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1.
The observation of the immunomodulatory effects of opioid drugs opened the discussion about possible mechanisms of action and led researchers to consider the presence of opioid receptors (OR) in cells of the immune system. To date, numerous studies analyzing the expression of OR subtypes in animal and human immune cells have been performed. Some of them confirmed the expression of OR at both the mRNA and protein level, while others did not detect the receptor mRNA either. Although this topic remains controversial, further studies are constantly being published. The most recent articles suggested that the expression level of OR in human peripheral blood lymphocytes could help to evaluate the success of methadone maintenance therapy in former opioid addicts, or could serve as a biomarker for chronic pain diagnosis. However, the applicability of these findings to clinical practice needs to be verified by further investigations. 相似文献
2.
Tao TIAN Chao-lan ZHANG Feng ZHU Shan-xin YUAN Ying GUO Sheng-guo XUE 《中国有色金属学会会刊》2021,31(5):1484-1495
A column experiment was conducted to investigate the effect of phosphogypsum (PG) on the saline- alkalinity, and aggregate stability of bauxite residue. Results showed that: with increasing leaching time, the concentrations of saline-alkali ions decreased while the concentration increased in bauxite residue leachate; compared with CK (control group) treatment, pH, electric conductivity (EC), exchangeable sodium percentage (ESP), sodium absorption ratio (SAR), and exchangeable Na+ content of bauxite residue were reduced following PG treatment; average particle sizes in aggregates following CK and PG treatments were determined to be 155 and 193 nm, respectively. SR-μCT test results also confirmed that bauxite residue following PG treatment acquired larger aggregates and larger pore diameter. These results indicate that the PG treatment could significantly modulate the saline-alkalinity, and simultaneously enhance aggregate stability of bauxite residue, which provides a facile approach to reclaim bauxite residue disposal areas. 相似文献
3.
《Ceramics International》2021,47(24):33956-33971
Ablative composites have been in use for thermal protection of space vehicles for decades. Carbon-phenolic composites have proven to perform exceptionally well in these applications. However with development in aerospace industry their performance needs improvement. In this field, different carbon-based and ceramic additives have been introduced into ablative composite systems. This review article gives a comparative analysis of researches done in this field in the recent past. Density, ablative, thermal and mechanical properties of ablative composites with different ultra-high temperature ceramic particles i.e. ZrSi2, Cenosphere, nano-SiO2, BN etc. and carbon-based nanoparticles i.e. CNTs, nano-Diamonds, Graphene oxide etc. used as additives, have been compared and discussed. Emphasis is put on carbon-phenolic composite systems although some epoxy matrix systems have also been discussed for comparison. 相似文献
4.
Aram Ismail Elizabeth Lewis Birgitta Sjdin Bengt Mannervik 《International journal of molecular sciences》2021,22(8)
Glutathione transferases (GSTs) form a family of detoxication enzymes instrumental in the inactivation and elimination of electrophilic mutagenic and carcinogenic compounds. The Pi class GST P1-1 is present in most tissues and is commonly overexpressed in neoplastic cells. GST P1-1 in the dog, Canis lupus familiaris, has merits as a marker for tumors and as a target for enzyme-activated prodrugs. We produced the canine enzyme CluGST P1-1 by heterologous bacterial expression and verified its cross-reactivity with antihuman-GST P1-1 antibodies. The catalytic activity with alternative substrates of biological significance was determined, and the most active substrate found was benzyl isothiocyanate. Among established GST inhibitors, Cibacron Blue showed positive cooperativity with an IC50 value of 43 nM. Dog GST P1-1 catalyzes activation of the prodrug Telcyta, but the activity is significantly lower than that of the human homolog. 相似文献
5.
Dr. Tom Baladi Dr. Nedra Hamouda-Tekaya Dr. Leticia Christina Pires Gonçalves Dr. Stéphane Rocchi Dr. Cyril Ronco Dr. Rachid Benhida 《ChemMedChem》2020,15(13):1113-1117
Sulfonylguanidines are interesting bioactive compounds with a broad range of applications in the treatment of different pathologies. 2-Aminobenzazole-based structures are well employed in the development of new anticancer drugs. Two series of novel N-benzazol-2-yl-N′-sulfonyl guanidine derivatives were synthesized with the sulfonylguanidine in either an extra- or intracyclic frame. They were evaluated for their antiproliferative activity against malignant melanoma tumor cells, thus allowing structure-activity relationships to be defined. Additionally, NCI-60 screening was performed for the best analogue to study its efficiency against a panel of other cancer cell lines. The stability profile of this promising compound was then validated. During the synthetic process, an unexpected new deamidination of the sulfonylguanidine towards sulfonamide function was also identified. 相似文献
6.
