XAV939对卵巢癌细胞侵袭迁移的影响及Wnt/β-catenin信号的抑制作用

目的 探讨XAV939对卵巢癌细胞侵袭转移方面的影响及其对Wnt/3-catenin信号转导途径的抑制作用.方法 采用MTT法检测XAV939对卵巢癌细胞活力的抑制作用,划痕实验观察XAV939对细胞迁移能力的影响,Transwell细胞迁移实验检测XAV939对卵巢癌细胞侵袭转移的影响,Western blot方法检测wnt1、β-catenin、TCF4蛋白以及基质金属硫蛋白9 (Metallothionein matrix protein,MMP9)的表达水平.结果 XAV939作用48 h后,抑制率明显上升,尤其浓度达到8μmol/L(31％±1％,P =0.034)、16 μmol/L(51％±4％,P=0.028),且划痕和Transwell实验结果显示XAV939能抑制卵巢癌的侵袭和转移.此外,western blot结果显示,wnt1、β-catenin、TCF4、MMP9的表达水平均有所降低.结论 XAV939通过Wnt/β-catenin信号通路来抑制卵巢癌细胞的侵袭和迁移.     

Oct4基因沉默对结直肠癌细胞凋亡的诱导作用及机制研究

目的 探讨Oct4基因沉默对人结直肠癌SW480细胞凋亡的影响及其可能机制.方法 将对数生长期SW480细胞分为3组.①空白对照(Con)组:不转染病毒;②阴性对照(NC)组:转染阴性对照病毒;③RNA干扰(RNAi)组:转染Oct4-shRNA慢病毒载体.采用实时荧光定量PCR检测Oct4 mRNA表达;采用Western blotting检测Oct4、p-Akt 蛋白表达;采用流式细胞仪测定Oct4+及CD44+细胞比例变化及肿瘤细胞凋亡情况.结果 与NC组比较,RNAi组Oct4 的mRNA(分别为1.00和0.19±0.02)和蛋白(分别为0.032±0.004和0.007±0.001)表达量均有明显下降(P＜0.0l),Oct4+细胞比例(分别为91.53％和10.70％)和CD44+细胞比例(分别为59.69％和23.58％)明显减少,p-Akt蛋白表达明显受抑(0.11+0.03和0.03±0.01),细胞凋亡明显增加(分别为l2.1％±1.8％和43.2％±4.5％,P＜0.01).结论 沉默Oct4基因可明显减少SW480细胞中Oct4+及CD44+细胞比例,增加细胞凋亡,其作用可能与PI3K/Akt通路有关.     

DDX5基因表达下调对胃癌细胞增殖、迁移及侵袭影响

目的探讨DDX5基因表达下调对胃癌细胞增殖、迁移和侵袭的影响。方法采用慢病毒介导的DDX5-shRNA下调人胃癌HGC-27细胞中DDX5的表达。实时荧光定量PCR和蛋白免疫印迹(Western blot)法验证下调效果。CCK8和平板克隆检测细胞增殖能力,Transwell检测细胞迁移和侵袭能力的改变。结果 DDX5-shRNA可有效下调人胃癌HGC-27细胞中DDX5的mRNA和蛋白质表达。DDX5表达下调后,人胃癌HGC-27细胞的增殖受到抑制,24、48、72 h细胞增殖能力较转染了control-shRNA的细胞分别降低25.0%、33.3%和44.6%;转染了control-shRNA的细胞和转染了DDX5-shRNA的细胞克隆形成的数目分别为(162.6±10.3)个和(68.7±11.2)个,两组间比较,差异有统计学意义(P<0.05);转染了control-shRNA的细胞和转染了DDX5-shRNA的细胞24 h迁移数目分别为(153.7±9.2)个和(78.0±6.7)个,两组间比较,差异有统计学意义(P<0.05);转染了control-shRNA的细胞和转染了DDX5-shRNA的细胞24 h侵袭数目分别为(83.7±12.8)个和(40.2±7.6)个,两组间比较,差异有统计学意义(P<0.05)。结论 DDX5表达下调可明显抑制人胃癌HGC-27细胞的增殖、迁移及侵袭,其有可能成为胃癌的治疗靶点。     

