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41.
郝建新 《北京中医药大学学报(中医临床版)》2002,9(1):34-37
上世纪末曾有人提出我国的中药产业将成为本世纪的“朝阳产业”,口号甚是鼓舞人心。但结合我国中药产业的现状分析,却不容乐观。想在本世纪的头几年达到蓬勃兴盛的状态可能还有很大差距。问题在哪里,笔者以为,除了中药生产企业本身存在诸多问题外,关键还在于针对中药学本身的现代研究没有取得明显的突破性进展。以致我国有关中药研发的政策、法 相似文献
42.
本文报告用亚致死剂量的 S—31183(类保幼激素)处理三带喙库蚊幼虫对其发育影响的研究,结果表明处理后蛹期死亡率明显高于幼虫期,并且与剂量大小有关。S—31183处理幼虫并不影响幼虫的发育时间,但可使幼虫化蛹时蜕皮受阻与羽化受到一定的抑制。 相似文献
43.
44.
目的:研究治疗前列腺增生的α1-受体拮抗剂SL-89.0519-08的合成路线。方法:以5-氯-2-甲氧基苯胺为原料,经环合,烃化,脱保护基和亲核取代等步骤,合成了目标化合物,同时对原料合成工艺进行了摸索。结果:合成的目标化合物经IR,^1HMNR,EI-MS和HRMS得以确证。结论:该合成工艺和路线适宜工业化生产。 相似文献
45.
应用皮瓣移植修复足跟部皮肤软组织缺损 总被引:9,自引:2,他引:7
目的通过8种不同皮瓣的临床应用,总结足跟部皮肤软组织缺损的修复效果。方法采用了游离足背皮瓣、游离背阔肌皮瓣、游离肩胛皮瓣、桥式胫后动脉岛状皮瓣、桥式携带背阔肌皮瓣或桥式携带肩胛皮瓣、胫后动脉岛状皮瓣、胫后动脉皮支岛状皮瓣、跖底内侧动脉岛状皮瓣,对足跟部皮肤软组织缺损进行修复的临床应用。结果95块皮瓣修复足跟部皮肤软组织缺损,成活93块,成功率为97.9%。随访1~15年,治疗效果满意。结论应用皮瓣移植的方法,才能使足跟部皮肤软组织缺损得到有效的修复。 相似文献
46.
目的:探讨腹腔镜在腹股沟疝修补手术中的优缺点,方法:31例腹股沟疝行腹腔镜疝修补术,其中斜疝25例,直疝6例,复发疝4例,均行腹腔内术式(TAPP)。结果:手术全部完成,平均手术时间61min(40-95min),无中转手术,4例同时行胆囊切除术,平均住院7.5d,术后近期随访无复发,结论:腹腔镜疝修补术是一种安全的手术,术后恢复时间短,复发率低。 相似文献
47.
Jing‐Ping Zhang Limin Zheng Jiang‐Hai Wang Karl‐Eric Magnusson Xin Liu 《Phytotherapy research : PTR》2009,23(6):844-850
Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
48.
目的探讨NO合成底物左旋-精氨酸(L-Arg)对兔局灶脑缺血后血管再生和脑细胞凋亡的影响。方法兔局灶脑缺血后应用L-Arg,流式细胞仪定量分析细胞凋亡率的变化,CD34免疫组织化学测脑组织微血管密度(MVD),脑组织含水率评价脑水肿。结果与对照组比较,L-Arg组脑细胞凋亡率明显减少(8.72±2.62 vs 16.62±2.82,P<0.01),同时脑组织MVD却明显增加(1.21±0.43 vs 0.69±0.22,P<0.01)。结论外源性L-Arg可减少缺血后脑细胞凋亡并促进缺血后血管再生,对局灶脑缺血具有重要的神经保护作用。 相似文献
49.
目的:探讨清炎颗粒治疗肾盂肾炎的免疫学机制。方法:采用孙氏方法改进造模,治疗组分别按剂量3.12、6.24、12.48g·kg^-1·d^-1予清炎颗粒,模型组予生理盐水,对照组予至灵胶囊灌胃,喂养至3d、7d、15d、30d、60d取血清,用ELISA法检测其IL-8、IL-10的水平。结果:清炎颗粒能显著降低不同时段血清IL-8的水平、提高不同时段血清IL-10的水平。结论:免疫调控可能是清炎颗粒治疗肾盂肾炎的作用机制之一。 相似文献
50.
