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1.
T Nimura M Okada M Shimizu M Kawabe T Itoh M Iwasaki H Kimura T Takeuchi 《The Annals of physiological anthropology》1990,9(4):329-333
Motorcyclists who work in some offices sometimes complained of coldness, pain and numbness of upper limbs. We studied how to discriminate between vibration syndrome and local fatigue of the motorcyclists. Subjects are 42 motorcyclists of an office in Aichi prefecture. 25 of them held several letters in their left hand when they delivered the letters. They complained of coldness, pain and numbness in the left upper limbs more than in the right limbs (p less than 0.01). We think that it is the local fatigue rather than the disorder of vibration syndrome that causes such symptoms. So it is very important to recognize the existence of local fatigue in order to know how to discriminate between vibration syndrome and local fatigue of the motorcyclists. 相似文献
2.
Purification and Characterization of Sucrose Synthase from Peach (Prunus persica) Fruit 总被引:4,自引:0,他引:4
Sucrose synthase (EC 2.4.1.13
[EC]
) was purified from peach fruit(Prunus persica) to a single band of protein on SDS-PAGE byammonium sulfate fractionation, DEAE-cellulose (DE-52) chromatography,Sepharose CL-6B gel filtration, PBA-60 affinity chromatographyand Sephadex G-200 gel filtration. The molecular weight wasestimated to be 360,000 by gel filtration. The enzyme was foundto be a tetramer of identical 87-kDa subunits. The maximum activityfor the synthesis and cleavage of sucrose was observed at pH8.5 and pH 7.0, respectively. The enzymatic reaction followedtypical Michaelis-Menten kinetics in both directions, with thefollowing parameters: Km(fructose), 4.8 mmM; Km(UDPglucose),0.033 mM; Km(sucrose), 62.5 mM; Km(UDP), 0.080 mM. Other properties,such as substrate specificity and the effects of divalent cations,were also investigated. The relationship between the enzymeand the accumulation of sucrose in peach fruit is discussed.
Present address: Laboratory of Horticulture, Faculty of Agriculture,Nagoya University, Chikusa, Nagoya 464, Japan. (Received May 2, 1988; Accepted September 14, 1988) 相似文献
3.
Properties of the Escherichia coli RuvA and RuvB proteins involved in DNA repair, recombination and mutagenesis 总被引:4,自引:0,他引:4
The ruvA and ruvB genes constitute an operon, which is regulated by the SOS system and involved in DNA repair, recombination and mutagenesis. RuvA protein binds to both single-stranded and double-stranded DNA. RuvB protein has weak ATPase activity. RuvA bound to DNA greatly enhances ATPase activity of RuvB. UV-irradiation to supercoiled DNA further enhances the stimulatory effect of RuvA on the RuvB ATPase activity. In the presence of ATP the RuvA-RuvB complex has an activity that renatures cruciform structures formed by heating and gradually cooling supercoiled DNA with an inverted repeat. These findings suggest that the RuvA-RuvB complex interacts with an irregular conformation in damaged DNA and induces conformational changes in DNA using energy provided by ATP hydrolysis, so that it facilitates DNA repair, recombination and error prone replication. 相似文献
4.
I. Nakasono M. Iwasaki M. Ogata T. Yoshitake K. Narita S. Kubo H. Suyama Y. Tanoue 《Human genetics》1985,70(1):84-85
Summary A new single band variant (Gc Ar) or the Gc subtypes not identical with the known Gc variants has been detected in the plasma of a healthy blood donor by isoelectric focusing. Using this technique the variant is represented by a single band which has a similar isoelectric point to the Gc 1C2 anodal band. It is well known that the single band Gc phenotypes remain unaltered after neuraminidase treatment. Nevertheless, the new single band variant (Gc Ar) is altered after neuraminidase treatment as is Gc 2A3. After neuraminidase treatment, the Gc Ar band is affected and moved to the nearby position of the Gc 2 band. Investigation of the proband's family shows that the variant occurs combined with the common alleles Gc 1F, Gc 1S and that it has an autosomal dominant inheritance. 相似文献
5.
A Seko K Kitajima M Iwasaki S Inoue Y Inoue 《The Journal of biological chemistry》1989,264(27):15922-15929
New glycoproteins of 100-120 kDa were isolated from the unfertilized eggs of flounder, Paralichthys olivaceus. Compositionally indistinguishable glycopeptides of 6 kDa were also purified from the activated or fertilized eggs. These high and low molecular mass glycoproteins are characterized by high (about 85%) carbohydrate content. Although some heterogeneities exist in the amino acid sequences, the 6-kDa glycopeptides (decapeptides with single large N-linked glycan chains), isolated from the fertilized eggs are the repeating units of the high molecular mass glycoproteins. As judged from several distinctive features the 100-120-kDa glycoproteins are apparently major components of cortical alveoli of flounder eggs and are regarded as members of glycoproteins we have defined under the name of "hyosophorin" (Kitajima, K., Inoue, S., and Inoue, Y. (1989) Dev. Biol. 132, 544-553). Composition analysis, Smith degradation, hydrazinolysis-nitrous acid deamination, permethylation analysis, and 400-MHz 1H NMR spectroscopy provided evidence for the structure of a novel penta-antennary glycan chain attached to the repeating unit (decapeptide) of the protein core. The structure thus determined is: (Formula: see text). The presence of a unique class of carbohydrate-rich glycoproteins (H-hyosophorin) in the unfertilized eggs, their conversion to the repeating unit (L-hyosophorin) at fertilization, and the finding of a free glycan chain that was formed by scission between the GlcNAc and Asn residues of L-hyosophorin, in the fertilized eggs including embryos of 4-11-h postinsemination, support the view that these molecules may be important in fertilization and subsequent development. 相似文献
6.
