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991.
胃癌中hMSH2、p53和PCNA表达的相关性及意义 总被引:4,自引:1,他引:3
目的:探讨胃癌中hMSH2、p53和PCNA表达的相关性及意义.方法:采用免疫组织化学SP法,检测胃癌、癌旁和胃炎粘膜中hMSH2、p53和PCNA表达情况.结果:1)3种基因产物在胃癌中的阳性率均显著高于非癌组织,其中,p53和PCNA在低分化癌中的阳性率显著高于高分化癌,有淋巴结转移者显著高于无转移者(P<0.05).2)胃癌中hMSH2/PCNA及p53/PCNA表达均呈正相关(P<0.05).结论:hMSH2、p53和.PCNA的异常表达及hMSH2与PCNA之间的相互调节可能与胃癌的发生发展密切相关. 相似文献
992.
旋覆花素及苦碟子对过度训练大鼠肾组织细胞凋亡调控基因的影响 总被引:1,自引:1,他引:0
目的:观察旋覆花素及苦碟子对过度训练大鼠肾组织细胞Bax和Bcl-2的表达以及Bax/Bcl-2比值变化的影响,探讨上述二种药物抗肾组织细胞凋亡的分子机制。方法:采用大鼠游泳至力竭建立过度训练模型,将大鼠随机分为安静对照组、力竭运动组(力竭6h、力竭24h)、旋覆花素防治组(旋覆花素6h、旋覆花素24h),苦碟子防治组(苦碟子6h、苦碟子24h)。采用免疫组织化学方法检测大鼠肾组织Bax、Bcl-2蛋白的表达;采用CMIAS病理图像分析仪测量Bax、Bcl-2蛋白表达的平均光密度。结果:力竭后6h及24h大鼠肾组织Bax的表达增强(P〈0.05),Bcl-2的表达减弱(P〈0.05),Bax/Bcl-2比值明显增高(P〈0.05);旋覆花素和苦碟子6h及24h组大鼠与同期力竭组比较,Bax的表达减弱(P〈0.05),Bcl-2的表达增高(P〈0.05),Bax/Bcl-2比值降低(P〈0.05)。结论:旋覆花素和苦碟子均可通过调节Bax、Bcl-2及Bax/Bcl-2比值而起到抗过度训练大鼠肾组织细胞凋亡的作用。 相似文献
993.
目的:探讨环氧合酶-2(COX-2)与Ki-67在宫颈癌及正常宫颈组织的表达情况及其临床意义.方法:采用免疫组织化学法(SP法)检测COX-2与Ki-67在62例宫颈癌和20例正常宫颈组织中的表达.结果:宫颈癌组织COX-2的阳性表达与组织学类型、分化程度和淋巴转移相关(P<0.05或P<0.01),与临床分期无明显相关(P>0.05);而Ki-67蛋白的阳性表达与宫颈癌的分化程度及淋巴转移有关(P<0.05或P<0.01),而与组织细胞学类型及临床分期无明显相关(P>0.05).结论:COX-2与Ki-67的表达与宫颈癌的生长及转移密切相关. 相似文献
994.
L. Pantoni C. Sarti F. Pescini S. Bianchi L. Bartolini P. Nencini A. M. Basile M. Lamassa R. N. Kalaria M. T. Dotti A. Federico D. Inzitari 《European journal of neurology》2004,11(11):782-787
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a genetically transmitted cerebrovascular disease. Typically, the first clinical manifestation is migraine and the full clinical spectrum of the disease with recurrent strokes of the subcortical type, cognitive, and mood disorders is seen during the fourth and fifth decades of life. Vascular risk factors are usually absent in CADASIL patients and the diagnosis of the disease is particularly suspected in young adults with cerebrovascular events of unknown cause, diffuse leukoencephalopathy on computed tomography or magnetic resonance imaging, and a history of cerebrovascular diseases or dementia in many family members. We describe three Italian CADASIL patients who presented to medical attention for cerebrovascular events occurred after the age of 55 and had, in addition to hypertension and hyperlipidemia, thrombophilic risk factors such as hyperhomocysteinemia, elevated levels of lipoprotein(a), and antiphospholipid antibodies. Symptoms possibly related to cortical involvement, such as dysphasia and visual field deficits, were reported by two of these patients. We conclude that a diagnosis of CADASIL should not be disregarded in patients with vascular risk factors and presenting with symptoms not immediately referable to subcortical damage at ages more advanced than commonly reported. 相似文献
995.
