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61.
Yuzuru Mikami Sen Feng Yu Katsukiyo Yazawa Kazutaka Fukushima Akio Maeda Jun Uno Kiyoshi Terao Naoki Saito Akinori Kubo Ken -ichiro Suzuki 《Mycopathologia》1990,112(2):113-118
During our studies on toxic substances from clinically isolated Nocarida, a new isolate identified as Nocardia otitidiscaviarum from cutaneous nocardiosis was found to produce a toxic substance called HS-6 that had strong in vitro as well as in vivo toxicity. The mouse intraperitoneal LD50 value was 1.25 mg/kg and the ED50 value for L1210 cultured cells was 0.3 ng/ml. The structure of HS-6 was determined and found to belong to the 16-membered macrocyclic group with a molecular formula of C43H68O12. HS-6 also showed activity against pathogenic fungi such as Cryptococcus neoformans. 相似文献
62.
Monoclonal antibodies to human germ cell tumors from "routine" paraffin-embedded pathological specimens 总被引:1,自引:0,他引:1
We have established a method for monoclonal antibody (MoAb) preparation from routine paraffin-embedded tissue of human seminoma as an immunogen. Three 40-microns thick sections were deparaffinized and rehydrated. An eight-week-old BALB/c mouse was immunized intraperitoneally with this extract, which showed no detectable protein bands on sodium laurylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Five monoclonal antibodies (MoAbs) with different characteristics were obtained; one reacted with the nucleus, two with the cytoplasm, and two with the cytoplasmic membrane. One of the MoAbs 5G9 reacted with spermatogonia in normal human tissues and with seminoma, embryonal carcinoma and choriocarcinoma in the testicular tumors. 相似文献
63.
Hiroto Kobayashi Masako Kawasaki Hiroshi Ishizaki Ryoichi Fukushiro Ryoichi Matsumoto 《Mycopathologia》1990,112(1):19-22
A survey for the natural occurrence of Fusarium mycotoxins, deoxynivalenol (DON), nivalenol (NIV) and zearalenone (ZEN), in Dutch cereals (totaling 29 samples) harvested in 1984/1985, showed that 90%, 79% and 62% of samples were contaminated with DON, NIV and ZEN, respectively. Average contents (ng/g) in the total of positive samples were 221 (DON), 123 (NIV) and 61 (ZEN). Among the cereals examined, the highest concentrations (ng/g) was 3198 (DON), 1875 (NIV) and 677 (ZEN) in a yellow corn sample for animal feed. The results of this survey show that Dutch cereals were relatively significantly contaminated with Fusarium mycotoxins. 相似文献
64.
Kiyoshi Takahashi Tadashi Yoshino Tadaatsu Akagi Katsuya Miyatani Kazuhiko Hayashi Hiroshi Sonobe Yuji Ohtsuki 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,59(1):159-164
In order to clarify the function of human S100β- positive T-cells, S100β-positive T-leukemia cells (S100β TLC) were examined in vitro. S100β TLC were obtained from the peripheral blood of a patient with S100β-positive T-cell leukemia and enriched by an E-rosetting method. Two dimensional flow cytometric analysis indicated that the
vast majority of the E-positive fraction were S100β TLC expressing CD3 and CD8 antigens. Although S100β TLC expressed CD3 antigen, they were negative for the α/β and γ/δ T-cell antigen receptor (TCR) defined by monoclonal antibodies
(mabs) WT-31 and δ TCS-1, respectively. It was speculated that S100β TLC initially expressed α/β TCR but lost it during malignant transformation. When S100β TLC were cultured for 24 h, they acquired cytotoxic activity towards various NK-sensitive cell lines including K-562, Molt-3
and CEM-CCLF, but did not exhibit lysing activity towards NK-resistant cell lines including Raji, Daudi and MT-1. Despite
the NK-activity of cultured S100β TLC, they lacked the morphological features of large granular lymphocytes (LGL). S100β TLC did not exhibit lymphokine-activated killer (LAK) activity. When S100β TLC were cocultivated with NK-sensitive cells or NK-resistant cells, they selectively bound to NK-sensitive cells, indicating
that they lysed target cells by cell-to-cell contact. The finding that S100 β TLC lacked TCR molecules and their NK activity
was not inhibited by mabs reactive with the CD3-TCR complex indicated that the CD3-TCR complex was not involved in their target
recognition. These findings suggest that S100 β-positive T-cells are functionally similar to NK cells. We discuss the roles
of S100 β-positive T-cells in the human immune system. 相似文献
65.
Hiroshi Yao Hiroaki Ooboshi Seizo Sadoshima Kentaro Takano Setsuro Ibayashi Masatoshi Fujishima 《Neurochemical research》1990,15(5):547-549
To determine the level of cerebral blood flow reduction which causes striatal dopamine release, extracellular dopamine and cerebral blood flow was simultaneously determined using in vivo brain dialysis and a hydrogen clearance method, respectively, in the striatum of spontaneously hypertensive rats, before and during experimental cerebral ischemia. The ischemic flow threshold for neurotransmitter dopamine release was found to be 20% of the resting value or 8–10 ml/100g/min of cerebral blood flow, being similar to those for energy and membrane failures. 相似文献
66.
