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1.
A Serrano Pascual C Merino Hernáez R Ochoa Mejías A Escolano Chamois J Golbano Ablanque I Otero Tejero M Sanz Redondo F Román Ruiz 《Canadian Metallurgical Quarterly》1997,21(6):631-635
BACKGROUND AND AIMS OF THE STUDY: Surgical treatment of functional tricuspid regurgitation associated with advanced valvular disease remains controversial, mainly due to the difficulty in choosing between valve replacement or reconstructive surgery. Failure to correct tricuspid regurgitation during valvular surgery carries a poor prognosis, as reoperation may represent a significant risk to the patient. Thus correct tricuspid valve surgery is vital to achieve improved early and long-term clinical results. METHODS: A total of 142 patients underwent concomitant tricuspid annuloplasty with mitral valve replacement and their clinical outcome was assessed. RESULTS: Overall hospital mortality rate was 11.3%. Seven patients died during follow up. The overall actuarial survival rate for 10 years was 74.1 +/- 14.2%. Postoperatively, 75.8% of the patients had no residual tricuspid insufficiency, while 24.2% had first- or second-degree tricuspid insufficiency and were treated medically. All patients were in NHYA functional class I or II postoperatively. CONCLUSION: Clinically, it is important to assess the severity of functional tricuspid insufficiency before and/or during the operation. Bicuspidalization annuloplasty for functional tricuspid insufficiency has provided good results, with a low incidence of reoperation and significant clinical improvement. The technique could be used in most patients with functional tricuspid regurgitation. 相似文献
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The therapeutic panorama of immunomodulation and its effects on the modification of the immune reaction is reviewed. Particular reference is made to the transfer factor as a therapeutic element in bronchial asthma, which insures its efficacy or innocuity. 相似文献
3.
DiPietro Janet A.; Caulfield Laura; Costigan Kathleen A.; Merialdi Mario; Nguyen Ruby H. N.; Zavaleta Nelly; Gurewitsch Edith D. 《Canadian Metallurgical Quarterly》2004,40(3):445
Longitudinal neurobehavioral development was examined in 237 fetuses of low-risk pregnancies from 2 distinct populations-Baltimore, Maryland, and Lima. Peru-at 20. 24. 28. 32, 36. and 38 weeks gestation. Data were based on digitized Doppler-based fetal heart rate (FHR) and fetal movement (FM). In both groups. FHR declined while variability, episodic accelerations, and FM-FHR coupling increased, with discontinuities evident between 28 and 32 weeks gestation. Fetuses in Lima had higher FHR and lower variability, accelerations, and FM-FHR coupling. Declines in trajectories were typically observed 1 month sooner in Lima, which magnified these disparities. Motor activity differences were less consistent. No sex differences in fetal neurobehaviors were detected. It is concluded that population factors can influence the developmental niche of the fetus. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Rajendran Mala Antony Annie Aglin Arul Selvaraj Ruby Celsia Sivalingam Geerthika Narbahvi Kiruthika Chinnathambi VazagaPriya Kumarapillai Srinivasa Kumar 《IET nanobiotechnology / IET》2017,11(5):612
Foley catheters are inevitable in health care unit. Pathogens colonise and form biofilm on catheter causing catheter‐associated urinary tract infection. Therefore, the authors aimed to functionalise catheter to resist biofilm formation. The authors impregnated urinary catheters with a synergistic combination of antibiotics and silver nanoparticles (SNPs) to evaluate antibiofilm efficacy in vitro and in vivo. SNPs were synthesised using Spirulina platensis. Synergy between the SNPs and antibiotics was determined by the checker‐board method. In vivo efficacy of the functionalised catheters was assessed in mice. Liver and kidney function tests of mice were performed. The in vitro anti‐adherence activity of the functionalised catheters was evaluated after 2 years. Nanoparticle sizes were 42–75 nm. Synergistic activity was observed among SNPs (2 µg/ml), amikacin (6.25 µg/ml), and nitrofurantoin (31.25 µg/ml). In mice, catheters functionalised with combinations of antibiotics and SNPs exhibited no colonisation until Day 14. Blood, liver, and kidney tests were normal. After 2 years, catheters functionalised with antibiotics exhibited 25% inhibition of bacterial adhesion, and catheters functionalised with the nanoparticle‐antibiotic combination exhibited 90% inhibition. Impregnation of urinary catheters with a synergistic combination of antibiotics and SNPs is an efficient and promising method for preventing biofilm formation.Inspec keywords: catheters, drugs, silver, nanoparticles, nanomedicine, liver, kidney, blood, microorganisms, adhesion, biomechanics, cellular biophysicsOther keywords: Foley catheters, synergistic nanoparticle‐antibiotics combination, silver nanoparticles, biofilm formation resitance, health care unit, pathogens, urinary tract infection, SNP, Spirulina platensis, checker‐board method, liver function, kidney function, vitro antiadherence activity, amikacin, nitrofurantoin, blood, bacterial adhesion, size 42 nm to 75 nm, Ag 相似文献
6.