C. Calatozzolo A. Salmaggi B. Pollo F.L. Sciacca M. Lorenzetti A. Franzini A. Boiardi G. Broggi C. Marras 《Neurological sciences》2007,28(6):304-310
Recent studies have shown an anti-tumour activity of cannabinoid receptors CB1 and CB2 in gliomas. This effect was mediated
by neurotrophins in breast and prostate carcinoma, while in gliomas this relationship has not yet been considered. The aim
of this study was to investigate the expression of cannabinoid receptors CB1 and CB2, neurotrophin NGF and NT-3 and their
receptors TrkA and TrkC in glioma and endothelial cells. The analysis was performed in 14 gliomas and 2 non-tumour brain specimens
by immunohistochemistry and real-time quantitative-polymerase chain reaction (RTQ-PCR). Gliomas showed a weak immunoreactivity
for CB1 and CB2 in tumour and in endothelial cells, and for NGF/TrkA mainly in tumour cells, while a moderate/diffuse immunoreactivity
was found for NT-3/TrkC. CB2 was expressed on 3 out of 6 low-grade gliomas and in all high-grade gliomas. Non-tumour brain
tissues were weakly positive in astrocytes and endothelium for CB1, CB2, NT-3 and TrkC and negative for NGF and TrkA. By RTQ-PCR,
gliomas showed low mRNA levels of NGF/TrkA and moderate levels of CB1, NT-3 and TrkC. CB2 mRNA expression was low or absent.
A potential role of cannabinoids, particularly of CB2 agonists devoid of psychotropic side effects, in glioma therapy could
have a basis in glioblastomas, because they were all positive, though weakly, to CB2. The presence of neurotrophins and their
receptors, mainly NT-3 and TrkC, suggests a possible role of these pathways in glioma growth/invasion, but further investigations
are required to verify this hypothesis and a potential relationship between cannabinoids and neurotrophins. 相似文献
996.
Fas、Bcl-2在γ射线体外诱发的白血病小鼠骨髓细胞中的表达 总被引:2,自引:0,他引:2
目的 :观察 Fas、Bcl- 2在 γ射线体外诱发的急性淋巴细胞白血病小鼠骨髓细胞中表达情况 ,以探讨辐射致癌的机制。方法 :采用 4次 1.75 Gyγ射线全身照射 BAL B/ c小鼠诱发白血病模型 ,通过流式细胞仪对照射后白血病组、未癌变组及对照组小鼠骨髓细胞中 Fas、Bcl- 2的表达进行检测 ;应用抗 Fas抗体诱导细胞凋亡 ,进一步观察 Fas、Bcl- 2的表达对骨髓细胞凋亡的影响。 结果 :白血病小鼠骨髓细胞 Fas表达较未癌变组及对照组明显下降 (P<0 .0 1) ,而 Bcl- 2的表达明显增强 (P<0 .0 1) ;白血病小鼠骨髓细胞明显耐受抗 Fas抗体诱导的细胞凋亡。 结论 :Fas低表达、Bcl- 2高表达导致了细胞凋亡受到抑制 ,这可能是辐射引起小鼠急性淋巴细胞白血病的机制之一。 相似文献
997.
Castardo JC Prudente AS Ferreira J Guimarães CL Monache FD Filho VC Otuki MF Cabrini DA 《Journal of ethnopharmacology》2008,118(3):405-411
Garcinia gardneriana (Planch. & Triana) Zappi (Clusiaceae) is widely distributed in Brazil and used in folk medicine to treat inflammation, pain, and urinary tract and other infections. However, very few studies have analyzed these therapeutic effects. In this study, the anti-inflammatory effects of the hydroalcoholic extracts from Garcinia gardneriana (HEGG) and some of its isolated biflavonoids were evaluated. The results showed that HEGG from the leaves, bark and seeds reduced carrageenan-induced mouse paw inflammation, in addition to diminishing the myeloperoxidase activity in the stimulated tissues. The reduction of neutrophil infiltration by treatment with the HEGG from leaves was confirmed by histology. The leaf extract also reduced the paw oedema evoked by bradykinin, histamine, prostaglandin E2 and 12-O-tetradecanoylphorbol acetate. However, it partially decreased substance P and compound 48/80-caused paw oedema, without any influence on the arachidonic acid-induced oedema. Both of the isolated compounds, fukugetin and GB-2a, prevented the carrageenan-induced paw oedema. In conclusion, this study showed important anti-inflammatory effects of HEGG through its interaction with different intracellular signaling pathways, without interfering with the formation of arachidonic acid (AA) metabolites. These characteristics, in addition to the wide distribution and culturing ease of the plant, confirm its popular use and highlight its promise in the development of new anti-inflammatory drugs. 相似文献
998.
