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91.
Bilateral six-hydroxydopamine (6-OHDA) lesions were placed in the amygdala of rats self-administering cocaine (1.5 mg/kg per injection i.v.) under a progressive ratio schedule of reinforcement. Post-lesion access to three doses of cocaine (1.5, 0.75 and 0.37 mg/kg per injection i.v.) revealed a lesion effect only at the highest dose. At this dose, the lesion caused a significant increase in breaking point. No change in the breaking point was produced at the lower two doses. The biochemical results show a significant reduction in dopamine and DOPAC levels within the amygdala and an increase in dopamine within the NACC. In contrast, noradrenaline and serotonin (5-HT) levels were unaffected by the lesion in any of the dissected areas. These results demonstrate that no specific effect on cocaine reinforcement was produced by 6-OHDA lesions of the amygdala. The possibility that the lesion may have attenuated the anxiogenic qualities of the high dose of cocaine is discussed.  相似文献   
92.
目的:研究肝细胞癌(hepatocellular carcinoma,HCC)经导管肝动脉化疗栓塞(transcatheter arterial chemoemboli-zation,TACE)后残癌组织细胞黏附分子CD44v6和ICAM-1(intercelluar adhesion molecule-1,ICAM-1)的表达情况。方法:经病理证实的HCC 50例,包括单纯手术切除30例(对照组),TACE术后行Ⅱ期手术切除20例(TACE组)。TACE组患者术前接受1~2次不等的TACE治疗,均按统一规范标准给予化疗药物灌注+栓塞治疗。对标本行免疫组织化学PV-9000染色,其中TACE组取病灶边缘残存肿瘤部分,检测肿瘤组织CD44v6和ICAM-1的表达,将两组结果进行对照分析。结果:对照组和TACE组CD44v6和ICAM-1均有不同程度的表达。对照组CD44v6表达阳性22例(22/30,73.33%),TACE组CD44v6表达阳性13例(13/20,65%),两者间无显著性差异(P>0.05);对照组ICAM-1表达阳性19例(19/30,63.33%),TACE组ICAM-1表达阳性12例(12/20,60%),两者间亦无显著性差异(P>0.05)。对照组和TACE组中CD44v6和ICAM-1表达间均呈正相关(P<0.05)。结论:TACE术后残癌组织CD44v6和ICAM-1仍有较高的表达,TACE并不能有效降低肝癌组织CD44v6和ICAM-1的表达;两者表达呈正相关。  相似文献   
93.
[目的]检测兔肢体爆炸伤创面组织IL-1、IL-6、TNF-α和CRP含量。[方法]新西兰大白兔24只,随机分为炸伤后即刻取材组(A组,n=12)和炸后1h取材组(B组,n=12);0.9g铜壳单质猛黑索金炸药(RDX)以海绵间隔5cm,绑于左下肢股部中段前外侧,电引爆,分别取爆炸中心区(Ⅰ区)、爆炸边缘区(Ⅱ区)、爆震区(Ⅲ区)的肌肉组织,测IL-1、IL-6、TNF-α、CRP的含量并取对侧肢体肌肉组织做对照研究。[结果]炸伤后两组各区标本IL-1、IL-6、TNF-α、CRP含量均比正常组织高,差异显著(P〈0.05),且从Ⅰ区、Ⅱ区到Ⅲ区,含量依次降低,差异显著(P〈0.05):A组:Ⅱ区与Ⅲ区的IL-1含量差别有显著意义(P〈0.05)。Ⅰ区与Ⅲ区、Ⅱ区与Ⅲ区的IL-6含量差别有极显著意义(P〈0.01)。Ⅰ区与Ⅲ区的TNF-α、CRP含量差别有极显著意义(P〈0.01),Ⅰ区与Ⅱ区、Ⅱ区与Ⅲ区的含量差别有显著意义(P〈0.05)。其余各区的含量无统计学差异(P〉0.05);B组:Ⅱ区与Ⅲ区的Ⅱ-1、IL-6、TNF-α含量差别有显著意义(P〈0.05)。Ⅰ区与Ⅲ区、Ⅰ区与Ⅱ区、Ⅱ区与Ⅲ区的CRP含量差别有显著意义(P〈0.05)。其余各区的含量无统计学差异(P〉0.05)。A、B两组比较,炸后组织中上述因子表达虽有增强,但差异无显著意义(P〉0.05)。[结论]肢体爆炸伤1h内,创面组织中IL-1、IL-6、TNF-α、CRP表达增强,不同区域间表达有差异。  相似文献   
94.