Reliability and time‐to‐failure bounds for discrete‐time constrained Markov jump linear systems 下载免费PDF全文
This paper presents a methodology to obtain a guaranteed‐reliability controller for constrained linear systems, which switch between different modes according to a Markov chain (Markov jump linear systems). Inside the classical maximal robust controllable set, there is 100% guarantee of never violating constraints at future time. However, outside such set, some sequences might make hitting constraints unavoidable for some disturbance realisations. A guaranteed‐reliability controller based on a greedy heuristic approach was proposed in an earlier work for disturbance‐free, robustly stabilisable Markov jump linear systems. Here, extensions are presented by, first, considering bounded disturbances and, second, presenting an iterative algorithm based on dynamic programming. In non‐stabilisable systems, reliability is zero; therefore, prior results cannot be applied; in this case, optimisation of a mean‐time‐to‐failure bound is proposed, via minor algorithm modifications. Optimality can be proved in the disturbance‐free, finitely generated case. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
7.
Polyfunctional macromonomers obtained from 2,2‐bis(hydroxymethyl) propanoic acid and tall oil fatty acids 下载免费PDF全文
Macromonomers (MMs) were obtained with different proportions of dimethylolpropionic acid (DMPA) and tall oil fatty acid (TOFA). The MMs were characterized by their acid value (AV), their hydroxyl value (OHV), IR spectroscopy, NMR, electrospray ionization–mass spectrometry, UV spectroscopy, rheological, differential scanning calorimetry, thermogravimetric analysis, gloss, flexibility, and adherence analyses. The presence of hydroxyl and ester groups and double bonds were confirmed by IR and NMR analyses. IR analysis showed that the intensity of the OH groups decreased with the addition of TOFA. In all cases, the AVs of the MMs were lower than those of DMPA and TOFA. By electrospray ionization–mass spectrometry, the formation of the DMPA homopolymers and structures with molecular weights higher than that of DMPA were observed. All of the MMs were amorphous. The viscosity of the MMs decreased with the addition of TOFA. The gloss values of the MMs at 85° were higher than 100, and the flexibility was good. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42029. 相似文献
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Bolleddula Jayaprakasam Ruby L. Alexander-Lindo David L. DeWitt Muraleedharan G. Nair 《Food chemistry》2007,105(2):485-490
Stinking toe (Hymenaea courbaril), also called Jatoba and Kerosene tree, is a medicinal plant commonly found in the central and South American countries. In the Caribbean, Mexico and Brazil, the powdery sweet dust of its fruit is consumed for energy. The chemical examination of the yellowish sweet powder of the fruit yielded sucrose and linolenic acid as major compounds. The pods yielded the labdane diterpenoids crotomachlin (1), labd-13E-en-8-ol-15-oic acid (2), labdanolic acid (4), (13E)-labda 7, 13 dien-15-oic acid (5) and labd-8 (17), 13E- dien-15-oic acid (6), along with the sesquiterpene, spathulenol (7), as confirmed by 1H and 13C NMR spectral studies. The methyl ester of labd-13E-en-8-ol-15-oic acid (3) was also characterized during the purification of compound 5. The total amount of these terpenoids in the fruit was about 0.1% (w/w) of the dried fruit. Compounds 1–5 and 7 were assayed for anti-inflammatory activity using cyclooxygenase-1 (COX-1) and -2 (COX-2) enzymes. At 100 ppm, compounds 3 and 4 showed selective COX-2 enzyme inhibition. Also, compounds 1, 2 and 5 inhibited lipid peroxidation by 46%, 48% and 75%, respectively, at 100 ppm. These compounds were isolated from this fruit and their COX and lipid peroxidation inhibitory activities are reported for the first time in this paper. 相似文献
10.
Mejía-Centeno Isidro Martínez-Hernández Angel Fuentes Gustavo A. 《Topics in Catalysis》2007,42(1-4):381-385
The use of low-sulfur fuel is known to improve the performance of the three-way catalytic converter (TWC). However, in this
work we report how low-sulfur operation of commercial TWC also favors formation of N2O and NH3 as by products. We found that low-sulfur rich operation above 300 °C increases the production of NH3, inhibiting the formation of N2O characteristic of high-sulfur operation. During lean operation, the production of N2O near the stoichiometric point is not significantly affected by the sulfur level. The large production of N2O observed during light-off is not affected by SO2 when the operation is lean, but under rich conditions N2O is produced up to 575 °C. The increased production of NH3 and N2O in TWC as a result of the introduction of low-sulfur gasoline is an area that requires further analysis because of its implication
upon public health in large urban settings. 相似文献