Preparation and characterisation of MCM-41 materials with intra-wall cross-mesopores

Micro & nano letters

article

Weixing Ming¹  Jinghong Ma¹  Yan Wang¹  R. Li¹ 

[1] College of Chemistry and Chemical Technology, Institute of Special Chemicals, Taiyuan University of Technology

关键词: mesoporous materials;    X-ray diffraction;    adsorption;    transmission electron microscopy;    MCM-41 material;    intrawall cross-mesopore;    pre-organo-functionalised fumed silica;    X-ray diffraction;    nitrogen-argon adsorption;    transmission electron microscopy;    hexagonally arranged channels;    interconnected structural mesopores;    n-heptane;    low-concentration volatile organic compounds;   

DOI  :  10.1049/mnl.2015.0078

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

Background: Preemptive analgesia establishes effective antinociception before surgery and continuation of this effective analgesic level well into the postoperative period. Butorphanol tartrate and pentazocine lactate are opioid analgesics with mixed agonist-antagonist properties. Aim: The aim of the present study was to compare the preemptive analgesic effect of butorphanol and pentazocine given by intramuscular (IM) route as a primary outcome. Secondary outcome was to compare hemodynamic parameters and the side effects profile. Methodology: A comparative randomized, single blind, and prospective clinical study in sixty patients ASA physical status I and II was carried out. Patients were demographically similar. Patients were randomized to receive either a butorphanol injection (Group B) 2 mg (n=30) or pentazocine injection (Group P) 60 mg (n=30) both IM 60 min before surgery. Lower abdominal surgeries under spinal anesthesia were selected. Duration of pain relief was recorded by visual analogue scale (VAS) postoperatively up to 24 h. Sedation was measured with Cook’s sedation score system. Patients were observed for any change in vital signs and any other side effect for 24 h. Rescue analgesia in the form of IM diclofenac sodium 75 mg was given when VAS≥3. Results: Duration of analgesia was up to 18 h in Group P while it was extended in Group B, but this was statistically not significant. Requirements of rescue analgesia were higher and occurred earlier in Group P, although not statistically significant. Sedation score was also comparable. Hemodynamic changes were not significant with the exception of an increase in mean arterial pressure in Group P. No severe side effects were observed in any patient of either group. Conclusion: Butorphanol a mixed agonist-antagonist opioid in the dose of 2 mg IM is an acceptable alternative to pentazocine as a pre-emptive analgesic due to longer duration of analgesia and greater analgesic efficacy with low incidence of side effects.

【 授权许可】

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