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991.
脱钙冻干骨修复种植周骨缺损的扫描电镜观察   总被引:2,自引:0,他引:2  
目的比较脱钙冻干骨(DFDB)、脱钙冻干骨复合人重组骨形成蛋白-2(rhBMP-2)、脱钙冻干骨联合钛膜的骨修复能力。方法 3条犬股骨种植体周形成4 mm×3 mm×3 mm的骨缺损,分别植入上述3种不同材料。术后4、8、12周分期处死动物,取含种植体的骨段进行扫描电镜观察,观察新骨形成情况及其与种植体之间的缝隙。结果 DFDB可单独用于修复种植体周骨缺损,但成骨作用较慢;DFDB+rhBMP-2和DFDB+钛膜能较早诱导新骨形成,加速骨整合过程。结论DFDB是一种较理想的骨修复材料,复合rhBMP-2或与钛膜联用时效果更佳。  相似文献   
992.
Riddelliine alters hepatocellular and endothelial cell kinetics and function including stimulating an increase in hepatocytic vascular endothelial growth factor (VEGF) in the absence of increased serological levels of VEGF (Nyska etal. 2002). The objective of this study was to further assess hepatic VEGF and KDR/flk-1 synthesis and expression by hepatic cells under riddelliine treatment conditions. Forty-two male F344/N rats were dosed by gavage with riddelliine (0, 1.0, and 2.5 mg/kg/day) for 6 weeks. Seven animals/group were sacrificed after 8 consecutive daily doses; remaining rats were terminated after 30 daily doses, excluding weekends. Hepatic tissues were evaluated by immunohistochemistry and in situ hybridization. The results showed that VEGF mRNA expression was observed in control and treated animals; however, qualitative differences were noted. Treated animals exhibited VEGF mRNA in clustered, focal hepatocytes and bile duct epithelium, whereas VEGF mRNA in hepatocytes from vehicle control rats was distributed evenly across all hepatocytes. Results evaluating the distribution of the VEGF cognate receptor, KDR/flk-1 showed that randomly distributed, rare sinusoidal endothelium, including those demonstrating karyomegaly and cytomegaly expressed KDR/flk-1. Phosphorylation of KDR/flk-1 at pTyr996 and pTyr1054/1059, but not pTyr951, was also detected, evidence that endothelial cell KDR/flk-1 was activated. These results suggest that both hepatocytes and endothelial cells are targets of riddelliine-induced injury. We speculate that damage to both populations of cells may lead to dysregulated VEGF synthesis by hepatocytes and activation of KDR/flk-1 by endothelium leading to the induction of sustained endothelial cell proliferation, culminating in the development of hepatic hemangiosarcoma.  相似文献   
993.
补肾活血法对子宫内膜异位症模型大鼠细胞凋亡的影响   总被引:3,自引:0,他引:3  
目的 探讨补肾活血法治疗子宫内膜异位症的细胞凋亡机制. 方法 将雌性8~12周龄SD大鼠分为模型组、西药组、中药组及中西药合并组,每组15只.造模成功后,分别给药4周,采用光镜、电镜、TUNEL法及免疫组化法检测药物干预前后模型大鼠异位子宫内膜的病理形态学、凋亡细胞的阳性率及凋亡调控蛋白bcl-2、bax的阳性表达. 结果 中西药合并组的异位内膜组织发生凋亡的改变最为明显,凋亡指数最高,并可明显下调bcl-2蛋白的阳性表达和提升bax蛋白阳性的表达,从而使bcl-2/bax比值下降,其次为中药组、西药组和模型组. 结论 子宫内膜异位症的发生与细胞凋亡能力的下降有关.补肾活血中药能促进异位内膜细胞发生凋亡,使异位病灶萎缩、消退细胞.  相似文献   
994.

Background

Motherwort has been used as medicinal herb for many years in both China and Europe. In particular, Chinese motherwort has been commonly used to treat disorders of mammary gland in Chinese traditional medicine (TCM). Chinese motherwort aqueous extract (MAE) was previously reported to have anti-cancer activity in breast cancer cells with low potency (IC50s in a range of 8–40 mg/mL). However, treatment of motherwort ethanol extract in vivo markedly suppressed the development of uterine adenomyosis and mammary cancers in mice. Therefore, anti-cancer activity of Chinese motherwort, especially in a form of ethanol extract, needs to be confirmed further at cellular level.

