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991.
V Distante M Farouk TR Kurzawinski SW Ahmed AK Burroughs BR Davidson K Rolles 《Canadian Metallurgical Quarterly》1996,9(2):126-130
BACKGROUND: Use of non-steroidal anti-inflammatory drugs (NSAIDs) is recognized as an important cause of peptic ulcer complications. The aim of this nested case-control study was to identify risk factors for NSAID-related ulcer complications. METHODS: Cases were consecutive NSAID users admitted with an ulcer complication (n = 118), and controls were a random sample of all NSAID users without ulcer complication identified by a pharmacoepidemiologic database (n = 540). RESULTS: Ninety-four of 118 cases were interviewed, and 324 of 540 controls answered the questionnaire. Analysis showed no difference between included and non-included subjects. Risk factors for patients at start of NSAID therapy were high age: 60-75 years (odds ratio (OR), 3.5 (95% confidence interval (Cl), 1.8-7.1); > 75 years (OR, 8.9 (4.3-18.3)); male sex (OR 1.7 (1.0-3.0)); ulcer history (OR 2.5 (1.2-5.1)); steroid treatment (OR 2.0 (0.8-4.6)); smoking (OR 1.6 (0.9-2.7)); and alcohol use (OR 1.8 (0.9-3.6)). Risk factors for patients receiving NSAID therapy were high age, male sex, ulcer history, smoking and, furthermore, dyspepsia (OR 2.0 (1.0-4.2)), especially NSAID-related dyspepsia (OR 8.7 (4.0-18.9)). Risk was lower for patients treated more than 3 months. CONCLUSION: Risk measured from this design can be shown to correlate strongly with the rate difference, a measure that is more clinically relevant than conventional relative risk estimates. Strong risk factors for NSAID-related ulcer complication are high age, male sex, ulcer history, and dyspepsia related to the NSAID therapy. Avoiding NSAID therapy in these high-risk patients, whenever possible, might prevent many adverse events. 相似文献
992.
A Abson NJ Broom PA Coates JS Elder AK Forrest PC Hannan AJ Hicks PJ O'Hanlon ND Masson ND Pearson JE Pons JM Wilson 《Canadian Metallurgical Quarterly》1996,49(4):390-394
The synthesis, antibacterial activities, murine pharmacokinetic and infection model data for a range of aryl and heteroaryl ketone derivatives of monic acid (2a) are reported. The best results were found for the 3-furyl and 2-methoxy thiazol-5-yl analogues. 相似文献
993.
The use of hyaluronidase facilitates reduction of paraphimosis. It acts by dispersing extracellular edema, permitting easy reduction of the foreskin. Its use is applicable both in the hospital and outpatient setting. Hyaluronidase is widely available and keeps well if refrigerated. It is effective for children and adults. 相似文献
994.
995.
Morfouli P. Ghibaudo G. Ouisse T. Vogel E. Hill W. Misra V. McLarty P. Wortman J.J. 《Electron Device Letters, IEEE》1996,17(8):395-397
MOSFET's with ultrathin (5 to 8.5 nm) silicon oxynitride gate film prepared by low-pressure rapid thermal chemical vapor deposition (RTCVD) using SiH4, N2O and NH3 gases, are studied by low-frequency noise measurements (1 Hz up to 5 kHz). The analysis takes into account the correlated mobility fluctuations induced by those of the interfacial oxide charge. The nitrogen concentration, determined from SIMS analysis, varies from 0 to 11% atomic percentage. A comparison of the electrical properties between thermal and silicon oxynitride films is presented. The increasing LF noise signal with nitrogen atomic percentage indicates the presence of a higher density of slow interface traps with increasing nitrogen incorporation. Besides, a higher Coulomb scattering rate due to the nitridation induced interface charge explains reasonably well the degradation of the low field mobility after nitridation 相似文献
996.
997.
LA Doyle W Yang LV Abruzzo T Krogmann Y Gao AK Rishi DD Ross 《Canadian Metallurgical Quarterly》1998,95(26):15665-15670
MCF-7/AdrVp is a multidrug-resistant human breast cancer subline that displays an ATP-dependent reduction in the intracellular accumulation of anthracycline anticancer drugs in the absence of overexpression of known multidrug resistance transporters such as P glycoprotein or the multidrug resistance protein. RNA fingerprinting led to the identification of a 2.4-kb mRNA that is overexpressed in MCF-7/AdrVp cells relative to parental MCF-7 cells. The mRNA encodes a 655-aa [corrected] member of the ATP-binding cassette superfamily of transporters that we term breast cancer resistance protein (BCRP). Enforced expression of the full-length BCRP cDNA in MCF-7 breast cancer cells confers resistance to mitoxantrone, doxorubicin, and daunorubicin, reduces daunorubicin accumulation and retention, and causes an ATP-dependent enhancement of the efflux of rhodamine 123 in the cloned transfected cells. BCRP is a xenobiotic transporter that appears to play a major role in the multidrug resistance phenotype of MCF-7/AdrVp human breast cancer cells. 相似文献
998.
SH Opdal TO Rognum A Vege AK Stave BM Dupuy T Egeland 《Canadian Metallurgical Quarterly》1998,87(10):1039-1044
The purpose of the present study was to investigate substitutions in the D-loop of mitochondrial DNA (mtDNA) in sudden infant death syndrome (SIDS) and controls, since several observations indicate the involvement of mtDNA mutations in SIDS. These include elevated levels of vitreous humour hypoxanthine in SIDS victims, familial clustering without mendelian traits, and observations of increased sleepiness and a lower activity score in infants who later succumbed to SIDS. Eighty-two cases of SIDS and 133 controls were investigated and the D-loop sequences were recorded in the base-pair range 16055-16500 in the mtDNA sequence. The sequencing was carried out using the Applied Biosystems Sequenase dye terminator method and a ABD373A sequencer. The recorded D-loop sequences were compared with the Cambridge sequence and differences were recorded as substitutions. The SIDS cases had a tendency towards a higher substitution rate in the D-loop than the controls (p = 0.088). This observation makes it interesting to search for deleterious mutations in other locations in the mtDNA. 相似文献
999.
1000.
This paper presents an empirical analysis of the life span of over 180 systems aimed at developing a model for determining
the planning horizon for new software at the business case stage of software acquisition. At this early stage, the firm has
limited knowledge about the project, but must make crucial decisions, such as scope (breadth of requirements), approach (both
insource vs. outsource and custom vs. package) and technology, including fit with standards (adhere to current vs. adopt new
technology). These decisions are associated with different system lifetimes that, in turn, impact both the costs incurred
and benefits received from the system. The failure to explicitly and properly address these differences can lead to the implementation
of systems better left undone or to unintended consequences, such as the Y2K problem. We find that technology and approach,
but not scope decisions are strongly related to system lifetime. In particular, systems that use an operating system that
conforms to the firm’s standard or are acquired using a blended team entail longer system life. On the other hand, shorter
system life is indicated if the system is technically complex, custom developed or uses an older programming language. Furthermore,
modified packaged software is shorter lived than is a vanilla package. In addition, environmental variables also impact the
appropriate horizon. For example, as one would expect, strategic systems are used longer. On the other hand, somewhat surprisingly,
systems sponsored by executives last less long and despite the quickening pace of technological and business process advancement,
a small trend toward longer lived systems is uncovered. 相似文献