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EDWARD HURVITZ 《Developmental medicine and child neurology》2009,51(11):847-848
3.
CLOSED CHAMBER SYSTEM FOR DELIVERY OF ETHANOL TO CELL CULTURES 总被引:3,自引:0,他引:3
ADICKES EDWARD D.; MOLLNER TERESA J.; LOCKWOOD SUSAN K. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1988,23(5):377-381
The accuracy and consistency of the delivery of ethanol to culturedcells is important to determine effects on morphologic, biochemicaland physiologic alterations. Open and closed chamber systemswere evaluated to determine cytotoxic vs sublethal, potentiallyteratogenic effects on neonatal rat cardiac myocytes. The open system employed a variety of cell culture vessels.Cardiac cells were exposed directly to ethanol in the growthmedia at concentrations of 550 mM in Petri dishes, multiwellslides and multiwell chambers. Ethanol concentrations in themedia in these open vessels decreased over 60% in a 24 hr incubationperiod. A closed system consisted of tightly sealed plastic containersin which the same vessels were used. The vessels were placedon a platform over a bath of ethanol-water. Cells were acclimatedfor 24 hr with ethanol in the bath at 200% of the final desiredmedia concentration. Ethanol gradually diffused into the mediato reach peak levels of 5, 10,25 or 50 mM at 24 hr. After the24 hr period, ethanol was added to both the media and bath atthe desired concentration. Cells exposed gradually to ethanol in the closed chambers remainedviable, but showed slower division and growth. A period of gradualacclimation is required to induce sublethal cellular effectsrather than lethal effects. The diversity of cell systems andmanipulations of cultures to study the potential teratogeniceffects of ethanol are improved using such a closed chambersystem. 相似文献
4.
Chronic renal failure: factors influencing nephrology referral 总被引:10,自引:2,他引:8
KHAN I.H.; CATTO G.R.D.; EDWARD N.; MACLEOD A.M. 《QJM : monthly journal of the Association of Physicians》1994,87(9):559-564
Factors influencing referral of all 304 patients who developedpersistent renal failure during one year were studied in thestable Grampian population. The annual incidence of chronicrenal failure (CRF) (creatinine 相似文献
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EDWARD VICTOR ROSS MD NATHAN S. UEBELHOER DO YACOV DOMANKEVITZ PHD 《Dermatologic surgery》2007,33(12):1466-1469
BACKGROUND Purpura-free elimination of telangiectases with a single pass of a pulsed dye laser with a large spot has proved difficult.
OBJECTIVE The purpose of this report was to define parameters that achieve single-pass purpura-free telangiectasia reduction.
MATERIALS Thirty patients between the ages of 23 and 78 years were treated with a pulsed dye laser with a 10-mm spot and fluences ranging from 9 to 10 J/cm2 . The macropulse width was 20 ms. Each macropulse was composed of eight pulselets. Treatments were carried out over facial areas with discrete telangiectases.
RESULTS Smaller telangiectases (<600 μm) showed transient bluing followed by stenosis. Larger vessels (600–10,000 μm) showed bluing but inconsistent closure. A second pass typically resulted in closure.
CONCLUSION A modified pulsed dye laser was capable of single-pass purpura-free reduction with a 10-mm spot size. 相似文献
OBJECTIVE The purpose of this report was to define parameters that achieve single-pass purpura-free telangiectasia reduction.
MATERIALS Thirty patients between the ages of 23 and 78 years were treated with a pulsed dye laser with a 10-mm spot and fluences ranging from 9 to 10 J/cm
RESULTS Smaller telangiectases (<600 μm) showed transient bluing followed by stenosis. Larger vessels (600–10,000 μm) showed bluing but inconsistent closure. A second pass typically resulted in closure.
CONCLUSION A modified pulsed dye laser was capable of single-pass purpura-free reduction with a 10-mm spot size. 相似文献
7.
