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991.
W Oh DK Stevenson JE Tyson BH Morris CE Ahlfors G Jesse Bender RJ Wong R Perritt BR Vohr KP Van Meurs HJ Vreman A Das DL Phelps T Michael O’Shea RD Higgins 《Acta paediatrica (Oslo, Norway : 1992)》2010,99(5):673-678
Objectives: To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants. Method: Total plasma bilirubin and unbound bilirubin were measured in 1101 extremely low birth weight infants at 5 ± 1 days of age. Clinical criteria were used to classify infants as clinically stable or unstable. Survivors were examined at 18–22 months corrected age by certified examiners. Outcome variables were death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death prior to follow‐up. For all outcomes, the interaction between bilirubin variables and clinical status was assessed in logistic regression analyses adjusted for multiple risk factors. Results: Regardless of clinical status, an increasing level of unbound bilirubin was associated with higher rates of death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss and death before follow‐up. Total plasma bilirubin values were directly associated with death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death before follow‐up in unstable infants, but not in stable infants. An inverse association between total plasma bilirubin and death or cerebral palsy was found in stable infants. Conclusions: In extremely low birth weight infants, clinical status at 5 days of age affects the association between total plasma bilirubin and death or adverse neurodevelopmental outcomes at 18–22 months of corrected age. An increasing level of UB is associated a higher risk of death or adverse neurodevelopmental outcomes regardless of clinical status. Increasing levels of total plasma bilirubin are directly associated with increasing risk of death or adverse neurodevelopmental outcomes in unstable, but not in stable infants. 相似文献
992.
双能量X线骨质密度测量仪监测小儿下肢骨延长骨矿物质的变化 总被引:1,自引:0,他引:1
目的 在儿童骨延长的患儿中 ,为了能够有效地控制骨延长的速率 ,达到骨延长的目的 ,采用双能量X线骨质密度测量仪 (dualenergyX Rayabsorptiometry ,DEXA)监测延长断端骨矿含量 (bonemineralcontent,BMC)的变化。方法 30例患儿中有 5 0处下肢作了骨延长术 ,平均年龄10 .9岁 (5~ 17岁 ) ,引起短肢的病因不同。术后 7~ 10d开始行骨延长 ,每次延长 0 .2 5mm ,每天 4次。牵引延长期间每周扫描一次 ,拆除外固定器后每 2周扫描一次到术后 2年。DEXA扫描的分辨率是 1mm× 1mm ,扫描速度 30mm/s。比较不同延长时期中骨矿含量的变化。分析不同病因和不同外固定器之间骨矿含量变化的差别。结果 不同固定器之间骨矿含量的差别无著性意义。根据骨延长区BMC增加速率 ,将患儿分为快速组、一般组和慢速组。快速组每日BMC增加速率为 0 .3%~ 0 .6 % ,新骨生长快速 ;一般组每日BMC增加 0 .1%~ 0 .3% ,新骨中速生长 ;慢速组每日增加 <0 .1% ,新骨生成缓慢。骨矿化速率与原发病因相关。结论 DEXA能动态监测骨延长中新生骨的骨矿含量的变化 ,根据骨矿含量变化的程度 ,能够调整骨延长的速率 ,从而达到预期骨延长的目的。 相似文献
993.
994.
Jai-Young Lee Kui-Jae Lee Sun Young Youm Mi-Ran Lee Seralathan Kamala-Kannan Byung-Taek Oh 《Bulletin of environmental contamination and toxicology》2010,84(2):250-254
The Permeable Reactive Barriers (PRBs) are relatively simple, promising technology for groundwater remediation. A PRBs consisting of two reactive barriers (zero valent iron-barrier and bio-barrier) were designed to evaluate the application and feasibility of the barriers for the removal of wide range of pollutants from synthetic water. After 470 days of Multi-PRBs column operation, the pH level in the water sample is increased from 4 to 7, whereas the oxidation reduction potential (ORP) is decreased to −180 mV. Trichloroethylene (TCE), heavy metals, and nitrate were completely removed in the zero valent iron-barrier. Ammonium produced during nitrate reduction is removed in the biologically reactive zone of the column. The results of the present study suggest that Multi-PRBs system is an effective alternate method to confine wide range of pollutants from contaminated groundwater. 相似文献
995.