组织蛋白酶B表达对结直肠癌细胞侵袭行为的影响

目的探讨组织蛋白酶B(CatB)表达对结直肠癌细胞黏附和侵袭行为的影响。方法选用人结肠癌细胞系LoVo和人直肠癌细胞系HR-8348,将含CatB全长cDNA的质粒pcDNA3CatB分别转染LoVo和HR-8348细胞。用RT-PCR方法检测CatBmRNA表达,采用细胞学实验方法分别测定并比较对照组、空载体转染组和CatB转染组细胞的黏附能力和细胞侵袭能力。结果CatB转染后,LoVo、HR-8348细胞中可检测到CatBmRNA的表达。对照组、空载体转染组、CatB转染组LoVo细胞与基质蛋白的黏附力分别为0.4616±0.1487、0.4121±0.2158、0.6916±0.1508。CatB转染组LoVo细胞黏附率高于对照组和空载体转染组,差异有显著性意义(F=5.8390,P<0.01)。对照组、空载体转染组、CatB转染组HR-8348细胞与基质蛋白的黏附率分别为0.4514±0.1195、0.5325±0.0999、0.7193±0.1013。CatB转染组HR-8348细胞黏附力高于对照组和空载体转染组,差异有显著性意义(F=13.1034,P<0.01)。对照组、空载体转染组和CatB转染组LoVo细胞侵袭数分别为47.09±8.16、52.41±6.24、66.47±8.77,三组细胞的侵袭能力有显著差异(F=9.8843,P<0.01),CatB转染组LoVo细胞侵袭数高于对照组和空载体转染组。对照组、空载体组和CatB转染组HR-8348细胞侵袭数分别为43.18±4.57、45.99±6.24、72.41±9.34,三组细胞侵袭力有显著差异(F=31.8474,P<0.01)。CatB转染组HR-8348细胞侵袭数高于对照组和空载体转染组。结论CatB表达增强了结直肠癌细胞的运动迁徙能力和与细胞外基质的黏附能力,可促进癌细胞的侵袭和转移。     

FasL诱导HIF-1α表达对直肠癌细胞侵袭行为的影响

目的探讨FasL诱导缺氧诱导因子1-α(HIF-1α)表达对直肠癌细胞侵袭行为的影响。方法将含FasL全长cDNA的真核表达载体pcDNA3.1 FasL转染人直肠癌细胞系HR-8348,通过Transwell侵袭小室实验检测癌细胞的侵袭能力,Western blot法检测细胞不同缺氧时点HIF-1α表达水平。结果细胞侵袭实验表明,FasL转染组HR-8348细胞穿透Transwell滤膜细胞数为12.9±2.4,明显多于空载体转染组和对照组(分别为7.7±2.1和8.1±2.0,P<0.05)。各组细胞在缺氧0h时点无HIF-1α表达,6h时点HIF-1α仅有微量表达,缺氧12h与24h时点FasL阳性细胞组(FasL转染组)HIF-1α表达水平明显提高(P<0.05),FasL阴性细胞组(对照组和空载体转染组)HIF-1α表达水平无显著变化(P>0.05)。同一缺氧时相HIF-1α表达水平组间比较,缺氧0h与6h各组间均无显著性差异(P>0.05),缺氧12h与24h转染FasL组显著高于空载体转染组和对照组(P<0.01)。结论直肠癌细胞中FasL诱导HIF-1α表达的因素,可促进直肠癌细胞对缺氧的适应及提高癌细胞的侵袭能力。     

miR-451对结肠癌细胞系SW620生物学行为的影响

目的探讨miR-451对结直肠癌细胞SW620增殖、凋亡及侵袭能力的影响。方法将SW620细胞分为4组:miR-451模拟物(miR-451 mi mics)转染组(细胞转染miR-451 mi mics,终浓度100nmol/L),NC组(细胞转染miRNA阴性对照,终浓度100nmol/L),空白转染组(加入与前2组等量的Lipofectamine 2000,无miRNA片段),对照组(细胞常规培养,不加入Lipofectamine 2000和miR-NA片段)。应用荧光定量RT-PCR检测转染24h后miR-451表达量的改变,采用CCK-8试剂盒检测转染24、48、72h后细胞的增殖能力,流式细胞仪检测转染48h后细胞凋亡情况,Transwell侵袭实验检测转染24h后细胞侵袭能力的改变,细胞免疫荧光和Westernblotting检测转染48h后巨噬细胞迁移抑制因子(MIF)的表达情况。结果转染后24h,荧光定量RT-PCR检测结果显示,miR-451mi mics转染组的miR-451表达量(67.96±13.33)较NC组(以其miR-451表达量作为1)显著上调(P<0.01)。与另外3组比较,miR-451 mi mics转染组细胞增殖能力在转染后48、72h明显受抑(P<0.01),但转染后48h其细胞凋亡率无明显改变(P>0.05)。转染后48h,miR-451 mi mics转染组、NC组、空白转染组、对照组中MIF蛋白表达阳性细胞的比例分别为23.9%±14.9%、53.5%±14.1%、45.2%±19.8%、59.3%±22.2%,统计学分析显示miR-451 mi mics转染组与其他3组比较差异显著(F=7.356,P<0.01)。Transwell侵袭实验显示,miR-451 mi mics转染组侵袭细胞数(37.4±6.1个/视野)明显低于对照组(61.6±8.6个/视野)、NC组(55.6±3.6个/视野)、空白转染组(60.8±7.4个/视野,P均<0.01)。结论上调miR-451表达可抑制结直肠癌细胞的生物活性,该作用可能与抑制MIF表达有关。     

