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81.
The feasibility of precise mapping was investigated noninvasively on the face component in predominantly unilateral primary somatosensory cortices (SI) in six healthy subjects. We recorded somatosensory evoked magnetic fields (SEFs) from the SI and secondary somatosensory cortices (SII) following the electrical stimulation of six skin sites: the infraorbital foramen, the angle of mouth, the upper lip, the lower lip, the mental foramen, and the mandibular angle. The median nerve at the wrist was stimulated as a standard of the map. The location of the equivalent current dipoles (ECDs) estimated from the distribution of magnetic fields was identified on MR images of the brain on each subject. The ECDs of the early components of SEF with peaks of 20-30 ms aligned along the SI in the hemisphere contralateral to the stimulation site. Late components with peaks of 80-150 ms were recorded from the bilateral hemispheres, and their ECDs were identified in the SII of the bilateral hemispheres. There was a distinct separation between the ECD locations representing discrete sites on the face and thumb in the SI of the contralateral hemisphere. Five sites of the face area in SI at the contralateral hemisphere were compatible with the conventional arrangement of homunculus in one subject. However, the remaining subjects had variations in the arrangement. The face area reorganization in the SI is possible to be related to the use-dependent cortical plasticity of the individual or to the perceptual experience by vision and proprioception. 相似文献
82.
Harada K Okano C Kadoguchi H Okubo Y Ando M Kitao S Tamura Y 《International journal of molecular medicine》2003,12(4):621-625
Oxygen-related free radicals have been suggested as a cause of aging and various diseases, for example, various cancers and rheumatoid arthritis. A radical scavenger as an antioxidant has been sought in foods. Fish sauces are traditional Asian fermented seasonings. Using the luminol chemiluminescence method, the peroxyl radical scavenging capability of fish sauces was examined. From the IC50 values, many fish sauces have been shown to have a strong scavenging capability as well as soy sauces. A scavenging mechanism is also proposed. 相似文献
83.
Ohsawa Y Zhang G Kametaka S Shibata M Koike M Waguri S Uchiyama Y 《Archives of histology and cytology》2003,66(4):367-381
A 35 kD protein was isolated and purified from conditioned media of Bcl-2 cDNA-transfected PC12 cells and its cDNA cloned. A database analysis showed that the 35 kD protein is a rat homologue of the human FLRG protein. The biochemical as well as morphological properties of the rat FLRG protein in PC12 cells were examined and its distribution in rat tissues determined. The levels of FLRG mRNA expressed were low during the fetal period, compared with those of follistatin mRNA. The distribution of FLRG and follistatin mRNAs differed from each other after birth; the expression levels of FLRG mRNA were abundant in the adrenal gland and testis, whereas those of follistatin mRNA and activin A were markedly high in the ovary. The presence of FLRG mRNA and/or protein was confirmed in spermatocytes at various differentiating stages andin endocrine cells of both the adrenal cortex and medulla. When overexpressed in PC12 cells, the FLRG protein was found to be stored in secretory granules of the cells and largely secreted by a regulated pathway, while activin A enhancedthe constitutive secretion of the FLRG protein from wild-typpe PC12 cells, indicating that the FLRG protein possesses dualproperties in secretory pathways. The different distribution between FLRG and follistatin mRNA suggests that, like follistatin in the ovary, the FLRG protein may be involved in the maintenance of spermatogenesis in the testis and the growth and function of adrenal tissue cells, probably by regulating the functions of its binding partners such as the TGF-beta ( superfamily members. 相似文献
84.
YMDD mutants in patients with chronic hepatitis B before treatment are not selected by lamivudine 总被引:2,自引:0,他引:2
85.
