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291.
BT Heniford SO Senler JM Olsofka EH Carrillo TM Bergamini 《Canadian Metallurgical Quarterly》1998,12(5):482-486
In the winter of 1996, a total of 71 working adults from 20 to 60 (m = 37.3) years of age were immunized with one or two doses of inactivated influenza vaccine formulated in Japan. The reciprocal geometric mean hemagglutination inhibition antibody titers [mean HI] and the percentage with a hemagglutination inhibition titer of > or = x 128 [percent > or = x 128], against A/ Yamagata/32/89 (H1N1), A/Uhan/359/95 (H3N2), and B/Mie/1/93 were significantly elevated by either doses. The pre-/post-vaccination mean HI of H1N1 were 61.5/668.4 with one dose, and 85.7/637.3 with two doses. The percent > x 128 were 36.5/96.2 with one dose, and 47.4/94.7 with two doses. No significant differences were apparent between one and two doses. Similarly, nonsignificant differences were observed for the other two antigens contained in the vaccine. We observed the sufficient immune response to only one dose of inactivated influenza vaccine, which emphasizes the merit of one dose method of influenza immunization. 相似文献
292.
H Hawighorst W Weikel PG Knapstein MV Knopp I Zuna SO Sch?nberg P Vaupel G van Kaick 《Canadian Metallurgical Quarterly》1998,4(10):2305-2312
Angiogenesis plays a fundamental role in tumor growth and metastasis. What is needed is a quantitative, noninvasive, and repeatable assay to estimate functional angiogenic activity of the entire tumor. The aims of the present study were to: (a) examine the relationship between functional magnetic resonance imaging (MRI)-based parameters with established histomorphological markers of tumor angiogenesis [histological microvessel density (HMVD) and vascular endothelial growth factor expression (VEGF)]; and (b) determine the ultimate value of both approaches to assess functional angiogenic active hotspots as markers of disease outcome in patients with cancer of the uterine cervix. Pharmacokinetic parameters (amplitude A, tissue exchange rate constant k21) were calculated from contrast-enhanced dynamic MRI series in 57 patients (mean age, 49 +/- 14 years) with biopsy proven uterine cervical cancer. Both pharmacokinetic parameters were correlated to histomorphologically determined areas of high HMVD and VEGF expression obtained from the operative specimens after radical surgery. In addition, the functional MRI and histomorphological data were used to assess disease outcome. A significant association was found between HMVD and the amplitude A (P < 0.001) and a less pronounced association with k21, (P < 0.05), respectively. No significant associations were found between the pharmacokinetic parameters (A, k21) and VEGF expression. When stratified into high and low median k21 groups, median k21 values >5.4 min(-1) were the only significant (P < 0.05) factors in predicting poor patient survival. None of the histomorphological markers of angiogenesis (HMVD or VEGF expression) showed any predictive power. We have found that: (a) focal hotspots of HMVD are the pathophysiological basis for differences in functional MRI; (b) areas of high microvessel density and microvessel permeability do not necessarily coincide, as demonstrated by the histomorphological and functional MRI findings; (c) the functional angiogenic activity of a tumor may not be sufficiently characterized by a histomorphological approach but rather by a functional MRI-based approach; and (d) functional MRI-based analysis may assess tumor angiogenic activity in terms of disease outcome more comprehensively than the histomorphological approach. 相似文献
293.
