两种不同碳链烷基吗啉分子的浮选性能对比及性能优化

烷基吗啉是一种新型氯化钠浮选剂,应用于氯化钾工业化生产中的反浮选工艺,文章根据国内氯化钾生产的实际情况,对两种常见的烷基吗啉浮选药剂的浮选性能进行对比研究,并通过添加活化剂,优化浮选药剂性能,达到降低药剂用量的目的.     

Temporally graded, context-specific retrograde amnesia and its alleviation by context preexposure: Effects of postconditioning exposures to morphine in the rat.

Five experiments studied retrograde impairments in Pavlovian fear conditioning following prolonged exposure to the opioid receptor agonist morphine. Injections of morphine commencing 1-7 days but not 14 days after conditioning produced amnesia for that conditioning episode. This amnesia was (a) selective such that morphine impaired freezing to the conditioning context but not to the auditory conditioned stimulus, (b) independent of the interval between the last injection of morphine and test, and (c) accompanied by a failure of contextual discrimination. Context preexposure protected context conditioning and discrimination from the amnestic effects of morphine. These results show that retrograde deficits in contextual fear conditioning are mediated by failures to consolidate a contextual representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intra-Administration Associations and Withdrawal Symptoms: Morphine-Elicited Morphine Withdrawal.

On the basis of a conditioning analysis, some drug "withdrawal symptoms" are conditional responses elicited by stimuli paired with the drug effect. Prior demonstrations of conditional elicitation of withdrawal symptoms evaluated the role of environmental cues; however, pharmacological cues also typically signal a drug effect. Within each administration, early drug onset cues (DOCs) may become associated with the later, larger drug effect (intra-administration associations). This experiment evaluated the contribution of intra-administration associations to withdrawal symptoms. The results indicated that (a) 5 mg/kg morphine elicited behavioral and thermic withdrawal symptoms in rats previously injected on a number of occasions with 50 mg/kg morphine and that (b) DOC-elicited withdrawal symptoms are not a sensitized response to the opiate but rather an associative phenomenon. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Intraadministration associations: Conditional hyperalgesia elicited by morphine onset cues.

There is evidence that exteroceptive cues associated with drug administration elicit conditional compensatory responding (e.g., hyperalgesia in organisms with a history of morphine administration). Recently it has become apparent that, within each administration, interoceptive early-drug onset cues (DOCs) may become associated with the later, larger drug effect (intraadministration associations). The present experiments evaluated DOC-elicited conditional hyperalgesia in rats intravenously infused with morphine. The results indicated that DOC-elicited hyperalgesia contributes to tolerance to the analgesic effect of morphine, and such DOC-elicited hyperalgesia is an associative phenomenon, rather than a sensitized response to the opiate. The findings suggest that associative analyses of tolerance should acknowledge the conditional responding elicited by DOCs, and extinction-based addiction treatments should incorporate extinction of DOC-elicited conditional responding. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Repeated spatial acquisition: Effects of NMDA antagonists and morphine.

Effects of morphine and 2 N-methyl-D-aspartate (NMDA) receptor antagonists, phencyclidine and LY235959, were studied using a within-subject, repeated-acquisition/performance procedure adapted to the Morris Swim Task. In the performance component, subjects swam to a hidden platform that was always in the same location in the pool. In the acquisition component, the platform was moved to a different place for each session. Baseline training produced rapid and direct swims to the platform in the performance component and steep within-session learning curves in the acquisition component. All 3 compounds increased swim distances, escape latencies, and slowed swim speed in a dose-dependent manner, but only morphine consistently produced selective impairments on acquisition. NMDA antagonists generally affected acquisition only at doses that also disrupted performance, although phencyclidine produced selective effects in some animals. These outcomes were different than those from studies of response chains in primates, suggesting that task and species variables may be important determinants of drug effects on acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Construction of the Subtracted cDNA Library of Striatal Neurons Treated with Long-term Morphine

