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1.
This paper investigates the quantized sliding mode control of Markov jump systems with time‐varying delay. A dynamical adjustment law is explored to quantize the system output. By constructing an observer‐based integral sliding surface, a sliding mode controller is designed to take over the dynamical motion of state estimation and ensure the reachability of sliding surface. A new scaling manner is developed to build the bound between the system output and quantized error. With the help of separation strategies for controller synthesis and general transition probabilities and a lower bound theorem for nonlinear integral terms, a new synthesis method to ensure the required stability and meet the required performance is proposed in the form of linear matrix inequalities. The validity of the proposed control method is illustrated by a numerical example. 相似文献
2.
3.
《Drug metabolism and pharmacokinetics》2019,34(5):308-316
LC-MS quantification of drug metabolites is sometimes impeded by the availability of internal standards that often requires customized synthesis and/or extensive purification. Although isotopically labeled internal standards are considered ideal for LC-MS/MS based quantification, de novo synthesis using costly isotope-enriched starting materials makes it impractical for early stage of drug discovery. Therefore, quick access to these isotope-enriched compounds without chemical derivatization and purification will greatly facilitate LC-MS/MS based quantification. Herein, we report a novel 18O-labeling technique using metabolizing enzyme carboxylesterase (CES) and its potential application in metabolites quantification study. Substrates of CES typically undergo a two-step oxygen exchange with H218O in the presence of the enzyme, generating singly- and doubly-18O-labeled carboxylic acids; however, unexpected hydrolytic behavior was observed for three of the test compounds – indomethacin, piperacillin and clopidogrel. These unusual observations led to the discovery of several novel hydrolytic mechanisms. Finally, when used as internal standard for LC-MS/MS based quantification, these in situ labeled compounds generated accurate quantitation comparable to the conventional standard curve method. The preliminary results suggest that this method has potential to eliminate laborious chemical synthesis of isotope-labeled internal standards for carboxylic acid-containing compounds, and can be developed to facilitate quantitative analysis in early-stage drug discovery. 相似文献
4.
目的探讨评教评学模式在肿瘤外科护理带教中的应用效果。方法选择2017年6月—2019年2月于该院肿瘤外科实习的88名护生作为该次研究对象,随机将护生分为对照组与观察组,两组分别有护生44名,对照组给予传统带教方法,观察组给予评教评学模式带教,比较两组护生的护理带教结果。结果观察组护生对带教老师综合能力评价优良率是92.0%,对照组评价优良率是76.0%,组间对比差异有统计学意义(χ^2=4.192,P=0.041<0.05)。观察组带教老师对护生综合能力评价优良率是90.9%,对照组评价优良率是72.7%,组间对比差异有统计学意义(χ^2=4.889,P=0.027<0.05)。观察组护生的理论知识与实操技能考核成绩均要显著比对照组高,差异有统计学意义(P<0.05)。结论评教评学模式在肿瘤外科护理带教中具有显著应用价值,可充分激发师生的教学积极性,改善护理教学质量。 相似文献
5.
D. Sforza G. Iaria L. Petagna A. Parente A. Anselmo F. Sergi S. Marzio F. Corrado S. Telli T.M. Manzia G. Tisone 《Transplantation proceedings》2019,51(1):140-142
Background
One daily dose of tacrolimus (QDT) improves adherence in kidney transplant (KT) recipients. A switch from twice-daily tacrolimus (BDT) to QDT showed similar efficacy and safety.Methods
The aim of our study was to demonstrate the long-term efficacy and safety of switching from BDT to QDT in KT recipients. Preliminary results have already been published. Forty-one patients (34 men and 7 women), mean age at KT of 43.9 ± 12.7 years, underwent a 1:1 dose switch from BDT to QDT; the mean time from KT to switch was 36.6 ± 16.1 months. In our study population, 4 patients received a living donor KT and 2 received a second allograft.Results
The mean follow-up was 86.8 ± 13 months from the switch and 126.2 ± 22.3 months from KT. Graft and patient survival rates were 90.2% and 95.1%, respectively. All patients maintained stable renal function during follow-up. During the first 3 months after the switch we observed a significant decrease in tacrolimus blood level (P = .0001). No significant differences were observed regarding tacrolimus dose before and after QDT introduction (P = not significant [NS]). Fourteen patients who stopped steroids under BDT treatment and 16 patients who stopped steroids after the switch are currently steroid-free.Conclusion
Our study showed safety and efficacy in switching from BDT to QDT. After early (<1 year) dose adjustment, tacrolimus blood levels remained stable throughout follow-up. Moreover, QDT represented a valid alternative for patients showing steroid side effects. 相似文献6.
K. Reynen U. Röber W.G. Daniel R. Henßge S. Schüler 《Clinical research in cardiology》1998,87(5):331-335
Zusammenfassung Zahlen zur H?ufigkeit von Herztumoren im operativen Krankengut liegen bisher für die Bundesrepublik Deutschland nicht vor.