Long-term trends in incidence, survival and mortality were examined in women with squamous cell carcinoma and adenocarcinoma of the uterine cervix, diagnosed in Norway in the 35-year period 1956-1990. During the 1970s the number of cervical smears increased substantially in Norway, although no organised screening programme was introduced. Special attention was paid to the time period 1971-1990 to evaluate the effect of the extensive spontaneous screening. In addition, the prognostic importance of clinical stage and age was explored. In the squamous cell carcinoma patients the incidence rate peaked in the time period 1971-1975, since when there has been a decrease. In the adenocarcinoma patients the incidence rate rose through the years 1976-1990. Also, the proportion of adenocarcinomas increased in this time period. The mortality rates in both histological types declined modestly through the years 1966-1990. A more favourable stage distribution was noted among the squamous cell carcinomas (P = 0.00), but not among the adenocarcinomas, when comparing the two diagnostic periods 1971-1975 and 1981-1985. The multivariate analysis (GLIM) revealed that stage was the most important prognostic factor in both histological types (P = 0.00). In the squamous cell carcinoma patients the relative rate increased (P = 0.04) in the last period. There was a tendency towards a poorer prognosis in younger women in this group, but age did not prove to be an important prognostic factor (P = 0.08). 相似文献
294.
SO Rhee 《Canadian Metallurgical Quarterly》1977,15(7):568-577
This study has attempted to determine the relationship between physicians' medical education and their performances (technical quality and utilization of medical care resources) in offices and hospitals. The sample consisted of 506 physicians of Hawaii, involving 18 specialty categories. The study finds little evidence of the influence of the type of medical schools on physicians' technical quality and utilization of medical resources in practice. The mean differences between the categories of medical schools were not statistically significant (except for the quality when specialists practiced within their own areas of specialization). There is no evidence that all categories of U.S. medical graduates provided a higher quality care and better utilization than all categories of foreign medical graduates. There was no consistent pattern of performances within the categories of U.S. medical schools and of foreign medical schools in these dimensions of performances. 相似文献
295.
Laura Blanco Martín Michel Tijani Faouzi Hadj-Hassen 《Construction and Building Materials》2011,25(2):749-755
A new analytical approach able to predict the mechanical behaviour of fully grouted rockbolts subjected to pull-out tests is proposed in this paper. Input parameters of such approach are: bolt radius, bolt’s Young modulus, displacement of the free end of the bolt and the constitutive law of the rockbolt–grout joint interface. The limited circumstances under which it is accurate to determine such constitutive law from pull-out tests are also presented. A solution for the load–displacement curve obtained during pull-out tests has been developed and is detailed in the case of a tri-linear bond-slip model. Comparison with experimental results obtained via in situ pull-out tests has led to the validation of this approach. 相似文献
296.
297.
The influence of deposition conditions on structural and electrical properties of amorphous gallium arsenide (a-GaAs) thin films, deposited by RF sputtering at two substrate temperatures (glass substrates) and (Mo and ITO/glass substrates), is studied by both X-ray diffraction and electrical dark conductivity σ measurements, in the range (−150 °C to +150 °C) of temperature.The increase of sputtering argon pressure, PAr, leads to the growth of an amorphous structure and reduces the room-temperature dark conductivity, σRT, which suggests a reduction in the density of defects. Similar results are obtained with a decrease of the dc self-bias voltage, Vp, of RF electrodes. These results suggest that the density of defects is reduced with the energy decrease of the bombarding species while increasing PAr or decreasing Vp. The product of the target-to-substrate distance by the argon pressure, (d×PAr), representing the number of particles free path, confirms some results of the literature which indicate that the density of defects can be reduced significantly by reducing the energy of the bombarding species while increasing PAr or decreasing Vp. Materials of great resistivity (≈108 Ω cm) are obtained either for low Vp or for great d×PAr. In addition, the thermal annealing reduces considerably the room-temperature dark conductivity. 相似文献
298.
We explore the potential use of the Fourier-transform profilometry technique in in vivo studies of muscular contractions through the variation of muscle-group cross sections. Thanks to a tensorial analysis of the technique, a general expression of its sensitivity vector is established. It allows derivation of the expression of the resolution and the limit condition imposed by the spatial sampling of the fringe pattern. Key parameters that maximize the sensitivity are then simulated. A measurement system is accordingly built up and characterized. It is then successfully applied to the evaluation of the deformation of the forearm muscles during grasping exertions. 相似文献
299.
