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Context Opioids have been used as the reference treatment on chronic pain. However, they are related to serious adverse effects which affect the patient compliance to treatment, as well as, his quality of life. Particulate formulations have been investigated as an alternative to improve opioid efficacy and safety. Objective Summarise the available studies concerning micro and nanoencapsulated opioid formulations discussing their biopharmaceutical characteristics, such as composition, size, in vitro release, pharmacokinetic and antinociceptive profile. Methods Papers available in 1995–2015 at Medline, Science Direct and Web of Science databases were collected and assessed. Searches were performed using varied combinations of the keywords of this work. Results Opioid-loaded particles showed prolonged drug release with maintenance of serum therapeutic concentrations and extended analgesia when compared with the free drugs. The side effects incidences were reduced or maintained the same. Conclusion Particulate formulations can significantly increase both potency and safety profiles of opioids.  相似文献   
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The agreement between theoretical and experimental vibrational circular dichroism curves of (4R,9R,10R)-(+)-african-1(5)-ene-2,6-dione (1) and (4R,9S,10R)-lippifoli-1(6)-en-5-one (2), isolated from the widely used plant Lippia integrifolia, allowed the determination of the conformation and absolute configuration of 1 and confirmed both structural features for 2. Molecular modeling of 1 and 2 was carried out by means of a systematic and a Monte Carlo search protocol followed by geometry optimization employing density functional theory calculations with the B3LYP/6-31G(d), B3LYP/DGDZVP, and/or B3PW91/DGDZVP2 functionals/basis sets. Validation of the minimum energy conformations for both tricyclic substances was achieved by comparison of the experimental and theoretical vicinal (1)H-(1)H NMR coupling constants obtained by DFT-GIAO calculations.  相似文献   
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OBJECTIVE: Using a mouse embryo bioassay, we examined the embryotoxic properties of serum obtained from eight women who had ingested cocaine base paste (CBP) for a period of 1-3 years. STUDY DESIGN: Two-cell stage mouse embryos were cultured in the presence of serum extracted from eight CBP-smoking or control women. After 48h, embryos were evaluated to determine their developmental stage and then processed by Tarkoswki's technique to determine the proportion of embryos with micronuclei, in order to establish the number of micronuclei/embryo. RESULTS: Serum from CBP patients diminished the percentage of embryos progressing to the compacted morula stage, while increasing the proportion of embryos with micronuclei and the corresponding micronuclei/embryo ratio. CONCLUSION: These findings provide the first experimental evidence of embryotoxic compounds in the serum of CBP-smoking women. This study highlights the reproductive risk of chronically ingested CBP and demonstrates the need for further studies.  相似文献   
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BACKGROUND: Pure heterologous sarcomas of the uterine corpus are extremely rare, accounting for 4% of all uterine sarcomas. Primary chondrosarcoma, which is characterized by the absence of epithelial or other heterologous mesenchymal elements, is included in this group. To this date, only 17 cases, including the presenting case, have been reported. CASE: A 55-year-old female presenting with post-menopausal bleeding was diagnosed with chondrosarcoma of the uterus, after abdominal hysterectomy and bilateral salpingoophorectomy. After 8 months of surgery, there is no evidence of recurrence after receiving external radiotherapy and brachytherapy. CONCLUSION: Primary chondrosarcoma of the uterus is an extremely rare uterine tumour most frequently diagnosed by the pathologist. They are usually aggressive malignant tumours with an early relapse and metastases.  相似文献   
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OBJECTIVE: To assess whether supracervical hysterectomy (SCH) is a reasonable alternative to total abdominal hysterectomy in patients with advanced ovarian cancer. METHODS: We reviewed the records of patients with advanced ovarian cancer who underwent a SCH at one institution between 1993 and 2004 and a similar cohort who underwent total abdominal hysterectomy (TAH) at the same institution during the same period. Patients without complete surgical staging done at the institution were excluded. Independent-sample t tests, Fisher exact test, and log rank tests were used for statistical analysis. RESULTS: The study included 47 patients who underwent SCH (mean age, 59.6 years) and 190 who underwent TAH. There were no significant differences between the two groups in age (P=.51), preoperative CA 125 level (P=.55), or receipt of taxane-based and platinum-based chemotherapy (P=.84). Although limited by sample size, there were no significant differences between the two groups in rates of intraoperative complications (4 of 47 in the SCH group, or 8.5%, compared with 7 of 190 in the TAH group, or 3.7%; P=.24), vaginal or cervical recurrence (5 of 47 in the SCH group, or 10.6%, compared with 22 of 190 in the TAH group, or 11.6%; P=1.00), or in progression-free survival (SCH of 1.01 years compared with TAH of 1.19 years; P=.64) or overall survival (SCH of 3.28 years compared with TAH of 3.36 years; P=.12). CONCLUSION: Supracervical hysterectomy may be a reasonable alternative to TAH in patients with advanced ovarian cancer. LEVEL OF EVIDENCE: II.  相似文献   
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