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91.
S Hirohashi H Clausen E Nudelman H Inoue Y Shimosato S Hakomori 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(11):4163-4168
A fusion of human lymphocytes released from regional lymph nodes of papillary adenocarcinoma of lung cancer with mouse myeloma P3-X63-Ag8-U1 cells resulted in a stable hybridoma-secreting human IgM antibody (NCC-1004) that reacts with a large proportion of squamous cell carcinomas of lung and esophagus as well as carcinoma of thyroid glands. However, the antibody also reacts with normal red blood cells, B lymphocytes, and a few other limited loci in normal tissues such as the basal cells of bronchial epithelium and the basal cell layer of stratified squamous epithelium, as well as endothelium and alveolar lining epithelium. The antigen defined by NCC-1004 has been characterized as blood group i antigen on the basis of the following results. The antibody preferentially agglutinates cord erythrocytes in contrast to adult erythrocytes. The agglutination was obvious at 4 degrees C, but diminished greatly at 37 degrees C, and was enhanced after sialidase treatment. The antibody specifically reacts with lacto-norhexaosylceramide (nLc6) and sialosyllacto-norhexaosylceramide (IV3NeuAcnLc6), but does not react with lacto-neotetraosylceramide (nLc4), sialosyllacto-neotetraosylceramide (IV3NeuAcnLc4), lacto-isooctaosylceramide (IV6Gal beta 1----4GlcNAcnLc6; I antigen), and other standard glycolipids so far tested. The properties of the antibody and its antigen are identical to those previously described for the i blood group system. Inasmuch as the hybridoma was established by hybridization of lymphocytes derived from regional lymph nodes of lung cancer, and the antigen was found in the patient's lung cancer tissue, the i antigen in lung cancer is probably recognized as a tumor-associated antigen by the host's immune cell system. 相似文献
92.
Starvation-induced changes in rat brain corticotropin-releasing factor (CRF) and pituitary-adrenocortical response 总被引:1,自引:0,他引:1
Starvation-induced changes in CRF concentration in major brain regions and abnormalities in the pituitary-adrenal axis were examined in rats using rat CRF radioimmunoassay. The CRF concentrations in the hypothalamus and cerebellum were significantly reduced in the completely starved rats, while those in the midbrain, thalamus and neurointermediate lobe of the pituitary were significantly increased in the semi-starved or completely starved rats. No significant changes in the CRF concentrations were found in the pons, medulla oblongata and cerebral cortex. In the completely starved rats, the serum ACTH level was significantly reduced, whereas the serum corticosterone level was markedly elevated. These observations suggest that starvation may stimulate the CRF-ACTH-corticosterone system and that not only hypothalamic CRF but also extrahypothalamic CRF may be discretely related to feeding behavior or starvation. The reduced serum ACTH level in starved rats may be ascribed to the negative feedback effect of the elevated serum corticosterone. 相似文献
93.
Takeshi Murakami Hiroyuki Anzai Satoshi Imai Atsuyuki Satoh Kozo Nagaoka Charles J. Thompson 《Molecular & general genetics : MGG》1986,205(1):42-53
Summary We have isolated and studied the organization ofStreptomyces hygroscopicus genes responsible for the biosynthesis of the antibiotic herbicide bialaphos. Bialaphos production genes were cloned from
genomic DNA using a plasmid vector (pIJ702). Three plasmids were isolated which restored productivity toS. hygroscopicus mutants blocked at different steps of the biosynthetic pathway. Subcloning experiments using other nonproducing mutants showed
that four additional bialaphos production genes were also contained on these plasmids. A gene conferring resistance to bialaphos,
which was independently cloned using the plasmid vector pIJ61, and an antibiotic-sensitive host (S. lividans), was also linked to the production genes. Cosmids were isolated which defined the location of these genes in a 16 kb cluster. 相似文献
94.
Changes in lipoxygenase (LOX) activity were followed duringthe germination of rice seeds. The enzyme activity of 3-day-oldseedlings was 20 times higher than that of ungerminated seeds.Sixty per cent of the increased activity was found in shoots.The increase in LOX activity was mainly due to an increase inlipoxygenase-2 (LOX-2), a minor component in ungerminated seeds;this increase was inhibited by cycloheximide. LOX-2 was isolatedfrom the 3-day-old seedlings and compared for its enzymologicalproperties with rice lipoxygenase-3 (LOX-3), a major componentin ungerminated seeds. Both LOX-2 and LOX-3 were stable at pH5 to 8, but LOX-2 was more heatstable than LOX-3. Apparent Kmvalues of LOX-2 and LOX-3 for linoleic acid were 170 and 59µM, and those for linolenic acid were 5,300 and 88 µM,respectively. Both LOXs were inhibited by some metal ions andantioxidants. (Received February 5, 1986; Accepted May 9, 1986) 相似文献
95.