BACKGROUND: As a non-invasive technique which can provide comprehensive biological information, 1H-magnetic resonance spectroscopy (1H-MRS) may provide valuable reference data for irreversible recovery or reversible changes in ischemic tissue after stroke.
OBJECTIVE: To monitor and evaluate the effect of the urokinase thrombolytic therapy after experimental acute cerebral ischemia by 1H-MRS technology and investigate its adaptability.
DESIGN: Randomly controlled animal study.
SETTINGS: Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science.
MATERIALS: Eleven healthy adult Sprague-Dawley (SD) rats, weighing 260–300 g and of both genders, were supplied by Experimental Animal Center of Tongji Medical Collage, Huazhong University of Science and Technology [SCXK (e) 2004-007]. 4.7T superconducting nuclear magnetic resonance meter was provided by Brucker Company.
METHODS: The experiment was carried out in Shenzhen Hospital of Peking University and National Key Laboratory of Pattern and Atom & Molecular Physics, Wuhan Physics and Mathematics Institute, Chinese Academy of Science from August 2003 to December 2005. ① The rats were randomly divided into 30-minute self-thrombo-embolism group (n =6) and 60-minute self-thrombo-embolism group (n =5). Six rats in 30-minute self-thrombo-embolism group were occluded with clot embolus for 30 minutes and 5 rats in 60-minute self-thrombo-embolism group were occluded for 60 minutes. 10 000 U/kg urokinase was dissolved in 2 mL saline and the operation lasted for 5 minutes. ② 1H-MRS was performed before thrombolysis and at 3 hours and 24 hours after successful embolization. The metabolic changes of N-acetyl-L-aspartic acid (NAA)/phosphocreatine (PCr) + creatine (Cr), choline phosphate (Cho)/PCr+Cr and lactic acid (Lac)/PCr+Cr in the region of interests were analyzed. ③ The T2W image was conducted 24 hours after the thrombolytic therapy with TR=500 ms and TE=25 ms. ④ The subjects were sacrificed immediately after 1H-MRS and the brain tissues were cut into pieces and stained with HE method; in addition, pathological changes were observed under optic microscope.
MAIN OUTCOME MEASURES: ① Metabolic changes of NAA/PCr+Cr, Cho/PCr+Cr and Lac/PCr+Cr in the region of interests; ② T2W image at 24 hours after the thrombolysis; ③ pathological observation of brain tissue.
RESULTS: Eleven rats were all involved in the final analysis. ① Metabolic changes in the region of interests : In 30-minute self-thrombo-embolism group, the Lac peak emerged immediately after the embolism, but the ischemic zone decreased 3 hours after the thrombolytic therapy (0.252±0.01, 0.603±0.01, P < 0.01). Lac/(PCr+Cr) ratio was 0.290±0.01 at 24 hours after thrombolysis, which was higher than that at 3 hours after thrombolysis (P < 0.01). The NAA/ (PCr+Cr) ratio decreased significantly at 3 hours after the thrombolysis as compared with that before thrombolysis (0.922±0.16, 1.196±0.01, P < 0.05). In 60-minute self-thrombo-embolism group, the Lac/(PCr+Cr) ratio was higher at 3 hours after thrombolysis than that before thrombolysis (0.846±0.12, 0.601±0.11, P < 0.05) and the NAA/(PCr+Cr) decreased at 3 hours after the embolism. Fluctuation of NAA/ (PCr+Cr) ranged from 0.68 to 0.75 before thrombolysis and from 0.71 to 0.75 at 3 hours after thrombolysis. ② T2W image: T2W image showed that 2 subjects in 30-minute self-thrombo-embolism group whose Lac/NAA was higher than 0.7 suffered from intracranial hemorrhage. This meant that the subjects with Lac/NAA > 0.7 were more likely to suffer from intracranial hemorrhage. ③ Histological and morphological examinations: Optic microscope demonstrated that interspace surrounding nerve cells was widened at ischemic center; neurons were swelling; nucleus was stained lightly; pyknosis and mesenchymal edema were mainly observed in lateral cortex of brow and vertex and in lateral part of corpus striatum.
CONCLUSION: ①Compound parameters in ischemic area before thrombolysis should be regarded as an important predicting marker for thrombolytic therapy, effect evaluation and termination. ② 1H-MRS combining with other imaging technique is a detecting way for screening cases who are suitable for thrombolytic therapy. 相似文献