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51.
车前子对高脂血症大鼠脂质过氧化的影响 总被引:21,自引:1,他引:20
目的 : 探讨车前子对高脂血症大鼠脂质过氧化的影响。方法 : 采用大鼠血清及多脏器组织 ,观察车前子对高脂血症大鼠脂质过氧化的影响。结果 : 高脂对照组血清和心肌超氧化物歧化酶 ( SOD)活性显著降低 ,而脂质过氧化物 ( LPO)含量明显升高 ,血清和肝脏的过氧化氢酶( CAT)、谷胱苷肽过氧化物酶 ( GSH-Px)活性明显降低。补充车前子后显著升高血清及心肌组织SOD活性 2 2 %和 2 8% ,以及肝脏 GSH-Px活性 2 2 %。而使血清及心肌的 LPO含量分别下降 3 2 %和 1 7%。结论 : 1 5 g/kg车前子可提高高脂血症大鼠体内抗氧化能力并免受自由基损伤 相似文献
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Langerhans cells (LCs) in the normal cervix (control, 19 cases), cervical carcinoma in situ( CIS, 19 cases) and invasive cervical carcinoma (30 cases), interdigitatlng cells (IDCs) and follicular dendritic cells (FDCs) in obturator lymph node draining Invasive cervical carcinoma were quantitatively assessed by ABC immunohistochemical staining using anti-S100 protein antibody. The results indicated that S100 LCs in sltu, S100 IDCs and S100 FDCs In obturator lymph node showed dendritic features with a specific distribution. Number of LCs in situ in Invasive carcinoma increased significantly when compared with CIS and control groups. There was no change in LCs number between grade Ⅱ and Ⅲ of squemous cell carcinoma. Number of IDCs was significantly less in stage Ⅱ than in stage Ⅰ . FDCs number In different Invasive depthes and clinical stages showed no obvious change. The results suggest that progression of cervical carcinoma is closely related to decrease of LCs hi situ and IDCs in regional lymph n 相似文献
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在微量注射大量肝脏mRNA之后,通过电压箝方法进行功能鉴定,两栖类卵母细胞成功地表达了AVPV1a受体。但在灌流AV4-8溶液时,却不能诱导卵母细胞产生内向振荡电流反应。提示AVP4-8不能通过AVPV1a受体而介导生理学效应。 相似文献
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中期因子和微血管密度在乳腺癌中的表达 总被引:8,自引:0,他引:8
目的 探讨中期因子 (MK)与微血管密度 (MVD)的表达与乳腺癌生物学行为的关系及对预后的意义。方法 采用免疫组织化学方法检测 67例乳腺浸润性导管癌组织MK、MVD表达水平 ,并对其与乳腺癌临床病理特征的关系进行统计学分析。结果 本组 67例中 ,MK阳性表达者 3 7例 ,占 5 5 .2 %。MK表达水平及MVD值均与肿块大小 ,腋淋巴结状态及复发和转移有关。MK表达阳性者的MVD均值 (90 .75± 3 3 .0 5 )明显高于MK表达阴性组 (70 .48± 3 1.3 3 ,P <0 .0 1)。结论 MK在乳腺癌血管生成中发挥重要作用 ,MK的阳性表达与乳腺癌的发生、发展和预后密切相关 ,可作为一种有价值的肿瘤标志和预后指标。 相似文献
57.
目的:探讨邻苯二甲酸二乙基己酯(DEHP)对新生小鼠睾丸及Leyd ig细胞形态结构及功能的影响。方法:DEHP分别以低、中、高3组剂量[100、200、500 mg/(kg.d)]灌胃作用于怀孕12 d到产后3 d(GD12~PND3)的KM母鼠,观察DEHP对新生雄性仔鼠体重、睾丸重量、Leyd ig细胞形态结构和3β-羟基类固醇脱氢酶(3-βHSD)活性、酶反应面积的影响。结果:DEHP作用于母鼠后,其雄性子代幼鼠体重和睾丸重量减轻,睾丸Leyd ig细胞形态、超微结构发生改变;高剂量组Leyd ig细胞数量明显增多;低、中剂量组睾酮合成关键酶3β-HSD酶活性下降,酶反应面积减小,但高剂量组在仔鼠出生后15 d时酶活性降低[(吸光度值(0.154±0.011)vs空白对照组(0.222±0.013),P<0.01],而酶反应面积增大[(6 303.0±745.6)μm2vs空白对照组(5 091.4±214.4)μm2,P<0.01)]。结论:DEHP能影响新生雄性小鼠体重、睾丸重量、Leyd ig细胞的形态结构和3β-HSD活性,具有抗雄激素效应。 相似文献
58.
