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991.
氧化苦参碱防治半乳糖胺诱导大鼠肝纤维化的实验研究 总被引:53,自引:1,他引:53
目的 观察氧化苫参碱(oxymatrine,OM)预防及治疗大鼠肝纤维化的疗效并探讨其作用机制。方法 采用半乳糖胺诱导的大鼠肝纤维化模型,观察OM(90mg/kg)干预前后血及肝组织生物化学、羟脯氨酸含量、TGF β_1 mRNA表达水平及病理组织学改变。结果 OM干预组肝组织羟脯氨酸含量 (μg/mg)较模型组显著下降(预防观察组为0.50±0.11和0.99±0.14,t=8.366,P<0.01;治疗观察组为0.44±0.04和0.70±0.06,t=9.839,P<0.01);与模型组比较,干预组血清ALT、AST亦显著下降(P<0.01);病理组织学显示干预组较模型组 Ⅰ、Ⅲ型胶原沉积减少,纤维间隔纤细,数量减少;干预织肝组织匀浆内超氧化物歧化酶活性(NU/mg)较模型组升高(预防观察组为149.81±15.28和95.22±16.33,t=7.309,P<0.01;治疗观察组为157.68±19.54和119.88±14.94,t=4.348,P<0.01), 而丙二醛(nmol/mg)低于模型组(预防观察组为2.06±0.17和4.57±0.37,t=17.529,P<0.01;治疗观察组为1.76±0.24和3.10±0.17,t=12.697,P<0.01);PT-PCR显示干预组TGF β_1 mRNA表达水平降低(预防观察组为0.21±0.01和0.50±0.01,t-48.665,P<0.01;治疗观察组为0.18±0.02和0.38±0.01,t=22.464,P<0.01)。结论 氧化苫参碱对半乳糖胺诱导的肝纤维化有预防及治疗作用,其部分机制为通过 相似文献
992.
兔肝Vx-2移植癌模型建立方法的比较 总被引:4,自引:0,他引:4
一、材料与方法 1.材料:60只新西兰白兔,体重2.5~2.7kg/只,雌雄各半,由第四军医大学实验动物中心提供。兔Vx—2癌株由唐都医院段云友教授惠赠,癌株种类为Vx—2鳞状细胞癌。大功率DSA X线机(德国Siemens公司生产)。 2、方法:(1)Vx—2瘤细胞按一般法培养、传代,台盼蓝染色,活细胞计数,用培养液凋制成5 ×107个/ml活细胞。(2)将新西兰兔随机分为A、B、C三个处理组,每组20只。A组:胃肝动脉注入瘤细胞(浓度 5× 107个/ml)悬液 1.0 ml/只。B组:经肝包膜注入… 相似文献
993.
Relationship between the imaging features and pathologic alteration in hepatoma of rats 总被引:8,自引:0,他引:8
Yang JH You TG Li N Qian QJ Wang P Yan ZL Wu MC 《World journal of gastroenterology : WJG》2003,9(1):69-72
AIM: The imaging features of MRI and DSA, using the models of implanted and induced hepatoma, were investigated in rats. METHODS: CBRH3 cancer cells were implanted for different liver site of rat liver and the diethylnitrosoamine was given orally to rats in order to induce liver cancer. Both experimental groups were detected by magnetic resonance imaging (MRI), digital subtraction angiography (DSA) and morphologic assay. RESULTS: Hypointensity on T1WI and homogenous high signal intensity on T2WI in MRI, and ring-like abnormal stain on DSA were found in implanted cancer. Induced cancers appeared as homogeneous or heterogeneous hypointensity on T1WI (10 cases), and equal or slight high intensity on T2WI (8 cases), but some as hypointensity on T2WI (2 cases). CONCLUSION: The imaging features of implanted cancers were similar to that of human liver metastases. Therefore, it could serve as an experimental model of human liver metastatic tumor. The imaging feature of induced cancers, whereas, were similar to that of human primary liver cancer. It could be use as an experimental model of human primary liver cancer. 相似文献
994.
