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21.
Wang Z 《Pflügers Archiv : European journal of physiology》2004,448(3):274-286
K+ channels are a most diverse class of ion channels in the cytoplasmic membrane and are distributed widely in a variety of cells including cancer cells. Cell proliferation and apoptosis (programmed cell death or cell suicide) are two counterparts that share the responsibility for maintaining normal tissue homeostasis. Evidence has been accumulating from fundamental studies indicating that tumour cells possess various types of K+ channels, and that these K+ channels play important roles in regulating tumour cell proliferation and apoptosis, i.e. facilitating unlimited growth and promoting apoptotic death of tumour cells. The potential implications of K+ channels as a pharmacological target for cancer therapy and a biomarker for diagnosis of carcinogenesis are attracting increasing interest. This review aims to provide a comprehensive overview of current status of research on K+ channels/currents in tumour cells. Focus is placed on the roles of K+ channels/currents in regulating tumour cell proliferation and apoptosis. The possible mechanisms by which K+ channels affect tumour cell growth and death are discussed. Speculations are also made on the potential implications of regulation of tumour cell proliferation and apoptosis by K+ channels. 相似文献
22.
Daniel T.L. Shek Li Zhao Diya Dou Xiaoqin Zhu Chenghan Xiao 《The Journal of adolescent health》2021,68(4):676-682
PurposeThis study examined the prevalence of posttraumatic stress disorder (PTSD) symptoms among adolescents in mainland China under COVID-19. The direct effects of the perceived threat of COVID-19 and positive youth development (PYD) qualities, as well as the moderating effect of PYD qualities on PTSD symptoms, were studied.MethodsFive schools in Chengdu, Sichuan, China, participated in this study. Two waves of data were collected before school lockdown (Wave 1, between December 2019 and January 2020) and after school resumption (Wave 2, between June 2020 and July 2020), respectively. A total of 4,981 adolescents aged above 11 years (Mean age = 13.15, SD = 1.32 at Wave 1, 51.5% girls) completed questionnaires at both waves. Students responded to measures of PYD qualities at both waves and perceived threat and PTSD symptoms at Wave 2.ResultsA total of 517 adolescents (10.4%) could be regarded as having PTSD. Results indicated significant unique main effects of perceived threat (β = .13, p < .001) and Wave 1 PYD qualities (β = ?.16, p < .001) on PTSD symptoms. Besides, results showed a significant moderating effect of PYD qualities in mitigating the negative impact of perceived threat on PTSD symptoms.ConclusionsThis study revealed the protective effect of PYD attributes in reducing the negative influence of traumatic situations such as COVID-19 on adolescent mental health. Results underscore the importance of promoting PYD qualities in adolescents in mainland China via effective PYD programs. 相似文献
23.
Isolation of Nanjing local strains of HHV-7 and their biological and immunological characteristics 总被引:2,自引:0,他引:2
To investigate the biological and immunological characteristics of the Nanjing local strains of HHV-7,fourstrains of herpesvirus were isolated from saliva specimens of one healthy individual and three childrensuffering from a kidney disease in Nanjing.The viruses were identified by transmission electron microscopy(EM),indirect immunofluorescence assay(IFA) with a specific monoclonal antibody;nested polymerase chainreaction,restriction mapping and DNA sequencing.The virus-infected cells showed the typical cytophathiceffect(CPE) under microscopy and could be detected by IFA with the human herpesvirus-7(HHV-7) specificantibody.Under EM,herpesvirus-like and virions capsids could be found in their cytoplasm or nucleoplasm.HHV-7 DNA fragments amplified from infected cells by nested PCR were confirmed by restriction mappingand DNA sequencing.Similarly to DC strain,an known HHV-7 strain used in the present study as the positivecontrol,the virus could be inactivated by ultraviolet irradiation for 10 min,heated at 45℃ for 30 min,pH<5or>9 at 4℃ for 2 h and ether or chloroform for 10 h.The virus induced the production of TNF-α,IL-10 andIL-12p70 while inhibited IFN-γ secretion,increased the percentage of CD2~+ cells while decreased that of CD4~+or CD45RA~+ cells.The results indicate that the viruses isolated in Nanjing are HHV-7,which has similarbiological characteristic to the known HHV-7 strain,DC.Infection with HHV-7 in vitro could affect immunefunction of lymphocytes by disturbing cytokine production and CD antigen expression.Cellular & MolecularImmunology.2004;1(5):367-372. 相似文献
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25.
p16与c-myc基因表达产物在肝细胞癌及癌旁组织中的表达及临床意义 总被引:3,自引:3,他引:0
目的:探讨p16、c-myc蛋白与肝细胞癌(HCC)的发生、发展及恶性程度的关系。方法:应用免疫组织化学法检测了69例HCC和63例癌旁组织p16及c-myc蛋白的表达,并结合临床资料进行分析。结果:p16蛋白主要分布在胞浆,少数细胞核内也可见阳性显色。c-myc蛋白主要分布在胞核。p16蛋白在肝癌组织及癌旁组织中的阳性率分别为26.5%(18/69)和92%(58/63),两者比较差异显著(P〉 相似文献
26.
