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排序方式: 共有711条查询结果,搜索用时 31 毫秒
601.
Evi9, a common site of retroviral integration in BXH2 murine myeloid leukemias, encodes a C2H2 zinc finger protein and is overexpressed in these leukemic cells. To investigate a possible role of EVI9 in the human hematopoietic system, we isolated the cDNA clone of the human homologue. Human EVI9, located on the chromosome 2p13 region, contains an open reading frame of 797 amino acids that is 98.7% identical to the mouse protein. RT-PCR analysis of purified human hematopoietic cells showed that EVI9 is expressed in CD34-positive myeloid precursors, B cells, monocytes, and megakaryocytes, but only weakly in T lymphocytes, suggesting that EVI9 may play an important role in hematopoiesis. Furthermore, EVI9 was down-regulated during myeloid differentiation of HL60 cells induced by all-trans-retinoic acid, whereas the expression remained during monocytic differentiation induced by phorbol 12-myristate 13-acetate. These results indicate a distinct role for EVI9 in human hematopoietic cells and suggest that EVI9 may cause leukemia through inhibition of myeloid differentiation. 相似文献
602.
Michio Tsuda Yukari Sei Masahiko Matsumoto Hiroshi Kamiguchi Masahiro Yamamoto Yukito Shinohara Tsuyoshi Igarashi Masaichi Yamamura 《Human genetics》1992,90(4):467-468
A new mutant -1-antichymotrypsin (variant ACT) was found by polymerase chain reaction single strand conformation polymorphism and direct sequencing. In this variant ACT, two bases (AA) were deleted from codon 391. This resulted in a different amino acid sequence downstream of the deletion point, elongating the peptide chain by 10 amino acids. 相似文献
603.
A Spore Coat Protein, CotS, of Bacillus subtilis Is Synthesized under the Regulation of ςK and GerE during Development and Is Located in the Inner Coat Layer of Spores 下载免费PDF全文
604.
S Ohnishi M Murata S Oikawa Y Totsuka T Takamura K Wakabayashi S Kawanishi 《Mutation research》2001,494(1-2):63-72
Norharman (9H-pyrido[3,4-b]indole), which is a heterocyclic amine included in cigarette smoke or cooked foodstuffs, is not mutagenic itself. However, norharman reacts with non-mutagenic aniline to form mutagenic aminophenylnorharman (APNH), of which DNA adducts formation and hepatocarcinogenic potential are pointed out. We investigated whether N-OH-APNH, an N-hydroxy metabolite of APNH, can cause oxidative DNA damage or not, using 32P-labeled DNA fragments. N-OH-APNH caused Cu(II)-mediated DNA damage. When an endogenous reductant, beta-nicotinamide adenine dinucleotide (NADH) was added, the DNA damage was greatly enhanced. Catalase and a Cu(I)-specific chelator inhibited DNA damage, suggesting the involvement of H(2)O(2) and Cu(I). Typical -*OH scavenger did not inhibit DNA damage. These results suggest that the main reactive species are probably copper-hydroperoxo complexes with DNA. We also measured 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) formation by N-OH-APNH in the presence of Cu(II), using an electrochemical detector coupled to a high-pressure liquid chromatograph. Addition of NADH greatly enhanced 8-oxodG formation. UV-VIS spectra and mass spectra suggested that N-OH-APNH was autoxidized to nitrosophenylnorharman (NO-PNH). We speculated that NO-PNH was reduced by NADH. Cu(II) facilitated the redox cycle. In the presence of NADH and Cu(II), very low concentrations of N-OH-APNH could induce DNA damage via redox reactions. We conclude that oxidative DNA damage, in addition to DNA adduct formation, may play an important role in the expression of genotoxicity of APNH. 相似文献
605.
