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1.
N. Wada Y. Kanda M. Tokuriki K. Kanda 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2000,186(7-8):771-779
We studied neuronal pathways from low-threshold muscle (group I, II) and cutaneous afferents (group A(alpha)beta) innervating the tail to motoneurons innervating trunk muscles (m. iliocostalis lumborum and m. obliquus externus abdominus) in 18 spinalized cats. Stimulation of group I muscle afferents produced excitatory postsynaptic potentials or excitatory postsynaptic potentials followed by inhibitory postsynaptic potentials in all motoneurons innervating the m. iliocostalis lumborum which showed effects (32%), and predominantly inhibitory postsynaptic potentials in motoneurons innervating the m. obliquus externus abdominus (47%). Stimulation of group I+II afferents produced significant increases of the incidence of motoneurons showing postsynaptic potentials (the notoneurons innervating the m. iliocostalis lumborum, 87%; the motoneurons innervating the m. obliquus externus abdominus, 82%). The effects of low threshold cutaneous afferents were bilateral, predominantly producing inhibitory postsynaptic potentials in motoneurons innervating both muscles. These results suggest that neuronal pathways from muscle afferents to back muscle motoneurons mainly increase the stiffness of the trunk to maintain its stability, while those to abdominal muscles help to extend the dorsal column by decreasing their activities. The results also indicate that neuronal pathways from cutaneous afferents to trunk motoneurons functionallY disconnect the tail from the trunk. 相似文献
2.
A possible metabolic activation pathway of benzenein vivo is the nonenzymatic oxidation of hydroquinone producedvia the cytochrome P-450-mediate two-step oxidation of benzene. The mechanism of the further oxidation of hydroquinone and the nature of the most reactive intermediate have not yet been clarified, although it is speculated that the intermediate isp-benzoquinone and/orp-benzosemiquinone. The theoretical result of using molecular orbital calculations (ab initio and CNDO/2 methods) indicates that although the mechanism of the nonenzymatic oxidation of hydroquinone cannot yet be determined, the intermediate is thep-benzosemiquinone anion radical. It is also suggested that active-oxygen species such as hydroxyl radical, which accelerates the nonenzymatic oxidation, play an important role in the metabolic pathway in question. 相似文献
3.
S Kanda 《Zeitschrift für Morphologie und Anthropologie》1989,77(3):227-233
Cephalometrical configurations of Japanese people were investigated on two hundred and sixteen groups living on the four main islands of Japan: Hokkaido, Honshu, Shikoku, and Kyushu. The Japanese in Honshu were divided geographically into a narrow-featured eastern major group and a broad-featured western major group. A physical characteristic of Japanese living in the western mid-Honshu was the lengthened feature of their cephalic measurement, an influence of a long-headed group of Korean people; Japanese residents in eastern mid-Honshu, however, showed the result of mixing with a short-headed group of Korean people. Japanese people living in Hokkaido, the northernmost island, and in the Ryukyu Islands in the South of Japan, presented no important finding which suggests their influence on the physical characteristics of the Japanese. Ongoing studies indicating physical relationships between Kyushu or Shikoku residents and Honshu residents, are as yet insufficient. 相似文献
4.
K Sobue K Kanda I Miyamoto K Iida I Yahara R Hirai A Hiragun 《Experimental cell research》1989,181(1):256-262
With fluorescence and interference reflection microscopy (IRM), we compared the regional distribution of calspectin, its interacting proteins (nonerythroid protein 4.1 and calpactin), alpha-actinin, and vinculin in NRK cells and their avian sarcoma virus (ASV)- or temperature-sensitive (ts) Rous sarcoma virus (RSV)-transformed cells. The localization of these cytoskeletal proteins was determined with the specific antibodies. In NRK cells, alpha-actinin and vinculin were concentrated at adhesion plaques. By contrast, calspectin was distributed throughout the cytoplasm, but not concentrated at adhesion plaques. In ASV- and ts RSV-transformed cells, all three cytoskeletal proteins were concentrated at dot structures representing cellular feet. Nonerythroid protein 4.1 and calpactin were diffusely distributed throughout the cytoplasm of NRK cells and their transformed counterparts. In the case of calpactin, a part of this protein was excluded near regions of the terminal ends of stress fibers. These two proteins did not show the restricted location at the dot structures of transformed cells. From these findings, it is apparent that the accumulation of calspectin into dot structures is a specific event for cell transformation induced by the src protein. 相似文献
5.
Crude extracts of mycelia and basidiocarp primordia in the basidiomycete Coprinus cinereus were resolved on sodium dodecyl sulfate--polyacrylamide gels, and ubiquitin and several proteins were detected by immunoblotting with anti-ubiquitin antibody. The molecular masses of the proteins detected were 30,900, 28,600, 27,800, 26,300, 22,500, and 15,400 daltons, respectively. Relative levels of ubiquitin and most of the ubiquitin-immunoreactive proteins in basidiocarp primordium formation increased and in basidiocarp maturation decreased in cap and upper stipe, while in lower stipe became high except for the 27,800 dalton protein and ubiquitin. During sporulation, ubiquitin and all the ubiquitin-immunoreactive proteins tended to decrease in the cap of the young wild-type basidiocarp. The levels of 30,900 and 15,400 dalton proteins increased transiently at 6-10 h after the beginning of the last light period, while ubiquitin decreased markedly. No correlation was observed between changes in levels of the ubiquitin-immunoreactive proteins and the blocked stages in sporulation-deficient mutants. 相似文献
6.