骨髓基质干细胞与微粒皮组织促进皮肤缺损创面愈合的实验研究

目的 探讨骨髓基质干细胞(BMSCs)与微粒皮组织移植对皮肤缺损创面愈合的影响.方法 分离、培养、鉴定雄性F344大鼠骨髓基质干细胞;在大鼠背部形成4cm×4cm皮肤全层缺损创面;48只雌性F344大鼠随机均分为4组,A组行骨髓基质干细胞注射+微粒皮组织创面移植,B组仪行微粒皮组织创面移植,C组仅注射骨髓基质干细胞,D组仅行生理盐水(0.5ml)创面注射.移植的微粒皮组织占1/4创面面积,注射5×106个BMSCs细胞.雌性Wistar大鼠异体皮覆盖创面.观察术后14d创面愈合率、创面愈合时间、创面收缩率,并行Y染色体检测,以观察骨髓基质干细胞在创面的成活增殖情况.结果 A、B两组创面愈合率(分别为85.8%±3.5%、62.2%±4.4%)远高于C、D组(分别为30.4%±1.7%、30.0%6±1.3%),且A组显著高于B组(P<0.01),但C、D两组间比较没有显著性差异(P=0.898).A、B两组愈合时间(分别为17.2±1.6、20.3±2.4d)明显短于C、D组(分别为23.1±1.3、25.2±1.5d),且A组明显短于B组,C组明显短于D组(P<0.01).A、B两组收缩率(分别为36.9%±1.9%、39.6%±2.9%)明显小于C、D组(分别为92.5%±1.4%、92.4%±1.9%),且A组明显小于B组,而C、D两组的创面收缩率比较没有显著性差异.在A组、C组组织标本中可检测到数量不等的Y染色体阳性细胞.结论 BMSCs可在移植创面成活,能够与微粒皮组织相互作用,促进创面愈合.     

长链非编码RNA GAS5对胰腺癌AsPC-1细胞凋亡、迁移及侵袭能力调控作用

目的 探讨长链非编码RNA GAS5(lncRNA GAS5)对胰腺癌AsPC-1细胞凋亡、迁移及侵袭能力的调控作用。方法 在胰腺癌细胞系AsPC-1中通过转染质粒过表达lncRNA GAS5,将转染pcDNA3质粒的AsPC-1细胞组设为对照组,将转染pcDNA3-GAS5质粒的AsPC-1细胞组设为实验组。通过实时定量PCR、流式细胞学、细胞划痕实验、Transwell实验等方法检测lncRNA GAS5对胰腺癌细胞凋亡、迁移及侵袭能力的调控作用。结果 实时定量PCR结果显示,实验组AsPC-1细胞系中GAS5表达升高。流式细胞学检测显示,与对照组比较,转染GAS5对胰腺癌细胞凋亡影响不显著。细胞划痕实验显示,转染GAS5对胰腺癌细胞迁移能力抑制明显。Transwell实验结果显示,转染GAS5对胰腺癌细胞侵袭能力抑制明显。结论 lncRNA GAS5可能通过抑制胰腺癌细胞的迁移及侵袭功能发挥调控作用。     