Filiform papillae, which were densely distributed all over the dorsal surface of the lingual body, were crown-shaped, with a central, circular area that sloped in the anterior direction and several branches that surrounded it in a semicircle from the back of the central area. Dome-shaped, fungiform papillae were scattered among these filiform papillae. At the posterior end of the lingual body, there were four circumvallate papillae. Prominent microridges and elevated intercellular borders were widely distributed in the central area of the filiform papillae and the interpapillar region. On the surface of the branches of the filiform papillae, microridges were rarely seen. On the surface of the fungiform papillae, indistinct microridges were observed. Histologically, the dorsal lingual epithelium revealed three different regions: the epithelium on the anterior side of the filiform papillae, the epithelium on the posterior side of the filiform papillae and the interpapillar epithelium. Whereas the basal and suprabasal cells are similar throughout, differences characterize the intermediate and surface layers. Keratohyalin granules appear predominantly in the intermediate layer in the epithelium on the anterior side of filiform papillae. In the epithelium on the posterior side of the filiform papillae, no keratohyalin granules occur and, instead, tonofibrils are prominent. The cells become significantly flattened. In the interpapillar epithelium, no keratohyalin granules are visible, and the tonofilaments occupy almost the entire cytoplasm of most cells in the intermediate and surface layers. The cells are larger in volume in these layers. 相似文献
7.
Heterogeneity of mouse lymphocytes with respect to interferon production upon influenza virus challenge in culture was studied. Spleen cells produced much more interferon than thymocytes or mesenteric lymph node cells. Spleen cells mainly responsible for interferon production belonged to the hydrocortisone-sensitive population. When spleen lymphocytes were separated into seven fractions by centrifugation on a serum albumin density gradient, they were found to differ greatly in interferon producing capacity; a small fraction of intermediate density, representing a few percent or less of the total lymphocytes, produced markedly high levels of interferon. 相似文献
8.
F Taguchi D Nagaki M Saito C Haruyama K Iwasaki 《Japanese journal of microbiology》1975,19(5):395-398
The prevalance and distribution of BK virus antibody in women during pregnancy and the occurrence of transplacental transmission of BK virus was determined by measurement of IgM antibody in the serum. Sera were collected from 63 nonpregnant women, 71 women who had experienced spontaneous abortion, 80 in the first trimester of pregnancy and the same 80 at delivery. Umbilical cord blood was also taken at delivery. Hemagglutination inhibition (HI) tests for BK virus used the micromethod of Gardner. Results indicate that a significant level of HI antibody was present in 70% of sera from all 4 experimental groups. This showed that BK virus infection was not limited to cases of spontaneous abortion. Of the 80 pregnant mothers, 6 showed a 4-fold or greater HI antibody seroconversion to BK virus after delivery. Of these 6 seroconversion patients, sensitive antibody was detected in 3 umbilical cords. Umbilical cords of those without seroconversion had no sensitive antibody. As evidenced by 2-NE-sensitive antibody, BK virus infections were also recognized in 6 of 71 women who aborted, 4 of 80 in the first trimester of pregnancy and 2 collected after delivery. The 2-ME-sensitive antibody was not found in any of 63 samples from nonpregnant women. Data indicate that 2-ME-sensitive antibody was present only in sera of women during pregnancy and after abortion. It may be possible that BK virus persists in a latent form in many healthy women and becomes activated during pregnancy. 相似文献
9.
Kikuchi T Iwasaki K Nishihara H Takamura Y Yagi O 《Bioscience, biotechnology, and biochemistry》2001,65(12):2673-2681
We developed a rapid and specific enumeration method for a trichloroethylene-degrading methanotroph, Methylocystis sp. strain M, based on a most probable number-polymerase chain reaction method for monitoring the bacterium at bioremediation sites. The primers designed for the mmoC gene of the soluble methane monooxygenase gene cluster were specific to strain M. Recovery of the cells with a membrane filter enabled us to detect strain M in trichloroethylene-contaminated groundwater. We used the enumeration method to monitor the number of strain M cells in effluent from soil columns supplied with trichloroethylene-contaminated groundwater. The number of strain M cells in the effluent depended on the amount of the strain M inoculated and the number of cells measured by the most probable number-polymerase chain reaction method was correlated with that measured by a culture method. The detection limit for strain M in effluent detected by MPN-PCR method was 4 to 8 x 10(2) cells/ml. 相似文献
10.
Two guaiane-type compounds, nardoguaianone J and K (1 and 2) and two aristolane-type compounds, kanshone F and G (3 and 4), were isolated from Nardostachys chinensis roots. The structures including the absolute configurations were elucidated by spectral means and by comparison of their CD spectra. 相似文献