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四川龙胆系龙胆科龙胆属植物 ,生于山野坡林下及水湿地带主要分布于云南、四川、贵州等地 ,一年生草本植物 ,高 2 .5 8m;茎直立 ,黄绿色 ;叶稍带肉质 ,稍尖 ,两面有光泽 ;根部有很多分枝[1,2 ] 。龙胆科植物在《神农本草经》中作为中品收载[3 ] ,具有泻胆肝火 ,清热燥湿的功效。用于骨间寒热 ,湿热黄疸 ,寒湿脚气 ,咽喉痛 ,目赤 ,口苦 ,阴部湿痒等证 [4]。在临床上广泛应用 ,自 1 91 3年 Ashahina等从该属植物的根部分离得到苦味成分龙胆苦碱( gentiopicrin)以来[5] ,对该属植物的化学成分已有大量研究报道 ,主要含生物碱 ,黄酮类 ,酚类 ,…  相似文献   
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Ten new sesterterpene compounds (4-13) and seven known metabolites (1-3, 14-17) were isolated from the sponge Smenospongia sp. collected from Korean coastal waters. On the basis of combined spectroscopic analyses, the new compounds exhibited diverse functionalities on a common scalarane sesterterpene structure. The presence of a 23-aldehyde on compound 6 and a 20-carboxylic acid on 11 is unprecedented among sponge-derived scalarane sesterterpenes. Several of the new compounds showed significant cytotoxicity and antimicrobial activity, as well as moderate inhibitory activity against isocitrate lyase.  相似文献   
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一71岁韩国男性前额出现孤立的红色斑块。该斑块出现已有1年,并缓慢增大。体检发现前额上正中线部有一轻微隆起的、1.5cm×1.5cm红色斑块。体力活动或情绪应激反应均不诱发该斑块出汗。皮损无疼痛或触痛。患者前额部无外伤史。皮损组织病理检查示外分泌腺数目增加,真皮深部和皮  相似文献   
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Nitric oxide (NO) inhalation therapy has been employed in the management of acute respiratory distress syndrome (ARDS), in order to improve oxygenation. Several factors have been implicated as being responsible for the action of inhaled NO. Alveolar recruitment methods, such as prone positioning and a sufficient positive end expiratory pressure (PEEP), have been identified as having a positive impact on the NO response. A Recruitment maneuver (RM) was introduced for the treatment of ARDS, along with a lung protective strategy. Here, we hypothesized that a RM may further augment the oxygenation of patients treated with NO inhalation. Therefore, the effects of the inhalation of NO, either in combination with a RM, or separately, were evaluated on patients with ARDS for their enhancing action. 23 patients with ARDS were enrolled, and divided into three groups. The patients in group 1 (n=11) were treated with 5 ppm NO via inhalation, followed by a RM, applying a sustained inflation pressure of 30 - 35 cmH2O for 30 seconds. Group 2 (n=6) received a RM alone, while group 3 (n=3) was treated with NO inhalation alone. The oxygenation and hemodynamic parameters were obtained prior to, and 2, 12, and 24 h after, the respective treatment procedures. For group 1, the PaO2/FiO2 increased from its initial value of 171.8 +/- 67.8 to 203.2 +/- 90.0 2 h after NO inhalation. Further improvement was noted with the continual application of the RM reaching, 215.5 +/- 74.6 (p=0.05) and 254.2 +/- 109.5 (p < 0.05), after 12 and 24 h, respectively. Initially 7 of the subjects did not respond to NO inhalation, but 3 of these non-responders changed into responders 12 h after the RM. The changes in the PaO2/FiO2 from baseline at each time period were greater in group 1 than in the other groups, but with no statistical significance. The hemodynamics of the patients was not significantly altered during the entire study period. We conclude that the combined application of NO inhalation and a RM could be beneficial and safe for patients with ARDS, showing an enhancing effect in improvement of oxygenation.  相似文献   
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Neurotrophin treatment has so far failed to prolong the survival of individuals affected with amyotrophic lateral sclerosis (ALS), an incurable motoneuron degenerative disorder. Here we show that intracerebroventricular (i.c.v.) delivery of recombinant vascular endothelial growth factor (Vegf) in a SOD1(G93A) rat model of ALS delays onset of paralysis by 17 d, improves motor performance and prolongs survival by 22 d, representing the largest effects in animal models of ALS achieved by protein delivery. By protecting cervical motoneurons, i.c.v. delivery of Vegf is particularly effective in rats with the most severe form of ALS with forelimb onset. Vegf has direct neuroprotective effects on motoneurons in vivo, because neuronal expression of a transgene expressing the Vegf receptor prolongs the survival of SOD1(G93A) mice. On i.c.v. delivery, Vegf is anterogradely transported and preserves neuromuscular junctions in SOD1(G93A) rats. Our findings in preclinical rodent models of ALS may have implications for treatment of neurodegenerative disease in general.  相似文献   
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Sol-gel transition temperature-controllable Pluronic F127/F68 mixtures including mildly crosslinked alginate and nonsteroidal anti-inflammatory drug (ibuprofen) were prepared to evaluate their potential as tissue adhesion barrier gels. The sol-gel transition temperatures of the Pluronic mixtures could be controlled by adjusting F127/F68 ratio and polymer concentration. The mildly crosslinked alginate with still flow property provided the residence stability of Pluronic mixture gels in the body. Ibuprofen was loaded in Pluronic mixtures to reduce inflammatory response in the body and, thus, to prevent tissue adhesion. The gelation temperatures of the Pluronic mixtures were not affected by the alginate but lowered by the addition of ibuprofen. The in vitro drug release behavior and in vivo peritoneal tissue adhesion of the Pluronic mixtures with the sol-gel transition just below body temperatures were investigated. The drug release behavior from the ibuprofen (1 wt%)-loaded Pluronic mixture gels at 37 degrees C was examined using a membrane-less dissolution model. The drug in the mixture gels was released continuously up to about 45-65% of the total loading amount during the first 7 days. For in vivo evaluation of tissue anti-adhesion potential, the Pluronic mixtures with/without drug were coated on the peritoneal wall defects of rats and their tissue adhesion extents and tissue reactions (inflammatory response, granulation tissue formation, and toxicity in organs) were compared. It was observed that ibuprofen has a positive effect for the peritoneal tissue anti-adhesion. The Pluronic F127/F68/alginate/ibuprofen mixture gel (25 wt% of F127/F68 [7/3], 1 wt% ibuprofen) was highly effective for the prevention of peritoneal tissue adhesion and showed a relatively low inflammatory response and non-toxicity, and thus can be a good candidate material as a coatable or injectable tissue adhesion barrier gel.  相似文献   
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