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1.
Abstract We previously demonstrated that epidermal growth factor (EGF) induces a several-fold increase in ornithine decarboxylase (ODC) activity and the steady-state level of ODC mRNA in cultured SV40-transformed human keratinocytes (1). Pretreatment of cell cultures with ultraviolet B (UVB) radiation resulted in a reduction of EGF-induced ODC activity. To determine whether UVB inhibits the accumulation of ODC mRNA by EGF, cells were pretreated with 20 mJ/cm2 UVB or sham-irradiated and then incubated with 100 ng/ml EGF. Northern blot analysis revealed that UVB irradiation entirely blocked the EGF induction of ODC mRNA. Since the binding of EGF to its plasma membrane receptor is the first step in initiating a biological response, the effect of UVB on EGF binding was evaluated. UVB treatment of cultured keratinocytes resulted in an immediate and dose-dependent reduction of EGF binding. Scatchard analysis revealed thai the reduction of EGF binding was due to a 52% decrease in the number of available receptors, from 6.2 × 104/cell to 3.0 × 104/cell. However, UVB decreased the EGF-binding affinity very little (Kd = 0.60 nM in control and Kd=0.75 nM in UVB-treated Z114 cells). In addition, UVB did not alter the rate of EGF internalization. These data suggest that UVB blocks the signal transduction pathway of EGF that is involved in regulation of ODC gene expression. Immunoblot analysis of extracts from irradiated cells showed that UVB induced tyro-sine phosphorylation of EGFR and that the quantity of EGFR protein was unaffected by UVB treatment. Phosphorylation of EGFR may be responsible for decreased binding of EGF to its receptor.  相似文献   
2.
OBJECTIVE: Oxidative stress such as free radical-mediated neuronal dysfunction may be involved in the pathophysiology of schizophrenia. The human glutathione peroxidase (GPX1) is a selenium-dependent enzyme, which plays an important role in the detoxification of free radicals. We therefore hypothesized that the GPX1 gene, which is located on chromosome 3p21.3, may be involved in the pathophysiology of schizophrenia. The aim of this study is to examine whether a potentially functional polymorphism, a proline (Pro) to leucine (Leu) substitution at codon 197 (Pro197Leu) of the human GPX1 gene, is associated with susceptibility to schizophrenia. METHODS: We genotyped the Pro197Leu polymorphism in a total of 113 nuclear families that had a proband with schizophrenia. Genetic association was tested using the transmission disequilibrium test (TDT), the sib transmission disequilibrium test (STDT), and the family-based association test (FBAT). RESULTS: The minor allele (Leu) frequency was calculated to be 0.282. We could not find significant transmission disequilibrium of the alleles for the Pro197Leu polymorphism in the GPX1 gene in association with the presence of schizophrenia in our family sample (TDT, chi2=0.03, degrees of freedom=1, P=0.86; combined TDT-STDT, Z'=-0.052, P=0.47; FBAT, Z=0.000, P=1.000). CONCLUSION: The results of this study suggest that the GPX1 polymorphism is unlikely to be associated with susceptibility to schizophrenia.  相似文献   
3.
益气活血类方剂配伍方法的探讨   总被引:1,自引:0,他引:1  
就气虚血瘀证的临床特征病因、病机进行了探讨,旨在为气虚血瘀证提供遭药组方依据,总结了益气活血类方剂的配伍规律,提出了以益气活血类方剂的配伍规律,提出了以益气活血法为主要治则,分别配行经气药,滋阻养血药,利水化痰药,浊阳散寒药达到气顺血调、标本同治。  相似文献   
4.
目的 :观察老年冠心病心功能不全患者血浆白细胞介素 6 (interleukin - 6 ,IL - 6 )浓度的变化。方法 :选择老年冠心病心功能不全患者 48例、心功能正常者 15例及健康老年人 30例 ,采用酶联免疫吸附法测定其血浆IL - 6浓度。结果 :冠心病心功能不全组血浆IL - 6浓度较冠心病心功能正常组及健康对照组明显增高 (均P <0 .0 5 ) ,而冠心病心功能正常组与健康对照组之间无明显差异 (P >0 .0 5 ) ;血浆IL - 6浓度与左室射血分数呈负相关 (r =- 0 .6 0 ,P <0 .0 1) ;因心功能不全恶化再入院患者血浆IL - 6浓度高于未再入院患者 (P <0 .0 1)。结论 :IL - 6具有判断病情、评价预后的价值  相似文献   
5.
