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991.
Host-cell reactivation, that is, the degree of survival of Herpes simplex virus after UV irradiation, was high in African green monkey BSC-1 cells, intermediate in normal human fibroblasts and human FL cells, and low in both xeroderma pigmentosum (XP) cells and mouse L cells. However, colony-forming ability after UV was high for FL, normal human fibroblasts and L cells, slightly low for BSC-1 cells and extremely low for XP cells. During the 24-h post-UV incubation period, up to about 50% of the thymine-containing dimers in the acid-insoluble DNA fraction disappeared at an almost equal rate for BSC-1, FL and normal human cells but remained unaltered for the XP cells. Alkaline sucrose gradient centrifugation of DNA after UV irradiation revealed only a slight difference between FL and BSC-1 cells in the kinetics of formation of single-strand breaks and their apparent repair. From these and the previously known characters of L cells possessing reduced excision-repair ability, if any, we may conclude that, if the survival of UV-irradiated Herpes simplex virus on a test line of human or other mammalian cells is as low as that on excisionless XP cells, then it is very probable that the test cell line is defective in excision repair. This reasoning leads to the presumptive conclusion that mouse L cells have an enhanced post-replication repair other than excision repair to deal with UV damage responsible for inactivation of colony-forming ability. 相似文献
992.
Shiro Ohki Katsuhiro Imaki Fumio Hirata Toshio Hanyu Nobuhiko Nakazawa 《Prostaglandins & other lipid mediators》1974,6(2):137-148
Radioimmunoassays for measuring prostaglandin F2α (PGF2α) and 5α, 7α-dihydroxy-11-keto tetranorprosta-1,16-dioic acid, PGF2α-main urinary metabolite (PGF2α-MUM), with 125I-tyrosine methylester amide (TMA) of PGF2α and PGF2α-MUM were developed.Antibody to PGF2α was produced in rabbits immunized with conjugates of PGF2α coupled to bovine serum albumine. Antibody to PGF2α-MUM was also produced in rabbits immunized with conjugates of PGF2α-MUM coupled to bovine serum albumin.PGF2α-125I-TMA had an affinity to antiserum to PGF2α. PGF2α-MUM-125I-TMA also responded to antiserum to PGF2α-MUM. 相似文献
993.
Shiro Ohki Katsuhiro Imaki Fumio Hirata Toshio Hanyu Nobuhiko Nakazawa 《Prostaglandins & other lipid mediators》1974,6(2)
Radioimmunoassays for measuring prostaglandin F2α (PGF2α) and 5α, 7α-dihydroxy-11-keto tetranorprosta-1,16-dioic acid, PGF2α-main urinary metabolite (PGF2α-MUM), with 125I-tyrosine methylester amide (TMA) of PGF2α and PGF2α-MUM were developed.Antibody to PGF2α was produced in rabbits immunized with conjugates of PGF2α coupled to bovine serum albumine. Antibody to PGF2α-MUM was also produced in rabbits immunized with conjugates of PGF2α-MUM coupled to bovine serum albumin.PGF2α-125I-TMA had an affinity to antiserum to PGF2α. PGF2α-MUM-125I-TMA also responded to antiserum to PGF2α-MUM. 相似文献
994.
Shiro Mori 《Cell and tissue research》1966,70(4):461-488
Summary The rat corpus striatum was perfused vitally with glutaraldehyde, immersed in OsO4 and then observed under an electron microscope.Numerous small cells in the neostriatum show a simple cytoplasmic structure, while the large cells possess a complicated fine structure. These are differentiated under the elctron microscope into two kinds, which seem to have functional differences. The large pallidal cells containing much pale cytoplasm are covered with many varied axonal boutons from the cell body to the dendritic terminal making numerous axo-somatic or axo-dendritic trunk synapses. Numerous axo-dendritic, or spine synapses are recognized in the neostriatal neuropil.These numerous axon terminals, which belong to striatal nerve cells or other nuclei of the brain, are classified morphologically into several types. At least five types of synaptic vesicles are distinguished by their size or by the presence of fine dense granules on their membranes, and seem to be specific to the neostriatum.Many myelin interruptions and several kinds of glial cells in the corpus striatum are observed. Moreover, the ventricular wall of the caudate nucleus, namely, the ependyma, and two kinds of subependymal cells are described and discussed with reference to the subependymal layer. 相似文献
995.
996.