A mouse model of severe acute pancreatitis induced with caerulein and lipopolysaccharide 总被引:7,自引:1,他引:7
AIM: To establish a non-traumatic, easy to induce and reproducible mouse model of severe acute pancreatitis (SAP)induced with caerulein and lipopolyasccharide (LPS).METHODS: Thirty-two healthy mature NIH female mice were selected and divided at random into four groups (each of 8 mice), i.e., the control group (NS group), the caerulein group (Ch group), the lipopolysaccharide group (LPS group),and the caerulein+LPS group (Cn+LPS group). Mice were injected intraperitoneally with caerulein only, or LPS only,and caerulein and LPS in combination. All the animals were then killed by neck dislocation three hours after the last intraperitoneal injection. The pancreas and exo-pancreatic organs were then carefully removed for microscopic examination. And the pancreatic acinus was further observed under transmission electron microscope (TEM). Pancreatic weight, serum amylase, serum nitric oxide (NO)concentration, superoxide dismutase (SOD) and malondialdehyde (MDA) concentration of the pancreas were assayed respectively.RESULTS: (1) NS animals displayed normal pancreatic structure both in the exocrine and endocrine. In the LPS group, the pancreas was slightly edematous, with the infiltration of a few inflammatory cells and the necrosis of the adjacent fat tissues. All the animals of the Cn group showed distinct signs of a mild edematous pancreatitis characterized by interstitial edema, infiltration of neutrophil and mononuclear cells, but without obvious parenchyma necrosis and hemorrhage. In contrast, the Cn+LPS groupshowed more diffuse focal areas of nonviable pancreatic and hemorrhage as well as systemic organ dysfunction.According to Schmidt's criteria, the pancreatic histologic score showed that there existed significant difference in the Cn+LPS group in the interstitial edema, inflammatory infiltration,parenchyma necrosis and parenchyma homorrhage in comparison with those of the Cn group, LPS group and NS group (P<0.01 or P<0.05). (2) The ultrasturcture of acinar cells was seriously damaged in the Cn+LPS group. Chromatin margination of nuclei was present, the number and volume of vacuoles greatly increased. Zymogen granules (ZGs) were greatly decreased in number and endoplasmic reticulum exhibited whorls. The swollen mitochondria appeared, the crista of which was decreased in number or disappeared.(3) Pancreatic weight and serum amylase levels in the Cn +LPS was significantly higher than those of the NS group and the LPS group respectively (P<0.01 or P<0.05).However, the pancreatic wet weight and serum amylase concentration showed no significant difference between the Cn+LPS group and the Cn group. (4) NO concentration in the Cn+LPS group was significantly higher than that of NS group, LPS group and Cn group(P<0.05 or P<0.01). 5) The SOD and MDA concentration of the pancreas in the Cn+LPS group were significantly higher than those of NS, LPS and Cn groups (P<0.05 or P<0.01).CONCLUSION: The mouse model of severe acute pancreatitis could be induced with caerulein and LPS, which could be non-traumatic and easy to induce, reproducible with the same pathological characteristics as those of SAP in human, and could be used in the research on the mechanism of human SAP. 相似文献
995.
Establishment of transgenic mice carrying the gene of human nuclear receptor NR5A2 (hB1F) 总被引:4,自引:0,他引:4
Wang SL Yang H Xie YH Wang Y Li JZ Wang L Wang ZG Fu JL 《World journal of gastroenterology : WJG》2003,9(6):1333-1336
AIM: Human hepatitis B virus enhancer II B1 binding factor (hB1F) was cloned and characterized as a novel member of the Ftz-F1 (NR5A) nuclear receptor subfamily. Although progresses have recently been made, its biological function remains largely unidentified. The aim of this study was to establish an hB1F transgenic mouse model to promote the functional study of hB1F. METHODS: Transgene fragments were microinjected into fertilized eggs of mice. The manipulated embryos were transferred into the oviducts of pseudopregnant female mice. The offsprings were identified by PCR and Southern blot analysis. Transgene expression was analyzed with RT-PCR and Western blot analysis. Transgenic founder mice were used to establish transgenic mouse lineages. The F1 and F2 mice were identified by PCR analysis. RESULTS: Seven mice were identified as carrying copies of transgene. RT-PCR and Western blotting results showed that the transgene was expressed in heart, liver, lung, kidney and stomach in one of the transgenic mouse lineages. Genetic analysis of the transgenic mice demonstrated that the transgene was integrated into the chromosome at a single site, and was transmitted stably. CONCLUSION: In this study we established an hB1F transgenic mouse model, which will facilitate the investigation of the biological function of hB1F in vivo. 相似文献
996.
骨膜剥离加髓腔破坏建立股骨头坏死模型的可行性研究 总被引:1,自引:0,他引:1
目的探讨骨膜剥离加髓腔破坏建立股骨头坏死(ONFH)动物模型的可行性。方法成年杂种狗12只(13~17kg),手术剥离其左侧股骨近端约4cm范围内的全部骨膜及周围组织,并于股骨颈中下1/3处用直径1mm的钻头钻孔,破坏此处髓腔松质骨成分,皮质骨保持完整;右侧做正常对照。采用股动脉数字减影血管造影(DSA)技术检测、比较手术前后股骨头局部的血液循环变化,并分别于术后1、4、8和16周获取股骨头标本,行病理切片检查。结果术后DSA图像显示髋关节局部出现多量新生血管由股骨颈、髓内等处再生进入有坏死改变的股骨头内。四组实验侧股骨头均出现不同程度ONFH表现,第16周股骨头标本示轮廓改变,轻度塌陷外观。结论骨膜剥离加髓腔破坏法能成功建立ONFH模型,可用于ONFH的发生、发展机制及治疗的研究。 相似文献
997.
