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101.
Flavonoid glycosides were metabolized to phenolic acids via aglycones by human intestinal microflora producing α-rhamnosidase, exo-β-glucosidase, endo-β-glucosidase and/or β-glucuronidase. Rutin, hesperidin, naringin and poncirin were transformed to their aglycones by the bacteria producing α-rhamnosidase and β-glucosidase or endo-β-glucosidase, and baicalin, puerarin and daidzin were transformed to their aglycones by the bacteria producing β-glucuronidase, C-glycosidase and β-glycosidase, respectively. Anti-platelet activity and cytotoxicity of the metabolites of flavonoid glycosides by human intestinal bacteria were more effective than those of the parental compounds. 3,4-Dihydroxyphenylacetic acid and 4-hydroxyl-phenylacetic acid were more effective than rutin and quercetin on anti-platelet aggregation activity. 2,4,6-Trihydroxybenzaldehyde, quercetin and ponciretin were more effective than rutin and ponciretin on the cytotoxicity for tumor cell lines. We insist that these flavonoid glycosides should be natural prodrugs.  相似文献   
102.
BCG对膀胱粘膜结构的影响及肿瘤超微病理的研究   总被引:3,自引:0,他引:3  
应用光镜,透射电镜与扫描电镜技术对20例浅表膀胱肿瘤BCG治疗前后粘膜结构,肿瘤超微结构及Hela细胞表面结构的影响作了比较研究。结果表明,BCG灌注后,膀胱粘膜的结构发生了明显的改变,粘膜层次变薄,粘膜下可见大量单个核细胞浸润,肉芽肿与非干酷淋巴细胞团形成。  相似文献   
103.
采集450例战士血清标本,分别用国家代表株甲3/济防/15/90(H3N2)和甲3/北京/32/92(H3N2)作血清血凝抑制抗体测定,青年对甲3型抗体阳性率为60%~67%,其GMT为34~45。1994~1995年两年中在军营人群中分离到3株H3N2毒株流行株,分别应用国际、国家和地方代表株作抗原性分析,证明流行株与它们之间抗原性有明显差异。本文分离到的3株流行株均上送国家流感中心鉴定,证实为H3N2亚型毒株。  相似文献   
104.
Two experiments were performed to investigate the relationship between the expression of sodium appetite and the appearance of Fos-like immunoreactivity (Fos-IR) in the brain of rats. In the first experiment, rats were depleted of sodium by treatment with furosemide 24 h prior to sacrifice and without access to either food or sodium solution. Some rats had access to distilled water, and others had no fluids available during the 24 h. All of the furosemide-treated rats showed Fos-IR in both the subfornical organ (SFO) and around the organum vasculosum laminae terminalis (OVLT). Rats with access to distilled water during the depletion period showed no Fos-IR in the supraoptic (SON) or paraventricular hypothalamic nuclei (PVN) and, in parallel behavioral studies, comparably-treated rats consumed only 0.3 M NaCl solution at the end of the 24 h. In rats that had no fluids during the deprivation period, only about one half showed Fos-IR in SON and PVN and, in parallel behavioral studies, comparably treated rats consumed both water and 0.3 M NaCI solution at the end of 24 h. In a second experiment, cerebroventricular administration of renin stimulated short latency intake of 0.3 M NaCI and water. The relative intakes of water and NaCl were comparable at a low dose of renin, but intake of water exceeded that of NaCl after higher doses. Renin induced Fos-IR in SFO, MnPO, peri-OVLT region, SON and PVN. Both Fos-IR and fluid intake were antagonized by administration of losartan, an angiotensin 11 type 1 receptor antagonist. Thus, only the circumventricular organs of the lamina terminalis showed Fos-IR during each natriorexigenic regimen in these studies. These data support the view that Ang 11 of both central and peripheral origin activates the SFO and/or peri-OVLT region and contributes to sodium appetite.  相似文献   
105.
将Wistar大鼠随机分成氧化胆固醇组(Och)、纯胆固醇组(Pch)和对照组,分别用氧化胆固醇混合物(250mg/kg bw/d)、纯胆固醇(250mg/kg bw/d)以及悬浮固醇用的明胶液体给大鼠灌胃,连续二天。于第二次灌胃后18小时,从大鼠尾静脉注射伊文思兰溶液,并于注射后2小时处死;取出主动脉用荧光显微分光光度术测定主动脉内膜的通透性。此外,另一部分动物在第二次灌胃后24小时处死,取出主动脉作扫描电镜的内膜观察。结果表明,Och大鼠主动脉内膜的通透性显著高于Pch组与对照组大鼠(P<0.01),而Pch组大鼠主动脉内膜的通透性和对照组无显著差异(P>0.05)。  相似文献   
106.
