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1.
A method for enzyme immunoassay of thyroid-stimulating hormone (TSH) is described, TSH was conjugated with horseradish peroxidase according to periodate oxidation method. Separation of the bound and free was obtained by double-antibody solid-phase technique using Sepharose 4B-anti-rabbit immunogiobulin G (IgG)-geat IgG. The fluorescence reaction using tyramine and hydrogen peroxide as substrates was used for the determination of enzyme activity in order to increase the sensitivity of enzyme immunoassay. The standard curve for serum TSH was satisfactory to recognize TSH concentrations as 0.06 μU/tube. TSH values obtained by this method correlated well with those obtained by radioimmunoassay (r, 0.96). The coefficients of variation were 1.8 to 5.3% (within assay) and 5.1 to 10.5% (between assay). The method is about equal to radioimmunoassay with respect to sensitivity. Since it requires minimal equipment and is less expensive than radioimmunoassay, it is possible to perform routine assays even in laboratories with limited facilities. 相似文献
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A relatively large population of murine peritoneal exudate macrophages induced with viable BCG or heat-killed Corynebacterium parvum was stained by the antiserum prepared against purified gangliotetraosyl ceramide (asialo GM1), while only a small population of peritoneal resident macrophages or peritoneal exudate macrophages induced with proteose peptone was stained. The cytotoxicity assay of those macrophages with anti-asialo GM1 plus complement supported these results. Peritoneal macrophages induced with BCG or C. parvum showed strong cytotoxicity for EL4 cells in vitro, while resident or peptone-induced peritoneal macrophages showed no cytotoxicity. BCG- or C. parvum-induced peritoneal cells contained both NK cells and cytotoxic macrophages, and either in vivo or in vitro pretreatment of the cells with anti-asialo GM1 and complement abolished the activities of both types of cells. Peptone-induced peritoneal macrophages incubated with lymphokines (LK) or lipopolysaccharide (LPS) were cytotoxic for EL4 cells and contained an increased number of cells stained by anti-asialo GM1. The cytotoxicity of these in vitro activated macrophages was reduced by treatment with anti-asialo GM1 plus complement. When peptone-induced peritoneal macrophages were incubated with LK, the number of cells stained by anti-Ia antiserum increased, but the number did not increase when the macrophages were incubated with LPS. Pretreatment of peptone-induced macrophages with anti-asialo GM1 plus complement did not affect the ability of the macrophages to be activated by LK. These results taken together strongly suggest that the antigen (s) reactive with anti-asialo GM1 is expressed on the cell surface of cytotoxic peritoneal macrophages in mice. 相似文献
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The production of cloned fish in the medaka (Oryzias latipes) 总被引:5,自引:0,他引:5
The measurement of cellular DNA content by DNA microfluorometry revealed that medaka embryos that were fertilized with normal sperm and exposed to heat shock (41 degrees C for 3 min) or hydrostatic pressure (700 kg/cm2 for 10 min) at 85-95 min after insemination were tetraploid. Embryos fertilized with normal sperm and exposed to heat shock (41 degrees C for 2 min at 2-3 min after insemination) were triploid. These results suggest that heat shock or hydrostatic pressure at 85-95 min after insemination arrests the first cleavage, while heat shock at 2-3 min after insemination arrests the second meiotic division. Medaka clones have been produced by the following method: Eggs from orange-red or variegated variety were activated by UV-irradiated, genetically impotent sperm of wild-type fish (UV sperm). The haploid eggs obtained were diploidized by preventing the first cleavage with heat shock or hydrostatic pressure to produce homozygous females. Each of the two homozygous females was mated with vasectomized male in isotonic balanced salt solution to collect unfertilized eggs. The collected eggs were activated with UV sperm and converted from haploid to diploid by arrest of the second meiotic division with heat shock. Hatched fry of each homozygous diploid (all females) were fed with a methyltestosterone-containing diet (40 micrograms/gm diet) to produce sex-reversed males, which were mated with brood females, and thus two cloned lines were obtained. 相似文献
6.