小RNA干扰沉默S100A13对甲状腺细胞侵袭、迁移的影响及机制

 目的 探究干扰钙结合蛋白A13(calcium binding protein A13, S100A13)基因表达对甲状腺癌TPC-1细胞侵袭、迁移的影响及可能作用机制。方法 采用小RNA干扰敲减甲状腺癌TPC-1细胞S100A13基因的表达,通过细胞划痕实验和Transwell迁移实验检测S100A13对TPC-1细胞迁移能力的影响,Transwell侵袭实验检测S100A13对TPC-1细胞侵袭能力的影响,免疫印迹试验(Western Blot)检测S100A13、基质金属蛋白酶2(MMP-2)、钙黏蛋白E(E-cadherin)、波形蛋白(Vimentin)蛋白的表达。结果 与对照组相比,采用小RNA干扰的人甲状腺癌TPC-1细胞划痕宽度显著升高(25.214±2.687 vs 69.223±5.291),侵袭(0.897±0.082 vs 0.521±0.053)、迁移(1.263±0.252 vs 0.759±0.062)能力显著降低(P<0.05),细胞中MMP-2(0.523±0.062 vs 0.246±0.033)、Vimentin(0.863±0.082 vs 0.458±0.053)蛋白表达显著降低(P<0.05),E-cadherin(0.445±0.053 vs 0.755±0.078)蛋白表达显著增加(P<0.05)。结论 采用小RNA干扰S100A13表达可抑制甲状腺癌TPC-1细胞的侵袭、迁移,可能与其下调上皮间质转化和MMP-2的表达有关。     

组织蛋白酶B诱导HIF-1α表达对结肠癌细胞侵袭行为的影响

 目的 探讨组织蛋白酶B(CatB)诱导缺氧诱导因子-1α(HIF-1α)表达对直肠癌细胞侵袭行为的影响.方法 将CatB cDNA转染人结肠癌细胞系Lovo,通过Transwell侵袭小室实验检测癌细胞的侵袭能力,Western blot法检测癌细胞不同缺氧时点HIF-1α表达水平.结果 CatB转染组癌细胞穿透Transwell滤膜细胞数为(14.8±4.2),明显多于空载体转染组(8.6±3.7)和对照组(8.4±3.2)癌细胞(P<0.05).在缺氧0 时点,各组癌细胞无HIF-1α表达;缺氧6 时点HIF-1α仅有微量表达;在缺氧12 与24 时点,CatB转染细胞组HIF-1α表达水平明显提高,对照组和空载体转染组癌细胞HIF-1α表达水平无显著变化.比较同一缺氧时相,在缺氧0 与6 时点,各组癌细胞HIF-1α表达水平差异无统计学意义(P>0.05);在缺氧12 与24 时点,CatB转染组HIF-1α表达水平显著高于空载体组和对照组(P<0.01).结论 CatB可诱导结肠癌细胞HIF-1α表达,促进癌细胞对缺氧的适应并增强癌细胞的侵袭能力.     

Synchronous ipsilateral renal cell and transitional cell carcinoma

The coexistence of multiple and synchronous primary neoplasms in the genitourinary system has only rarely been described in the literature. We present the case of a 78-year-old man with haematuria as the initial presentation, finally proven to be transitional cell carcinoma (TCC) combined with renal cell carcinoma (RCC). Intravenous urography (IVU), CT and arterial angiography studies revealed a space-occupying nodule at the right upper renal pelvicalyces showing mild enhancement with contrast medium. Another strong contrast medium enhancing exophytic tumour was found at the lower pole of kidney; there were hypodense foci and calcified components in this lesion. A right nephroureterectomy was performed. Pathological diagnosis was a papillary TCC and a clear cell type RCC. This is a rare case of combined renal malignancies diagnosed by imaging.     