目的 探讨ApoE-/-小鼠肾动脉粥样硬化斑块破裂对下游肾脏的损伤机制。 方法 采用ApoE-/-小鼠建立粥样硬化性肾动脉狭窄(ARAS)动物模型。选择肾动脉狭窄程度 <50%的ApoE-/-小鼠,按斑块分为破裂组和未破裂组;选择同条件喂养的C57BL/6J 野生型小鼠为对照组。常规检测Scr及尿 N-乙酰-β-氨基葡萄糖苷酶(NAG)活性;Western印迹检测细胞核中核转录因子κBp65(NF-κBp65)、细胞间黏附分子1(ICAM-1)及P-选择素(P-sel)表达; RT-PCR检测白细胞介素6 (IL-6)mRNA表达;免疫组化染色检测巨噬细胞浸润情况。 结果破裂组Scr和尿NAG活性明显升高(均P < 0.01);肾组织出现病理改变,肾间质中巨噬细胞浸润增加(P < 0.05);细胞核中NF-κBp65表达增加(P < 0.05);ICAM-1、P-sel、IL-6 mRNA表达增加(P < 0.05)。未破裂组上述指标与对照组比较,差异无统计学意义(P > 0.05);肾脏未见明显病理改变。 结论 肾动脉粥样硬化斑块破裂可引起肾脏病理改变和肾功能受损;在粥样硬化性肾动脉狭窄的肾损害机制中,炎性反应是重要因素之一。  相似文献   
95.
重组人白细胞介素6对SW872脂肪细胞增殖和凋亡的影响   总被引:4,自引:4,他引:0  
目的 探讨白细胞介素 6(IL 6)对SW872脂肪细胞增殖及凋亡的影响。方法 体外培养SW872脂肪细胞 ,0 .6mmol/L油酸诱导SW872前脂肪细胞分化 ,化学比色法检测细胞内三酰甘油的总量 ;油红O染色观察细胞内脂肪的聚积 ;MTT法检测不同浓度IL 6对SW872前脂肪细胞增殖活力的影响 ;流式细胞仪分析IL 6对SW872成熟脂肪细胞凋亡的影响。结果  0 .6mmol/L油酸刺激 72h ,几乎 10 0 %SW872前脂肪细胞分化为成熟的脂肪细胞 ,细胞内三酰甘油的含量明显增加 ,油红O染色胞浆内可见丰富的脂滴 ;5 μg/LIL 6对SW872前脂肪细胞的增殖没有影响 ,10~ 5 0 μg/LIL 6明显抑制SW872前脂肪细胞的增殖 ;IL 6对SW872成熟脂肪细胞的凋亡无影响。结论 IL 6能明显抑制SW872前脂肪细胞的增殖 ,其抑制效应呈剂量依赖性 ,表明IL 6可能与肥胖有关 ,高剂量IL 6可降低肥胖的程度。  相似文献   
96.
BACKGROUND: Although there is increasing evidence suggesting that the vagus nerve functions as a connector between the nervous and immune systems in animals, little is known about the role of the vagus nerve in postoperative acute phase response in humans. MATERIALS AND METHODS: The extent of fever and acute phase protein response and the production of inflammatory cytokine during the early postoperative period were compared among the patients who had undergone total gastrectomy including truncal vagotomy (n = 13), those having distal gastrectomy with division of vagal branches (n = 14), and the patients with vagal nerve preserving gastrectomy (n = 12). RESULTS: There was no significant difference in serum levels of C-reactive protein, alpha-1-antirypsin, and interleukin-6 among the three groups. Also, postoperative maximum body temperature was similar. CONCLUSIONS: Vagotomy did not influence acute phase response after gastric cancer surgery. A multipathway mechanism for acute phase response including the induction of fever is suggested.  相似文献   
97.