Yuji Suehiro Teruhiro Okuyama Kiyoshi Naruse Takeo Kubo Hideaki Takeuchi 《FEBS letters》2010,584(16):3545-201
In this study, we demonstrated that human type-5 adenovirus infected the brain of the teleost fish, medaka (Oryzias latipes), in vivo. Injection of adenoviral vector into the mesencephalic ventricle of medaka larvae induced the expression of reporter genes in some parts of the telencephalon, the periventricular area of the mesencephalon and diencephalon, and the cerebellum. Additionally, the Cre-loxP system works in medaka brains using transgenic medaka carrying a vector containing DsRed2, flanked by loxP sites under control of the β-actin promoter and downstream promoterless enhanced green fluorescent protein (EGFP). We demonstrated that the presence of green fluorescence depended on injection of adenoviral vector expressing the Cre gene and confirmed that EGFP mRNA was transcribed in the virus-injected larvae. 相似文献
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Kazuo Imai Norihito Tarumoto Kiyoko Amo Makoto Takahashi Naoya Sakamoto Atsushi Kosaka Yasuyuki Kato Kei Mikita Jun Sakai Takashi Murakami Yutaka Suzuki Shigefumi Maesaki Takuya Maeda 《Parasitology international》2018,67(1):34-37
Cutaneous leishmaniasis (CL) is gaining attention as a public health problem. We present two cases of CL imported from Syria and Venezuela in Japan. We diagnosed them as CL non-invasively by the direct boil loop-mediated isothermal amplification method and an innovative sequencing method using the MinION? sequencer. This report demonstrates that our procedure could be useful for the diagnosis of CL in both clinical and epidemiological settings. 相似文献
8.
Kiyoko Yokota Robert W. Sterner 《Proceedings. Biological sciences / The Royal Society》2011,278(1704):458-463
Multicellular organisms that benefit from division of labour are presumably descended from colonial species that initially derived benefits from larger colony size, before the evolution of specialization. Life in a colony can have costs as well as benefits, but these can be hard to measure. We measured physiological costs to life in a colony using a novel method based on population dynamics, comparing growth rates of unicells and kairomone-induced colonies of a green alga Desmodesmus subspicatus against a reference co-occurring species. Coloniality negatively affected growth during the initial log growth phase, while no adverse effect was detected under nutrient-limited competitive conditions. The results point to costs associated with traits involved in rapid growth rather than those associated with efficient growth under resource scarcity. Some benefits of coloniality (e.g. defence from herbivory) may be different from when this trait evolved, but our approach shows how costs would have depended on conditions. 相似文献
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An alpha-helical coiled-coil structure is one of the basic structural units in proteins. Hydrophilic residues at the hydrophobic positions in the coiled-coil structure play important roles in structures and functions of natural proteins. We reported here a peptide that formed a triple stranded alpha-helical coiled-coil showing the pH-dependent structural change. The peptide was designed to have two His residues at the hydrophobic positions of the center of the coiled-coil structure. The peptide folded into a triple stranded coiled-coil at neutral pH, while it unfolded at acidic pH. This construct is useful to create a protein that the structure or function is controlled by pH. 相似文献
10.
Koshi Nakamura Masaru Sakurai Katsuyuki Miura Yuko Morikawa Shin-ya Nagasawa Masao Ishizaki Teruhiko Kido Yuchi Naruse Yasushi Suwazono Hideaki Nakagawa 《PloS one》2013,8(1)
Given the lack of economic studies evaluating the outcomes of smoking cessation programs from the viewpoint of program sponsors, we conducted a case study to provide relevant information for worksites. The present study was carried out between 2006 and 2008 at a manufacturing factory in the Toyama Prefecture of Japan and included subjects who voluntarily entered a smoking cessation program. The program included face-to-face counselling followed by weekly contact to provide encouragement over six months using e-mail or inter-office mail. Nicotine patches were available if required. All 151 participants stopped smoking immediately. Over the 24-month study period, self-report showed 49.7% abstained continuously from smoking. The rate of 24-month consecutive abstinence was higher in participants with lower Fagerström Test scores for Nicotine Dependence at baseline than in those with higher scores (63.6% for 0–2 points vs. 46.5% for 3–6 points vs. 43.8% for 7–10 points; chi-square test p = 0.19). A logistic regression model showed a significant linear trend for the association between the score and abstinence status after adjustment for possible confounding factors (p = 0.03). The crude incremental cost for one individual to successfully quit smoking due to the support program was ¥46,379 (i.e., ¥100 = $1.28, £0.83, or €1.03 at foreign exchange rates). The corresponding costs for the three categories of the Fagerström Test score for Nicotine Dependence were ¥31,953, ¥47,450 and ¥64,956, respectively. When a sensitivity analysis was conducted based on the 95% confidence interval of the success rate, the variance in the corresponding costs was ¥25,514–45,034 for 0–2 points, ¥38,344–61,824 for 3–6 points, and ¥45,698–108,260 for 7–10 points. The degree of nicotine dependence may therefore be an important determinant of the cost-effectiveness of smoking cessation programs. 相似文献