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81.
Ilkka Havukkala Hideaki Ichimura Yoshiaki Nagamura Takuji Sasaki 《Plant Molecular Biology Reporter》1995,13(1):38-55
A total of 687 DNA sequence accessions from the Mendel database (release 1.04, 3 November 1994) assigned standardized designations
for plant genes and gene products were used in aBLAST similarity search of 7557 rice partial cDNA sequences and 287 other rice sequences from the Japanese Rice Genome Research
Program. We describe procedures for data manipulation, import and export from and to Macintosh and Unix, and the use of 4th
Dimension relational database management system (RDBMS) in data processing. Altogether 275 sequences showed strong similarity
hits. Using the CPGN nomenclature, we assign putative designations for genes and gene products. Assignments include representatives
of 26 gene products, including 58 cDNA sequences similar to α-tubulins (TubA), 23 similar to β-tubulins (TubB) and 51 similar to cytosolic subunit C of glyceraldehyde-3-phosphate dehydrogenase (NAD) (GapC). The results of the similarity searches are listed and are also available electronically. The assignments have been submitted
to the CPGN working groups for verification and for later inclusion in the GenBank/EMBL/DDBJ sequence databases, which will
include the standardized designations in the accession data fields.
Member of the ISPMB Commission on Plant Gene Nomenclature, representing the Rice Genome Research Program of Japan.
Reprint requests to T. Sasaki. 相似文献
82.
Takashi Ueda Yoshihiro Kohli Yoshimichi Abe Takuji Katoh Takeshi Ogasawara Yoshiaki Nojyo Kei Kashima 《Histochemistry and cell biology》1995,103(1):11-17
We evaluated the conditions of fixation for ultrastructurally demonstrating the endogenous peroxidase (PO) activity of macrophages in biopsied human liver. The application of microwaving and immersion fixation with tannic acid and aldehydes allowed excellent visualization of PO activity in the nuclear envelope (NE), rough endoplasmic reticulum (rER), and cytoplasmic granules (CG), with good preservation of cellular ultrastructures. The macrophages with PO activity showed one of the following five patterns of PO localization: positive in both the NE and rER but negative in the CG (type 1); negative in both the NE and rER but positive in the CG (type 2); negative in the NE but positive in both the rER and CG (type 3); positive in all three (type 4); PO negative (type 5). The type 1 cells resembled typical Kupffer cells, type 2 cells monocytes, and type 3 and 4 cells the exudate-resident macrophages considered to be a transitional form between exudate and resident macrophages. Type 5 cells may also be a transitional form between the exudate and resident macrophage, or an end-stage macrophage derived from exudate macrophages which have lost their PO activity. Tannic-acid-aldehyde immersion fixation with microwaving may be a useful method in the study of the PO activities of macrophages in biopsied human liver specimens. 相似文献
83.
Yoshiaki Inayama Izumi Tomiyama Hitoshi Kitamura Yukio Nakatani Takaaki Ito Akinori Nozawa Yasuhiro Usuda Masayoshi Kanisawa 《Histochemistry and cell biology》1995,104(3):191-198
The purpose of this study was to investigate alkaline phosphatase (ALPase) reactivity in rabbit airway epithelial cells. Acetone-fixed, methyl benzoate and xylene-cleared (AMeX-treated) paraffin sections of trachea, bronchus, and lung tissue were stained by an azo dye coupling method for ALPase and examined by light microscopy. Electron histochemical staining was also performed in order to study the sensitivity and specificity of reactivity in each cell type. ALPase reactivity at the light microscopic level was observed exclusively in trachco-bronchial basal cells, and not in bronchiolar basal cells. By electron microscopy, ALPase reactivity was noted in 97.9% of basal cells in the trachea, 97.0% of basal cells in the bronchus, and 94.5% of basal cells and 15.4% of Clara cells in the bronchiole. This was also true for dispersed tracheal epithelial cells. Reactivity was rarely observed in ciliated cells, non-goblet-type secretory cells, and undetermined cells. The reactivity was heatlabile, levamisole-sensitive, and of a non-specific type. These findings indicate that basal cells of rabbit trachea and bonchus have fairly high specificity for ALPase of a non-specific isozyme (92.2% and 95.6%, respectively). Therefore, ALPase is considered to be a useful marker for these cells. 相似文献
84.
85.