Xiang-feng KONG Xing-xing JIANG Sheng-guo XUE Ling HUANG William HARTLEY Chuan WU Xiao-fei LI 《中国有色金属学会会刊》2018,28(3):534-541
Bauxite residue, a highly saline solid waste produced from digestion of bauxite for alumina production, is hazardous to the environment and restricts vegetation establishment in bauxite residue disposal areas. A novel water leaching process proposed here was used to investigate the dynamic migration and vertical distribution of saline ions in bauxite residue. The results show that water leaching significantly reduced the salinity of bauxite residue, leaching both saline cations Na+, K+, Ca2+ and anions CO2?3, SO2?4, HCO?3. Na+ and K+ migrated from 40–50 to 20–30 cm of the column, presenting a high migration capacity. The migration capacity of Ca2+ was lower and accumulated at 30–40 cm of the column. CO2?3 initially distributed at 20–30 cm of the column, subsequently transported to 30–40 cm of the column, and finally returned to 20–30 cm of the column along with evaporation. SO2?4 was originally distributed at 40–50 cm, but finally migrated to 20–30 cm of the column. Nevertheless, HCO?3 remained at the bottom of the column, and its migratory was less affected by evaporation. 相似文献
7.
Julie Babyar 《Drug development and industrial pharmacy》2018,44(11):1868-1870
Substandard, falsified, and counterfeit medications are a concern for the industry and for the public’s health. Data collection and research on these illegitimate drugs must continue to be a priority and common recommendations must be implemented immediately. The health of the public continues to be at risk, and as such global consensus and collaboration must be swift. Process improvements and policy decisions can support expert recommendations while technology and research continue to drive home change. Addressing counterfeit and substandard drugs is cost effective, feasible, and the right thing to do. 相似文献
8.
9.
目的建立气相色谱-三重四极杆质谱(gas chromatography-triple quadrupole mass spectrometry,GC-MS/MS)测定糙米中氟虫腈及其代谢产物氟甲腈、氟虫腈砜、氟虫腈硫醚残留的的分析方法。方法糙米加水涡旋混匀后乙腈提取,通过N-丙基乙二胺(primary secondary amine,PSA)、C_(18)粉末、石墨化炭黑(graphitized carbon black,GCB)粉末净化提取液,气相色谱-三重四极杆质谱多重反应离子监测模式(multiple reaction monitoring,MRM)检测,以外标法定量。结果在1~50μg/L范围下,氟虫腈及其代谢物具有良好的线性关系,相关系数(r)均大于0.99,在2、10、20μg/kg 3个添加水平下,氟虫腈及其代谢物的平均回收率为91.6%~109.9%,相对标准偏差(relative standard deviation,RSD)为4.3%~6.3%。氟虫腈及其代谢物在糙米中的定量限为0.2~0.5μg/kg,定量限添加回收率在85.0%~108.0%,RSD为5.9%~6.9%。结论该方法操作简单快速、试剂耗材消耗少、灵敏度高,适用于快速处理大批量糙米中氟虫腈及其代谢产物的残留量检测。 相似文献
10.
目的建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)同时测定保健品中非法添加的降糖减脂和利尿类药物的分析方法。方法样品用甲醇-水溶液(50:50,V:V)经超声提取,经C_(18)色谱柱(50 mm×2.1 mm,2.6μm)分离,以0.1%(V/V)甲酸-10 mmol/L乙酸铵水溶液和乙腈作为流动相,进行梯度洗脱。在正电喷雾离子(positiveelectrospray ionization,ESI~+)源采用多反应监测(multiple reaction monitoring,MRM)模式检测。结果 3类非法添加药物在1.0~50.0 ng/mL范围内(洛伐他汀羟酸钠盐为10~500 ng/mL)线性均良好,相关系数(r~2)均在0.99以上。3类非法添加的药物在0.1、0.5和1.0μg/g 3水平(洛伐他汀羟酸钠盐的加标量为1.0、5.0和10.0μg/g)下的加标回收率为77.15%~116.61%,相对标准标准偏差(relative standard deviations,RSDs)均未超过10.65%(n=6)。结论本方法简单、快速、可靠、灵敏度高,可满足保健品市场的监管和检验需求。 相似文献