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51.
Noninvasive monitoring of murine tumor blood flow during and after photodynamic therapy provides early assessment of therapeutic efficacy. 总被引:1,自引:0,他引:1
Guoqiang Yu Turgut Durduran Chao Zhou Hsing-Wen Wang Mary E Putt H Mark Saunders Chandra M Sehgal Eli Glatstein Arjun G Yodh Theresa M Busch 《Clinical cancer research》2005,11(9):3543-3552
PURPOSE: To monitor tumor blood flow noninvasively during photodynamic therapy (PDT) and to correlate flow responses with therapeutic efficacy. EXPERIMENTAL DESIGN: Diffuse correlation spectroscopy (DCS) was used to measure blood flow continuously in radiation-induced fibrosarcoma murine tumors during Photofrin (5 mg/kg)/PDT (75 mW/cm2, 135 J/cm2). Relative blood flow (rBF; i.e., normalized to preillumination values) was compared with tumor perfusion as determined by power Doppler ultrasound and was correlated with treatment durability, defined as the time of tumor growth to a volume of 400 mm3. Broadband diffuse reflectance spectroscopy concurrently quantified tumor hemoglobin oxygen saturation (SO2). RESULTS: DCS and power Doppler ultrasound measured similar flow decreases in animals treated with identical protocols. DCS measurement of rBF during PDT revealed a series of PDT-induced peaks and declines dominated by an initial steep increase (average +/- SE: 168.1 +/- 39.5%) and subsequent decrease (59.2 +/- 29.1%). The duration (interval time; range, 2.2-15.6 minutes) and slope (flow reduction rate; range, 4.4 -45.8% minute(-1)) of the decrease correlated significantly (P = 0.0001 and 0.0002, r2= 0.79 and 0.67, respectively) with treatment durability. A positive, significant (P = 0.016, r2= 0.50) association between interval time and time-to-400 mm3 was also detected in animals with depressed pre-PDT blood flow due to hydralazine administration. At 3 hours after PDT, rBF and SO2 were predictive (P < or = 0.015) of treatment durability. CONCLUSION: These data suggest a role for DCS in real-time monitoring of PDT vascular response as an indicator of treatment efficacy. 相似文献
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To understand antioxidant activity and the role played by melatonin, we have designed and tested several new compounds. We
present the results in terms of structure-activity relationships, focusing on the lack of the methoxy group and the influence
of the amide side chain. Antioxidant activity of melatonin and some new melatonin analogue indole derivatives were investigated,
using lipid peroxidation and superoxide anion radical scavenger activity assays, in rat liver tissue homogenate. Most of the
compounds were found to be very potent inhibitors of malondialdehyde (MDA) formation at 10−3M. Inhibition rates ranged from 75-44 %. However, no significant inhibitory effect was obtained on superoxide anion formation.
Consequently, it can be concluded that these compounds exhibit important LP activity compared to melatonin. 相似文献
53.
Suleyman Ercan M.D. Gokhan Gokaslan M.D. Vedat Davutoglu M.D. Ibrahim Halil Inanc M.D. Vuslat Bosnak M.D. Hayati Deniz M.D. 《Echocardiography (Mount Kisco, N.Y.)》2013,30(8):E236-E238
Herein, we present a case of asymptomatic isolated cardiac cystic echinococcosis localized entirely to the inter‐atrial septum in a pregnant woman. The patient underwent successful surgery. Cardiac cystic echinococcosis is rarely seen in pregnancy. A high index of suspicion is necessary for the diagnosis of a cardiac cyst hydatid. The treatment of cardiac cyst hydatid is surgical and should not be delayed during pregnancy. Early surgery might prevent septic embolization and cardiac life‐threatening complications and save the lives of both mother and baby as in the present case. 相似文献
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Tanıl Kendirli Aysun Çaltık Murat Duman Hayri Levent Yılmaz Dinçer Yıldızdaş Mehmet Boşnak Deniz Tekin Nilgün Atay 《Pediatrics international》2011,53(1):94-99
Background: The Pediatric Advanced Life Support Program (PALS) course very important for teaching about intubation, resuscitation, shock, trauma, respiratory failure and rhythm disturbances. The aim of the present study was to evaluate the effect of the PALS course on pediatric residents' intubation success during their rotation, daytime and night‐time practice in the pediatric intensive care unit (PICU). Methods: The study was carried out from 1 March 2005 to 28 February 2007. The study period had two parts, in that the number of attempts and successful intubations performed by pediatric residents, and the pediatric intensivist successful intubation ratio were evaluated in two different periods: before the PALS course, 1 March 2005–28 February 2006, and after the PALS course, 5 March 2006–28 February 2007. The participating residents' pediatric levels (PL) were classed as PL‐1, PL‐2, PL‐3, PL‐4, and all had first experience in the PICU at the PL‐1 level. The PALS instructor was a pediatric emergency or intensive care doctor. We evaluated whether the PALS course influenced intubation success or not. Results: Sixteen residents participated in the study. The proportion of successful intubations was 110 (53.3%) and 104 (65.4%) attempts before and after the PALS course, respectively. The proportion of intubations done by intensivists decreased from 49.1% to 31.7% before and after PALS. The most frequently used endotracheal tube (ETT) internal diameter (ID) was 4.0 mm, and cuffed ETT was used 16% and 21% before and after the course, respectively. Appropriate placing of ETT tip occurred 70.4% and 82.2% of the time before and after the PALS course, respectively. Proportion of successful intubations by residents increased in all levels, except for PL‐1. The most important reason for unsuccessful attempts was inappropriate patient position. Only one patient could not be intubated, and laryngeal mask airway was used in that case. During intubation, complications were broken teeth in two patients before the course, and subglottic stenosis developed in only one patient due to cuffed ETT. Conclusion: Successful intubation is a life‐saving intervention during resuscitation, ETT revision for extubation or obstruction for extubation or obstruction during mechanical ventilation. This skill can be developed in the PALS course and by clinical study in PICU and pediatric emergency services. The PALS course must be given to pediatric residents especially within the first year. Also, cuffed ETT can be used for infants and children. 相似文献
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