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991.
Yuang Mao Chang Zhao Shuyan Ge Tao Luo Jie Chen Jiyang Liu Fengna Xi Junjie Liu 《RSC advances》2019,9(57):32977
Sensitive and reliable detection of mercury ions (Hg2+) and l-cysteine (l-Cys) is of great significance for toxicology assessment, environmental protection, food analysis and human health. Herein, we present gram-scale synthesis of nitrogen doped graphene quantum dots (N-GQDs) for sensitive detection of Hg2+ and l-Cys. The N-GQDs are one-step synthesized using bottom-up molecular fusion in a hydrothermal process with gram-scale yield at a single run. N-GQDs exhibit good structural characteristics including uniform size (∼2.1 nm), high crystallinity, and single-layered graphene thickness. Successful doping of N atom enables bright blue fluorescence (absolute photoluminescence quantum yield of 24.8%) and provides unique selectivity towards Hg2+. Based on the fluorescence quenching by Hg2+ (turn-off mode), N-GQDs are able to serve as an effective fluorescent probe for sensitive detection of Hg2+ with low limit of detection (19 nM). As l-Cys could recover the fluorescence of N-GQDs quenched by Hg2+, fluorescent detection of l-Cys is also demonstrated using turn-off-on mode.One-step and gram-scale synthesis of nitrogen doped graphene quantum dots is realized for their sensitive detection of Hg2+ and l-Cys. 相似文献
992.
R. C. Brennan W. Furman S. Mao J. Wu D. C. Turner C. F. Stewart V. Santana L. M. McGregor 《Cancer chemotherapy and pharmacology》2014,74(6):1191-1198
Purpose
This phase I study endeavored to estimate the maximum tolerated dose and describe the dose-limiting toxicities (DLTs) of oral irinotecan with gefitinib in children with refractory solid tumors.Methods
Oral irinotecan was administered on days 1–5 and 8–12 with oral gefitinib (fixed dose, 150 mg/m2/day) on days 1–12 of a 21-day course. The escalation with overdose control method guided irinotecan dose escalation (7 dose levels, range 5–40 mg/m2/day).Results
Sixteen of 19 patients were evaluable, with serial pharmacokinetic studies in ten patients. Diagnoses included osteosarcoma (N = 5), neuroblastoma (N = 3), sarcoma (N = 3), and others (N = 5). Patients received a median of two courses (range 1–20), with at least two patients treated on dose levels 2–7. Three patients had five DLTs; the most common being metabolic (hypokalemia, N = 2 and hypophosphatemia, N = 1) at dose levels two (10 mg/m2) and four (20 mg/m2). One patient experienced grade 3 diarrhea (40 mg/m2). Irinotecan bioavailability was 2.5-fold higher when co-administered with gefitinib, while the conversion rate of irinotecan to SN-38 lactone was unaffected. The study closed due to poor accrual before evaluation of the next recommended irinotecan dose level (35 mg/m2). Of 11 patients receiving at least two courses of therapy, three had stable disease lasting two to four courses and one patient maintained a complete response through 18 courses.Conclusions
The combination of oral gefitinib and irinotecan has acceptable toxicity and anti-tumor activity in pediatric patients with refractory solid tumors. Pharmacokinetic analysis confirms that co-administration of gefitinib increases irinotecan bioavailability leading to an increased SN-38 lactone systemic exposure. 相似文献993.
Chen ML Mao IF Wu MT Chen JR Ho CK Smith TJ Wypij D Christiani DC 《American Industrial Hygiene Association journal》1999,60(1):105-110
Coking workers are regularly exposed to coke oven emissions, which consist primarily of polycyclic aromatic hydrocarbons and volatile organic compounds. This study measured the workers' exposure to the benzene soluble fraction of total particulates (BSF). The study population consisted of 88 coking workers as an exposure group and 59 referents. Personal breathing-zone samples of BSF and total particulates were taken from all study subjects for 3 consecutive days. The highest BSF concentrations were found among the topside oven workers (geometric mean; range) (microgram/m3): lidman (515; 72-18, 181), tar chaser (432; 51-4334), and larry car operator (185; 55-649). The lowest was 7 micrograms/m3 in the referents. Among the samples at the topside oven 84% exceeded the Occupational Safety and Health Administration standard (150 micrograms/m3 BSF). The percentage of BSF in total particulates varied across job classifications, ranging from 0.3% in wharfmen to 24% in tar chasers. Area sampling indicated that the BSF concentration at the topside area was sixtyfold higher than that at the administrative area, which was approximately 2 km from the coke oven plant. 相似文献
994.