A species of Daphnia, Daphnia curvirostris Eylmann, found in high mountain lakes and ponds in central Japan is described. Although there were some differences in the shape of the male rostrum and the chromosome number between European populations as described by Johnson (1952) and Trentini (1980), and Japanese ones collected from high mountain waters, Japanese specimens had many characteristics similar to the taxon D. curvirostris of Europe. 相似文献
96.
Molecular cloning of the gene of a penicillin-binding protein supposed to cause high resistance to beta-lactam antibiotics in Staphylococcus aureus. 总被引:44,自引:10,他引:34
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M Matsuhashi M D Song F Ishino M Wachi M Doi M Inoue K Ubukata N Yamashita M Konno 《Journal of bacteriology》1986,167(3):975-980
A novel penicillin-binding protein, PBP-2' (Mr about 75,000), is known to be induced in excessively large amount by most beta-lactam compounds in cells of a clinically isolated strain of Staphylococcus aureus, TK784, that is highly resistant to beta-lactams and also most other antibiotics. This protein has very low affinities to most beta-lactam compounds and has been supposed to be the cause of the resistance of the cells to beta-lactams. A 14-kilobase DNA fragment was isolated from the cells that carried the gene encoding this penicillin-binding protein and also a genetically linked marker that is responsible for the resistance to tobramycin. This DNA was cloned on plasmid pACYC184 and was shown to cause both production of PBP-2' and resistance to tobramycin in Escherichia coli cells. However, the formation of PBP-2' in E. coli was only moderate and was independent of normal inducer beta-lactams. The PBP-2' formed in the E. coli cells showed slow kinetics of binding to beta-lactams similar to that of PBP-2' formed in the original S. aureus cells and gave a similar pattern of peptides to the latter when digested with the proteolytic V8 enzyme of S. aureus. 相似文献
97.
M Inaba H Morii Y Nishizawa T Miki M Yukioka S Morisawa A Inoue 《Journal of biochemistry》1986,100(3):591-595
Calcitonin (CT) stimulated phosphorylation of two liver cytosolic proteins whose molecular weights are 67,000 and 93,000. Stimulation of 67,000-Mr protein phosphorylation began shortly after subcutaneous injection of CT, reaching a maximum at 5 min and decreasing to below the control level at 30 min. The reaction was independent of cyclic AMP or Ca2+, and was not influenced by a calmodulin antagonist, W7. Stimulation of 93,000-Mr protein phosphorylation became evident by 30 min. This reaction was also stimulated by administration of vasopressin or epinephrine, which is known to cause increased phosphorylation of glycogen phosphorylase having the same molecular weight. The phosphorylation of 93,000-Mr protein, stimulated by CT, was dependent on Ca2+ but not on cyclic AMP, and appeared to be inhibited by W7. In addition, CT did not influence the phosphorylation of 61,000-Mr protein, a major protein phosphorylated in a cyclic AMP-dependent manner. These results suggest that CT may exert its effect on liver cells through protein phosphorylation, most probably in a cyclic AMP-independent manner. 相似文献
98.
Ieharu Hishinuma Tetsuro Ishii Hiroyuki Watanabe Shiro Bannai 《In vitro cellular & developmental biology. Plant》1986,22(3):127-134
Summary Mouse lymphoma L1210 cells maintained in vitro at a high cell density for a certain time period adapted themselves to the
in vitro environment and were able to grow indefinitely. From these adapted cells, more than 30 clones were isolated. They
all had much higher activity to take up cystine than the original L1210 cells, supporting a previous view that the deficiency
of the cystine uptake limits the survival and growth of L1210 cells in vitro. The cystine uptake of one cloned cell line was
characterized. The enhanced uptake of cystine in these cells was mainly mediated by a Na+-independent, saturable system and was potently inhibited by glutamate and some other anionic amino acids, but less by aspartate.
Such activity of cystine uptake was not observed in the original L1210 cells. The results suggest that, upon adaptation in
vitro, L1210 cells acquire a new cystine transport activity necessary for survival and growth in vitro. 相似文献
99.
The eggs ofAlcichthys alcicornis were spawned in tank at the laboratory and reared for the studies of embryonic, larval and juvenile development. This species takes place entosomatic fertilization, and females spawn fertilized eggs after copulation. The eggs are demersal and adhesive, released as a clump forming a thin layer on the bottom of tank. There was no significant difference in embryonic development between this species and other oviparous teleostean species. Hatching occurred between 17 and 18 days after spawning at a mean water temperature of 8.5?C. The newly hatched larvae averaged 4.44 mm in body length (BL). The larvae attained to post-larval stage at 5.80 mm BL, and juvenile stage at 10.2 mm BL. A specific feature of the post-larvae was the appearance of three lines of the melanophores on the caudal part of fin fold. Carotenoid first appeared on the nape at 8.70 mm BL, heavily emerged beyond 12.9 mm BL, and turned up on the back also beyond 15.2 mm BL. Scales on the lateral line were completed by 18.5 mm BL. Three pairs of flaps were observed on the dorsal surface of the head at 37.0 mm BL. External features of adult specimens are almost completed by 52.0 mm BL, yet the tip of the first preopercular was not branched but remained simple. 相似文献
100.