雷公藤多甙抑制大鼠精子发生的研究 总被引:7,自引:0,他引:7
目的探讨雷公藤多甙对大鼠精子发生的抑制作用及其可能的信号通路。方法成年雄性大鼠给予雷公藤多甙(16 mg/kg)灌胃,每日1次,在2及6周检测血清睾酮(T)、卵泡刺激素(FSH)、黄体生成素(LH)和可的松水平;光镜观察睾丸组织的形态学变化;原位末端标记法(TUNEL)观察睾丸生精细胞凋亡;免疫组织化学法观察凋亡通路相关蛋白Bax/Bcl-2的表达。结果给药组与对照组相比,性激素、肾上腺皮质激素均无显著变化(P均>0.05);给药2周后精子数下降和畸形率上升(P<0.05),给药4和6周精子数下降和畸形率升高更显著(P<0.001);组织学检查给药组大鼠生精小管内各级精母细胞和精子细胞数明显减少,生精细胞排列紊乱,原始精原细胞和支持细胞(Sertoli细胞)未见明显改变。与正常对照组相比,生精小管内生精细胞凋亡显著增加(2周P<0.05,4和6周P<0.001)。凋亡相关蛋白Bax表达明显上调,Bcl-2表达无显著差异。结论雷公藤对大鼠精子发生的抑制作用表现为增加生精细胞凋亡,导致精子计数下降,精子的畸形率升高。雷公藤多甙使睾丸Bax表达增加,与诱导生精细胞凋亡相关,可能是相关的信号通路之一。进一步研究雷公藤多甙作用的分子信号机制有助于今后降低剂量、减少毒副作用,探讨其作为一种安全的男性避孕药可能性。 相似文献
999.
A methoxylated fatty acid that inhibits phospholipase A(2) (PLA(2); EC 3.1.1.4) was purified from the brown seaweed Ishige okamurae. Approximately 8.1 mg of the inhibitory compound, 7-methoxy-9-methylhexadeca-4,8-dienoic acid, was isolated from 1 kg of I. okamurae powder. Recombinant PLA(2) derived from the pathogenic bacterium Vibrio mimicus was used as the target enzyme. The methoxylated fatty acid compound competitively inhibited PLA(2) with a Ki value of 3.9 microg/mL. The concentrations required for 50% inhibition of PLA(2), oedema and erythema were 1.0 microg/mL, 3.6 mg/mL and 4.6 mg/mL, respectively. The compound strongly inhibited PLA(2) activity in vitro and had potent antiinflammatory activity in vivo. 相似文献
1000.
Background: There are many surgical procedures for the correction of hallux valgus and crossover 2nd toe deformity. Amputation of a crossover 2nd toe is often performed as a salvage procedure if the primary 2nd toe corrective procedure fails.Aims: To assess the outcomes of amputating a crossover 2nd toe in the presence of hallux valgus in elderly patients above 70 years old; as a primary procedure.Materials and methods: Seven patients (8 ft) underwent amputation of their crossover 2nd toe. A disease specific questionnaire using a Visual Analogue Scale (VAS) was implemented measuring pain, deformity, discomfort, and walking distance.Results: The mean age of the patients was 82 years old, range 74–89 years old. Amputation of the 2nd toe significantly reduces pain, discomfort and the appearance of deformity, there was no difference in the patient’s walking distance after surgery.Conclusion: We recommend this type of surgery as a primary procedure in elderly patients above 70 years old, if the first ray is not causing symptoms. 相似文献