Richard Rauck D. Alexander Oh Neha Parikh Christian Koch Neil Singla Jin Yu 《Current medical research and opinion》2017,33(11):1915-1920
Objective: Fentanyl sublingual spray offers rapid pain relief in opioid-tolerant cancer patients, and may be useful in acute or post-operative pain. Both opioid-naïve and non-tolerant patients are likely to receive opioids in these settings. Understanding the relationship between systemic exposure of fentanyl sublingual spray and effects on respiratory function in opioid-naïve or non-tolerant populations is important to ensure patient safety. This study evaluated single-dose fentanyl sublingual spray in opioid-naïve participants.Research design: Participants were randomized to receive single-dose fentanyl sublingual spray (100, 200, 400, 600, 800?mcg) or fentanyl citrate IV in one of five cohorts. Dosing occurred following a 10-h fast, with fasting continuing for 4?h post-dose. Dose proportionality was assessed using analysis of variance and linear regression techniques. PK assessments and safety monitoring were performed through 24?h post-dose. Safety assessments, including adverse event (AE) monitoring, occurred from dosing through Day 7.Results: Fifty participants (19?53 years) received fentanyl sublingual spray or fentanyl citrate IV. Mean maximum plasma concentrations were reached between 0.27–0.60?h post-dose for fentanyl sublingual spray. Peak (Cmax) and total (AUC0–t, AUC0–∞) fentanyl exposures increased in a linear, but more than dose-proportional manner, with higher doses. The most common AEs were somnolence, nausea, and vomiting. All AEs were mild or moderate in severity. Doses at 400, 600, and 800?mcg were associated with nausea and vomiting, requiring pharmacologic intervention. Hypoxia episodes requiring nasal cannula oxygenation were observed with 600mcg and 800mcg doses.Conclusions: Overall, single-dose fentanyl sublingual spray (100–800?mcg) was generally well tolerated, with greater incidences of AEs (e.g. nausea, vomiting, hypoxia) at higher doses. Doses up to 200?mcg may be safely administered to healthy opioid-naïve individuals with routine monitoring; doses between 400–800?mcg may be administered in settings with nasal cannula oxygenation. 相似文献
996.
Prenylated flavonoids isolated from Erythrina senegalensis were evaluated for their ability to inhibit PLCgamma1 activity in vitro and the formation of inositol phosphates (IPt) in PLCgamma1-overexpressing NIH3T3 fibroblast cells (NIH3T3gamma1 cells). These flavonoids inhibited PLCgamma1 activity in a dose-dependent manner (IC (50) values ranged from 1.0 microg/mL to 35.0 microg/mL) with the exception of alpinumisoflavone ( 5). Also erysenegalensein D ( 2) and erysenegalensein N ( 3) showed inhibition of inositol phosphate formation in NIH3T3gamma1 cells with IC (50) values of 13.0 microg/mL and 10 microg/mL, respectively. Analyzing the relation of structure to activity, the number of prenyl groups and the hydroxylation of the prenyl groups were important factors for the inhibition of PLCgamma1 activity and of inositol phosphate formation. 相似文献
997.
Drug release from the enzyme-degradable and pH-sensitive hydrogel composed of glycidyl methacrylate dextran and poly(acrylic acid) 总被引:2,自引:0,他引:2
Hydrogels composed of glycidyl methacrylate dextran (GMD) and poly(acrylic acid, PAA) were prepared by UV irradiation method for colon-specific drug delivery. GMD was synthesized by coupling of glycidyl methacrylate to dextran in the presence of 4-(N,N-dimethylamino)pyridine. GMD was photo-polymerized by ammonium peroxydisulfate as initiating system in phosphate-buffered solution (0.1 M, pH 7.4). And then, acrylic acid monomer was added and subsequently heat-polymerized by 2,2'-azobisisobutyronitrile as an initiator. The hydrogels exhibited high swelling ratio (about 20) at 37 degrees C, and showed a pH-dependent swelling behavior. In addition, the swelling ratio of the hydrogel was remarkably enhanced to about 45 times in the presence of dextranase at pH 7.4. The swelling-deswelling behavior proceeded reversibly for the GMD/PAA hydrogels between pH 2 and pH 7.4. Release of 5-aminosalicylic acid from the GMD/PAA hydrogels was evaluated in simulated gastrointestinal pH fluids in the absence or presence of dextranase. We concluded that the hydrogels prepared could be used as a dual-sensitive drug carrier for sequential release in gastrointestinal tract. 相似文献
998.
Sang-Chul Shin Hee-Jung Kim In-Joon Oh Cheong-Weon Cho Kyu-Ho Yang 《European journal of pharmaceutics and biopharmaceutics》2005,60(1):67-71
To develop the new gel formulations that show sustained release for a period of time, the bioadhesive carbopol gels containing tretinoin were prepared. The release characteristics of drug from the carbopol gel were studied according to temperature, receptor medium and drug concentration. For the enhancement of its percutaneous absorption, some kinds of penetration enhancer were used. As the concentration of drug increased, the release of drug from the gel increased, showing concentration dependency. The increase of temperature showed the increased drug release, depending on the activation energy of permeation. Among the enhancers used such as the glycols and the non-ionic surfactants, polyoxyethylene 2-oleyl ether showed the best enhancing effect. The carbopol gels of tretinoin containing an enhancer could be developed for the enhanced transdermal delivery of drug. 相似文献
999.
1000.