目的:建立兔髂动脉球囊损伤模型,观察粒细胞-巨噬细胞集落刺激因子(granulocyte-macrophagecolony-stimulatingfactor,GM-CSF)对血管损伤后内膜增生及机体凝血纤溶功能的影响。方法:健康新西兰雄性大白兔24只,随机分为GM-CSF组和对照组。GM-CSF组皮下注射GM-CSF10μg·kg-1·d-1,对照组皮下注射同等量生理盐水。7d后球囊扩张损伤一侧髂动脉。术后4周处死动物,采集标本,观察内膜增生情况;分别于术前、术后1周,2周,4周耳缘静脉采血检测一氧化氮(NO)浓度、组织型纤溶酶原激活剂(tissue-typeplasminogenactivator,t-PA)活性和纤溶酶原激活物抑制剂-1(plasminogenactivatorinhibitor-1,PAI-1)活性。结果:术后4周病理组织学见GM-CSF组内膜增生程度较对照组明显减轻,新生内膜中血管平滑肌细胞和纤维组织较对照组明显减少,内皮较完整、光滑,管腔狭窄程度较轻。GM-CSF组术后2周,4周NO浓度明显高于对照组[(91·9±11·6)μmol/Lvs(81·7±12·2)μmol/L];[(97·7±10·1)μmol/Lvs(83·2±12·6)μmol/L];术后1周,2周,4周t-PA活性2组均高于术前,但2组间差异无统计学意义;2组术前、术后PAI-1活性差异无显著性,2组间亦差异无显著性。结论:GM-CSF能促进损伤内膜修复,恢复正常内皮功能,且并未诱导球囊损伤动物机体的高凝状态。 相似文献
998.
自制气动左心辅助泵对急性左心室心力衰竭犬血浆CT-1及BNP的影响 总被引:3,自引:0,他引:3
目的:通过监测血流动力学及测量血浆心肌营养素-1(CT-1)、脑钠肽(BNP)浓度的变化,观察自制气动左心辅助泵对急性左心衰竭实验犬左心功能的影响。方法:18只实验犬建立犬心力衰竭(心衰)模型后,随机分为2组:辅助组(A组)、对照组(B组)。从术前到术后360min共4个时间点内监测血流动力学变化,并测定血浆CT-1和BNP浓度。结果:急性左心衰竭前各组CT-1与BNP水平差异无显著性(P>0·05)。心衰后360min辅助组CT-1和BNP水平分别是(44·2±4·5)pg/mL和(58·5±6·9)pg/mL,而对照组分别为(180·6±5·7)pg/mL和(132·9±3·6)pg/mL,2组差异有显著性(P<0·01)。结论:血流动力学及血浆CT-1与BNP的变化表明,自制气动左心辅助泵能明显改善急性左心衰实验犬的左心功能。 相似文献
999.
动物实验对促进新药研发和明确药理机制具有重要意义,随着中医药现代化发展,病证结合动物实验被越来越多的学者广泛应用,动物模型的构建与评价体系也在逐步完善。脾胃系疾病发病率高,不易治愈,中医药治疗脾胃病具有独特优势,为深入研究中医中药治疗脾胃病的分子机制及药效效果,制备其相关的病证结合动物模型意义重大。单纯西医疾病模型具有一定局限性,病证结合动物模型符合中医辨证论治原则,对脾胃病的病机阐明和新药研发尤为重要。因此,笔者通过对常见脾胃病病证结合动物模型各证候的构建方法和评价系统进行归纳总结,阐述脾胃病病证结合动物模型的发展概况和建立特点,以期解决动物实验模型病证评价指标的关键问题,完善病证造模与测量标准,为研究人员提供参考依据,推动中医药治疗脾胃病进一步发展。 相似文献
1000.
肌少症是与增龄相关的肌肉质量减少和功能减退,其增加了摔倒、骨折、死亡及住院等风险,严重威胁老年人健康。构建动物模型是开展肌少症发病机制、临床干预及治疗方案设计研究的基础。由于肌少症表型的复杂性,使得选择合适的造模方法、构建恰当的动物模型至关重要。本文综述了近年来肌少症动物模型造模方法的相关进展,为开展肌少症发病机制、预防、治疗等相关研究提供参考。 相似文献