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71.
以无细胞核的兔网织红细胞与小鼠骨髓瘤细胞BW(胸腺淋巴肉瘤)及SP2/0(浆细胞瘤)分别进行异种杂交。实验结果表明杂交后形成的二种胞质杂交细胞(BW-RR及SP 2/0-RR)均呈现下列去恶性分化特征;①细胞分裂指数、~3H-TdR标记指数及生长曲线明显下降。其中SP2/0-RR的核分裂活动受到明显的抑制;②在软琼脂培养中不形成集落;③异种移植至裸鼠不长瘤;④染色体数量减少,众数及畸变率下降;⑤出现正常分化的珠蛋白基因产物血红蛋白和HGPRT基因的酶产物,珠蛋白探针分子杂交实验证明有珠蛋白基因的表达。为不同种属红细胞胞质因子调控肿瘤细胞恶性提供了证据。论文对胞质因子调控基因表达、恶性逆转及其在红细胞发生过程中自然去核的物质基础等问题进行了讨论。 相似文献
72.
目的 :手术室为了使实践教学能够有计划、有组织、科学地、系统地、有效地进行 ,实行把教学作为一项系统工程进行设计和实施。使教学活动的过程依照传授知识 -掌握知识 -运用知识 (教 -学 -做 )的模式来完成。方法 :通过对实习对象的分析 ,制定临床带教计划 ,实施计划 ,评估与反馈等方法 ,让学生们全面参与手术室专业临床护理实践。结果 :把所学的理论和技能正确运用于实际工作中 ,以巩固和充实理论知识 ,进一步获得和掌握手术室护理专业技能。结论 :培养科学的思维能力、严谨的工作作风、良好的职业道德 相似文献
73.
Sutter TR He XR Dimitrov P Xu L Narasimhan G George EO Sutter CH Grubbs C Savory R Stephan-Gueldner M Kreder D Taylor MJ Lubet R Patterson TA Kensler TW 《Molecular cancer therapeutics》2002,1(14):1283-1292
Microarray technology has greatly aided the identification of genes that are expressed differentially. Statistical analysis of such data by multiple comparisons procedures has been slow to develop, in part, because methods to cluster the results of such comparisons in biologically meaningful ways have not been available. We isolated and analyzed, by Northern blot and GeneChip, replicate liver RNA samples (n = 4/group) from rats fed with control diet or diet containing one of three chemopreventive compounds, selected because their pharmacological activities, including RNA expression response, are relatively well understood. We report on a classification tree, based on the results of nonparametric multiple comparisons, which results in the bipolar hierarchical clustering of genes in relation to their response to treatment. In addition to identifying treatment-responsive genes, application of this procedure to our test study identified the known pharmacological relationships among the treatment groups without supervision. Also, small treatment-specific subsets of genes were identified that may be indicative of additional pharmacophores present in the test compounds. 相似文献
74.
目的:构建含融合基因anti-erbB2 scFv-Fc-CD28-CD3(ζ)的T细胞株,为erbB2过度表达肿瘤的靶向基因治疗奠定实验基础。方法:利用SWISS MODEL和PHYRE预测该融合蛋白的三级结构。利用PCR分别从重组质粒pPIC9k、pBullet和pLNCX上扩增出3段基因片段,即片段anti-erbB2 scFv、片段Fc-CD28-CD3(ζ)和信号肽序列signal。利用SOE-PCR将3段序列连接形成融合基因片段signal-anti-erbB2 scFv-Fc-CD28-CD3(ζ)。经TA克隆扩增及鉴定后,将融合基因片段与逆转录病毒表达载体pLNCX相连构建重组真核表达载体,脂质体方法转染人T淋巴细胞株Jurkat,G418筛选后用流式细胞术检测融合蛋白稳定表达情况。结果:经预测该融合蛋白在三级结构上可形成功能构象。经PCR、酶切及测序鉴定均证实成功构建重组真核表达载体pLNCX/signal-anti-erbB2 scFv-Fc-CD28-CD3(ζ)。经流式细胞术检测,在Jurkat细胞中表达量达23.68%。结论:应用分子克隆的方法成功地构建了重组真核表达载体pLNCX/anti-erbB2 scFv-Fc-CD28-CD3(ζ),融合基因能够在T淋巴细胞株中表达,为制备含该融合基因的原代T淋巴细胞,进行erbB2过度表达肿瘤的靶向基因治疗研究奠定了基础。 相似文献
75.