肾透明细胞癌与肾乳头状癌、嫌色细胞癌MRI表现的对照研究

目的 探讨MR动态增强扫描对肾癌亚型的鉴别诊断价值.方法 搜集77例经病理证实的肾癌患者资料,其中透明细胞癌(CCRCC)55例,乳头状癌(PRCC)14例,嫌色细胞癌(CRCC)8例,回顾性分析各亚型肿瘤患者MR平扫及动态增强扫描表现并与病理对照,根据肿瘤及肾皮质增强前后的皮质期、实质期及延迟期信号变化,分别进行百分比测量、肿瘤-肾皮质增强指数计算,并采用单因素方差分析和LSD法进行比较.结果 CRCC多数信号均匀(7/8);CCRCC及PRCC多数信号不均(分别为51/55和13/14)、常见坏死(36/55和7/14),PRCC最常见出血(9/14)及囊变(9/14).动态增强各期CCRCC强化程度最高,强化模式呈"快进快退",CRCC轻至中度强化,PRCC强化最轻,两者均呈渐进性延迟强化.CCRCC、PRCC及CRCC皮质期信号变化分别为(296.15±60.27)%、(79.70±18.84)%和(119.56±40.76)%,实质期分别为(236.33±58.31)%、(122.81±27.35)%和(163.06±33.91)%,延迟期分别为(216.83±46.72)%、(117.55±20.63)%和(179.72±32.89)%;三者皮质期的肿瘤-皮质增强指数分别为1.26±0.34、0.33±0.12及0.54±0.10,实质期分别为0.92±0.23、0.41±0.23及0.62±0.15,延迟期分别为0.76±0.14、0.35±0.11及0.69±0.12,各亚型增强各期的信号变化(F值分别为940.931、124.515、38.194,P值均＜0.01)、肿瘤-皮质增强指数(F值分别为798.625、78.308、73.699,P值均＜0.01)差异均有统计学意义.3种亚型的MRI表现与病理学所见基本相符.结论 CCRCC、PRCC及CRCC的MRI动态增强有一定特征性的表现,与其病理特点密切相关,在肾癌亚型的鉴别诊断上有着较高的临床应用价值.

Abstract：

Objective To investigate the differential diagnostic features of subtypes of renal cell carcinoma(RCC) using dynamic contrast-enhanced MRI(DCE-MRI).Methods The MRI appearances of 77 RCCs, including 55 clear cell RCCs(CCRCC),14 papillary RCCs(PRCC) and 8 chromophobe RCCs(CRCC), were retrospectively analyzed and compared with findings of pathology. DCE-MRI was conducted in each case after intravenous administration of contrast agent. Region of interest measurements (cortical, nephrographic and delayed Phases) of signals within tumor and uninvolved renal cortex were used to calculate percentage signal intensity change and tumor-to-cortex enhancement index, and the data was analyzed by AVONA and t test. Results On unenhanced and enhanced MRI, most CRCCs showed homogeneous signal(7/8). CCRCC and PRCC often show inhomogenous signal with necrosis(36/55, 7/14). Hemorrhage and cystic degeneration were often found in PRCC (9/14). On the cortical, nephrographic and delayed phase images, CCRCCs showed greater signal intensity change[(296.15±60.27)%, (236.33±58.31)% and (216.83±46.72)%,respectively than PRCCs (79.70±18.84)%, (122.81±27.35)% and (117.55±20.63)%, respectively], and CRCCs showed intermediate change [(119.56±40.76)%, (163.06±33.91)% and (179.72±32.89)%, respectively].A phenomenon of quick staining and quick fainting was observed in CCRCCs. Both of CRCCs and PRCCs showed delayed enhancement. The tumor-to-cortex enhancement index at the cortical, nephrographic and delayed phases was highest for CCRCCs (1.26±0.34, 0.92±0.23 and 0.76±0.14, respectively), lowest for PRCCs (0.33±0.12, 0.41±0.23 and 0.35±0.11, respectively), and intermediate for CRCCs (0.54±0.10, 0.62±0.15 and 0.69±0.12, respectively,P＜0.01). The degree of enhancement was significantly different among the 3 subtypes at the every contrast enhanced phase (F=940.931, 124.515 and 38.194, P＜0.01), so was the tumor-to-cortex enhancement index(F=798.625,78.308 and 73.699, P＜0.01). There was a good consistency between MR appearances of the 3 RCC subtypes and pathological characteristics. Conclusion DCE-MRI could distinctly show imaging features of CCRCC, PRCC and CRCC, which were related to their pathological characteristics, and these features were helpful in predicting a specific subtype of RCC.     

透明细胞乳头状肾细胞癌的影像学表现

目的探讨透明细胞乳头状肾细胞癌(CCPRCC)的影像学表现。方法分析15例CCPRCC患者CT及MRI影像特征,采用独立样本t检验比较肿瘤与肾皮质之间平扫CT值、ADC值差异。结果15例均为单发,边界清晰,大小为(3.1±1.9)cm。13例为实性肿瘤,其中11例伴囊变,2例为囊性肿瘤。4例CT平扫呈等或稍低密度,4例呈稍高密度;6例密度不均匀,1例伴细条状钙化;8例CT值为(38.4±10.6)HU,与肾皮质比较差异无统计学意义(P>0.05)。8例MRI平扫T1WI呈稍低或低信号,3例伴发结节状、灶状高信号;8例T2WI以混杂高信号为主,5例边缘见包膜;7例DWI呈稍高信号;9例肿瘤ADC值(2.22±0.30)×10-3 mm2/s高于肾皮质,两者差异具有统计学意义(P<0.05)。增强扫描13例实性肿瘤中9例呈“快进快出”强化,4例呈持续或渐进性强化;2例囊性肿瘤增强扫描呈囊壁及中心分隔强化。结论CCPRCC好发于中老年人,肿瘤易发生囊变,出血、钙化少见,弥散受限不明显,增强扫描以“快进快出”强化为主,确诊仍需依靠组织病理学。     