目的:通过对相同长度、宽度、不同厚度的Ti-6Al-7Nb合金铸件挠度的测量,观察铸件厚度与挠度的关系,为确定Ti-6Al-7Nb合金铸造义齿基托的适合厚度提供实验依据。方法:参照ISO关于义齿基托材料挠度的标准,测量不同厚度Ti-6Al-7Nb合金铸件的挠度,并与纯钛、Ti-6Al-4V合金及Co-Cr合金对比。结果:Ti-6Al-7Nb合金、纯钛及Ti-6Al-4V合金铸件的厚度在0.65mm时可以达到义齿基托挠度的标准;Co-Cr合金在0.57mm时可达到标准要求。结论:在临床制作Ti-6Al-7Nb合金义齿基托时,厚度应不低于0.65mm。  相似文献   
98.
Bronchiolitis obliterans syndrome (BOS) is the limiting factor to long-term survival after lung transplantation. Previous studies suggested respiratory viral tract infections are associated with the development of BOS. To identify the impact of virus detection in bronchoalveolar lavage (BAL) fluid, we analyzed BAL samples from 87 consecutive lung transplant recipients for human herpesvirus (HHV)-6, Epstein-Barr virus, Herpes simplex virus 1/2, Cytomegalovirus, respiratory syncytical virus and adenovirus by PCR. Acute rejection, BOS and death were recorded for a mean follow-up time of 3.27 +/- 0.47 years. Results of PCR analysis and other potential risk factors were entered into a Cox regression analysis of BOS predictors and death. Only acute rejection was a distinct risk factor for BOS of all stages, death and death from BOS. HHV-6 was detected in 20 patients. Univariate and multivariate analysis revealed that HHV-6 was associated with an increased risk to develop BOS > orb = stage 1 and death, separate from the risk attributable to acute rejection. Identification of HHV-6 DNA in BAL fluid is a potential risk factor for BOS. Our results warrant further studies to elucidate a possible causal link between HHV-6 and BOS.  相似文献   
99.
100.
Differential Cellular Gene Expression in Ganglioglioma   总被引:1,自引:0,他引:1  
Summary:  Purpose:  Gangliogliomas (GGs) are neuronal-glial tumors highly associated with epilepsy. We hypothesized that the expression of select gene families including neurotransmitter receptor subunits and growth factors would be distinct in neurons and astrocytes within GG compared with adjacent cortex and that these changes would yield insights into seizure onset and lesion formation.
Methods:  Candidate gene expression was defined in single immunohistochemically labeled neurons and astrocytes microdissected from GG specimens compared with neurons and astrocytes microdissected from morphologically intact cortex adjacent to the GG or normal control cortex.
Results:  Differential expression of 16 genes including glutamate transporter (EAAC1) and receptor (NMDA2C, mGluR5), growth factor (hepatocyte growth factor), and receptor (platelet derived growth factor receptor β, fibroblast growth factor receptor 3) mRNAs was detected in GG neurons compared with control neurons. In astrocytes, altered expression of p75NGF, mGluR3, TGFβ3 and Glt-1 mRNAs was detected. Nestin mRNA, a gene that exhibits enhanced expression in balloon cell cortical dysplasia, was increased in GG neurons. Because of the morphological similarities between GG and cortical dysplasia, we show that there is activation of the mTOR cascade in GG as evidenced by enhanced expression of phospho-p70S6kinase and phosphoribosomal S6 proteins.
Conclusion:  We find differential candidate gene expression in neurons and astrocytes in GG compared with adjacent cortex and show that there is activation of the mTOR pathway. These changes highlight pathways that may be pivotal for epileptogenesis and lesion growth.  相似文献   
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