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1.
目的:探讨小檗胺(BER)诱导K562细胞凋亡及其可能的机制。方法:以流式细胞仪(FCM)分析、电镜观察细胞微结构变化及基因组DNA电泳等方法检测细胞凋亡。以RT-PCR及Westernblot方法检测K562细胞BCR/ABLmRNA和蛋白质水平表达。结果:FCM检测见到典型的凋亡峰,8.0mg/LBER作用24-72h,随药物作用时间延长,细胞凋亡率由(29.20±3.82)%上升至(61.77±4.35)%(P<0.01);以2.0-8.0mg/LBER作用24h,随药物浓度增加,K562细胞的凋亡率也增加。电镜下可见明确的细胞凋亡的形态学改变。DNA电泳呈现典型的梯形条带。16.0mg/LBER处理24h,K562细胞bcr/ablmRNA相对表达量及BCR/ABL融合蛋白质P210水平均明显低于对照组,分别为0.73±0.02vs1.19±0.02(P<0.01)和0.63±0.01vs1.04±0.02(P<0.01),呈时间-浓度依赖效应。经BER作用后,K562细胞bcr/ablmRNA表达强度与P210水平呈正相关(r=0.928,P<0.05),且细胞凋亡率与bcr/ablmRNA表达呈负相关(r=-0.997,P<0.01)。结论:在体外BER对K562细胞有明显的促凋亡作用,抑制bcr/ablmRNA表达及其蛋白质水平可能是其作用的重要机制之一。  相似文献   

2.
目的研究R848对人自然杀伤细胞(NK)杀伤功能的作用及其机制。方法分离健康志愿者外周血单个核细胞(PBMC)、纯化NK细胞,加或不加R848进行培养。分别在0、2、6、24、48h收集培养细胞,流式细胞术检测R848对NK细胞表面活化分子CD25和CD69表达的影响;检测R848活化的NK细胞杀伤靶细胞K562的作用、通过检测颗粒酶A、B、穿孔素、TRAIL和NK细胞与靶细胞共孵育后CD107a/b的表达,探讨R848促进NK细胞的杀伤功能机制。结果 R848活化的NK细胞在培养24h时CD69和CD25分子的表达百分率和平均荧光密度达到峰值,随后活化分子的表达有所下降;R848活化的NK细胞对靶细胞的杀伤功能明显增强,TRAIL在不同NK细胞亚群的表达显著增加(P0.05)。当NK细胞与K562共孵育后,R848活化的NK细胞表面CD107a/b的表达较未刺激条件明显增加。结论 R848可直接作用于NK细胞促进其杀伤功能,其作用机制与NK细胞活化后释放颗粒酶和穿孔素增加,并且TRAIL的表达增加有关。  相似文献   

3.
目的 研究并比较3种卟啉类光敏剂——血卟啉衍生物(HpD)、癌光啉(PsD007)和血卟啉 单甲醚(HMME)诱导的光动力疗法(PDT)对白血病细胞K562的杀伤效应.方法 以人白血病细胞K562为研究对象,分为对照组和PDT组,以梯度浓度的光敏剂与K562细胞共同孵育,经不同能量光照后,用噻唑蓝(MTT)法测定PDT对K562细胞的杀伤作用.结果 与对照组相比,PDT对K562细胞有明显杀伤作用,并随着光敏剂浓度的增加和光照能量的增大,效果增强.PsD007-PDT和HMME-PDT的效果都明显优于HpD-PDT(P<0.05);而当光敏剂质量浓度较大(25 μg/ml)或能量密度较大(7.2 J/cm2)时,PsD007-PDT的作用效果优于HMME-PDT.结论 PDT对人白血病细胞K562具有明显的杀伤作用,其对细胞的抑制率具有显著的剂量效应关系;PDT对K562的杀伤效应与光敏剂种类有关,HpD-PDT的杀伤效果不如PsD007和HMME;在较高能量密度和较大光敏剂浓度的条件下,PsD007-PDT的效果优于HMME-PDT.  相似文献   