Endurance exercise causes interaction among stress hormones, cytokines, neutrophil dynamics, and muscle damage. 总被引:12,自引:0,他引:12
K Suzuki M Totsuka S Nakaji M Yamada S Kudoh Q Liu K Sugawara K Yamaya K Sato 《Journal of applied physiology》1999,87(4):1360-1367
We analyzed adaptation mechanisms regulating systemic inflammatory response of the stressed body by using an experimental challenge of repeated exercise bouts and accompanying muscle inflammation. Eight untrained men bicycled at 90 W for 90 min, 3 days in a row. Exercise induced peripheral neutrophilia with a leftward shift of neutrophil nucleus and neutrophil priming for oxidative activity determined by luminol-dependent chemiluminescence. Plasma growth hormone and interleukin-6 rose significantly after exercise and were closely correlated with the neutrophil responses. Serum creatine kinase and myoglobin levels as muscle damage markers rose after exercise in "delayed onset" and were closely correlated with the preceding neutrophil responses. These exercise-induced responses were strongest on day 1, but the magnitude gradually decreased with progressive daily exercise. In contrast, the magnitude of catecholamine responses to exercise sessions gradually rose, possibly suppressing neutrophil oxidative responses. These results indicate that stress-induced systemic release of bioactive substances may determine neutrophil mobilization and functional status, which then may affect local tissue damage of susceptible organs. 相似文献
606.
Sho Yoshida Shunichi Murano Yasushi Saito Hidekuni Inadera Jim Tashiro Junji Kobayashi Naoko Tadokoro Tetsuto Kanzaki Masaki Shinomiya Nobuhiro Morisaki Kuniko Ohono Yo Ishikawa Kohji Shirai Yukari Azuma Kazuhiro Kodama 《Obesity (Silver Spring, Md.)》1995,3(Z2):205s-209s
It is apparent that personality is related to the pathogenesis of obesity, and that understanding the personality of the patient may be a key to successful treatment of the disease. Using the Rorschach test and interviews by a psychiatrist, the types of personality were classified into four groups according to the healthiness of personalities. The judgment of healthiness was based mainly on the scores obtained from the Rorschach test This classification revealed that the occurrence of mental and physical symptoms during therapy with a very low calorie diet(VLCD)and subsequent rebound of body weight were more frequently observed in patients with relatively less healthy personalities. We used this classification to adapt our pro gram to treat obese patients. In this program, severe diet restrictions were applied to patients with relatively healthy personalities. These restrictions were applied with modifications to patients with less healthy personality, because severe restrictions would be possibly very stressful for them and would bring about an undesirable reaction. For strengthening the patients' motivation for therapy, the significance of body weight reduction was explained in different ways to patients with different types of personality. The target of body weight reduction, reward for patients with successful weight reduction, and the duration of therapy were setup differently for patients with different personalities types. The results showed that body weight rebound one or two years after treatment was reduced with the personality-oriented therapy pro gram compared to that observed with the previous conventional therapies. Also, the incidence of psychological problems was remarkably decreased. 相似文献
607.
Harazono A Kawasaki N Itoh S Hashii N Matsuishi-Nakajima Y Kawanishi T Yamaguchi T 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2008,869(1-2):20-30
Changes in the glycosylation of some serum proteins are associated with certain diseases. In this study, we performed simultaneous site-specific glycosylation analysis of abundant serum glycoproteins by LC/Qq-TOF MS of human serum tryptic digest, the albumin of which was depleted. The glycopeptide peaks on the chromatogram were basically assigned by database searching with modified peak-list text files of MS/MS spectra and then based on mass differences of glycan units from characterized glycopeptides. Glycopeptide of IgG, haptoglobin and ceruloplasmin were confirmed by means of a comparison of their retention times and m/z values with those obtained by LC/MS of commercially available glycoproteins. Mass spectrometric carbohydrate heterogeneity in the assigned glycopeptides was analyzed by an additional LC/MS. We successfully demonstrated site-specific glycosylation of 23 sites in abundant serum glycoproteins. 相似文献
608.