Yukio Hitotsuyanagi Yoshiaki Anazawa Takehiro Yamagishi Kazunori Samata Tomoko Ichihara Kayoko Nanaumi Noriko Okado Shiro Nakaike Mariko Mizumura Koichi Takeya Hideji Itokawa 《Bioorganic & medicinal chemistry letters》1997,7(24):263-3128
Deoxybouvardin (3) was reacted with 2-dialkylaminoethyl chloride salts to produce analogues 4a-h. All analogues retained antitumor activity against P388 leukemia in mice, and analogue 4c showed more promising antitumor activity than RA-VII (1) against the P388 leukemia, B16 melanoma and colon adenocarcinoma 26 murine tumor models. The hydrochloride salt of 4c is soluble in water. 相似文献
997.
Abstract. We examined the factors that control seedling establishment on barren substrates on the pyroclastic flows from Mount St. Helens. From June to September in 1993, we monitored seedling and microhabitat changes in 240 20 cm × 20 cm quadrats on the Pumice Plain. Seedlings emerged in 104 quadrats (43.3 %). The most abundant species were Anaphalis margaritacea, Hypochaeris radicata, Lupinus lepidus and Epilobium angustifolium. Measured site characteristics included topography, particle size distribution, ground surface movements, soil water content, organic matter, pH, and presence or absence of dead lupines. Quadrats with seedlings had higher cover of dead lupines, higher amount of rock and gravel substrate, and a greater cover of rills. More seedlings emerged where eroded material accumulated. Compared to coarse-textured surfaces, silt surfaces had higher organic matter, held more water, and showed higher pH. However, seedlings became established more frequently on coarse-textured surfaces. In greenhouse experiments, a higher percentage of Hypochaeris seeds germinated on silt than on sand or gravel. The germination of Anaphalis and Epilobium did not differ with soil texture, but was higher at higher moisture levels. Seedling colonization is more dependent on ground surface microtopography, particle size, and ground movement than on the chemical status of these volcanic deposits. 相似文献
998.
A rapid PCR-aided selection of a rice line containing the Rf-1 gene which is involved in restoration of the cytoplasmic male sterility 总被引:10,自引:0,他引:10
Ichikawa Norio Kishimoto Noaki Inagaki Akiko Nakamura Atsushi Koshino Yoko Yokozeki Yumi Oka Masaaki Samoto Shiro Akagi Hiromori Higo Kenichi Shinjyo Choyu Fujimura Tatsuhito Shimada Hiroaki 《Molecular breeding : new strategies in plant improvement》1997,3(3):195-202
Cytoplasmic male sterility (CMS) is widely known in higher plants, the mechanism of which is believed to involve incompatibility between nuclei and cytoplasms. In rice lines with the CMS trait, fertility is restored by the aid of a nuclear-encoded gene, Rf-1, whose locus has been determined in chromosome 10. We found a particular PCR-amplified fragment, designated fL601, that specifically amplified using the DNAs from Rf-1 lines tested as templates. RFLP mapping of the fL601 locus revealed that there are two loci for the fL601, and that both are tightly linked to the Rf-1 locus. Progeny analysis also showed high frequency of their co-segregation. Southern analysis of the genomic DNA demonstrated that the Rf-1 lines shared a unique sequence in the fL601 region. These results enabled us to construct a system for specific detection of the corresponding regions. Utilizing this detection system, we established a simple PCR-mediated selection method for the Rf-1 lines, which may facilitate the breeding for hybrid rice. 相似文献
999.
Jorge Padilla Masao Yamada Yasushi Takahashi Takashi Tsukazaki Jun Nakamura Mariko Yoshida Fumio Uno Yujiro Arao Shiro Nii 《Microbiology and immunology》1997,41(3):203-207
To analyze the mechanisms for in vitro emergence of the syncytial variants of herpes simplex virus type 1 (HSV-1), several cell lines were infected with a mixture of equal amounts of two HSV-1 variants, one syncytial and the other non-syncytial, and changes in their relative abundance were monitored during passage. With a combination of two variants of the Miyama strain of HSV-1, the syncytial variant became dominant during passage in Vero, RK-13 and FL cells. On the other hand, the ratios of the two variants remained around 1:1 during the passage in HEp-2, MGC and HEL cells. In another set of variants of the SKO strain of HSV-1, the outcomes were different from those of the Miyama strain in the FL, MGC and HEp-2 cells. The ratios of the two variants remained around 1:1 during passage in FL cells, while the non-syncytial variant became dominant during passage in MGC and HEp-2 cells. In addition, we examined the effects of a complement and interferon-β (IFN-β) on the outcome of the selection. As a result, the complement slowed the selection of a syncytial variant, whereas IFN-β facilitated it. 相似文献
1000.