The p38 mitogen-activated protein kinase (p38 MAPK) pathway is involved in the osteoclast differentiation. The aim of the study was to investigate whether SB203580, a p38 MAPK inhibitor, inhibits wear-debris-induced inflammatory osteolysis in mice. Forty-five mice were implanted with calvaria bone from syngeneic littermates; then, titanium (Ti) particles were injected into established air pouches to provoke inflammatory osteolysis. At 14?days after bone/Ti implantation, pouch membranes with intact bone implants underwent histological and molecular analysis. SB203580 had less effect on MMP-9 and TNF-?? expression under wear-debris-induced conditions. SB203580, by inhibiting the expression of p38 MAPK and phospho-p38 MAPK, inhibited Ti particle wear-debris-induced inflammatory osteolysis. It also remarkably decreased the number of tartrate-resistant acid phosphatase positive cells in Ti-particle-induced pouch tissues. Results suggest that p38 MAPK may be critical in a murine osteolysis model. SB203580 may notably inhibit wear-debris-induced inflammatory osteolysis by down-regulating expression of MMP-9 and TNF-?? via the p38 MAPK pathway. 相似文献
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目的:观察采用谷氨酰半胱氨酸合成酶抑制剂--丁胱亚磺酰亚胺(BSO)排空大鼠心肌谷胱甘肽(GSH)是否影响大鼠心肌组织GSH的稳态,以及是否对GSH代谢相关酶活性及mRNA表达产生影响.方法:采用长时间力竭运动、注射BSO排空GSH两种实验模型,比较对照组与注射BSO组SD大鼠心肌在静息状态和长时间力竭运动后GSH状态及其代谢变化.结果:注射BSO 8天后,大鼠心脏GSH含量分别为对照组?%,且GSH的下降伴随着氧化型谷胱甘肽(GSSG)的下降,GSH/GSSG的比值无显著变化.GSH排空导致GSH代谢酶活性发生适应性变化,注射BSO后心肌中谷胱甘肽过氧化物酶(GPX)活性与对照组相比显著下降(P < 0.001).注射BSO组与对照组相比,心肌谷氨酰转肽酶(GGT)活性显著增加(P < 0.05).注射BSO力竭组与注射BSO组相比,心肌GGT活性显著增加(P < 0.001),心肌注射BSO抑制γ-谷氨酰半胱酸合成酶(GCS)活性,注射BSO力竭组大鼠心肌GCS mRNA表达量高于注射BSO组,表明极度排空谷胱甘肽后,GCS mRNA表达量的增加可能是机体产生的应激反应. 相似文献
999.
Qing-Qiu Mao Siu-Po Ip Kam-Ming Ko Sam-Hip Tsai Chun-Tao Che 《Progress in neuro-psychopharmacology & biological psychiatry》2009,33(7):1211-1216
The root part of Paeonia lactiflora Pall. (Ranunculaceae), commonly known as peony, is a commonly used Chinese herb for the treatment of depression-like disorders. Previous studies in our laboratory have demonstrated that total glycosides of peony (TGP) produced antidepressant-like action in various mouse models of behavioral despair. The present study aimed to examine whether TGP could affect the chronic unpredictable mild stress (CUMS)-induced depression in mice. The mechanism(s) underlying the antidepressant-like action was investigated by measuring serum corticosterone level, glucocorticoid receptor (GR) and brain-derived neurotrophic factor (BDNF) mRNA levels in brain tissues. CUMS, being lasted for 6 weeks, caused depression-like behavior in mice, as indicated by the significant decrease in sucrose consumption and increase in immobility time in the forced swim test. Whereas serum corticosterone level was significantly increased in mice exposed to CUMS, expressions of GR mRNA in hippocampus, and BDNF mRNA in hippocampus and frontal cortex, were decreased in CUMS-treated mice. Daily intragastric administration of TGP (80 or 160 mg/kg/day) during the six weeks of CUMS significantly suppressed behavioral and biochemical changes induced by CUMS. The results suggest that the antidepressant-like action of TPG is likely mediated by modulating the function of hypothalamic-pituitary-adrenal axis and increasing the expression of BDNF in brain tissues. 相似文献
1000.
目的探讨腹腔镜直肠癌根治术的临床疗效。方法回顾分析2009年7月至2013年3月开展的65例腹腔镜直肠癌根治术和70例开腹直肠癌根治术临床资料,比较两组术中及术后相关指标。应用SPSS16.0软件进行统计学分析,计量资料采用中位数(最小值-最大值)[M(Min—Max)]表示,采用U检验;率的比较采用χ^2检验和Log.rank检验,检验水准0=0.05。结果腹腔镜组手术时间明显长于开腹组手术时间,腹腔镜组出血量明显少于开腹组,120.4(51~285.6)ml比400.5(260.3—890.3)ml,差异有统计学意义(U值=9.357,P=0.009)。两组淋巴结清扫数目差异无统计学意义(P〉0.05)。腹腔镜组术后排气时间、进食时间、尿管留置时间及住院时间均优于开腹组,差异有统计学意义(P=0.045、0.042、0.043、0.043);术后并发症:腹腔镜组切口感染、脂肪液化明显少于开腹组(P=0.047);两组吻合口漏发生率差异元统计学意义(P〉0.05);腹腔镜组术后切口感染、切口疝等并发症少于开腹组(P〈0.05)。结论腹腔镜直肠癌根治术较开腹手术时间较长,但其疗效可靠,手术安全可行,具有微创优势,术中出血少,术后恢复快,住院时间短,并发症少,是治疗结直肠癌重要的手术方法,具有广阔的发展前景。 相似文献