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681.

Aim of the study

This review provides a summary of Mexican medicinal flora in terms of ethnobotanical, pharmacology, and chemistry of natural products related to anticancer activity.

Materials and methods

Bibliographic investigation was carried out by analyzing recognized books and peer-reviewed papers, consulting worldwide accepted scientific databases from the last five decades. Mexican plants with attributed anti-cancer properties were classified into six groups: (a) plant extracts that have been evaluated for cytotoxic effects, (b) plant extracts that have documented anti-tumoral effects, (c) plants with active compounds tested on cancer cell lines, (d) plants with novel active compounds found only in Mexican species, (e) plants with active compounds that have been assayed on animal models and (f) plants with anti-cancer ethnopharmacological references but without scientific studies.

Results

Three hundred plant species belonging to 90 botanical families used for cancer treatment have been recorded, of which only 181 have been experimentally analyzed. The remaining 119 plant species are in use in empirical treatment of diseases consistent with cancer symptomatology. Only 88 of the plant extracts experimentally studied in in vitro cellular models have demonstrated active cytotoxic effects in at least one cancer cell line, and 14 out of the 88 have also been tested in vivo with the results that one of them demonstrated anti-neoplasic effects. A total of 187 compounds, belonging to 19 types of plant secondary metabolites, have been isolated from 51 plant extracts with active cytotoxic effects, but only 77 of these compounds (41%) have demonstrated cytoxicity. Seventeen of these active principles have not been reported in other plant species. However, only 5 compounds have been evaluated in vivo, and 3 of them could be considered as active.

Conclusion

Clearly, this review indicates that it is time to increase the number of experimental studies and to begin to conduct clinical trials with those Mexican plants and its active compounds selected by in vitro and in vivo activities. Also, the mechanisms of action by which plant extracts and their active compounds exert anti-cancer effects remain to be studied.  相似文献   
682.
目的总结同期胰肾联合移植(SPK)术的治疗效果和经验。方法自2002年1月至2003年9月,以SPK术治疗胰岛素依赖型糖尿病(IDDM)合并终末期肾病(ESRD)患者12例。每例受者接受来自同一供者的胰腺和肾脏,移植肾以经典方法植入左侧盆腔,胰腺植于右下腹。1例移植胰腺静脉与受者门静脉系统吻合,11例与体静脉系统吻合。胰腺外分泌引流方法为:3例移植物十二指肠段与受者十二指肠吻合,9例与空肠上段吻合。术前应用甲泼尼龙及抗胸腺细胞球蛋白作为免疫诱导,术后以他克莫司、霉酚酸酯和泼尼松三联抗排斥药物维持。结果术后平均随访时间23个月,受者、移植胰腺和移植肾的存活率分别为100%、91.7%和91.7%。1例再次行SPK术的受者,术后出现了超急性排斥反应,且未能逆转,于术后13d切除移植物;其余11例首次行SPK术的受者中,3例(28.3%)出现急性排斥,均获成功纠治。2例受者术后移植肾功能延迟恢复,行过渡性透析。11例首次行SPK术的移植胰腺术后立即发挥了功能,分别于术后1~5d内停用胰岛素。结论同期胰肾联合移植是胰岛素依赖型糖尿病合并终末期肾病患者的一种安全而有效的治疗方法。  相似文献   
683.
Focal and confluent areas of periventricular hyperintensity have been reported on magnetic resonance (MR) images in 30% of patients over 60 years of age. In order to better understand the pathologic basis of these lesions, the authors studied 14 formalin-fixed brains with MR imaging. Multiple focal areas of hyperintensity were identified in the periventricular white matter in three of the 14 brains studied (21%). Subsequent gross and microscopic pathologic examination of both hyperintense and normal-intensity areas was performed on 87 tissue sections. The larger lesions were characterized centrally by necrosis, axonal loss, and demyelination and therefore represent true infarcts. Reactive astrocytes oriented along the degenerated axons were identified at distances of up to several centimeters from the central infarct. This is called isomorphic gliosis and is associated with increased intensity on T2-weighted images that increases the apparent size of the central lesion.  相似文献   
684.
Objective. To determine the effects of short-term, maximum-tolerated-dose and long-term, optimum-dose iloprost treatment of severe pulmonary hypertension associated with systemic sclerosis (SSc) and the primary antiphospholipid syndrome (APS). Methods. Three patients with SSc and 2 with APS who had failed to respond to oral vasodilator therapy for pulmonary hypertension were enrolled in a 32-week, open, prospective trial. Short-term infusion of maximum-tolerated doses and continuous infusion of optimum doses of iloprost were carried out following baseline cardiac catheterization. Catheterization was repeated at 2 and 32 weeks. All 5 patients completed the study and continued therapy for an average of 82 weeks (range 58–103). Results. Acute infusion of maximum tolerated doses significantly ameliorated the cardiac index (0.92 liters/minute/m2; P < 0.01), pulmonary artery O2 saturation (10.6%; P < 0.05), and pulmonary resistance (−6.7 units; P < 0.05). After 2 weeks of continuous infusion of optimum doses, there was improvement in pulmonary resistance (⩾16%) and pulmonary artery O2 saturation ( > 30%) in the 2 patients with primary APS. After 2 and 32 weeks, the 3 SSc patients showed variable hemodynamic responses. New York Heart Association functional class and exercise tolerance improved in all patients. There was 1 episode of bacteremia, and 1 patient died after 72 weeks of study. Conclusion. Continuous iloprost infusion may improve exercise tolerance and quality of life in patients with severe pulmonary hypertension associated with SSc and primary APS.  相似文献   
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