Noriyuki Koyama Kazuo Koshiya Yoshiaki Nosoh 《Archives of biochemistry and biophysics》1980,199(1):103-109
ATPase was purified from an alkalophilic Bacillus. The enzyme has a molecular weight of 410,000 and consists of five types of subunits of molecular weights of 60,000 (α), 58,000 (β), 34,000 (γ), 14,000 (δ), and 11,000 (?). The subunit structure is suggested to be α3β3γδ?. The enzyme is activated by Mg2+ and Ca2+. The pH optima of the enzyme with 0.1 and 2.0 mm Mg2+ are 9 and 6, and those with 1 and 10 mm Ca2+ are 8–9 and 7, respectively. Ca2+-ATPase hydrolyzes only ATP, whereas Mg2+-ATPase hydrolyzes GTP and, to a lesser extent, ATP. The values of V and Km of the enzyme with ATP in the presence of 10 mm Ca2+ or 0.6 mm Mg2+ at pH 7.2 are 17 or 0.5 units/mg protein and 1.2 or 0.3 mm, respectively. The enzyme with Mg2+ is appreciably activated by HCO?3. Relationship of the ATPase to the active transport system in the bacterium is suggested. 相似文献
86.
Neuromuscular junctions were formedin vitro between rat spinal cord explants and myotubes. At various intervals after the spinal cord explants were added to the myotube culture (7 hr to 15 days of coculture), the presence of functional neuromuscular junctions was determined by recording miniature endplate potentials (mepps) from the myotubes contacted by a few neurites. Electron microscopical studies were conducted on identified myotubes in which mepps were recorded. Mepps were already found as early as 7 hr after coculture. The fine structure of these newly formed neuromuscular junctions was simple. No synaptic specializations were observed except the presence of a small number of synaptic vesicles in the nerve. The neuromuscular junctions differentiated during the coculture period. Synaptic vesicles formed a cluster at the prejunctional membrane with a localized density in the middle. Basal lamina started to form in 4-day-old cocultures and became continuous in cocultures of 10 days or longer. Clear postjunctional foldings were observed in 15-day-old cocultures. Higher mepp frequencies were correlated with more advanced ultrastructure. 相似文献
87.
88.
M Yamaguchi K Koike Y Yoshimoto H Ikegami A Miyake O Tanizawa 《Endocrinologia japonica》1991,38(4):357-361
The effects of human recombinant interleukin-1 beta and -6 and tumor necrosis factor-alpha (TNF-alpha) on the releases of PRL and dopamine were examined using monolayer cultures of rat pituitary cells and hypothalamic cells. The release of PRL from rat pituitary cells in 30 min was increased about 2-fold (p less than 0.05) by 10(5) U/l interleukin-1 beta, 10(5) U/l interleukin-6 or 100 micrograms/l TNF-alpha. TNF-alpha at 100 micrograms/l significantly increased PRL release within 5 min incubation and this effect continued throughout the next 30 min of incubation. Incubation for 5 min with TNF-alpha caused dose-dependent stimulation of PRL release. These cytokines did not modulate [3H]-dopamine release from primary cultures of hypothalamic cells. These results suggest that these cytokines stimulate PRL release directly at the pituitary gland, without modifying the release of dopamine from the hypothalamus. 相似文献
89.
Drosophila copia protease is likely to be encoded in the gag gene. We have expressed copia gag polyprotein precursor in E. coli. The gag precursor was correctly processed to generate a unique laminate structure in E. coli. The processing was almost completely blocked by a mutation at the putative active site of copia protease, and resulted in accumulation of the precursor. Furthermore, the laminate structure was not found in E. coli expressing the mutant precursor. These results indicate that the protease is involved in cleaving the gag precursor itself. Also, the assembly of copia gag protein should correlate to the autoprocessing of copia gag polyprotein precursor. 相似文献
90.
Fertilizing competency of multiple ovulated eggs in the domestic fowl (Gallus domesticus) 总被引:2,自引:0,他引:2
Fertilizing competency of multiple ovulated eggs in the domestic fowl was examined by fertilization in vitro and early development in culture. Normal laying hens (White Leghorn) were treated with 75 IU of PMSG for 7 days followed by injection of anterior pituitary extracts from chickens (CAPE). Ovulation began to occur 7.5 h after injection of CAPE. These hens ovulated 1-7 ova but some premature ovulation of GV stage ova were observed. In vitro fertilization of the multiple ovulated ova was examined by inseminating 10(6)-10(7) sperm onto the germinal disks in m-Ringer's solution. The gamete or zygote nuclei were detected by DNA specific fluorescence using DAPI (4',6'-diamidino-2-phenylindole) in the histological section prepared from the germinal disk. Process of fertilization was examined in the eggs incubated for 4 h after insemination in DMEM + liquid albumen at 41 degrees C under the atmosphere of 5% CO2 in air. Fertilization rate of the total multiple ovulated eggs was 55% (11/20), in which 90% (9/10) and 10% (1/10) in the eggs recovered 7.5-8.5 h and 9.0-9.5 h after CAPE injection were obtained, respectively. Normal pronuclei were formed in five eggs of those recovered 7.5-8.5 h after CAPE injection. Early development after fertilization in vitro was also examined by incubation for 12 h in DMEM + liquid albumen at 41 degrees C under the atmosphere of 5% CO2 in air. Although development in vitro was delayed compared to that in utero condition, normal development was observed in naturally and multiple ovulated eggs.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献