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排序方式: 共有610条查询结果,搜索用时 15 毫秒
61.
Protein phosphorylation/dephosphorylation on tyrosine residues are regulated by tyrosine kinases/phosphatases. The tyrosine phosphatase SH-PTP2 (PTP1D, PTP2C) interacts physically through its SH2 domain with phosphorylated epidermal growth factor receptor (EGFR). In KB cells, an oral epidermoid carcinoma, high epidermal growth factor (EGF) concentrations (10-9, 10-8 and 10-7 M) downregulate its receptor for the duration of the incubation with EGF. Thus, it was hypothesized that in KB cells, SH-PTP2 expression would also be downregulated by high EGF concentrations. This hypothesis was investigated by incubating the KB cells with increasing concentrations of EGF (0, 10-11, 10-10, 10-9, 10-8, 10-7 M) and by evaluating the expression of SH-PTP2 protein under these conditions. This study showed that EGF 10-7 and 10-8 M significantly decreased SH-PTP2 protein expression compared to controls. EGF 10-10 and 10-11 M did not change the expression of SH-PTP2 protein. We conclude that high EGF concentrations downregulate the expression of SH-PTP2 protein. 相似文献
62.
M Higashiyama O Doi K Kodama H Yokouchi R Tateishi K Kuriyama 《Canadian Metallurgical Quarterly》1996,26(9):747-750
We herein report an 83-year-old man who presented with a pleural tumor in the right thorax. The tumor was surgically resected and histopathologically diagnosed as ectopic primary pleural thymoma lacking any evidence of a mediastinal tumor. The clinicopathological aspects of this unusual thymoma are also discussed. 相似文献
63.
T Matsui M Maeda Y Doi S Yonemura M Amano K Kaibuchi S Tsukita S Tsukita 《Canadian Metallurgical Quarterly》1998,140(3):647-657
The ezrin/radixin/moesin (ERM) proteins are involved in actin filament/plasma membrane interaction that is regulated by Rho. We examined whether ERM proteins are directly phosphorylated by Rho-associated kinase (Rho-kinase), a direct target of Rho. Recombinant full-length and COOH-terminal half radixin were incubated with constitutively active catalytic domain of Rho-kinase, and approximately 30 and approximately 100% of these molecules, respectively, were phosphorylated mainly at the COOH-terminal threonine (T564). Next, to detect Rho-kinase-dependent phosphorylation of ERM proteins in vivo, we raised a mAb that recognized the T564-phosphorylated radixin as well as ezrin and moesin phosphorylated at the corresponding threonine residue (T567 and T558, respectively). Immunoblotting of serum-starved Swiss 3T3 cells with this mAb revealed that after LPA stimulation ERM proteins were rapidly phosphorylated at T567 (ezrin), T564 (radixin), and T558 (moesin) in a Rho-dependent manner and then dephosphorylated within 2 min. Furthermore, the T564 phosphorylation of recombinant COOH-terminal half radixin did not affect its ability to bind to actin filaments in vitro but significantly suppressed its direct interaction with the NH2-terminal half of radixin. These observations indicate that the Rho-kinase-dependent phosphorylation interferes with the intramolecular and/ or intermolecular head-to-tail association of ERM proteins, which is an important mechanism of regulation of their activity as actin filament/plasma membrane cross-linkers. 相似文献
64.
K Yamamoto S Kusachi Y Ninomiya M Murakami M Doi K Takeda T Shinji T Higashi N Koide T Tsuji 《Canadian Metallurgical Quarterly》1998,30(9):1749-1756
Biglycan, a small dermatan sulphate proteoglycan, has been postulated to interact with other components of the extracellular matrix (ECM), specifically collagens. We hypothesized that biglycan messenger ribonucleic acid (mRNA) is increased in the myocardial infarct zone. Biglycan mRNA expression after acute myocardial infarction (AMI) in rats was determined with the use of Northern blotting and in situ hybridization, and its expression pattern was compared to that of type I collagen mRNA [alpha1(I) collagen]. The left coronary artery was ligated in male Sprague-Dawley rats, and the hearts were excised on days 2 and 7. The Northern blot analysis demonstrated that expression of biglycan mRNA in the infarct on days 2 and 7 were 4.0- and 6.8-fold higher, respectively, compared to the sham-operated hearts. The in situ hybridization revealed intense signals for both biglycan and alpha1(I) collagen mRNA on day 2 in the spindle-shaped mesenchymal cells located between the surviving myocytes in the infarct peripheral zone. On day 7, biglycan mRNA signals were observed in the interior of the infarct around the infarct granulation tissue, a distribution that was essentially the same as that of alpha1(I) collagen. These results demonstrated that the increases in the infarct biglycan mRNA expression produced by mesenchymal cells (presumably myofibroblasts and fibroblasts) was closely co-localized with that of type I collagen mRNA, indicating that biglycan contributes to the infarct healing processes. 相似文献
65.