Objective To construct a morphine tolerance model in primarily cultured striatal neurons,and screen the differentially expressed genes in this model using suppression subtractive hybridization (SSH).Methods Sbtracted cDNA libraries were constructed using SSH from normal primarily cultured striatal neurons and long-term morphine treated striatal neurons (10-5 mol/L for 72 hours).To check reliability of the cell culture model,RT-PCR was performed to detect the cAMP-responsive element-binding protein (CREB) mRNA expression.The subtracted clones were prescreened by PCR.The clones containing inserted fragments from forward libraries were sequenced and submitted to GenBank for homology analysis.And the expression levels of genes of interest were confirmed by RT-PCR.Results CREB mRNA expression showed a significant increase in morphine treated striatal neurons (62.8S±1.98) compared with normal striatal neurons (28.43±1.46,P<0.01).Thirty-six clones containing inserted fragments were randomly chosen for sequence analysis.And the 36 clones showed homology with 19 known genes and 2 novel genes.The expression of 2 novel genes,mitochondrial carrier homolog 1 (Mtchl; 96.81±2.04 vs.44.20±1.31,P<0.01) and thymoma viral proto-oncogene 1 (Aktl; 122.10±2.17 vs.50.11±2.01,P<0.01),showed a significant increase in morphine-treated striatal neurons compared with normal striatal neurons.Conclusions A reliable differential cDNA library of striatal neurons treated with long-term morphine is constructed.Mtchl and Aktl might be the candidate genes for the development of morphine tolerance.     

A molecularly imprinted polymer for the efficient adsorption of morphine

Molecularly imprinted polymers (MIPs) were synthesized via the precipitation polymerization technology for the specific adsorption of morphine. A number of polymers (methacrylic acid, trifluoromethyl acrylic acid, and acrylamide) were studied, respectively, as the precursor monomers under various synthetic conditions (the imprinting (IP) ratio, cross-linking (CL) ratio, solvent ratio, reaction temperature, etc.). The MIP with optimal performance was derived using methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the crosslinker, and azobisisobutyronitrile (AIBN) as the initiator, with an IP ratio of 1:3 and a CL ratio of 5:1. This MIP presented a maximum morphine adsorption capacity of 38.24 mg/g (one of the highest capacities ever reported in the literature) at a bulk morphine concentration of ~230 ppm in acetonitrile solution. The adsorption capacity, selectivity, reusability, as well as the chemical and mechanical stabilities of the MIP were confirmed by the adsorption experiments, instrumental characterization, thermodynamic analysis, as well as the proposed mechanisms.     

固相萃取-液相色谱-串联质谱法检测血液中海洛因及其代谢产物

建立了固相萃取-液相色谱-串联质谱（SPE-LC-MS/MS）法分析吸毒者血样中的O⁶-单乙酰吗啡、吗啡、3-β-D-葡萄糖醛酸吗啡。以3-β-D-葡萄糖醛酸吗啡-d₃为内标,选取Oasis HLB为固相萃取柱,Atlantis^TM dC18（150 mm×3.9 mm×5 μm）色谱柱为分析柱,采用甲醇-0.1%甲酸水溶液为流动相进行梯度洗脱;采用电喷雾正离子电离源,多反应监测（MRM）扫描方式,通过两对母离子/子离子和保留时间定性定量检测目标化合物。结果表明：血样中O⁶-单乙酰吗啡、吗啡、3-β-D-葡萄糖醛酸吗啡的检测限为3~5 μg/L,线性关系良好,相关系数均在0.997 5以上;添加50、500、1 000 μg/L加标水平后,O⁶-单乙酰吗啡、吗啡、3-β-D-葡萄糖醛酸吗啡的平均回收率为80.6%~98.9%,准确度为-7.3%~9.1%。该方法具有较高的灵敏度和选择性,可用于实际案件中海洛因及其代谢产物的检测。     

吗啡及可待因酶联免疫检测方法的研究

通过对吗啡分子结构进行改造,制备了吗啡半抗原及人工抗原,通过免疫动物得到了吗啡的单克隆抗体,建立了吗啡及可待因间接竞争酶联免疫检测方法。该方法对火锅底料和辣椒酱的检出限分别为4.92 μg/kg、4.85 μg/kg,半抑制浓度(IC50)为0.7 μg/L,标准曲线线性范围为0.3～24.3 μg/L。抗体与吗啡、可待因的交叉反应率分别为100%、150%。火锅底料、辣椒酱样品中平均添加回收率为80%～120%,变异系数＜15%。     

Morphine promotes autonomic learning.

Morphine (0.01-10 mg/kg) promoted rapid autonomic learning of discriminative, Pavlovian conditioned heart rate decelerations to tone signals in male and female rabbits, and the higher doses (1-10 mg/kg) promoted decelerative heart rate orienting reflexes to novel tones. Morphine does dependently reduced heart rate acceleration to signaled shock but had no effect on heart rate acceleration to unsignaled shock. Morphine did not impair retention of cardiac conditioned reflexes, and its U-shaped dose effect, increasing conditioned heart rate discrimination early in training, reappeared in extinction. The authors propose that morphine promotes autonomic learning of preparatory, compensatory reflexes to signaled stressors that reduce their stressful effects. This action may mimic the normal, adaptive function of an endogenous messenger released by the Pavlovian contingency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)