4.
目的探讨阿霉素体外作用于K562细胞后,观察其对细胞增殖的影响,促进细胞凋亡情况,以及调节细胞周期和粘着斑激酶(FAK)mRNA基因,进一步探讨通过调控FAK表达,研究抗白血病的作用机制。方法应用细胞增殖实验(CCK8法)观察不同浓度阿霉素作用不同时间对K562细胞增殖的影响,应用流式细胞仪观察不同浓度阿霉素对K562细胞细胞凋亡,细胞周期的影响,应用RT-PCR和Western blot技术检测不同浓度阿霉素作用对K562细胞36h后FAK mRNA以及蛋白表达水平的变化。结果随着阿霉素浓度增加及作用时间延长,K562细胞的增殖抑制率逐渐升高,同一时间不同浓度之间比较,或者同一浓度不同时间组之间比较,差异均有统计学意义(P〈0.05);阿霉素能引起K562细胞凋亡,且随着药物浓度增加,凋亡率也逐渐增加,差异均有统计学意义(P〈0.05);阿霉素能引起K562细胞周期阻滞,多停留在S期;阿霉素能引起K562细胞FAK mRNA表达显著降低。阿霉素能引起K562细胞FAK蛋白表达水平的降低。结论阿霉素抑制分裂期细胞的增殖,诱导细胞凋亡增加,对细胞FAK基因和蛋白水平均显著下调,为进一步研究FAK基因表达的调控与肿瘤细胞凋亡的分子机制提供了实验基础。  相似文献   

5.
舟山眼镜蛇细胞毒素1对K562细胞的抑制作用   总被引:1,自引:1,他引:0       下载免费PDF全文
目的: 研究舟山眼镜蛇细胞毒素1(CTX1)对人慢性粒细胞白血病细胞系K562的抑制作用。方法: 应用MTS方法和细胞计数法分别检测不同浓度CTX1作用K562后的细胞相对活力和细胞数;PI染色后用倒置荧光显微镜观察活细胞培养体系中K562细胞死亡情况;流式细胞术检测Annexin V-FITC和PI双染色后细胞凋亡情况。结果: 不同浓度的CTX1(2、5、10 mg/L)作用于K562细胞24 h,细胞相对活力分别为(90.50±3.07)%、(58.33±3.08)%和(27.43±1.99)%(与阴性对照组相比,下同,P<0.05),作用24 h时CTX1对K562细胞的半数抑制浓度为5.77 mg/L。CTX1(8 mg/L)作用于K562 6 h、12 h、24 h,细胞数分别占对照组的(85.01±3.54)%、(56.65±3.59)%和(43.24±4.15)%,P<0.05。随CTX1浓度增加和作用时间延长,荧光显微镜下观察到被PI染色的细胞数逐渐增多。CTX1(8 mg/L)作用于K562细胞6 h、12 h、24 h,细胞坏死率分别为(0.73±0.06)%、(13.90±0.46)%和(23.33±0.86)%;晚期凋亡率分别为(16.27±0.21)%、(26.90±1.23)%和(18.77±0.81)%。结论: CTX1对K562细胞有明显抑制作用,主要引起K562细胞晚期凋亡和坏死。  相似文献   

6.
目的探讨鲨鱼软骨制剂(SCP)诱导人红白血病细胞系(K562)凋亡的作用机制。方法以不同浓度SCP加入体外培养的K562细胞中,用MTT比色法检测细胞存活率;Hoechst33342/PI荧光染色,荧光显微镜分析凋亡细胞百分率;流式细胞术进行细胞凋亡定量;免疫细胞化学染色法检测Bcl-2蛋白的表达。结果SCP明显抑制K562细胞生长,IC50值为1mg/ml以下;荧光显微镜下可见50%以上细胞为凋亡细胞的形态学改变;免疫细胞化学检测显示SCP诱导细胞凋亡过程中Bcl-2表达明显降低。结论SCP诱导K562细胞凋亡,可能与下调Bcl-2表达有关。  相似文献   

7.
目的:探讨超抗原SEB活化并扩增的耐受调节性CD8+ NKT细胞对肿瘤细胞K562和A549的杀伤作用。方法:获取体外扩增0、10、20、30 d的耐受调节性效应细胞与K562和A549肿瘤细胞做混合淋巴细胞培养,MTT方法测定效应细胞对肿瘤细胞的杀伤作用。经荧光抗体染色、流式细胞术(FCM)解析效应细胞表面CD69分子的表达率和NKT细胞亚群百分数。结果:在效靶比20∶1时,效应细胞杀伤K562和A549细胞的百分率分别达到75.4%和67.2%(P0.05,n=3)。效应细胞的上清液未显示杀伤作用。效应细胞表面CD69分子的表达率随培养时间延长而增加,由0 d的0.11%增加到30 d的98.23%(P0.01,n=3)。效应细胞中CD8+ NKT细胞亚群随扩增时间延长而增加,由正常值(0 d)的0.36%增加到30 d的41.59%(P0.05,n=3)。结论:耐受调节性CD8+ NKT细胞在杀伤肿瘤细胞中起了重要作用。杀伤肿瘤细胞的作用机制是效应细胞的直接作用,与游离的细胞因子无关。  相似文献   