目的 :探讨纤维支气管镜检查和经纤维支气管镜肺活检 (TBLB)对周围及弥漫性肺疾病的诊断价值。方法 :对 46 0例周围及弥漫性肺疾病患者 ,在无X线电视透视下行TBLB ,对临床资料及病理诊断结果进行回顾分析。结果 :46 0例周围及弥漫性肺疾病中有 35 1例明确了病因学的诊断 ,确诊率达 76 3% ,疾病种类主要有肺癌、肺结核、肺间质纤维化、肺结节病等 ,对临近胸膜的病变TBLB阳性率较低 ,并发症少见 ,仅有少量出血及发热 ,或偶有气胸。结论 :纤维支气管镜肺活检对周围及弥漫性肺疾病的诊断是一种可靠、安全、简便、经济、可重复操作的方法。  相似文献   
6.
目的 探讨滑膜软骨瘤病的临床、病理与X线联系及诊断价值.方法 回顾性分析了17例滑膜软骨瘤病的临床、病理及X线表现.结果 本病好发于下肢大关节,多为单关节.膝关节10例(双侧2例)、肩关节3例、髋关节、肘关节、腕关节、指掌关节各1例.主要临床表现:关节肿痛、弹响(6例),绞锁(3例),触及可活动或不活动性硬块(9例).X线特点:在关节内及其周围见数目、大小、密度、形态不一的钙化或骨化游离体.结论 正确判断和认识关节内游离体来源与发展的病理变化及X线表现对诊断本病有较重要的价值.  相似文献   
7.
目的:探讨结直肠癌肝转移的手术切除效果。方法:回顾分析结直肠癌并肝转移32例的临床资料,着重手术切除效果的分析。结果:32例结直肠癌肝转移患者中肝脏有1-3个转移灶者24例,在20例为同时性肝转移癌中,转移性与原发灶行一期切除者15例,分期(2-4周后)切除者5例。5例为结肠肝曲癌局部浸润转移。与原发灶整块切除,其它手术方式有不规则肝部分切除,肝左外叶切除,肝右后叶切除,肝右叶切除及肝右3叶切除等。全部病例均病理检查证实,无手术死亡,3年、5年生存率分别为37.5%和25.0%。结论:肝转移灶数目是影响疗效的主要因素。对肝转移灶手术切除是最有效的方法。但应合理选择具体手术方式。  相似文献   
8.
用半定量RT PCR检测了 38例急性白血病患者bcl 2基因表达。结果表明 ,临床复发难治组bcl 2基因表达明显高于初诊组和CR组 ,且bcl 2表达水平与临床复发难治呈正相关 (r =0 830 ,P <0 0 1)。提示bcl 2基因高水平表达是导致临床复发难治的因素之一 ;检测bcl 2表达水平对于衡量白血病患者对抗肿瘤药物敏感性及判断预后有一定意义。  相似文献   
9.
This review describes the recent growth of our knowledge in the genetics of these sleep disorders and reports some of our preliminary molecular studies in restless legs syndrome.  相似文献   
10.
Turkey herpesvirus (HVT) is widely used as an effective recombinant vaccine vector for expressing protective antigens of multiple avian pathogens from different loci of the HVT genome. These include the HVT029/031 (UL22–23) locus for the insertion of IBDV VP2 and the recently identified HVT005/006 locus as a novel site for expressing heterologous proteins. In order to compare the efficacy of recombinant vaccines with the HA gene at different sites, the growth curves and the HA expression levels of HVT-005/006-hCMV-HA, HVT-005/006-MLV-HA, and HVT-029/031-MLV-HA were first examined in vitro. While the growth kinetics of three recombinant viruses were not significantly different from those of parent HVT, higher expression of the HA gene was achieved from the HVT005/006 site than that from the HVT029/031 site. The efficacy of the three recombinant viruses against avian influenza H9N2 virus was also evaluated using one-day-old SPF chickens. Chickens immunized with HVT-005/006-MLV-HA or HVT-005/006-hCMV-HA displayed reduced virus shedding compared to HVT-029/031-MLV-HA vaccinated chickens. Moreover, the overall hemagglutination inhibition (HI) antibody titers of HVT-005/006-HA-vaccinated chickens were higher than that of HVT-029/031-HA-vaccinated chickens. However, HVT-005/006-MLV-HA and HVT-005/006-hCMV-HA did not result in a significant difference in the level of HA expression in vitro and provided the same protective efficacy (100%) at 5 days after challenge. In the current study, the results suggested that recombinant HVT005/006 vaccines caused better expression of HA than recombinant HVT029/031 vaccine, and that HVT-005/006-MLV-HA or HVT-005/006-hCMV-HA could be a candidate vaccine for the protection of chickens against H9N2 influenza.  相似文献   
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