目的:研究不同种类和强度基牙材料与瓷冠破折碎裂的内在关系.方法:选用计算机建立上颌中切牙的三维有限元模型,模拟陶瓷层、牙本质、核桩等结构.分析在天然齿基牙、钴铬合金基牙及复合树脂基牙情况下,铸造玻璃陶瓷全冠的瓷层内及残余牙本质的应力分布情况.结果:高弹性模量的钴铬合金能够降低瓷层及残余牙本质内的最大主应力和最小主应力峰值,防止瓷层破折碎裂;而弹性模量与牙本质相近的复合树脂桩降低应力峰值的作用不明显.结论:对于有牙髓活力的牙本质基牙,尽量保存牙髓活力后行全冠修复.对于行根管治疗术后的无髓牙,进行核桩冠修复时,采用高弹性模量的高熔合金,尽量避免使用弹性模量较小的复合树脂核.  相似文献   
107.
经颅多普勒频谱参数与急性颅脑损伤患者颅内压的关系   总被引:2,自引:2,他引:0  
目的探讨急性颅脑损伤患者的经颅多普勒频谱参数与颅内压的关系。方法应用TCD检测20例急性中、重型颅脑损伤患者双侧大脑中动脉,同时行颅内压监测。结果经颅多普勒频谱参数cf、PI、af、RI、ae均和ICP正相关,Vd、ac和ICP负相关,其中cf与ICP的相关系数最大。建立TCD相关参数与ICP的多元线性回归方程:ICP=0.312MAP-1.531Vd+21.437PI-15.059ac+38.722cf(P<0.001,R2=0.920估计值的标准差=4.0972mmHg)。结论经颅多谱勒频谱参数可以反应颅脑损伤患者的颅内压的改变。综合研究经颅多谱勒频谱参数、血压与颅内压的关系是应用经颅多普勒无创监测颅内压的方向。  相似文献   
108.
经皮穿刺氩氦刀冷冻治疗肝癌56例临床分析   总被引:11,自引:0,他引:11  
目的 探讨氩氦刀冷冻治疗肝脏恶性肿瘤的临床意义。方法  2 0 0 1年 7月~ 2 0 0 2年6月 5 6例肝脏恶性肿瘤在B型超声引导下行经皮穿刺氩氦刀冷冻治疗。术后患者定期复查血清肿瘤标记物、B型超声检查及CT或MRI。结果 患者肝功能ChildA级 5 0例 ,ChildB级 5例 ,ChildC级 1例。原发性肝癌 4 6例 ,转移性肝癌 10例。小肝癌 (直径≤ 5cm)甲胎蛋白阳性者治疗后转阴占80 % ,甲胎蛋白阴性者治疗后CT或MRI复查病灶完全坏死达 6 1.5 %。转移性肝癌治疗后瘤标降至正常或CT、MRI提示病灶完全坏死者占 6 0 %。结论 氩氦刀冷冻治疗肝脏恶性肿瘤是一种微创、安全、疗效可靠的新方法。对于不适宜行手术治疗的肝脏恶性肿瘤患者是一种有效的微创外科治疗方法。  相似文献   
109.
Measurement of spinal cord evoked potentials (SCEPs) is proposed as a means of predicting locomotion outcome in the rat spinal cord injury (SCI) model. Using 55 rats, three reproducible peak waves (waves I, II and III) were observed during stimulation at the C7 level with recording at the L1 epidural space. Hemisection at the T13 level showed three wave loss patterns: wave III loss only, loss of both wave II and III, and loss of all three waves. Defining an ideal SCI model as establishment of stable monoparesis or paraparesis, all animals in the wave II-III loss group showed favorable results. Histological data and electrophysiological properties allowed reasonable assumptions of wave origin: wave I from extrapyramidal tracts, wave II from the ventral corticospinal tract, and wave III from the dorsal corticospinal tract. Complete destruction of pyramidal tracts in both dorsal and ventral fibers was essential for long-term impairment of locomotion.  相似文献   
110.
Objective:To study whether adenovirus-mediated human β-nerve growth factor (Ad-hNGFβ) gene has any protective effect on blast hearing impairment. Methods:Deafness was induced by blast exposure (172.0 dB) in 30 healthy guinea pigs. On day 7 of blast exposure, Ad-hNGFβ was infused into the perilymphatic space of 20 animals as the study group (hNGFβ group), and artificial perilymph fluid (APF) was infused into the perilymphatic space of the other 10 animals as the control group. At weeks 1, 4 and 8 after blast exposure, the animals were sacrificed and the cochleae were removed for immunohistochemical and HE stainings. Results: Expression of Ad-hNGFβ protein was detected in each turn of the cochlea at the 1st week, with almost equal intensity in all turns. At the 4th week, the reactive intensity of the expression of Ad-hNGFβ protein decreased. At the 8th week, no expression was detectable. The results of HE staining showed that the amount of spiral ganglions in hNGFβ group was significantly greater than that of the control group at week 4 (P〈0.01). Conclusion: Ad-hNGFβ can be expressed at a high level and for a relatively long period in the blast impaired cochlea, suggesting that Ad-hNGFβ has a protective effect on cochlear spiral ganglion cells after blast exposure and the efficient gene transfer into cochlea had been achieved without toxicity.  相似文献   
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