J. DAVID TALLEY M.D. FAYAZ SHAWL M.D. AUGUSTO PICHARD M.D. ALLESANDRO GIAMBARTOLOMEI M.D. PAUL OVERLIE M.D. ROBERT SIEGEL M.D. JOEL ROSENBERG M.D. CHRISTOPHER U. CATES M.D. FRANK CUMMINS M.D. EDWARD KOSINSKI M.D. 《Journal of interventional cardiology》1997,10(4):295-299
Lesions in the distal portion of coronary arteries are technological challenges with currently available percutaneous transluminal coronary angioplasty (PTCA) equipment. A study was performed at multiple centers to determine if new "fixed-wire" devices with a modified distal tip (a 2-cm flexible tip and 1-cm standard tip) would be useful in these situations. Three hundred twenty-three patients were included in the study, 75% male, mean age 63 ± 11 years. Four hundred ninety-three lesions were attempted; the overall success rate was 85%. Forty-six (14.2%) clinical complications occurred including: 5 deaths (1.1%); 2 nonfatal myocardial infarctions (0.6%); and 6 emergency coronary artery bypass grafting procedures (2.6%). A device malfunction was noted in 32 patients (9.9%), and included: 8 balloon ruptures or perforations (2.0%); 6 bent or damaged tips (1.9%); and 4 shaft/manifold leaks (1.2%). Two-month follow-up assessment for restenosis was done in 352 of 371 (95%) patients and at that time 89% were asymptomatic, had a negative functional test, or patent PTCA site by angiography. The new fixed-wire PTCA catheters with 1- and 2-cm flexible tips hold promise for dilating lesions in distal locations with an acceptable rate of complications. Additional investigation is needed to determine their role in the treatment of coronary artery disease with PTCA. 相似文献
8.
This experiment tested the hypothesis that inotropic cardiovascular reactivity to stress is related to performance on heartbeat discrimination tasks. The experiment also compared the efficacy of a specific modification of two popular heartbeat discrimination paradigms, Whitehead's and Katkin's. Subjects were 48 male undergraduates who performed both discrimination tasks and then were subjected to mental arithmetic stress. Results indicated that high cardiovascular reactors were better detectors than low reactors. Results also indicated that subjects performed better on the modified Whitehead task than on the modified Katkin task. 相似文献
9.
An Investigation into the Electrical Ablation Technique and a Method of Electrode Assessment 总被引:1,自引:0,他引:1
Ablative techniques, using standard defibrillators and commonly available cardiac catheters, have been applied to the His bundle and bypass tracts for the management of arrhythmias. We have done in vitro studies of the physical effects of these high energy electrical impulses delivered via different pacing electrodes. Unipolar impulses of 10 to 400 joules were delivered via three U.S.C.I. bipolar electrodes and three Vitatron Helifix electrodes immersed in Ringer's solution. The effects were recorded on 35 mm still film, video tape, and high speed cine film. Pressure, voltage, and current were measured. The U.S.C.I. bipolar electrodes and the Vitatron Helifix electrodes safely withstood repeated delivery of 400-joule impulses which produced similar flash shapes. Each took the form of an incandescent, spherical "fire-ball" centered around the exposed electrode surface. The mean diameters of the "fire-ball" for 10 to 400 J using the U.S.C.I. electrodes were 5-24 mm and 3-20 mm for the Helifix catheter electrodes. Peak pressure excursions of over an atmosphere were observed 3 cm from the electrode tips. Higher pressures, lower voltages, and larger currents occurred using the U.S.C.I. pacing lead. The simple, 35 mm time exposure technique showed that at low energies the flashes appeared to emerge in a retrograde manner from the U.S.C.I. catheters and more distally from the Helifix electrode. This suggested that the latter might be more effective with lower energy impulses. It is concluded that lower energies should be used to take full advantage of the active fixation electrode. 相似文献
10.
SOO-KYUNG LEE PhD RD JEFFEREY SOBAL PhD MPH EDWARD A FRONGILLO Jr PhD 《Journal of the American Dietetic Association》1999,99(9):1084-1089
OBJECTIVE: Examine variation in dietary practices and nutritional intakes of Korean Americans at different acculturation levels. DESIGN: Cross-sectional mail survey. SUBJECTS/SETTING: US national sample of 348 Korean Americans (46% of the Korean American sample to whom questionnaires were delivered). STATISTICAL ANALYSIS PERFORMED: Analysis of variance, Pearson correlation, Spearman rank correlation, chi 2 test, and multiple regression analysis. RESULTS: Korean Americans who were more acculturated consumed more American food and less Korean food. American foods such as oranges, low-fat milk, bagels, tomatoes, and bread were consumed regularly by Korean Americans; Korean foods such as rice, kimchi, garlic, green onions, and Korean soup were also consumed regularly. American foods were adopted the most at breakfast and the least at dinner. Bicultural people regularly incorporated more different types of foods into their diet. Despite significant differences in dietary practices, dietary quality did not vary by acculturation status. APPLICATION/CONCLUSIONS: Acculturation was influential in the dietary patterns of Korean Americans. Specific information about Korean diet related to acculturation status can be used by dietitians who work with Korean Americans. Dietitians can benefit from gathering and applying specific information about Korean diets and diets of other ethnic groups; they also need to recognize the changing nature of dietary patterns as acculturation occurs. 相似文献