J Hanai M Lin A Wada S Ishiguro T Miki H Sakaguchi H Kanda 《Histology and histopathology》1992,7(4):533-541
Distribution of intermediate filament proteins (IFs) and several special markers was studied in 39 testicular germ cell tumors and 8 embryos and foetuses. The similarity and difference between development of germ cell tumor and embryogenesis were immunohistochemically investigated. Seminoma and embryonal carcinoma, as tumoral counterparts of undifferentiated germ cells, were characterized by little IF expression. This study revealed that the maturing and differentiating process in germ cell tumor is different from normal embryonal development and the tumor cells showed leaping maturing steps in tumorigenesis. Immunostaining for IFs helped to discover the further differentiation occurring in embryonal carcinoma and to demonstrate heterogeneous elements in non-seminoma germ cell tumors, which sometimes might not be apparent by light microscopical observation of H&E staining section. According to the findings, two patterns in mixed germ cell tumors are suggested; i.e., combined and diffuse types. The mechanism of tumorigenesis of the two types is supposed to be different. Clinically, the prognosis of most patients with testicular germ cell tumor is fairly good because of the improved chemotherapies that are dependent on histological diagnosis. 相似文献
7.
8.
The developmental process of the testis and age-related changes in the morphology of rete testicular spermatozoa were investigated in Meishan boars at 1 to 364 days of age. Testicular weight and the diameter of seminiferous tubules increased rapidly until 150 to 180 days of age. Leptotene stage spermatocytes, round spermatids and spermatozoa were first found in the section of seminiferous tubules at 30 to 45, 60 and 75 days of age, respectively. However, after 105 to 120 days of age, most rete testicular spermatozoa were morphologically normal. These results indicate that Meishan boars reach puberty as early as 75 days of age, though the testes acquire the ability to produce morphologically normal spermatozoa at about 120 days. 相似文献
9.
Synthesis of polyamide supports for use in peptide synthesis and as peptide-resin conjugates for antibody production. 总被引:3,自引:0,他引:3
P Kanda R C Kennedy J T Sparrow 《International journal of peptide and protein research》1991,38(4):385-391
We have synthesized beaded, hydrophilic cross-linked, aminoalkyl polydimethylacrylamide supports upon which peptides have been assembled using standard Boc or Fmoc chemistry in automated equipment. The resins were prepared by the free radical-initiated co-polymerization of N,N-dimethylacrylamide, N,N'-bisacrylyl-1,3-diaminopropane, and a functional monomer which were contained in a reverse-phase, detergent-emulsified suspension. The functional monomers used were N-(2-(methylsulfonyl)ethyloxycarbonyl)-allyl-amine (MSC-allylamine), N-acrylyl-1,6-diaminohexane hydrochloride or N-methacrylyl-1,3-diamino-propane hydrochloride. The MSC protecting group was removed by treatment of the resin with methanolic base during workup. After coupling of N-alpha-t-butyloxycarbonyl-alanine (Boc-alanine), amino acid analyses gave resin loading capacities between 0.15 mmol/g and 1.4 mmol/g, depending on the concentration and composition of the functional monomer. The resulting polymers were highly swollen by polar solvents including aqueous buffers. Peptides were synthesized on these supports after attaching the first amino acid directly or through a cleavable ester linker. When the carboxyl-terminal amino acid was coupled as the 4-oxymethylbenzoic acid derivative, the peptide could be deprotected and remain attached to the hydrophilic polymer since the peptide-benzyl ester bond was stable to HF deprotection at 0 degrees in the presence of 10% anisole and 1% ethanedithiol. The resulting peptidyl-resin could be swollen in aqueous buffers and injected into animals for the production of antibodies. 相似文献
10.
Cervicovaginal and endometrial cytology in ovarian cancer 总被引:1,自引:0,他引:1
The clinical significance of cytologic examination was studied in 114 patients with ovarian cancer who had received preoperative cytologic examinations. The overall positive rate of the cytologic examinations was 26.3% (30 of 114): 22 (19.3%) of the 114 cases had positive cervicovaginal smears while 13 of 31 endometrial aspiration smears (41.9%) were positive. The positive rate was not related to the volume of ascites but rather to its presence or absence. Thus, if ascites was observed, the positive rate was about 2.1 times higher than if it was absent. In two of four cases of ovarian cancer with no endometrial invasion but a positive cytologic examination of ascitic fluid, fallopian tube specimens contained cancer cells; this suggests that ovarian cancer cells may reach the cervix and/or vagina by passing through the fallopian tube, particularly if ascites is present. Since cytologic examination, especially of endometrial aspiration smears, shows a high positive rate if ovarian cancer cells are observed in the abdominal cavity, cytology should be used as an important ancillary method for the assessment of ovarian cancer. 相似文献