Anopheles tessellatus mosquitoes ingested Plasmodium vivax gametocytes in human erythrocytes suspended in rabbit sera with and without anti-mosquito midgut antibodies. When the mosquito bloodmeal contained anti-midgut antibodies, fewer oocysts of P.vivax developed on the mosquito midgut and the proportion of mosquitoes becoming infected was significantly reduced. Complement inactivated serum also reduced the infection rate and load. A second bloodmeal containing anti-midgut antibodies, given 48 or 72 h later, did not enhance the transmission-blocking effect. IgG purified from anti-midgut sera was shown to mediate the transmission-blocking effect. 相似文献
66.
H Yoshii M Sato S Yamamoto M Motegi S Okusawa M Kitano A Nagashima M Doi K Takuma K Kato N Aikawa 《Canadian Metallurgical Quarterly》1998,45(1):45-50; discussion 50-1
BACKGROUND: In the assessment of blunt abdominal trauma, the reliability of ultrasonography (US) in identifying individual organ injuries remains uncertain, in spite of its usefulness in detecting hemoperitoneum. This study was designed to evaluate the overall diagnostic value of US, including identification of individual organ injuries. METHODS: The accuracy of US in the detection of intra-abdominal injuries and the identification of individual organ injuries was evaluated in 1,239 patients seen during a 15-year period. Accuracy was based on detection of intraperitoneal fluid, free air, or irregular parenchymal lesions. RESULTS: For the detection of injuries, US was 94.6% sensitive, 95.1% specific, and 94.9% accurate. Individual organ injuries were identified with sensitivities of 92.4, 90.0, 92.2, 71.4, and 34.7% for the liver, spleen, kidneys, pancreas, and intestine, respectively. CONCLUSION: US is reliable for the detection of injuries and the identification of solid-organ injuries despite its poor sensitivity for intestinal injuries. 相似文献
67.
68.
S Morimoto A Hirano T Ohkawa J Doi A Suzuki K Hagino S Kitamura Y Sawada T Morita Y Miyazaki 《Canadian Metallurgical Quarterly》1995,41(4):245-251
One hundred and sixty one patients with upper urinary stones were examined for antimicrobial prophylaxis following extracorporeal shock wave lithotripsy (ESWL). They were divided into two groups, the low-risk group (n = 133) and high-risk group (n = 28), according to the risk factors of urinary tract infection. The patients in the low-risk group were further randomized into two groups which were orally given ofloxacin for 7 days after ESWL (Group A, n = 66), no antimicrobial (Group B, n = 67). The patients in the high-risk group were randomly subdivided into three groups which were given flomoxef intravenously for 2 or 3 days and ofloxacin for 4 or 5 days thereafter (Group C, n = 10), flomoxef only for 2 or 3 days and no drugs later (Group D, n = 10), ofloxacin for 7 days (Group E, n = 8). In all of the patients in the low-risk group, during the 7 days after ESWL, fever elevation was observed in only 1.5% of patients, and bacteriuria in 10.0% on the 7th day. There was no difference in frequency of fever elevation and bacteriuria following ESWL between Group A and Group B. These findings indicate that prophylactic antimicrobial after ESWL treatment is not necessary for low risk patients with urinary tract infections. In the high-risk group, the over-all rates of fever elevation and bacteriuria were 21.4% and 24.0% respectively. The difference of effectiveness among the prophylactic regimens of the three groups (Group C, D, E) was not shown.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
69.
Lakshmi Sharma Yoshino Ogino Toshiji Kanaya Tadahisa Iwata Yoshiharu Doi 《Journal of Materials Science》2006,41(17):5687-5695
In MMWT/UHMWT PHB blends (99.5/0.5), (99/1), (98/2) and (97/3) we demonstrate that by applying our new shear technique, “semi continuous shear flow”, copious fibre formation is guaranteed, irrespective of the ultra high molecular weight composition. The shishes formed via this technique are extremely stable being able to maintain their stability for at least 5–10 min. When this technique was applied to MMWT/UHMWT PHB blends of compositions (95/5), (90/10) and (85/15) disorientated fibres were observed in the flow direction. On increasing the UHMWT component, distinct unordered and intertwining of fibres resulted and with severe shearing orientation occurred, however shish formation was limited. We propose the optimum conditions for shish formation and the critical molecular weight necessary for entanglement. 相似文献
70.
Morphological examinations were carried out on hepatocyte nuclei of streptozotocin (SZ)-induced diabetic mice. The area of hepatocyte nuclei in diabetic mice was about two times larger than that in control mice, and the incidence of hepatocytes with intranuclear inclusions was 3.4 +/- 0.2% in diabetic mice and 0% in control mice, respectively. Although the incidence of binuclear hepatocytes was not significantly different between diabetic (14.5 +/- 4.6%) and control mice (16.4 +/- 4.4%), the morphology of the nuclei of binuclear hepatocytes was apparently different between diabetic and control mice. Namely, the nuclei of binuclear hepatocytes of control mice were round and identical in ultrastructural appearance, and they did not differ from those of mononuclear diploid hepatocytes. On the other hand, the nuclei of binuclear hepatocytes of diabetic mice were not identical in distribution pattern of chromatin granules, and they frequently varied in size and showed irregular contours. 相似文献