Fluorodeoxyglucose cell incorporation as an index of cell proliferation: evaluation of accuracy in cell culture

The use of fluorodeoxyglucose (FDG) and positron emission tomography (PET) is recognized as an accurate tool for the specific diagnosis and staging of cancer. It has also been proposed for the monitoring of anticancer therapy. FDG cell incorporation reflects glycolytic activity whereas inhibition of cell proliferation corresponds to an efficient cancer treatment. The relationship between FDG incorporation and cell proliferation has yet to be demonstrated. Therefore, we aimed to correlate the effects of the toxic agents bleomycin and unlabelled meta-iodobenzylguanidine (mIBG) on cellular metabolism and proliferation. We determined the in vitro metabolic and cytotoxic effects of bleomycin and mIBG by measuring the incorporation of fluorine-18 FDG (%U_FDG) and hydrogen-3 thymidine (%U_THY) in cells of the human premonocytic line U937 in the presence of increasing concentrations of these agents. Proliferation rate of these cells was studied by means of limiting dilution analysis. %U_THY appeared more sensitive to bleomycin or mIBG-mediated cell injury than %U_FDG. After 1 h of exposure to 0.5 M bleomycin, %U_THY was significantly reduced to 62.0% ± 10.4% of control value whereas %U_FDG remained unchanged (91.6% ± 5.3%). Similar results were obtained after 1 h of exposure to increasing concentrations of mIBG (1 M to 1 mM). After 20 h of exposure to bleomycin, %U_THY and %U_FDG were significantly reduced as a function of concentration. After 20 h of exposure to mIBG, a transient increase in %U_FDG up to 149.3% ± 11.2% with 50 M mIBG was further followed by a reduction to 20.1% ± 6.7% with 0.5 mM (P < 0.001). The clonogenic efficiency was reduced as a function of bleomycin (ANOVA, n=255, P) or mIBG concentration (n=80, P) and nearly abolished with 0.1 M bleomycin or 0.1 mM mIBG. In conclusion, %U_THY appears to be a more sensitive index of cytotoxicity in vitro and more accurately relates to cell proliferation than %U_FDG. Correspondence to: D.O. Slosman, Nuclear Medicine Division, Geneva University Hospital, CH-1211 Geneva 14, Switzerland     

一种改进的用于测定细胞周期的细胞制备方法

目的 :减少细胞的聚集数量 ,提高测试效率和结果的准确性。方法 :在用酒精固定细胞时分别加入终浓度为 0 % ,1.5 % ,3% ,6 %和 12 %的小牛血清 ,置 - 2 0℃分别固定细胞 1d ,3d和 7d。比较了不同浓度的血清和保存不同时间粘连细胞的数量及对细胞周期分析结果的影响。结果 :加入血清可明显减轻细胞的粘连 ,减少了细胞的聚集数量 ,尤以 3%小牛血清组最佳。样品可不必过滤 ,在上机测试时 ,进样针不堵塞 ,上样速度快 ,细胞周期分析更准确。随着保存时间的延长 ,聚集细胞的数量有增加的趋势。结论 :在制备用于测定细胞周期的样品时 ,固定细胞的过程中加入终浓度为 3%的小牛血清是一种简单的、能有效地保护细胞膜使细胞不易粘连的技术措施 ,且固定细胞的时间不宜超过 7d。     

Clear cell chondrosarcoma

The clinical, radiologic, and histopathologic features of three cases of clear cell chondrosarcoma are described. On radiographs, this rather benign-appearing tumor resembles a chondroblastoma when it occurs at the end of a long bone, and may occasionally show a calcified matrix. However, it has distinctive tumor cells with a centrally placed vesicular nucleus surrounded by clear cytoplasm. The lesion has a low-grade malignancy and is amenable to en bloc surgical resection, which results in a much better prognosis than that of conventional chondrosarcoma.