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31.
EL Alderman JH Levy JB Rich M Nili B Vidne H Schaff G Uretzky G Pettersson JJ Thiis CB Hantler B Chaitman A Nadel 《Canadian Metallurgical Quarterly》1998,116(5):716-730
OBJECTIVE: We examined the effects of aprotinin on graft patency, prevalence of myocardial infarction, and blood loss in patients undergoing primary coronary surgery with cardiopulmonary bypass. METHODS: Patients from 13 international sites were randomized to receive intraoperative aprotinin (n = 436) or placebo (n = 434). Graft angiography was obtained a mean of 10.8 days after the operation. Electrocardiograms, cardiac enzymes, and blood loss and replacement were evaluated. RESULTS: In 796 assessable patients, aprotinin reduced thoracic drainage volume by 43% (P < .0001) and requirement for red blood cell administration by 49% (P < .0001). Among 703 patients with assessable saphenous vein grafts, occlusions occurred in 15.4% of aprotinin-treated patients and 10.9% of patients receiving placebo (P = .03). After we had adjusted for risk factors associated with vein graft occlusion, the aprotinin versus placebo risk ratio decreased from 1.7 to 1.05 (90% confidence interval, 0.6 to 1.8). These factors included female gender, lack of prior aspirin therapy, small and poor distal vessel quality, and possibly use of aprotinin-treated blood as excised vein perfusate. At United States sites, patients had characteristics more favorable for graft patency, and occlusions occurred in 9.4% of the aprotinin group and 9.5% of the placebo group (P = .72). At Danish and Israeli sites, where patients had more adverse characteristics, occlusions occurred in 23.0% of aprotinin- and 12.4% of placebo-treated patients (P = .01). Aprotinin did not affect the occurrence of myocardial infarction (aprotinin: 2.9%; placebo: 3.8%) or mortality (aprotinin: 1.4%; placebo: 1.6%). CONCLUSIONS: In this study, the probability of early vein graft occlusion was increased by aprotinin, but this outcome was promoted by multiple risk factors for graft occlusion. 相似文献
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Electrocopolymerization of a binary mixture of 3‐chloroaniline and 2‐amino‐4‐phenylthiazole on platinum electrode in acid medium was carried out under different reaction conditions such as temperature, current density, hydrochloric acid, and monomer concentrations with duration time. The initial rate of the electrocopolymerization reaction on platinum electrode is small and the rate law is Rp = K2 [D]1.29[HCl]0.97[M]1.94. The apparent activation energy is found to be 38.87 kJ/mol. The obtained copolymer film is characterized by 1H‐NMR, elemental analysis, GPC IR, UV‐visible, and cyclic voltammetry and compared with those of the two homopolymers. The mechanism of the electrocopolymerization reaction is also discussed and the monomer reactivity ratio (r1and r2) is calculated. The thermogravimetric analysis (TGA) is used to confirm the proposed structure and determination of the number of water molecules in the polymeric chain unit. X‐ray and scanning electron microscopic analysis are used to investigate the surface morphology. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2076–2087, 2005 相似文献
34.
The subject matter and trends of presentations made at ASHP Midyear Clinical Meetings (MCMs) were studied. A computerized database of information from MCM and Annual Meeting (AM) program and abstract books was created. The data were analyzed to determine the distribution of MCM presentations by subject and by author for the period 1967 to 1990, determine if there were differences in subjects covered between MCMs and AMs, explore the proposition that there has been duplication of material in MCM presentations, and evaluate the frequency with which MCM presentations have been published in ASHP journals. The total number of presentations made at MCMs from 1967 through 1990 was 8180, while the total for the AMs was 1547 for the two periods (1962-71 and 1985-90) studied. The most common keywords in titles were "pharmacy," "drug," "patient," "hospital," and "service." All International Pharmaceutical Abstracts subject categories and two other categories were represented; presentations in the institutional pharmacy practice category were the most frequent, while pharmacognosy-related presentations were least frequent. The overwhelming number of authors made only one presentation and were listed as the first author. The subjects of presentations were similar between AMs and MCMs. A tendency toward duplication of material was found. Of the 8180 MCM presentations, at least 1005 were published in an ASHP journal. Between 1967 and 1990, presentations at MCMs covered a wide range of subjects but were sometimes duplicative or not on the cutting edge. 相似文献
35.
CM Otto MC Mickel JW Kennedy EL Alderman TM Bashore PC Block JA Brinker D Diver J Ferguson DR Holmes 《Canadian Metallurgical Quarterly》1994,89(2):642-650
BACKGROUND: To identify predictors of long-term outcome after balloon aortic valvuloplasty, we analyzed data on 674 adults (mean age, 78 +/- 9 years; 56% were women) undergoing this procedure at 24 clinical centers who had a mean initial increase in aortic valve area of 0.3 cm2. METHODS AND RESULTS: Baseline data included clinical, echocardiographic, and catheterization variables. Follow-up data included mortality, cause of death, rehospitalization, 6-month echocardiography, and functional status. Kaplan-Meier curves and log-rank tests were used to evaluate survival in subgroups. Multivariate Cox regression models were used to identify independent predictors of survival. Overall survival was 55% at 1 year, 35% at 2 years, and 23% at 3 years, with the majority of deaths (70%) classified as cardiac by an independent review committee. Rehospitalization was common (64%), although 61% of survivors at 2 years reported improved symptoms. Echocardiography at 6 months (n = 115) showed restenosis from the postprocedural valve area of 0.78 +/- 0.31 cm2 to 0.65 +/- 0.25 cm2 (P < .0001). With stepwise multivariate analysis, sequentially adding clinical, echocardiographic, and catheterization variables, the overall model identified independent predictors of survival as baseline functional status, baseline cardiac output, renal function, cachexia, female gender, left ventricular systolic function, and mitral regurgitation. Baseline and postprocedural variables were examined to identify which subgroup of patients has the best outcome after aortic valvuloplasty. A "lower-risk" subgroup (28% of the study population), defined by normal left ventricular systolic function and mild clinical functional limitation, had a 3-year survival of 36% compared with 17% in the remainder of the study group. CONCLUSIONS: Long-term survival after balloon aortic valvuloplasty is poor with 1- and 3-year survival rates of 55% and 23%, respectively. Although survivors report fewer symptoms, early restenosis and recurrent hospitalization are common. 相似文献
36.