Summary In vitro CO2 dissociation curves for oxygenated whole blood were determined in 19 healthy male subjects at rest and during submaximal
and maximal bicycle work. Hemoglobin concentration and blood lactate increased with increasing work load and accordingly buffer
value of the whole blood increased while bicarbonate and Base Excess (BE) decreased, resulting in a downward shift of the
CO2 dissociation curve during exercise. Despite the marked increase in buffer values of the blood, the slopes of the CO2 dissociation curves during exercise were found to be about the same as those obtained at rest. It was inferred that the increasing
effect of increased buffer value, on the dissociation slope, was essentially compensated by the decreasing effect of diminished
bicarbonate content. The advantages of this relatively constant CO2 dissociation slope for the indirect measurement of cardiac output by the Fick principle are discussed. 相似文献
86.
Kazuo Nagashima Hisako Endo Koko Sakakibara Yumiko Konishi Ko Miyachi Jau Jinn Wey Yoshiyuki Suzuki Jinichi Onisawa 《Pathology international》1976,26(1):115-132
An autopsy case of a 19-year-old boy who had shown typical gargoyle features, strictly consistent with mucopolysaccharidosis type II (Hunter's syndrome) was reported. Histologically, cytoplasmic vacuolar change was found In hepatocytes, sinusoidal epithelium of spleen, follicular cells of thyroid, Sertoli cells of testis, chromophobe cell of pituitary and generalized fibroblast-like cells including meninges, cardiac valve and periosteum. The vacuoles consisting of membrane-bound structures with flocculus protein-like material and occasional electron dense bodies on electron microscopy, were considered to be the site of mucopolysaccharide deposition by histochemical analysis. Deposition of lipid material consistent with so-called membranous cytoplasmic body was observed in the neurons of central, peripheral and autonomic nervous system. Hepatosplenomegaly could be explained by cytoplasmic deposition, but the cause of cardiomegaly remained further to be studied. Biochemically hepatic mucopolysaccharide was identified as heparan sulfate, while in the kidney dermatan sulfate and heparan sulfate were detected. The correlation between morphology and biochemistry, and between deposition and degeneration was discussed. 相似文献
87.
Toshie Harada Hiromi Kawaminami Noriko N Miura Yoshiyuki Adachi Mitsuhiro Nakajima Toshiro Yadomae Naohito Ohno 《Journal of interferon & cytokine research》2006,26(4):235-247
SCG is a major 6-branched 1,3-beta-D-glucan in Sparassis crispa Fr. showing antitumor activity. We recently found that the splenocytes from naive DBA/1 and DBA/2 mice are potently induced by SCG to produce interferon- gamma (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-12p70 (IL-12p70), and that GM-CSF plays a key biologic role among these cytokines. In this study, we investigated the contribution of cell-cell contact and soluble factors to cytokine induction by SCG in DBA/2 mice. Cell-cell contact involving intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) was an essential step for the induction of GM-CSF and IFN-gamma by SCG but not for the induction of TNF-alpha or IL-12p70 by SCG. SCG directly induced adherent splenocytes to produce TNF-alpha and IL-12p70. GM-CSF was required for the induction of TNF-alpha by SCG, and in turn, TNF-alpha enhanced the release of GM-CSF and thereby augmented the induction of IL-12p70 and IFN-gamma by SCG. Neutralization of IL-12 significantly inhibited the induction of IFN-gamma by SCG. We concluded that induction of GM-CSF production by SCG was mediated through ICAM-1 and LFA-1 interaction, GM-CSF subsequently contributed to further cytokine induction by SCG, and reciprocal actions of the cytokines were essential for enhancement of the overall response to SCG in DBA/2 mice. 相似文献
88.