SO Porto DD Cardoso DA Queiróz H Rosa AL Andrade F Zicker CM Martelli 《Canadian Metallurgical Quarterly》1994,15(7):577-581
PURPOSE: A seroprevalence survey was carried out among 496 street adolescents from 9 to 20 years old in central Brazil to determine the prevalence of hepatitis B (HBV) markers, as well as to assess the role of potential risk factors. RESULTS: The findings reveal that 20.4% of the participants were homeless adolescents without family links, living and/or working on the streets. The age at first sexual intercourse was as low as 9 years old, and approximately 60% of this population had had at least one sexual relationship by the age of thirteen, indicating prepubertal initiation of sexual experiences among street adolescents. 13.5% were HBV marker-positive (anti-HBc) and 2.0% had antigenemia. Street-based youth had a higher HBV marker-positive rate when compared to home-based teens (OR = 4.1, 95% CI: 2.1-8.5) and, similarly, higher HBV prevalence was obtained for those reporting sexual activity versus the group without sexual activity (OR = 2.1, 95% CI: 1.1-3.9), even after adjusting for potential confounders. CONCLUSIONS: We have found that street youth, particularly street-based adolescents, should be considered at-risk group for hepatitis B infection in our region. These findings may be used as a baseline information for policy changes not only in hepatitis B prevention but also to reverse the scenario of adolescents sexual abuse. 相似文献
300.
MP Fink DR Snydman MS Niederman KV Leeper RH Johnson SO Heard RG Wunderink JW Caldwell JJ Schentag GA Siami 《Canadian Metallurgical Quarterly》1994,38(3):547-557
Intravenously administered ciprofloxacin was compared with imipenem for the treatment of severe pneumonia. In this prospective, randomized, double-blind, multicenter trial, which included an intent-to-treat analysis, a total of 405 patients with severe pneumonia were enrolled. The mean APACHE II score was 17.6, 79% of the patients required mechanical ventilation, and 78% had nosocomial pneumonia. A subgroup of 205 patients (98 ciprofloxacin-treated patients and 107 imipenem-treated patients) were evaluable for the major efficacy endpoints. Patients were randomized to receive intravenous treatment with either ciprofloxacin (400 mg every 8 h) or imipenem (1,000 mg every 8 h), and doses were adjusted for renal function. The primary and secondary efficacy endpoints were bacteriological and clinical responses at 3 to 7 days after completion of therapy. Ciprofloxacin-treated patients had a higher bacteriological eradication rate than did imipenem-treated patients (69 versus 59%; 95% confidence interval of -0.6%, 26.2%; P = 0.069) and also a significantly higher clinical response rate (69 versus 56%; 95% confidence interval of 3.5%, 28.5%; P = 0.021). The greatest difference between ciprofloxacin and imipenem was in eradication of members of the family Enterobacteriaceae (93 versus 65%; P = 0.009). Stepwise logistic regression analysis demonstrated the following factors to be associated with bacteriological eradication: absence of Pseudomonas aeruginosa (P < 0.01), higher weight (P < 0.01), a low APACHE II score (P = 0.03), and treatment with ciprofloxacin (P = 0.04). When P. aeruginosa was recovered from initial respiratory tract cultures, failure to achieve bacteriological eradication and development of resistance during therapy were common in both treatment groups (67 and 33% for ciprofloxacin and 59 and 53% for imipenem, respectively). Seizures were observed more frequently with imipenem than with ciprofloxacin (6 versus 1%; P = 0.028). These results demonstrate that in patients with severe pneumonia, monotherapy with ciprofloxacin is at least equivalent to monotherapy with imipenem in terms of bacteriological eradication and clinical response. For both treatment groups, the presence of P. aeruginosa had a negative impact on treatment success. Seizures were more common with imipenem than with ciprofloxacin. Monotherapy for severe pneumonia is a safe and effective initial strategy but may need to be modified if P. aeruginosa is suspected or recovered from patients. 相似文献