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41.
Structure of genomic DNA for rat platelet phospholipase A2 总被引:2,自引:0,他引:2
A genomic DNA for rat platelet phospholipase A2 was isolated by screening a rat genomic library with oligonucleotide probes based on its published amino acid sequence. The rat platelet phospholipase A2 gene had a total length of about 2.5 kb and contained five exons and four introns. The intron-exon structure of the rate gene was similar to that of human non-pancreatic phospholipase A2. 相似文献
42.
Akira Niwa Katsuhiko Yamamoto Kenji Sorimachi Yosihiro Yasumura 《In vitro cellular & developmental biology. Plant》1980,16(11):987-993
Summary The rat hepatoma cell line, H4-II-E, was grown serially over a I-year period and about 30 passages in arginine-, glutamine-,
and tyrosine-deprived and ornithine-supplemented Eagle's mininum essential medium with no supplements other than biotin. The
adapted cel line, R-Y121B, proliferates in the above mentioned medium with a doubling time of about 4 days and maintains hepatic
“marker” enzymes such as tyrosine aminotransferase, phenylalanine hydroxylase, and all the enzymes of the urea cycle.
This work was supported in part by Grant-in-Aid for Cancer Research 301050 and Science Research Grant 337013 from the Ministry
of Education, Science and Culture, Japan. 相似文献
43.
Kenji Maeda Shunsuke Kawaguchi Toshimitsu Niwa Toyokazu Ohki Kaizo Kobayashi 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,221(2):199-204
A gas chromatographic—mass spectrometric analysis was used to separate and identify abnormal compounds in the nail of psoriatic patients. The nail was extracted with heated ethanol, and the extract was analyzed with and without trimethylsilylation. Tetradecanoic acid octadecyl ester, hexadecanoic acid octadecyl ester and octadecanoic acid octadecyl ester were first identified in the psoriatic nail, but were not detected in normal nail. 相似文献
44.
Synthesis by DNA polymerase I on bleomycin-treated deoxyribonucleic acid: a requirement for exonuclease III 总被引:7,自引:0,他引:7
phi X174 RFI DNA treated with bleomycin (BLM) under conditions permitting nicking does not serve as a template-primer for Escherichia coli DNA polymerase I. Purified exonuclease III from E. coli and extracts from wild-type E. coli strains are able to convert the BLM-treated DNA to suitable template-primer, but extracts from exonuclease III deficient strains are not. Brief digestion by exonuclease III is enough to create the template-primer, suggesting that the exonuclease III is converting the BLM-treated DNA by a modification of 3' termini. The exonucleolytic rather than the phosphatase activity of exonuclease III appears to be involved in the conversion. Comparative studies with micrococcal nuclease indicate that BLM-created nicks do not have a simple 3'-P structure. Bacterial alkaline phosphatase does not convert BLM-treated DNA to template-primer. The endonuclease VI activity associated with exonuclease III does not incise DNA treated with BLM under conditions not allowing nicking, in contrast to DNA with apurinic sites made by acid treatment, arguing that conversion does not require the endonuclease VI action on uncleaved sites. 相似文献
45.
Curing of the killer deoxyribonucleic acid plasmids of Kluyveromyces lactis. 总被引:22,自引:3,他引:19
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Ultraviolet irradiation gave rise to frequent curing of killer plasmids pGKl1 and pGK12 of Kluyveromyces lactis. Almost all of the nonkillers obtained lost both plasmids, but one of them lost only pGKl1. The disappearance of pGKl1 was accompanied by the simultaneous loss of the killer activity and of the resistance to the killer factor. A new plasmid, pGKl1S, was obtained, which arose from a deletion in the central region of pGKl1. Genetic analysis suggested that pGKl1S has the killer gene lost by the deletion and the resistance gene intact and that pGKl1S shares the same replication control with pGKl1. 相似文献
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Oocytes recovered at various times from immature rats treated with PMSG and HCG were incubated with capacitated epididymal spermatozoa of mature rats. In the presence of follicular cells, sperm penetration was not observed 4 hr after incubation in the oocytes at stages from the intact germinal vesicle to the chromatin mass, but 7 to 55% of oocytes were penetrated at stages from the condensed germainal vesicle to metaphase II. After the removal of follicular cells, 15 to 72% of the oocytes at any stage were penetrated. After further incubation for 15 hr, the proportion of penetrated oocytes increased from 8 to 98% from early to late stages and that of penetrated oocytes with a male and female pronucleus increased from 9 to 100% as maturation progressed. Although the average number of spermatozoa/oocyte was not correlated with its maturation, transformation of the sperm head into a male pronucleus was retarded or failed, especially in the younger oocytes. Following incubation in a defined medium for 13 hr, 85% of oocytes at the intact germinal vesicle stage matured to the stage of the first polar body formation, but only 18 to 22% of these mature oocytes were penetrated by spermatozoa and only a few of the penetrated oocytes cleaved into normal two-cell eggs. When eggs recovered from oviducts 14 to 20 hr after ovulation were exposed to capacitated spermatozoa, the proportion of penetrated eggs (86 to 98%) and that of polyspermic eggs (11 to 27%) were not related to the ages of the eggs, but failure of transformation of the sperm head and the proportion of abnormal eggs increased 14 to 20 hr after ovulation. 相似文献
49.
50.
Takashi Nishinaka Yui Yamazaki Atsuko Niwa Hidenori Wake Shuji Mori Tadashi Yoshino 《Biomarkers》2020,25(3):305-313
AbstractBackground: Cerebral small vessel disease (CSVD) is associated with future stroke. Although pathological alteration in small vessels of patients with CSVD can be detected by neuroimaging, diagnosis of CSVD is delayed because it is an asymptomatic disease. The stroke-prone spontaneously hypertensive rat (SHRSP) show similar pathological features to human CSVD and develop stroke-related symptoms with advancing age.Objective: We investigated the time course of haematological parameters in Wistar rats and SHRSP.Material and Methods: Blood cells were analysed using an automated haematological analyser.Results: SHRSP develop stroke-related symptoms including onset of neurological symptoms, decreased body weight and blood brain barrier leakage between 12 and 14?weeks of age. Lymphocyte counts were gradually decreased at 3?weeks before development of stoke-related symptoms and then were further decreased after the development of stroke-related symptoms. The both mean platelet volume and large platelet ratio gradually increased at 3?weeks before the development of stoke-related symptoms. However, although SHRSP showed more microcytic red cells than Wistar rats, the trajectories of change in erythrocyte-related parameters were similar between Wistar rats and SHRSP.Conclusion: Our pilot study suggests that alterations of lymphocyte count and platelet volume predictive indicators for asymptomatic CSVD and symptomatic stroke in SHRSP. 相似文献