in serum-supplemented medium at the concentration. Non-inhibitory analogs of the inhibitor were ineffective. Assay of poly(ADP-ribose) polymerase activity in permeable cells indicated that a transient activation of the enzyme occurred during the culture in serum-free medium (the maximum activation was observed at 8 h of the culture). The cells conditioned in serum-free medium for 24 h acquired significant resistancy to the inhibitor. A low concentration of fibronectin (5 to 10/ml) and a relatively high concentration of bovine serum albumin (0.5 to 1 mg/ml) effectively blocked the cell attachment to plate and also the 3-aminobenzamide-induced cell lysis. These results suggest that poly(ADP-ribose) polymerase is involved in a process essential for HL-60 cells to adapt to a serumdeprived growth condition. 相似文献