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121.
CD Jun BM Choi Hoon-Ryu JY Um HJ Kwak BS Lee SG Paik HM Kim HT Chung 《Canadian Metallurgical Quarterly》1994,153(8):3684-3690
The role of protein kinase C (PKC) in the induction of nitric oxide (NO) synthesis in murine peritoneal macrophages was examined. Phorbol ester, a PKC activator, had no effect on NO synthesis by itself, whereas IFN-gamma alone had modest activity. When phorbol ester was used in combination with IFN-gamma, there was a marked cooperative induction of NO synthesis in a dose-dependent manner. This increase in NO synthesis was reflected as increased amount of inducible NO synthase (iNOS) mRNA, as determined by Northern blotting. The optimal effect of phorbol ester was shown at 6 h after treatment with IFN-gamma. Phorbol ester also induced the release of NO to the incubation medium by bacillus Calmette-Guerin-infected peritoneal macrophages. Prolonged incubation of cells with phorbol ester, which down-regulates PKC activity, abolished the synergistic cooperative effect on NO production with IFN-gamma. In addition, such PKC inhibitors as staurosporin or polymyxin B reduced NO production induced by IFN-gamma plus phorbol ester. When the cells were treated with both actinomycin D and phorbol ester after IFN-gamma stimulation, more NO was produced and more iNOS mRNA was expressed than in the cells treated with actinomycin D alone. On the basis of these observations, we conclude that PKC might not be directly involved in the expression of NO synthase, but, instead, might be involved in the stabilization of the iNOS mRNA already expressed by the treatment of IFN-gamma. 相似文献
122.
YF Yen B Brinkm?ller D Dehnhard MA Franey SM Sterbenz YJ Yu B Berman GR Burleson K Cranston A Klein GS Kyle R Alarcon T Averett JR Comfort JJ G?rgen BG Ritchie JR Tinsley M Barlett GW Hoffmann K Johnson CF Moore M Purcell H Ward A Williams JA Faucett SJ Greene JJ Jarmer JA McGill CL Morris SI Penttil? N Tanaka HT Fortune E Insko R Ivie JM O'Donnell D Smith MA Khandaker S Chakravarti 《Canadian Metallurgical Quarterly》1994,50(2):897-908
123.
Symptoms of hereditary angioedema may present during the child's first years. Attacks may be a particular threat to the narrower airway of the child. An early diagnosis is most valuable because effective C1 inhibitor (C1 INH) concentrate is available. We present a reference area for the antigenic and functional determination of C1 INH by using uncontaminated umbilical cord blood from 80 normal newborns collected by puncturing vessels in the newly delivered placenta. We examined two full-term babies (1 and 2) from mothers with hereditary angioedema type I the same way. The concentration of C1 INH antigen was determined by radial immunodiffusion. The C1 INH functional assay was based on the addition of a known quantity of C1s, which enzymatically splits a chromogenic substrate. The test was performed in the presence of methylamine and heparin in a kinetic microtiter plate assay. Citrated plasma was used in both assays. The data obtained in the 80 cord blood samples (2.5-97.5 percentile) were 0.11-0.22 g/L for C1 INH antigen (adults, 0.15-0.33 g/L) and 47.2-85.9% for C1 INH function (percentage of adults). In cord blood, baby 1 had an antigenic value of 0.12 g/L (7.5 percentile) and C1 INH function of 61.8% (42 percentile). The corresponding values for baby 2 in cord blood were less than 0.05 g/L (0.106 g/L < 2.5 percentile) and 34.3% (12.9% < 2.5 percentile). Baby 2 had markedly lower C4 values yet much higher C4 activation products than baby 1. At 4 mo, baby 1 had an antigenic C1 INH value of 0.24 g/L.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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126.
The severity of lung inflammation in 34 patients with systemic lupus erythematosus (SLE) was measured by quantitative 67Ga-citrate lung scanning. The severity of lung inflammation in SLE was represented by the 67Ga uptake index (GUI). Quantitative 67Ga lung scanning was also performed on 20 normal controls for comparison with the SLE patients. The patients were divided into two subgroups according to the following two criteria: (a) stable or flare stage according to clinical features; or (b) positive or negative results of chest X-ray. The GUI values of the subgroups were also compared. The results revealed a trend towards higher values of GUI in SLE patients than in the normal controls. The GUI values were also higher for SLE cases with a flare stage or a negative chest X-ray than in SLE cases with a stable stage or a positive chest X-ray. The statistical results reveal that the differences in the GUI values are not significant. However, we found that (1) positive chest X-ray findings may be a later manifestation of a lung inflammation and (2) the values of GUI parallel clinical features in SLE patients. 相似文献
127.
The article explores the relationship between the cost and the quality of hospital care by elaborating a conceptual model of hospital performance. The model relates the financial health status of an organization (financial integrity) to the quality of care provided by that organization (clinical integrity) within an environment that is characterized by various forms of risk. The model suggests that both concepts determine the corporate destiny (success, bankruptcy, or merger) of the organization. If this model proves valid empirically, the results could be used as an early warning system to identify hospitals that might experience financial or clinical distress. 相似文献
128.
YB Min EM Finnegan HT Hoffman ES Luschei TM McCulloch 《Canadian Metallurgical Quarterly》1994,111(6):770-775
Confidence in the reliability of laryngeal electromyography to predict recovery is critical if this tool is to be used to select the type and timing of surgical intervention. The characteristics of electromyography of 14 patients with unilateral vocal fold paralysis were assessed to determine which factor or combination of factors would be most useful in determining prognosis. We examined the duration, amplitude, waveform morphology, root-mean-square, and time interval from onset to electromyography recording. The results supported the concept that electromyography recordings are valuable in determining prognosis if performed before 6 months and preferably within 6 weeks of onset of laryngeal paralysis. A positive prognosis for laryngeal recovery was indicated when the following electromyography features were present in the immobile vocal fold: (1) normal motor unit waveform morphology, (2) overall electromyography activity characterized by a root-mean-square value greater than 40 microV in any one task, and (3) no electrical silence during voluntary tasks. On the basis of this criteria our overall correct prognostic rate was 89%. 相似文献
129.
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