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781.
Localization of silver grains detected by the silver-impregnation method, a technique used to detect the classical Golgi apparatus, was examined with light and electron microscopy. Two types of silvered images of the Golgi apparatus were compared; each was obtained by Da Fano 's silver-impregnation method, and one was modified with Caulfield 's fixative during the preliminary fixation. Under ordinary light microscopy the images were very similar and showed the duplex structure of the Golgi apparatus which consists of an argentophil wall and argentophobe core. With electron microscopy, the relationship between the fine structure of the Golgi complex and the silver deposits was obtained in greater detail by the latter technique because the fine structure of the Golgi complex was retained. Many fine silver grains were detected in the cytoplasm adjacent to the Golgi complex, but none were present in the Golgi cisternae. This suggests that the argentophil wall of the duplex structure of the classical Golgi apparatus may be formed from argentophil substances that locate in the cytoplasm adjacent to the Golgi lamellae, and that the argentophobe core may be related to the Golgi lamellae. 相似文献
782.
Koichi Hagiwara Katsuya Ogata Naruhito Hironaga Shozo Tobimatsu 《Somatosensory & motor research》2020,37(3):222-232
AbstractPurpose: Temporal-structure discrimination is an essential dimension of tactile processing. Exploring object surface by touch generates vibrotactile input with various temporal dynamics, which gives diversity to tactile percepts. Here, we examined whether slow cortical potential shifts (SCPs) (<1?Hz) evoked by long vibrotactile stimuli can reflect active temporal-structure processing.Materials and methods: Vibrotactile-evoked magnetic brain responses were recorded in 10 right-handed healthy volunteers using a piezoelectric-based stimulator and whole-head magnetoencephalography. A series of vibrotactile train stimuli with various temporal structures were delivered to the right index finger. While all trains consisted of identical number (15) of stimuli delivered within a fixed duration (1500?ms), temporal structures were varied by modulating inter-stimulus intervals (ISIs). Participants judged regularity/irregularity of ISI for each train in the active condition, whereas they ignored the stimuli while performing a visual distraction task in the passive condition. We analysed the spatiotemporal features of SCPs and their behaviour using the minimum norm estimates with the dynamic statistical parametric mapping.Results: SCPs were localized to contralateral primary somatosensory area (S1), contralateral superior temporal gyrus, and contralateral as well as ipsilateral secondary somatosensory areas (S2). A significant enhancement of SCPs was observed in the ipsilateral S2 (S2i) in the active condition, whereas such effects were absent in the other regions. We also found a significant larger amplitude difference between the regular- and irregular-stimulus evoked S2i responses during the active condition than during the passive condition.Conclusions: This study suggests that S2 subserves the temporal dimension of vibrotactile processing. 相似文献
783.
Preparative separation of derivatives of amino acid enantiomers was carried out by a countercurrent gas–liquid chromatography (CCGLC) with chiral liquid phases, N-stearoyl-L -valine tert-butylamide and/or N-stearoyl-L -leucine tert-butylamide. In order to make effective use of these phases and also to lower the viscosity, Apiezon C was added as diluent. Through a repeated operation of a temperature gradient, purities more than 99% of leucine and α-amino butyric acid derivatives were proved to be obtained. © 1993 Wiley-Liss, Inc. 相似文献
784.
Guo Quan Zhang Ho To Tsuyoshi Yamaguchi Hideto Fukushi Katsuya Hirai 《Microbiology and immunology》1997,41(11):871-877
The gene (com1) encoding a 27-kDa outer membrane protein in 21 strains of Coxiella burnetii from a variety of clinical and geographical sources was sequenced for strain differentiation. The com1 gene was highly conserved among all the strains tested but there were several differences in nucleotide and deduced amino acid sequences. Based on the com1 gene-specific nucleotides and deduced amino acids, the 21 strains were divided into four groups. Group 1 contained 14 strains originating from ticks, cattle and human cases of acute Q fever. Groups 2 and 3 included 2 and 3 strains, respectively, originating from human cases of chronic Q fever. Group 4 contained 2 strains originating from a human case of acute Q fever and a goat with abortion. The results indicated that the strains originating from ticks, cattle and human cases of acute Q fever differed at the molecular level from those of human chronic Q fever. This study suggests that a sequence analysis of the com1 gene can be used for strain differentiation of C. burnetii. 相似文献
785.