目的:探讨血管内皮生长因子在肺癌中的表达情况与肺癌病理生物学行为之间的关系。方法:采用免疫组化SP法检测47例肺癌组织和10正常肺组织中VEGF的表达水平。结果:肺癌组织中VEGF的表达明显高于正常肺组织(P<0.005),P53、VEGF表达与肺癌的分化程度、淋巴结转移及P—TNM分期密切相关(P<0.05),与患者的性别、年龄、肿瘤大小及组织类型无关(P>0.05)。结论:检测肺癌组织中VEGF的表达水平有助于了解肿瘤的生物学行为,并可作为判断其预后的有价值指标。 相似文献
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With the development of interventional therapy, it is necessary for evaluating cerebral vessels to instruct treatment and determine prognosis of patients with ischemic stroke; however, correlation of distribution of infarction focus and clinical symptoms with degrees of cerebrovasoular stricture is still unclear.OBJECTIVE: To evaluate the characteristics of cerebral arterial stricture of patients with ischemic stroke with transcranial Doppler (TCD) and color duplex flow imaging (CDFI) and compare the correlation between distribution of cerebral infarction focus and clinical types with magnetic resonance imaging (MRI).DESIGN: Contrast observation.SETTING: Department of Neurology, the First Hospital of Jilin University.PARTICIPANTS: A total of 159 patients with ischemic stroke were selected from the Department of Neurology, the First Hospital of Jilin University from January to December 2005, including 106 males and 53 females aged from 27 to 88 years. Bases on diagnostic criteria of cerebrovascular disease established by Rao et al, clinical manifestations of all patients were evaluated with CT or nuclear magnetic resonance. All patients provided the confirmed consent.METHODS: The accepted patients received TCD and CDFI examination at 1 week after onset of ischemic stroke. Among them, 112 patients received cerebrovascular imaging examination simultaneously. MRI was used to check cerebral infarction focus and cerebrovascular stricture > 50% was regarded as the accepted vessels. In addition, DWI-T2 TCD (Germany) was used to check middle cerebral artery, and degrees of middle cerebral artery were classified into mild, moderate and severe stricture based on blood velocity (140 cm/s,180 cm/s). Stroke was classified based on characteristics of infarction focus and clinical symptoms showed with MRI and correlation with degrees of cerebrovascular stricture was analyzed simultaneously.MAIN OUTCOME MEASURES: Correlation between the characteristics of ischemic stroke and clinical symptoms checked with TCD and CDFI.RESULTS: A total of 159 patients with ischemic stroke were involved in the final analysis; in addition, 112 oases received cerebrovascular imaging examination simultaneously. ① MRI results of 159 patients with cerebral artery occlusive disease (CAOD): There were 131 patients (82.3%) with cerebral infarction, 40 (25.2%)with transient ischemic attack and 4 (2.5%) with subclavian steal syndrome (SSS). ② Infarction types with MRI examination: There were 33 patients (20.8%) with solitary cerebral infarction and 98 (61.6%) with multiple-cerebral infarction. ③ Results of TCD, CDFI, MRI angiography, CT angiography and digital subtraction angiography (DSA): Among 112 patients, 181 lesion sites (61 .8%) were located in cranium and 112 lesion sites were located out of cranium; especially, lesion site was mostly observed in stem of middle cerebral artery (31.2%) and watershed of basilar artery (7.2%) in cranium and the beginning site of internal carotid artery (21 .4%) out of cranium. ④ Correlation of vascular stricture checking with TCD, MRI and clinical diagnosis: On one hand, MRI and clinical diagnosis demonstrated that 68 patients had a watershed infarction; meanwhile,TCD examination indicated that there were 3 patients with mild vascular stricture, 24 with moderate vascular stricture and 36 with severe vascular stricture. On the other hand, among 68 patients with non-watershed infarction, there were 27 patient with mild vascular stricture, 26 with moderate vascular stricture and 15 with severe vascular stricture. There were significant differences (x2 =26.854, P =0.001 ). Clinical diagnosis indicated that 40 patients had transient ischemic attack and TCD examination demonstrated that there were 8 patient with mild vascular stricture, 12 with moderate vascular stricture and 20 with severe vascular stricture. There were significant differences as compared with 68 patients with watershed infarction (x2 =21.258, P =0.001). ⑤Correlation of vascular stricture checking with CDFI, MRI and clinical diagnosis: On one hand, among patients who were determined as watershed infarction with MRI and clinical diagnosis, CDFI examination indicated that there were 32 patients with mild vascular stricture at neck, 25 with moderate vascular stricture and 6 with severe vascular stricture. On the other hand, among patients with non-watershed infarction, there were 48 patient with mild vascular stricture, 18 with moderate vascular stricture and 2 with severe vascular stricture.There were significant differences (x2 =6.018, P =0.019). Among patients with transient ischemic attack checking with clinical diagnosis, there were 23 patient with mild vascular stricture, 9 with moderate vascular stricture and 8 with severe vascular stricture. There were no significant differences as compared with patients with non-watershed infarction (x2 =0.597, P=0.440).CONCLUSION: ① TCD and CDFI are effective marks to determine cerebral arterial stricture and hemodynamical changes. ② Infarction and transient ischemic attack at watershed are generally clinical phenotypes of CAOD patients and infarction at watershed is correlated with degrees of cerebrovascular stricture.③ TCD, MRI and clinical analysis of stroke types are significant for instructing treatment and evaluate prognosis. 相似文献