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71.
K Masuda Y Makino J Cui T Ito T Tokuhisa Y Takahama H Koseki K Tsuchida T Koike H Moriya M Amano M Taniguchi 《Canadian Metallurgical Quarterly》1997,158(5):2076-2082
A novel subset of peripheral T cells, peripheral NK T cells, is found to be a major population comprising 5% of splenic T and 40% of bone marrow T cells. The majority of peripheral NK T cells are characterized by the expression of an invariant TCR-alpha encoded by V alpha 14/J alpha 281 with a one nucleotide N region. Moreover, a specific reduction of V alpha 14+ NK T cells has been demonstrated to be tightly associated with various autoimmune diseases, indicating their decisive role in autoimmune disease development. In this study, we investigated the phenotypes of peripheral V alpha 14+ NK T cells and their TCR-beta repertoire. Peripheral V alpha 14+ NK T cells, comprise two populations, i.e., small and large sized cells, at an equal frequency, belonged to the CD4- CD8- fraction, and are heat stable antigen(bright), macrophage-1bright, B220bright, CD45RBdim, and Mel-14dim, but CD5-, distinct from thymic NK T cells. TCR-beta analysis clearly showed that peripheral V alpha 14+ NK T cells utilized two to three dominant invariant TCR-beta, such as V beta 8.2 D beta J beta 2.5/V beta 7 D beta J beta 2.1 in the spleen and liver, V beta 8.2 D beta J beta 2.5/V beta 8.3 D beta J beta 2.2/V beta 7 D beta J beta 2.6 in the bone marrow, and V beta 7 D beta J beta 2.1/V beta 3 D beta J beta 1.2 in intestinal intraepithelial lymphocytes. Judging from the unusual surface phenotypes, such as heat stable antigen, macrophage-1, B220, CD45RBdim, and Mel-14dim, which are known to be T cell activation markers, peripheral V alpha 14+ NK T cells may always be activated under physiologic conditions, resulting in the oligoclonal expansion of V alpha 14+ NK T cells with different invariant TCR-beta in different peripheral organs. The unique features of V alpha 14+ NK T cells are discussed. 相似文献
72.
T Takahashi S Yagishita N Amano K Yamaoka T Kamei 《Canadian Metallurgical Quarterly》1997,94(3):294-299
The use of biomarkers is a promising approach to the study of human cancer risk. Bronchial metaplasia in sputum cytology may be a marker for potential premalignancy that can be used for population studies. We recently performed a randomized, controlled trial in smokers on the effect of 14 weeks beta-carotene (20mg/day) on markers for DNA damage. We now have evaluated the application of sputum cytology in this study and performed a preliminary evaluation of the effect of beta-carotene. Of the 150 potential participants in this trial 75 were not eligible because they failed to produce sputum samples (n = 29), or because samples were unsatisfactory (n = 46). The eligible group was older (41 vs 37 years) and had smoked longer (23 vs 19 years), but had similar cigarette consumption (mean 21/day) and plasma cotinine levels. Metaplasia was graded in seven categories. Only 11 subjects (15%) showed minor or mild atypia on study entry. Agreement within and between observers was 95% within the same or an adjacent category. We observed no significant correlation between before and after treatment final metaplasia scores in either the beta-carotene (Spearman R = 0.18, P = 0.3) or placebo group (Spearman R = 0.17, P = 0.3). Initial metaplasia scores were somewhat higher in the beta-carotene group (n = 33) than in the placebo group (n = 42) (P = 0.06). Final metaplasia scores were similar in both groups (P = 0.69), and there was no decrease in metaplasia scores in the beta-carotene group (P = 0.75). This study indicates that sputum cytology may not yet be a readily applicable marker in studies of a healthy asymptomatic population, because many smokers do not spontaneously produce sputum, more severe lesions are rare, and variation over time in the minor lesions in large. Therefore, the preliminary evidence that beta-carotene has no influence should be interpreted with care. 相似文献
73.