J EL GHOUL 《Bulletin of Materials Science》2016,39(1):7-12
The synthesis by the sol–gel method, structural and optical properties of ZnO, Zn0.99Al0.01O (AlZ), Zn0.9V0.1O (VZ) and Zn0.89Al0.01V0.1O (AlVZ) nanoparticles was reported. The approach was slow release of water for hydrolysis by esterification reaction followed by a supercritical drying in ethyl alcohol. After thermal treatment at 500°C in air, the obtained nanopowders were characterized by various techniques such as transmission electron microscopy, X-ray diffraction and photoluminescence (PL) spectroscopy. The structural properties showed that the ZnO nanoparticles with an average particle size of 25 nm exhibit hexagonal wurtzite structure. From the optical studies, it was found that the optical band gap was located between 2.97 and 3.17 eV. The obtained electrical properties showed the potential application of the samples in optoelectronic devices. The powder of AlVZ presented a strong luminescence band in the visible range. The PL band energy position presented a small blue shift with the increase of measurement temperature. Different possible attributions of this emission band will be discussed. 相似文献
37.
EL Brandwene SR Williams C Tunget-Johnson SG Turchen AS Manoguerra RF Clark 《Canadian Metallurgical Quarterly》1996,14(6):691-695
Treatment of an acetaminophen overdose with N-acetyl cysteine usually is based on the position of the 4-h acetaminophen (APAP) level on the Rumack-Matthew nomogram; however, there is disagreement on the level at which clinically relevant hepatotoxicity occurs. A retrospective review of all acute adult formulation APAP exposures reported to our poison center between 1986 and 1993 was performed and cases corresponding to the "possible risk or toxicity" range on the nomogram were identified. Our current poison center protocol for APAP poisoning does not recommend treatment with N-acetylcysteine (NAC) in low-risk patients if the 4-h serum APAP level or the extrapolated equivalent falls within the possible toxicity range on the nomogram. Seventeen cases met the inclusion criteria for the study and received no NAC; six additional patients met inclusion criteria but received one or two doses of NAC before therapy was discontinued. No patients in either group demonstrated clinical evidence of hepatotoxicity. This pilot study suggests that patients with no risk factors and APAP levels in the "possible risk" range may not require NAC therapy. 相似文献
38.
Hany F. EL Yamany Miriam A.M. Capretz David S. Allison 《Information and Software Technology》2010,52(2):220-236
One of the most significant difficulties with developing Service-Oriented Architecture (SOA) involves meeting its security challenges, since the responsibilities of SOA security are based on both the service providers and the consumers. In recent years, many solutions to these challenges have been implemented, such as the Web Services Security Standards, including WS-Security and WS-Policy. However, those standards are insufficient for the new generation of Web technologies, including Web 2.0 applications. In this research, we propose an intelligent SOA security framework by introducing its two most promising services: the Authentication and Security Service (NSS), and the Authorization Service (AS). The suggested autonomic and reusable services are constructed as an extension of WS-1 security standards, with the addition of intelligent mining techniques, in order to improve performance and effectiveness. In this research, we apply three different mining techniques: the Association Rules, which helps to predict attacks, the Online Analytical Processing (OLAP) Cube, for authorization, and clustering mining algorithms, which facilitate access control rights representation and automation. Furthermore, a case study is explored to depict the behavior of the proposed services inside an SOA business environment. We believe that this work is a significant step towards achieving dynamic SOA security that automatically controls the access to new versions of Web applications, including analyzing and dropping suspicious SOAP messages and automatically managing authorization roles. 相似文献
39.
EL Wallace DM Surgenor HS Hao J An RH Chapman WH Churchill 《Canadian Metallurgical Quarterly》1993,33(2):139-144
A poor response to L-DOPA in addition to parkinsonian, cerebellar, and autonomic signs is commonly regarded as indicative of clinical multiple system atrophy (MSA). We compared the motor response to a single oral administration of 250 mg L-DOPA/25 mg carbidopa in eight MSA patients and eight Parkinson's disease (PD) patients with the "on-off" phenomenon, evaluating L-DOPA peripheral pharmacokinetics. Motor response was consistently good in all PD patients, but only four MSA patients had a (moderate) response. Pharmacokinetic parameters did not differ between the groups. The varying extent of putaminal damage could be responsible for the differing motor response to L-DOPA in MSA patients. 相似文献
40.
NABIH N. ABDELMALEK 《International journal of control》2013,86(4):635-642
A simplex algorithm for solving the minimum fuel problem for linear discrete control systems is described. In this algorithm an initial basic feasible solution is available with no artificial variables needed. Also minimum computer storage is required. The algorithm is a simple and fast one. A numerical example is given 相似文献