8.
抗DR5单克隆抗体-mDRA-6对白血病细胞的凋亡诱导作用   总被引:2,自引:0,他引:2  
目的:观察抗死亡受体5(DR5)单克隆抗体(mAb)-mDRA-6对白血病细胞的凋亡作用。方法:DR5蛋白免疫BALB/c小鼠,融合筛选抗DR5杂交瘤细胞,制备抗人DR5mAb-mDRA-6;荧光显微镜下观察mDRA-6作用下白血病细胞Jurkat、HL-60、K562的形态变化;MTT法测定不同浓度的mDRA-6对Jurkat、HL-60、K562细胞存活率的影响;通过FITC-Annexin V及PI标记细胞,以流式细胞术检测mDRA-6对Jurkat、HL-60、K562细胞凋亡率的影响。结果:mDRA-6导致Jurkat、HL-60细胞染色质浓缩、断裂,细胞出芽,凋亡小体形成;mDRA-6对Jurkat、HL-60细胞具有明显的杀伤作用,但对K562的杀伤作用较弱,25mg/L的mDRA-6作用12h,Jurkat、HL-60、K562细胞死亡率分别为88.76%,59.76%,5.18%。Annexin V及PI双染显示1mg/L的mDRA-6作用10h,Jurkat细胞凋亡率为86.06%,10mg/L的mDRA-6作用10h,HL-60细胞凋亡率为48.11%,但10mg/L的mDRA-6作用K562细胞10h,细胞凋亡不明显。结论:抗DR5mAb mDRA-6能够诱导白血病细胞凋亡,不同的白血病细胞株对mDRA-6的敏感性不同。  相似文献   

9.
人参皂苷Rg1诱导人白血病K562细胞复制性衰老的机制   总被引:1,自引:1,他引:0  
目的 探讨人参皂苷Rg1(Rg1)诱导人白血病K562细胞复制性衰老特征性变化.方法 四甲基偶氮唑盐(MTT)法筛选Rg1对K562细胞增殖抑制的最佳浓度及时间,以此浓度和作用时间诱导K562细胞衰老.流式细胞术检测Rg1对细胞增殖周期的影响;衰老相关β-半乳糖苷酶(SA-β-Gal)染色检测阳性细胞百分率;Southern blotting检测端粒长度;Western blotting检测复制性衰老信号通路相关P21、P53与Rb蛋白表达;透射电镜观察人白血病K562细胞衰老超微形态学改变.结果 Rg1在体外能明显抑制K562细胞增殖,其最佳作用浓度为20 μmol/L,时间为48h;诱导后的K562细胞阻滞于G2/M期;SA-β-Gal染色阳性细胞百分率增加(P<0.05);复制性衰老通路相关蛋白P21、P53和Rb表达上调(P<0.05);端粒长度缩短加速(P<0.05);经诱导细胞呈现胞体增大,溶酶体体积增大、数目增多,线粒体体积增大等衰老形态学变化.结论 Rg1可能经由p53-p21-Rb信号通路诱导K562细胞呈现复制性衰老特征.  相似文献   

10.
索拉非尼联合柔红霉素对白血病K562细胞的抑制作用   总被引:2,自引:0,他引:2       下载免费PDF全文
目的:探讨小分子Raf激酶抑制剂索拉非尼(sorafenib)联合柔红霉素(DNR)对白血病细胞K562及U937的抑制作用及可能的分子机制。方法:MTT法测定索拉非尼和柔红霉素单独作用于K562和U937细胞的抑制率及DNR IC10联合不同浓度索拉非尼作用于K562及U937的联合抑制率;流式细胞AnnexinⅤ/PI法测定单药及联合用药后K562细胞的凋亡率以及Hoechst33258染色法观察单药及联合作用后细胞凋亡形态的改变;West-ern blotting法测定索拉非尼、DNR及U0126对K562及U937p-ERK1/2的影响;根据金氏方程证明2种药物联合抑制率及凋亡是否有协同作用。结果:MTT法测定索拉非尼联合DNR对K562及U937均有协同抑制作用(q1.15,P0.01);流式细胞AnnexinⅤ/PI和Hoechst33258染色法,均证明索拉非尼联合柔红霉素能联合诱导K562细胞凋亡(q1.15,P0.05),两者有明显的一致性;K562细胞的基础pERK1/2蛋白水平明显高于U937细胞(P0.01),索拉非尼和U0126都能够显著抑制K562细胞p-ERK1/2水平;U0126联合DNR存在协同抑制K562细胞的作用。结论:索拉非尼联合DNR作用于白血病细胞K562、U937存在协同抑制及凋亡诱导作用;DNR对U937的抑制作用明显高于K562;索拉非尼对K562的敏感性高于U937细胞;索拉非尼可能通过下调p-ERK1/2水平增加柔红霉素抗白血病细胞的效应。  相似文献   

11.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

12.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

13.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

14.
15.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

16.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

17.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

18.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

19.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

20.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

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