Um einen entsprechenden überblick für das Jahr 1996 zu erhalten, wurde allen 77 herzchirurgischen Zentren der Bundesrepublik
Deutschland ein standardisierter Fragebogen zugesandt.
Daten von 65 der 77 Herzzentren (=84%) waren schlie?lich verfügbar: 187 Patienten waren wegen Myxomen, lediglich 44 wegen
nichtmyxomat?sen Tumoren, davon 28 wegen malignen prim?ren oder sekund?ren Herztumoren, operiert worden. Im Jahr 1996 waren
somit 0,32% (231/72 763) der Eingriffe mit Herz-Lungen-Maschine (erfa?t 72 763 von insgesamt 87 372) wegen eines Herztumors
vorgenommen worden. Ausgehend von diesen operativen Daten liegt die Inzidenz ausschlie?lich der prim?ren Tumoren des Herzens
zumindest bei 3 Tumoren pro 1 Million Einwohner pro Jahr (253 Tumoren/81,814 Millionen Einwohner). Wenn auch kleine Tumoren
asymptomatisch und unentdeckt bleiben k?nnen, wird heute doch die Mehrzahl prim?rer kardialer Tumoren durch Echokardiographie,
Computer- und Kernspintomographie bereits zu Lebzeiten des Patienten diagnostiziert, und diese Patienten werden in aller Regel
einer Operation zugeführt.
Somit werden gut 0,3% aller Eingriffe mit Herz-Lungen-Maschine in Deutschland wegen Herztumoren durchgeführt, wobei es sich
weit überwiegend um Myxome handelt.
Eingegangen: 23. September 1997, Akzeptiert: 11. Februar 1998 相似文献
7.
Wolfgang Söllner Gerlinde Mairinger Martina Zingg-Schir Peter Fritsch 《Der Hautarzt; Zeitschrift für Dermatologie, Venerologie, und verwandte Gebiete》1996,47(3):200-205
Zusammenfassung
Bei 205 Melanompatienten im Stadium I und II wurden das Ausma? der psychosozialen Belastung und der sozialen Unterstützung
sowie die Einstellung der Patienten zu unterstützenden Gespr?chsangeboten erhoben. 59% der Patienten fanden zus?tzliche unterstützende
Gespr?che mit dem behandelnden Dermatologen, 20% mit einem Psychotherapeuten sinnvoll. Patienten, die starke Angst vor einem
Fortschreiten des Tumors ?u?erten und die sich über die Erkrankung nicht ausreichend aufgekl?rt fühlten, wünschten Gespr?che
mit dem behandelnden Arzt. Patienten, die sich psychosozial st?rker belastet fühlten und sozial weniger Unterstützung durch
ihr soziales Umfeld angaben, befürworteten Unterstützung durch einen Psychotherapeuten. Auch eine ungünstige Prognose scheint
das Interesse an psychotherapeutischer Unterstützung zu verst?rken.
Eingegangen am 13. Januar 1995 Angenommen am 23. August 1995 相似文献
8.
Detection of Atrial Fibrillation by Implanted Devices with Wireless Data Transmission Capability 总被引:3,自引:0,他引:3
NIRAJ VARMA† BRUCE STAMBLER SUNG CHUN† 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S133-S136
Remote telemetry may facilitate the management of implantable devices. We tested the reliability of a new automatic, wireless home monitoring (HM) system that archives data every 24 hours. We retrospectively analyzed archival data from 276 consecutive pacing system implants to define temporal atrial fibrillation (AF) patterns and associated ventricular rate. An "AF day" was defined by a >20%/24 hour mode switch (MS) duration, irrespective of the MS number. Management decisions resulting from transmissions were noted. A pilot study confirmed that 89% of 22,356 transmissions were successful, of which >90% were received in <5 minutes. Data integrity was 100% preserved. Overall, AF developed in 29 patients (10.5%), representing a total of 645 AF days (mean = 22.2 ± 29.6 AF, median = 9 days), over 12 ± 2 months of monitoring. AF was infrequent (50% of 24 hours. Ventricular rates during 645 AF days in 29 patients averaged 95.1 ± 9.9 beats/min (median = 94 beats/min). Ventricular rates were >80 beats/min in 25 ± 30 AF days (median = 11 days). HM enabled rapid anticoagulation decisions. In recipients of implantable devices, automatic wireless telemetry with HM was efficient and reliable. Its application may overcome some current challenges in AF management by early notification and precise measurement of both AF burden and ventricular rate during AF. 相似文献
9.
10.
I was honored to study the undergraduate course in Hong Kong Polytechnic University for 4 months in 2006, experienced the characteristic and teaching mode of Hong Kong nursing education on undergraduate course personally. Make an introduction from respects such as course offered, teaching method, educational idea, examination way, etc. now, and compare with domestic nursing education. 相似文献