T Imada Y Ozawa J Minamide Y Rino M Takahashi M Shiozawa S Hatori Y Suzuki T Amano 《Canadian Metallurgical Quarterly》1998,45(24):2224-2227
BACKGROUND/AIMS: Close observation and evaluation of the function of the transposed stomach after esophagectomy is essential. The present study uses the sulfamethizole capsule meal test to evaluate differences in gastric emptying between the anterior and posterior mediastinal approaches in patients undergoing esophagectomy. METHODOLOGY: Thirty-eight patients who underwent the esophagectomy and esophagogastrostomy for esophageal cancer were randomly divided into 2 groups: Group 1: anterior mediastinal approach, and Group 2: posterior mediastinal approach. Gastric emptying was studied using the sulfamethizole capsule meal test. Patients received sulfamethizole food capsules, 65 g of bread, and 150 ml of water. Plasma sulfamethizole levels were determined by high performance liquid chromatography (HPLC). RESULTS: Gastric emptying in both groups was significantly accelerated compared to healthy volunteers. Gastric emptying did not differ significantly between groups 1 and 2. CONCLUSIONS: The present data show that the sulfamethizole capsule meal test is an effective means of evaluating the emptying of the transposed stomach. Furthermore, when the stomach is used as an esophageal substitute following esophagectomy, gastric emptying does not differ according to the access route. 相似文献
74.
A Amano HT Sojar JY Lee A Sharma MJ Levine RJ Genco 《Canadian Metallurgical Quarterly》1994,62(8):3372-3380
Fimbriae are considered important in the adherence and colonization of Porphyromonas gingivalis in the oral cavity. It has been demonstrated that purified fimbriae bind to whole human saliva adsorbed to hydroxyapatite (HAP) beads, and the binding appears to be mediated by specific protein-protein interactions. Recently, we expressed the recombinant fimbrillin protein (r-Fim) of P. gingivalis corresponding to amino acid residues 10 to 337 of the native fimbrillin (A. Sharma, H.T. Sojar, J.-Y. Lee, and R.J. Genco, Infect. Immun. 61:3570-3573, 1993). We examined the ability of individual salivary components to promote the direct attachment of r-Fim to HAP beads. Purified r-Fim was radiolabeled with 125I and incubated with HAP beads which were coated with saliva or purified individual salivary components. Whole, parotid, and submandibular-sublingual salivas increased the binding of 125I-r-Fim to HAP beads. Submandibular-sublingual saliva was most effective in increasing the binding of 125I-r-Fim to HAP beads (1.8 times greater than that to uncoated HAP beads). The binding of 125I-r-Fim to HAP beads coated with acidic proline-rich protein 1 (PRP1) or statherin was four and two times greater, respectively, than that to uncoated HAP beads. PRP1 and statherin molecules were also found to bind 125I-r-Fim in an overlay assay. The binding of intact P. gingivalis cells to HAP beads coated with PRP1 or statherin was also enhanced, by 5.4 and 4.3 times, respectively, over that to uncoated HAP beads. The interactions of PRP1 and statherin with 125I-r-Fim were not inhibited by the addition of carbohydrates or amino acids. PRP1 and statherin in solution did not show inhibitory activity on 125I-r-Fim binding to HAP beads coated with PRP1 or statherin. These results suggest that P. gingivalis fimbriae bind strongly through protein-protein interactions to acidic proline-rich protein and statherin molecules which coat surfaces. 相似文献
75.
T Amano 《Canadian Metallurgical Quarterly》1996,85(5):659-662
Baclofen is used for the treatment of post-traumatic spasticity. It carries a risk of overdose as well as of an acute withdrawal syndrome. We report two cases of severe hypertonia and hyperthermia (> 42 degrees C), occurring after accidental discontinuation of intrathecal infusion of baclofen. Both hypertonia and hyperthermia ceased when administration of baclofen was resumed. In parallel, the patients developed transient life-threatening alterations of hepatic (cytolysis), haematologic (coagulopathy) and cardiorespiratory functions for some days. It is concluded that the occurrence of such a withdrawal syndrome should be prevented, especially in patients with chronic intrathecal administration and first symptoms should be recognized without delay. Relationships with other malignant hyperthermias are discussed. 相似文献
76.