肝移植术后出凝血功能的调控 总被引:18,自引:1,他引:17
目的:探讨肝移植术后出凝血功能的调控方法及意义。方法:通过11 例活体肝部分移植术病例,介绍术后出凝血功能的监测指标及调控方法。结果:肝移植术后出凝血功能调控的目标为维持血压、脉搏相对稳定,控制下列指标在一定范围内。 Hb :90 ~110g/ L, Ht:25 % 上下, P L T:30 ~50 ×109/ L, P T:15 ~20s , A C T:150 ~200s,调控手段是依据上述指标补充凝血因子或使用扩血管剂或抗凝剂。结论:本研究所介绍的方法能有效防止肝移植术后的出血和血栓形成。 相似文献
27.
采用口服氯化铝建立小鼠学习记忆障碍模型,应用跳台法观察了纳络酮对铝(Al)中毒所致小鼠学习记忆障碍的改善作用,用火焰原子吸收分光光度法测定血锌(Zn)、铜(Cu)、锰(Mn)等含量.结果显示,氯化铝可导致小鼠学习记忆障碍,且有降低血Zn、Cu含量的作用(P<0.05);纳络酮治疗有改善Al中毒小鼠学习记忆障碍的作用,同时也增加了血Zn、Cu的含量. 相似文献
28.
Increasing sampling density improves reproducibility of optical coherence tomography measurements. 总被引:1,自引:0,他引:1
R Gurses-Ozden H Ishikawa S T Hoh J M Liebmann A Mistlberger D S Greenfield H L Dou R Ritch 《Journal of glaucoma》1999,8(4):238-241
PURPOSE: Published series of peripapillary retinal nerve fiber layer (RNFL) measurements using optical coherence tomography (OCT) have sampled 100 evenly distributed points on a 360 degrees peripapillary circular scan. The goal of this study was to determine whether a four-fold increase in sampling density improves the reproducibility of OCT measurements. METHODS: Complete ophthalmic examinations, achromatic automated perimetry, and OCT imaging were performed in all patients. The OCT scanning consisted of three superior and inferior quadrantic scans (100 sampling points/quadrant) and three circular scans (25 points/quadrant). The RNFL thickness measurements and coefficient of variation (CV) were calculated for the superior and inferior quadrants for each sampling density technique. RESULTS: The study included 22 eyes of 22 patients (3 control subjects; 2 patients with ocular hypertension; and 17 patients with glaucoma). Quadrants with associated glaucomatous visual field loss on automated achromatic perimetry had thinner RNFLs than quadrants without functional defects for both the 25- and 100-points/quadrant scans. For quadrants associated with normal visual hemifields (n = 22), there was no difference between the 25- and 100-points/quadrant scans in mean RNFL thickness and CV. Among quadrants with visual field defects (n = 22), RNFL thickness measurements were thinner in the 25-points/quadrant scans than in the 100-points/quadrant scans. The CV for the 25-points/quadrant scans (25.9%) was significantly higher than that for the 100-points/quadrant scans (11.9%). CONCLUSION: Increasing the sampling density of OCT scans provides less variable representation of RNFL thickness. The optimal sampling density to achieve maximal reliability of OCT scans remains to be determined. 相似文献
29.
30.
VEGF、KDR的表达对肝癌的血管生成、生长、转移的影响 总被引:12,自引:0,他引:12
目的 研究血管内皮生长因子 (VEGF)及其受体KDR(kinaseinsertdomaincontainingre ceptor)对肝细胞肝癌的血管生成、生长、转移等方面的影响。 方法 对 45例肝癌、2 1例肝硬化、8例正常肝标本进行了免疫组化、原位杂交染色 ,然后行图像分析 ,观察VEGF、KDR的表达与肝癌病理特点之间的关系 ,并进行统计学分析。 结果 肝细胞肝癌中VEGF高表达 ;并与肝癌的血管生成相关 ;VEGF的表达强度与表达率均与肝癌的转移、包膜形成相关 ;KDR不仅表达于血管内皮细胞 ,还表达于部分肝癌细胞。 结论 VEGF在肝癌的血管生成、癌细胞转移、包膜形成中可能起到重要作用 ,KDR在肝癌细胞的表达可能是一种自分泌行为。 相似文献