Tatsuo Nakahara Makoto Hirano Takashi Matsumoto Toshihide Kuroki Yoshinori Tatebayashi Tetsuyuki Tsutsumi Kouji Nishiyama Hiroaki Ooboshi Kaoru Nakamura Hiroshi Yao Akio Shiraishi Michinori Waki Hideyuki Uchimura 《Neurochemical research》1990,15(6):609-611
DNA and RNA contents in 20 brain regions or nuclei of the rat were determined by a highly sensitive method using high-performance liquid chromatography with electrochemical detection. The high DNA and RNA contents were found in the hypothalamic nuclei, especially the median eminence-arcuate nucleus. These results may be available for the preparation of nucleic acids as the regional control. 相似文献
67.
Hiroshi Yonemitsu Koichiro Shimomura Motoyoshi Satake Shunji Mochida Masahiko Tanaka Thoru Endo Akira Kaji 《Plant cell reports》1990,9(6):307-310
Hairy roots were obtained following inoculation of the stems of Lobelia inflata L. with Agrobacterium rhizogenes strain ATCC 15834. These hairy roots contained agropine and mannopine. In addition, lobeline was detected by HPLC and confirmed by mass spectrometry. Various media were tested for the growth of hairy roots as well as for the content of lobeline in hairy roots. The growth rate of hairy roots cultured in Nitsch and Nitsch's medium was approximately one third of those cultured in other media. The lobeline content of hairy roots (18–54 g/g dry weight) cultured in these media was the same order of magnitude compared with that of roots of L. inflata (24 g/g dry weight) cultivated in pots. The hairy roots cultured in Nitsch and Nitsch's medium were morphologically different from those cultured in other media.Abbreviations MS medium
Murashige and Skoog's medium
- 1/2 MS medium
one-half strength of the standard Murashige and Skoog's medium
- B5 medium
Gamborg's B5 medium
- NN medium
Nitsch and Nitsch's medium
- FW
fresh weight
- DW
dry weight 相似文献
68.
Protoplasts isolated enzymatically from juvenile leaflets of sporophytes in fern Lyqodium japonicum were inoculated in a MS medium containing NAA 2.7 m, BAP 2.2 m, 0.6 M mannitol, and 0.05 M sucrose. Cell division took place within 8 days of culture initiation, and after 30 days cell-clusters with 10–15 cells were observed. When the cell-clusters were transferred into fresh hormone-free medium containing no mannitol, they developed rhizoids and protonema-like regenerants. About 2 months later, cordate prothallia developed bearing both antheridia and archegonia.Abbreviations MS
Murashige and Skoog (1962)
- NAA
naphthalene acetic acid
- BAP
6-benzylaminopurine 相似文献
69.
A physical map of the human salivary proline-rich protein gene cluster covers over 700 kbp of DNA 总被引:5,自引:0,他引:5
By using a linking library, we have experimentally linked, ordered, and spaced four of the six loci that constitute the human salivary proline-rich protein (PRP) multigene family. The methods used for mapping these four PRP genes may be useful in other multigene systems in which no probes unique to each member of genes are available, but in which some enzyme site that occurs only once in each member of the family can be found. The remaining two PRP loci have been provisionally mapped and linked within the gene cluster primarily on the basis of the resulting order giving a simple map. The order of the six loci that most simply accounts for our data is PRB2, PRB1, PRB4, PRH2, PRB3, and PRH1. The PRP gene cluster spans at least 700 kbp on chromosome 12 at p13.2. A scheme for the evolution of the cluster that requires an initial gene duplication followed by three unequal but homologous crossovers is given. 相似文献
70.
Shigeru Kumano Masashi Ihira Yasuo Maeda Misako Yamauchi Eiji Matsumoto Isao Matsuda 《Ecological Research》1990,5(2):221-235
Diatom assemblages of sediments obtained from three sites on Kushiro Moor were analyzed to investigate the Holocene sedimentary
history. The results showed that: 1) The Takkobu site was originally at the bottom of the paleo-Kushiro Bay, and after-wards
the paleo-Takkobu Lagoon developed, became sealed off, and changed to a freshwater lake. The succession to peat moor probably
began about 2000 yr B.P. at the Takkobu site. 2) The Tsurui site was originally at the bottom of the paleo-Kushiro Bay, then
changed to the paleo-Kushiro Lagoon and became peat moor as a result of the first Holocene regression, which finished about
3600 yr B.P. The site then returned to a brackish lake again, probably due to the second Holocene transgression between 3600
and 3000 yr B.P., thereafter passing through brackish lake and freshwater lake stages, and eventually becaming peat moor at
about 2000 yr B.P., 3) At the Chuo site, the second paleo-Kushiro Bay developed again as a result of the second Holocene transgression,
which finished about 3000 yr B.P. Thereafter, brackish or freshwater lakes, rivers, and then peat moor developed in the central
area of Kushiro Moor. 4) The second marine diatom zone (MD2 Zone), which indicates the second Holocene transgression, complete by about 3000 yr B.P., is detected only at the Chuo site
in the central area of Kushiro Moor. 相似文献