Near-UV Irradiation Induces Shock Proteins in Anacystis nidulans R-2; Possible Role of Active Oxygen
Anacystis nidulans R-2 cells were irradiated with near-UV light(295390 nm) at an intensity that resulted in 3040%survival. The near-UV light induced the preferential synthesisof sixteen proteins, which were designated UV-shock proteins.Several UV-shock proteins were also induced by heat shock (42?C)and six were synthesized by treatment with methyl viologen.The water-soluble fraction prepared from the cells generatedsuperoxide anion radicals upon irradiation with near-UV light,suggesting the production of active species of oxygen in cellsas a result of exposure to near-UV light. (Received February 18, 1991; Accepted May 24, 1991) 相似文献
786.
Although phytochrome is known to regulate gene expression inplants, the location of the phytochrome molecules involved inthe response remains unclear. Thus the aim of this investigationwas to test the possibility that nuclei contain phytochrome.Nuclei were isolated from dark-grown pea (Pisum sativum cv.Alaska) plumules in the dark and the nuclear proteins were resolvedon SDS polyacrylamide gels and transferred to nitrocelluloseby western blotting. A significant amount of phytochrome wasdetected in the nuclear proteins by immunostaining using monoclonaland polyclonal anti-phytochrome antibodies. Most of the phytochromeassociated with the nuclei could not be removed by treatmentwith high salt and low magnesium, indicating that the bindingwas rather stable. However, the isolation of nuclei in the presenceof exogenously added [125I]phytochrome of PR form in the darksuggested that significant amount of the phytochrome detectedin the nuclei was derived from contamination by the solublefraction during isolation. It is an open question as to whether,besides this contaminated phytochrome, isolated nuclei endogenouslycontain very small amount of phytochrome.
4Present Address: Plant Molecular Biology and Biochemistry ResearchGroup, Departments of Biochemistry and Botany, University ofGlasgow, Glasgow G12 8QQ, U.K. (Received February 8, 1988; Accepted July 27, 1988) 相似文献
787.
In an attempt to identify domains directly involved in the signal transduction of phytochrome B (phyB), we over-expressed the achromophoric C-terminal half of phyB under control of the CaMV-35S promoter in transgenicArabidopsis. In three independent transgenic lines, we detected accumulation of the introduced protein of predicted size at levels higher than that of the endogenous phyB by immunoblot analysis. Although these transgenic plants did not show any phenotype in the dark, enhancement of the phyB-dependent inhibition of hypocotyl elongation and reduction of the phytochrome A (phyA)-dependent inhibition were observed. 相似文献
788.
Satoshi Katayama Toshinori Ishida Katsuya Goto Keiki Iizuka Keishiro Karita 《Ichthyological Research》2002,49(1):81-84
A new aging method, fluorescent observation of burnt otoliths, was discovered to disclose the age and growth of the conger
eel. Under UV light, bright fluorescent zones were visible in the burnt otolith but not in the unburnt otolith. An illumination
wavelength around 380 nm was found to be suitable for fluorescence observation of burnt otoliths. Bright zones of the conger
eel otolith formed around June–August in Sendai Bay and were validated as annuli. The conger eels caught by net pot fishery
were found to be mainly aged from 1+ to 4+ years.
Received: March 7, 2001 / Revised: September 12, 2001 / Accepted: October 10, 2001 相似文献
789.
Yasunori Ohba Hitoshi Kitagawa Katsuya Kitoh Sachiyo Asahina Kaori Nishimori Kazuhiro Yoneda Tetsuo Kunieda Yoshihide Sasaki 《Mammalian genome》2000,11(4):316-319
Renal tubular dysplasia is a hereditary disease of Japanese black cattle showing renal failure and growth retardation with
an autosomal recessive trait. In the present study, we mapped the locus responsible for the disease (RTD) by linkage analysis with an inbred paternal half-sib pedigree obtained from commercial herds. By analyzing segregation of
microsatellite markers in the half-sibs, significant linkage was observed between the RTD locus and markers on bovine Chromosome (Chr) 1 with the highest lod score of 11.4. Homozygosity mapping with the inbred pedigree
further defined the localization of the RTD locus in a 4-cM region between microsatellite markers BMS4003 and INRA119. Mapping of the RTD locus on bovine Chr 1 will facilitate cloning and characterization of the gene responsible for this disease.
Received: 24 September 1999 / Accepted: 14 December 1999 相似文献
790.