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61.
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   
62.
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   
63.
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   
64.
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   
65.
CD44v6和组织蛋白酶D表达与食管癌预后的关系   总被引:2,自引:0,他引:2  
目的 研究CD4 4v6和组织蛋白酶D(cathepsinD ,CD)表达与食管癌生物学行为的关系。方法 应用免疫组化法 ,检测 6 5例食管鳞状细胞癌组织中CD4 4v6和CD表达水平。结果 在食管癌中CD4 4v6和CD表达阳性率分别为 5 8.5 %和 6 4 .6 %。CD4 4v6和CD表达均与肿瘤分级、浸润、淋巴结转移和预后相关。结论 CD4 4v6和CD异常表达与食管癌的病理生物学行为密切相关 ,可作为是预测食管癌转移潜能和评估食管癌预后的客观指标  相似文献   
66.
本文报告了2,4,6-三硝基甲苯(TNT)的代谢物,2-氨基-4,6-二硝基甲苯2和2,4-二氨基-6-硝基甲苯3的合成。以邻甲基苯甲酸为原料,经硝化(HNO_3-H_2SO_4)和Schmidt反应(NaN_3-H_2SO_4)得到2,用NaHS还原TNT的方法合成化合物3。  相似文献   
67.
Contralateral intrastriatal injection of 0.1 pmol or 1 pmol of endothelin-1 produced ipsilateral turning behaviour in rats with unilateral 6-hydroxydopamine (6-OHDA) lesions of the nigrostriatal pathway. This effect could be abolished by pretreatment with either the endothelinETA/B receptor antagonist bosentan (1 nmol, intrastriatally) or the dopamine D2 receptor antagonist raclopride (0.1 mg/kg, s.c.) suggesting that endothelin is acting at endothelin receptors to evoke ipsilateral turning behaviour and that this response is mediated by dopamine. Similar ipsilateral turning behaviour was observed upon intrastriatal injection of 1 pmol of endothelin-3 or the specific ETB receptor agonist, [Ala1,3,11,15]endothelin-1 when compared to endothelin-1. Pretreatment with the specific ETB receptor antagonist BQ788 blocked the ipsilateral turning response to intrastriatal injection of endothelin-1 while pretreatment with the specific ETA receptor antagonist BQ123 did not significantly change the response to injection of endothelin-1. This indicates that endothelin-1, which has affinity for both ETA and ETB receptors, is most likely acting at the ETB receptor to elicit its effect. These results suggest that low doses of endothelin may act at ETB receptors to evoke the release of dopamine from the striatum in vivo.  相似文献   
68.
The greater potency of morphine-6-glucuronide (M6G) as well as the inactivity of morphine-3-glucuronide (M3G) with respect to the antinociceptive effects of the parent molecule, morphine (MOR), have been well established. It has been suggested that M3G is an antagonist of MOR's antinociceptive and respiratory depressive effects. The present study addressed the central nervous system (CNS) interaction of these opiate metabolites on their metabolic and hormonal effects. Whole body glucose kinetics were assessed on conscious, chronically catheterized, unrestrained rats. M3G (5 μg) or H2O (5 μl) was injected intracerebroventricularly (i.c.v.) 15 min prior to the bolus administration of H2O (5 μl), M6G (1 μg), or MOR (80 μg). i.c.v. M3G (5 μg) resulted in behavioral excitation, hyperglycemia (+50%), stimulation of glucose rate of appearance (Ra; +100%), glucose rate of disappeaance (Rd; +70%), and metabolic clearance rate (MCR; +33%) within 30 min after injection with no alterations in hormone concentrations. i.c.v. M6G and MOR produced progressive hyperglycemia with significantly high catecholamine and corticosterone levels. M3G pretreatment resulted in enhanced elevations in plasma glucose levels (+52% and +18%), plasma lactate (+138% and +108%), norepinephrine (+96% and +30%), and epinephrine (+62% and +67%) in response to both i.c.v. MOR and M6G administration. These findings suggest a non-opiate and non-hormonal mechanism for M3G-induced hyperglycemia. In contrast, the metabolic and hormonal responses to i.c.v. M6G and MOR are associated with elevations in catecholamine and corticosterone levels, which are remarkably enhanced by M3G pretreatment, most likely through accelerated catecholamine release. Our findings suggest a modulatory role for MOR glucuronidation, not only by rendering it inactive, as in the case of M3G, but by an interplay of the metabolic effects of the parent molecule and its metabolite  相似文献   
69.
本文报道给C57小鼠腹腔注射不同剂量1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)后,发现组3(MPTP35 mg/kg,每天一次,共7天)鼠肝匀浆、线粒体和微粒体的膜丙二醛含量明显增加,与对照组相比分别增加70.5%,67%和51.4%(P<0.01),而组1(MPTP 35mg/kg,每4小时一次,共3次)和组2(MPTP35mg/kg,每天一次,共4天)鼠肝丙二醛含量与对照组相近。结果表明MPTP有明显地促进鼠肝脂质过氧化的作用,并与其剂量有关。  相似文献   
70.
 Buprenorphine, a partial mu-opioid receptor agonist, has been proposed as a treatment for cocaine abuse. However, studies in animals have produced conflicting results on the nature of the interaction between buprenorphine and cocaine. In some studies, buprenorphine attenuated the effects of cocaine and in others it enhanced them. The purpose of the present study was to evaluate the interaction of buprenorphine and cocaine on the rotational behavior of the nigrally-lesioned rat. Both buprenorphine (0.003–0.1 mg/kg) and cocaine (1.0– 30 mg/kg) alone produced dose-dependent increases in rotational behavior. Buprenorphine produced long-lasting turning with a peak at 60 min after administration, while cocaine produced turning that peaked immediately after administration and lasted for about 2 h. To distinguish simple additivity from other possible outcomes, we determined the relative potency of each drug alone, using a defined level of effect: 150 turns above the saline control in 4 h. This effect was produced by 10.0 mg/kg cocaine alone and by 0.0175 mg/kg buprenorphine alone. Based on these results, fixed ratio combinations were tested and the experimentally derived effects were compared to the theoretically additive values, using an isobolographic analysis. The fixed ratio combinations of the two drugs tested produced turning greater than predicted from simple additivity. This finding provides statistically-supported evidence for synergism between the actions of buprenorphine and cocaine. Received: 28 January 1997 / Final version: 7 June 1997  相似文献   
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