Materials and methods

Aerial part of Chinese motherwort (Leonurus japonicus Houtt) dry powder is extracted with 70% ethanol and the chemical components were characterized with HPLC finger print as well as mass spectrometry. Cytotoxicity of the motherwort aqueous ethanol extract (MAEE) was analyzed with MTT assay on ER negative MDA-MB-231 and ER positive MCF-7 human breast cancer cell lines. Hoechst 33342 staining and flow cytometry were used to verify whether the cell death induced by MAEE is apoptosis in nature. Cell cycle status of MAEE treated cells were analyzed with flow cytometry.

Results

Our results showed that MAEE caused cell death in a dose-dependent and time-dependent fashion in both ER positive and negative breast cancer cells. Morphology, Hoechst 33342 staining and flow cytometry evidence all indicated the cell death is not in an apoptotic nature. Furthermore, low concentrations of MAEE caused cell cycle arrest at G2/M phase.

Conclusions

These data suggest that Chinese motherwort aqueous ethanol extract may effectively inhibit the proliferation of breast cancer cells through mechanisms of both cytotoxicity and cell cycle arrest. The cellular effects of MAEE are non-apoptotic and ER independent on breast cancer cells.  相似文献   
995.
Inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis are chronic enteropathies that probably result from a dysregulated mucosal immune response. These pathologies are characterized by oxidative and nitrosative stress, leukocyte infiltration and up-regulation of pro-inflammatory substances. Current IBD treatment presents limitations in both efficacy and safety that stimulated the search for new active compounds. Garcinia cambogia extract has attracted interest due to its pharmacological properties, including gastroprotective effects. In this study, the antiinflammatory activity of a garcinia extract was assessed in TNBS-induced colitis rats. The results obtained revealed that garcinia administration to colitic rats significantly improved the macroscopic damage and caused substantial reductions in increases in MPO activity, COX-2 and iNOS expression. In addition, garcinia extract treatment was able to reduce PGE(2) and IL-1beta colonic levels. These antiinflammatory actions could be related to a reduction in DNA damage in isolated colonocytes, observed with the comet assay. Finally, garcinia extract caused neither mortality nor toxicity signals after oral administration. As such, the antiinflammatory effects provided by the Garcinia cambogia extract result in an improvement of several parameters analysed in experimental colitis and could provide a source for the search for new antiinflammatory compounds useful in IBD treatment.  相似文献   
996.
钙池操纵的Ca~(2 )通道(store-operated Ca~(2 ) channels,SOC)是非兴奋细胞Ca~(2 )内流的主要通道之一,参与多种病理和生理过程,在钙信号通路的研究中,SOC的激活机制一直是人们关注的焦点之一,迄今为止,钙内流因子模型(Ca~(2 ) innux factor model,CIF model)和构象耦联模型fconformational coupling model)受到广泛关注.部分学者已经从很多不同类型的细胞中提取出CIF,并证实钙非依赖性的磷脂酶A_2(Ca~(2 )-independent phospholipase A_2,iPLA_2)作为CIF的底物,在某些类型细胞的SOC激活过程中发挥重要作用,并进一步提出了ER- CIF-iPLA_2-CaM-LysoPLs-SOC通路模型.瞬时受体电位(transient receptor potential,TRP)通道蛋白与1.4,5-磷酸肌醇受体(inositol 1,4,5 trisphosphate receptor,IP_3R)的结构连接作为构象耦联模型的基础已被广泛证实,随着对IP_3R,Ryanodine受体、肌动蛋白等在钙信号通路中所发挥作用的深入研究,构象耦联模型将得到不断补充和完善.SOC激活机制的破解,将对进一步完善非兴奋细胞的钙通道特性及其调节机制理论带来重大突破.  相似文献   
997.
BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) effectively treat various anxiety disorders, although symptoms of anxiety are often exacerbated during early stages of treatment. We previously reported that acute treatment with the SSRI citalopram enhances the acquisition of auditory fear conditioning, which is consistent with the initial anxiogenic effects reported clinically. Here, we extend our findings by assessing the effects of acute SSRI treatment on the expression of previously acquired conditioned fear. METHODS: Rats underwent fear conditioning drug-free. Tone-evoked fear responses were tested after drug treatment the following day. This protocol more closely resembles the clinical setting than pre-conditioning treatment, because it evaluates effects of treatment on a pre-existing fear rather than on the formation of a new fear memory. RESULTS: A single pre-testing injection of the SSRIs citalopram or fluoxetine significantly increased fear expression. There was no effect of the antidepressant tianeptine or the norepinephrine reuptake inhibitor tomoxetine, indicating that this effect is specific to SSRIs. The SSRI-induced enhancement in fear expression was not blocked by tropisetron, a 5-HT(3) receptor antagonist, but was blocked by SB 242084, a specific 5-HT(2C) receptor antagonist. CONCLUSIONS: Enhanced activation of 5-HT(2C) receptors might be a mechanism for the anxiogenic effects of SSRIs observed initially during treatment.  相似文献   
998.
复方通络中药改善肥胖患者血管内皮细胞功能障碍研究   总被引:1,自引:0,他引:1  
目的观察复方通络中药对单纯性肥胖患者血管内皮依赖性舒张功能障碍的干预效应,探讨其作用机制。方法应用高分辨血管超声检查选择血管内皮依赖性舒张功能障碍[以血流介导的肱动脉扩张率(FMD)表示]肥胖患者(65例),随机分为通络中药治疗组和对照组。治疗组32例,对照组33例。治疗组给予辛香疏络2号胶囊,3g/次,每日3次;对照组给予淀粉胶囊,3g/次,每日3次。共用药12周,分别测定用药前后FMD、肱动脉内径(D0),同时检测辛香疏络2号治疗前后患者血清总胆固醇(TC)、三酰甘油(TG)的变化。结果治疗后治疗组FMD较对照组明显增加(P〈0.01),TC、TG较治疗前及对照组明显下降(P〈0.01)。结论复方通络中药辛香疏络2号胶囊可明显改善肥胖患者血管内皮障碍,调节血脂可能是其改善血管内皮功能机制之一。  相似文献   
999.
AIMS: To characterize the determinants of diabetes-related emotional distress by treatment modality (diet only, oral medication only, or insulin). METHODS: A total of 815 primary care patients with Type 2 diabetes completed the Problem Areas in Diabetes (PAID) Scale and other questions. We linked survey data to a diabetes clinical research database and used linear regression models to assess the associations of treatment with PAID score. RESULTS: PAID scores were significantly higher among insulin-treated (24.6) compared with oral-treated (17.8, P < 0.001) or diet-treated patients (14.7, P < 0.001), but not different between oral- vs. diet-treated patients (P = 0.2). Group scores remained similar, but the statistical significance of their differences was reduced and ultimately eliminated after sequential adjustment for diabetes severity, HbA(1c), body mass index, regimen adherence, and self-blood-glucose monitoring. Insulin-treated patients reported significantly higher distress than oral- or diet-treated patients on 16 of 20 PAID items. 'Worrying about the future' and 'guilt/anxiety when ... off track with diabetes' were the top two serious problems (PAID >or= 5) in all treatment groups. Not accepting diabetes diagnosis was a top concern for oral- and diet-treated patients, and unclear management goals distressed diet-treated patients. CONCLUSIONS: Primary care patients treated with insulin reported higher diabetes-related emotional distress compared with oral- or diet-treated patients. Greater distress was largely explained by greater disease severity and self-care burdens. To improve diabetes-specific quality of life, clinicians should address patients' sense of worry and guilt, uncertain acceptance of diabetes diagnosis, and unclear treatment goals.  相似文献   
1000.
目的用缺氧方法制备的肺源性心脏病(肺心病)大鼠为对象,研究肺心病中M2和β1受体抗体的含量及其与疾病的关系。方法选取健康雄性Wistar大鼠36只,随机分为3组:单纯缺氧组,缺氧加注射FeCl3组,健康对照组。SA-酶联免疫吸附测定(ELISA)法检测血清M2和β1受体抗体变化。最后处死大鼠观察心脏指标,并分析它与抗体滴度的相关性。结果血清中M2和β1受体抗体随缺氧时间延长而升高,滴度分别到第3周达高峰M2受体抗体为1∶80(单纯缺氧组)和1∶53(缺氧加注射FeCl3组),β1受体抗体为1∶60(单纯缺氧组)和1∶45(缺氧加注射FeCl3组),并且P/N值从第2周开始有阳性意义,到第3周同样达高峰M2和β1受体抗体分别为2.88(单纯缺氧组)、2.76(缺氧加注射FeCl3组)和3.25(单纯缺氧组)、3.99(缺氧加注射FeCl3组)。而肺心病大鼠心脏指标最终改变为R/(L+S)0.333±0.027(单纯缺氧组),0.348±0.033(缺氧加注射FeCl3组),R/BW×10-30.58±0.13(单纯缺氧组),0.60±0.15(缺氧加注射FeCl3组),(L+S)/BW×10-32.000±0.024(单纯缺氧组),2.081±0.037(缺氧加注射FeCl3组),并且抗体滴度与心脏改变呈正相关。结论M2和β1受体抗体阳性率及抗体滴度在大鼠肺心病模型中明显增高,表明肺心病的发生发展与M2和β1受体的自身抗体密切相关。  相似文献   
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