Fumiaki Machihara 《Performance Evaluation》1988,8(4):243-253
This paper presents an analysis of overflow processes from a PH1 + PH2/M/S/K queue having two independent phase type renewal input streams. Both the superposed overflow process and individual overflow processes for the PH1- and PH2-streams are analyzed using first passage time distributions for the number of customers in the system. Each overflow process is characterized as a Markov renewal process. The nth moment of the number of customers in an infinite server group to which these overflows have been offered is derived using a theory for the MR/M/∞ queue with a Markov renewal input. The numerical examples for means and variance-to-mean ratios (peakednesses) of the individual overflow streams are given for an H2 + H2/M/S/S queue with interrupted Poisson inputs, which is a vital model for telephone network planning. In addition, overflow traffic characteristics are discussed by using these examples. 相似文献
77.
Kinuhata K. Sasaki H. Yamamoto H. Amano K. 《Communications, IEEE Transactions on》1978,26(10):1413-1420
This paper introduces a new technique for TV standards conversion called "adaptive intra-frame line interpolation". The configuration and the performance of a digital converter developed by using the technique are also described. In the present converter, an input picture is divided into still and moving areas by measuring frame difference signals, and suitable interpolation parameters are adaptively chosen for each area. This method brings good results to both areas. Especially, the converter has enabled the converted picture to recover high vertical resolution of more than 350 TV lines in still pictures, which has never been obtained by any conventional intra-field line interpolation. 相似文献
78.
K Shimada H Kimura S Kudoh M Mohri T Shiraishi Y Amano A Kurashima T Uzawa T Hisada T Nagata 《Canadian Metallurgical Quarterly》1993,46(2):184-191
We report that the results of clinical studies on ceftriaxone (CTRX) in respiratory tract infections (RTIs). Clinical efficacies and side effects of CTRX were as follows; 1. Clinical efficacies of CTRX in a total of 61 cases with RTIs were excellent in 11 cases, good in 23, fair in 11, poor in 12 and unknown in 4. Thus the overall clinical efficacy rate was 59.6%. In cases of patients with lung cancers, the efficacy rate was 42.9%. 2. Clinical efficacy rates with once daily dosage were 50.0% with a dose level of 1 g CTRX and 54.8% with that of 2 g CTRX. 3. Side effects were observed in 2 cases (3.1%) and laboratory abnormalities were observed in 1 case (1.6%). They were not serious, however. These data suggest that CTRX is one of the useful cephalosporins in treatment of RTIs. 相似文献
79.
Jisun Jin Toshinobu Yoko Fumiaki Miyaji Sumio Sakka Toshiharu Fukunaga Masakatsu Misawa 《Journal of the American Ceramic Society》1993,76(3):630-634
The local structure of a Na2 O─SiO2 oxide glass and a Na2 O─iO2 ─Si3 N4 oxynitride glass has been investigated by the pulsed neutron diffraction method. In the oxide glass, the first peak of radial distribution function (RDF) curves appeared at 0.1627 nm corresponding to Si─O boxh length. In the oxynitride glass, the first peak of the RDF curve was shifted to longer distances at 0.1650 nm due to the coexistence of Si─O and Si─N boxhs. The first peak in the RDF curve of the oxynitride glass was deconvoluted into two peaks whose positions are located at 0.1626 and 0.1709 nm. The one at 0.1626 nm is ascribed to Si─O boxhs and the other at 0.1709 nm to Si─N boxhs. The number of silicon atoms around a nitrogen was found to be 2.42, suggesting that not all of the nitrogen atoms are boxhed to three silicon atoms, but 58% twofold (─N─) and 42% threefold (>N─) nitrogens coexist in the present Na-Si-O-N oxynitride glass. The formation of twofold nitrogens may arise from the reaction between ≡Si─O− and ≡Si3 N groups. This model is compatible with the experimental observation that the density and Vickers hardness of oxynitride glasses increase with the nitrogen content. 相似文献
80.
The pathogenicities of Haemophilus parasuis strains SW124 (serovar 4) and Nagasaki (serovar 5) were examined by contact-exposure of specific pathogen-free (SPF) pigs. Ten pigs were divided into three groups. Two of four pigs in the first group were inoculated intranasally (IN) with 2 x 10(8) CFU of strain SW124, and the other two pigs were mingled with these IN-exposed ones. All the four pigs were subclinically infected in this group. The four pigs of the second group were likewise exposed to strain Nagasaki (two IN-inoculated pigs with 3 x 10(8) CFU of strain Nagasaki). All four pigs in this group died of Gl?sser's disease. Two pigs kept as controls showed neither abnormality nor positive H. parasuis isolation. 相似文献