Arpp,a new homolog of carp,is preferentially expressed in type 1 skeletal muscle fibers and is markedly induced by denervation 总被引:3,自引:0,他引:3
Tsukamoto Y Senda T Nakano T Nakada C Hida T Ishiguro N Kondo G Baba T Sato K Osaki M Mori S Ito H Moriyama M 《Laboratory investigation; a journal of technical methods and pathology》2002,82(5):645-655
In this study, we isolated and characterized a murine counterpart of the human Arpp (hArpp) gene. Sequence analysis revealed that the murine Arpp (mArpp) gene is almost identical to the Ankrd2 gene, which has recently been isolated as a mouse gene induced in stretched skeletal muscle. The mArpp gene encodes a protein of 332 amino acids that contains four well-conserved ankyrin-repeat domains in the central portion of the protein. The amino acid sequence of mArpp protein (mArpp) is highly homologous to that of mouse cardiac-restricted ankyrin-repeat protein (Carp), which is proposed to be a putative genetic marker for cardiac hypertrophy. Immunohistochemical analysis revealed that mArpp is preferentially expressed in type 1 skeletal muscle fibers, and that mArpp is localized in both the nucleus and the sarcomeric I-band of muscle fibers, suggesting that Arpp may function as a nuclear and sarcomeric protein. Furthermore, mArpp was also expressed in neurons of the cerebellum and cerebrum, the islets of Langerhans in the pancreas, and the esophageal epithelium, suggesting that mArpp may play a functional physiologic role in brain, pancreas, and esophagus as well as in type 1 muscle fibers. Interestingly, although mArpp was localized in both nucleus and cytoplasm in neurons, its localization was restricted to nucleus in pancreas and esophagus, suggesting that intracellular localization of mArpp is regulated in a tissue-specific manner. Furthermore, we found that mArpp- and Carp-expression in skeletal muscle were markedly up-regulated after denervation. Although the elevated expression level of Carp was kept only for two weeks after denervation, that of Arpp was kept at least for 4 weeks, suggesting that mArpp and Carp may play distinct functional roles in denervated skeletal muscle. 相似文献
89.
Yoshiyuki Nagai Michinari Hamaguchi Koichiro Maeno Masao Iinuma Toshisada Matsumoto 《Virology》1980,102(2):463-467
To investigate the relationship between the pathogenicity of Newcastle disease virus and the structure of viral proteins, two typical strains were sampled from each of three groups of different pathogenicities and these six strains were compared for protein structure by sizing peptides generated by partial digestion with Staphylococcus aureus V8 protease and chymotrypsin. These digests yielded closely similar peptide patterns for the internal polypeptides L and NP, whereas those of the glycoproteins HN and F showed apparent variations which appeared to be specific for the individual groups. Although not as significant as in the glycoproteins, group-dependent variations were also detectable with the M protein. These results suggest that the external proteins might undergo considerable changes whereas the internal proteins would be highly stable and that there is a definite correlation between such changes in the external proteins and the pathogenicity of the virus. 相似文献
90.
Lee H Tsukiya T Homma A Kamimura T Takewa Y Nishinaka T Tatsumi E Taenaka Y Takano H Kitamura S 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2004,50(3):205-210
Recently, cavitation on the surface of mechanical heart valves has been studied as a cause of fractures occurring in implanted mechanical heart valves. The cause of cavitation in mechanical heart valves was investigated using the 25 mm Medtronic Hall valve and the 23 mm Omnicarbon valve. Closing of these valves in the mitral position was simulated in an electrohydraulic totally artificial heart. Tests were conducted under physiologic pressures at heart rates from 60 to 100 beats per minute with cardiac outputs from 4.8 to 7.7 L/min. The disk closing motion was measured by a laser displacement sensor. A high-speed video camera was used to observe the cavitation bubbles in the mechanical heart valves. The maximum closing velocity of the Omnicarbon valve was faster than that of the Medtronic Hall valve. In both valves, the closing velocity of the leaflet, used as the cavitation threshold, was approximately 1.3-1.5 m/s. In the case of the Medtronic Hall valve, cavitation bubbles were generated by the squeeze flow and by the effects of the venturi and the water hammer. With the Omnicarbon valve, the cavitation bubbles were generated by the squeeze flow and the water hammer. The mechanism leading to the development of cavitation bubbles depended on the valve closing velocity and the valve stop geometry. Most of the cavitation bubbles were observed around the valve stop and were generated by the squeeze flow. 相似文献