Masakazu Goto Chisato Ito Mohammed Sani Yahaya Yoshihito Wakai Shiro Asano Yukari Oka Satoru Ogawa Masami Fruta Teruo Kataoka 《Marine and Freshwater Behaviour and Physiology》2004,37(2):99-107
The number of microorganisms in the hindgut of dugongs (Dugong dugon) were estimated and their in vitro volatile fatty acid (VFA) production and degradation of eelgrass measured. Scanning electron microscopy showed that some rod bacteria attached to the surface of plant tissue degraded and eroded the cell walls. Number of starch-, lactate-, cellobiose-, pectin-, xylan- and cellulose-utilizing bacteria, sulfate-reducing bacteria and methane-producing bacteria were estimated at 109 ∼ 1010 colony forming units g-1. Microorganisms degraded the cellulose and noncellulolytic components of the eelgrass, and about 47.3% of dry matter was degraded after 36 h in vitro incubation. The total VFA concentration was 10.5 mmol dL-1 at 36 h incubation, which included 55.7 mol% acetate, 18.0 mol% n-butyrate and 15.1 mol% propionate. The gas composition of in vitro fermentation was 68.4% carbon dioxide, 22.2% methane and 9.4% hydrogen. 相似文献
609.
The risk of birth defects in dichorionic twins conceived by assisted reproductive technology. 总被引:1,自引:0,他引:1
Tomoyuki Kuwata Shigeki Matsubara Akihide Ohkuchi Takashi Watanabe Akio Izumi Yoko Honma Yukari Yada Hiroaki Shibahara Mitsuaki Suzuki 《Twin research》2004,7(3):223-227
The purpose of this study was to examine whether dichorionic twins conceived by assisted reproductive technology (ART; intracytoplasmic sperm injection [ICSI], in vitro fertilization [IVF], gamete-intrafallopian tube transfer [GIFT]) have a higher risk of birth defects compared to dichorionic twins conceived naturally. We reviewed the medical records of 406 mothers with dichorionic twin pregnancies, who received continuous antenatal care from < or = 20 weeks of gestation and gave birth to infants after > or = 24 weeks of gestation in our institute. Birth defects were diagnosed at the time of hospital discharge according to the International Classification of Diseases, 10th Revision. Occurrence of birth defects was compared between twins conceived by ART and those conceived naturally using logistic regression analysis. Overall, 51 of 812 infants (51/812 = 6.2%) had birth defects. The incidence of birth defects in ART-conceived twins was significantly higher than that of naturally conceived twins with an odds ratio of 6.9 (95% confidence interval [CI] 2.1, 22.5), 3.7 (95% CI 1.2, 12.0), and 4.3 (95% CI 1.4, 14.3) for ICSI, IVF, and GIFT, respectively. The higher frequency of birth defects in ART-conceived twins was still significant after adjusting for higher maternal age in the ART group, with an adjusted odds ratio of 6.7 (95% CI 2.1, 21.9), 3.6 (95% CI 1.1, 11.5), and 3.7 (95% CI 1.2-11.8) for ICSI, IVF, and GIFT, respectively. Dichorionic twins conceived by ART, compared to dichorionic twins conceived naturally, had a much higher risk for birth defects diagnosed at hospital discharge. 相似文献
610.
Yamasaki M Tachibana H Yamada A Ochi Y Madhyastha H Nishiyama K Yamada K 《In vitro cellular & developmental biology. Animal》2008,44(7):290-294
Our previous study indicated that oleic acid prevented apoptotic cell death induced by trans10, cis12 (t10, c12)-conjugated linoleic acid in rat hepatoma dRLh-84 cells. The intracellular mechanism of action oleic acid is still unknown. Here, we showed that p38 mitogen-activated protein kinase (MAPK) inhibition using its specific inhibitor SB203580 cancelled the ameliorative effect of oleic acid on the cytotoxicity of t10, c12-conjugated linoleic acid. In addition, SubG1 cell population analysis showed that p38 MAPK played an essential role in the prevention of apoptotic cell death by oleic acid. In fact, p38 phosphorylation level was upregulated in cells treated with oleic acid irrespective of t10, c12-conjugated linoleic acid stimulation. Interestingly, t10, c12-conjugated linoleic acid increased intracellular triglyceride accumulation. However, oleic acid completely inhibited this effect. These observations indicated the involvement of blockade of a p38 MAPK pathway in the ameliorative effect of oleic acid on apoptosis induced by t10, c12-conjugated linoleic acid. 相似文献