Chen H Zhu Q Tang X Min M Jie L Chen L 《African journal of traditional, complementary, and alternative medicines》2011,8(4):467-476
The aim of this study is to investigate the effect of Shen-qi-di-huang decoction on reducing proteinuria and to discuss the mechanism of its action in Adriamycin (ADR)-induced nephropathy rats. The rats were randomly divided into three groups (n=12 each group): normal control (group A); ADR model control (group B); ADR + Shen-qi-di-huang decoction (group C). In group B and C, the rats were intravenously injected with ADR (6.5mg/kg). The rats in group C were orally administrated with Shen-qi-di-huang decoction after the injection of ADR. On day 7, 14, 28, 56 after ADR injection, 24h urine protein was detected. On day 28, 56 after ADR injection, ALB, ALT, serum creatinine (Scr) and BUN were examined. The morphological changes of the kidneys were observed by light microscope and electron microscope on day 28, 56 after ADR injection. The expression of nephrin was determined by immunohistochemistry and RT-PCR on day 28, 56 after ADR injection. Compared with group B, 24h urine protein and Scr decreased in group C on day 56 (P<0.05). The expression of nephrin determined by immunohistochemistry and RT-PCR increased in group C on day 28, 56 (P<0.05). The morphology observed by light microscope and electron microscope improved in group C on day 28, 56. Shen-qi-di-huang decoction decreases proteinuria, protects kidney function, and ameliorates histopathology in ADR-induced rats by preserving nephrin expression. 相似文献
76.
Luo L Zeng J Liang B Zhao Z Sun L Cao D Yang J Shen K 《Experimental and molecular pathology》2011,(2):596-602
Cancer stem cells (CSCs) play an important role in the recurrence and drug resistance of cancer. Isolation and characterization of CSCs from ovarian cancer samples may help to provide novel diagnostic and therapeutic targets in the management of recurrent disease and drug resistance in ovarian cancer. Here, we developed a xenograft model in which cells from 14 samples of human ovarian serous adenocarcinoma tissue or ascites were implanted in immunodeficient mice to test the tumorigenic potential of different populations of ovarian cancer cells. We identified and isolated the tumorigenic cells as CD117+Lineage− from three different xenografts. As few as 103 cells with the CD117+Lineage− phenotype, which comprise < 2% of the xenograft tumor cells, were able to regenerate tumors in a mouse model, a 100-fold increase in tumorigenic potential compared to CD117−Lineage− cells. The tumors that arose from purified CD117+Lineage− cells reproduced the original tumor heterogeneity and could be serially generated, demonstrating the ability to self-renew and to differentiate, two defining properties of stem cells. Furthermore, immunohistochemistry analysis of 25 patients with advanced ovarian serous adenocarcinoma revealed positive immunostaining for CD117 in 40% (10 of 25) of patients. CD117 expression was statistically correlated with resistance to conventional chemotherapy (P = 0.027). In conclusion, our study demonstrates that human ovarian cancer cells with the CD117+ phenotype possess the unique properties of CSCs, including self-renewal, differentiation, a high tumorigenic potential, and chemoresistance. Future studies designed to target CD117+ cancer cells may identify more attractive and effective therapies for treatment of ovarian cancer. 相似文献
77.
机体运动时伴随ATP需求增加、有氧和无氧代谢增强,其结果是ROS生成增加, 但研究证明规律运动可降低一些与ROS有关的疾病发生率,运动对这些疾病的预防作用一定程度是由于机体对氧化应激产生了适应.其分子机制是体内抗氧化物和一些基本的氧化损伤修复酶活性的增加,对氧化攻击抵抗能力的增强,并且这一变化是系统性的、全身性的.骨骼肌、肝脏和脑这些器官虽然在运动过程中的代谢特点和功能完全不同,但它们的适应反应却非常相似:由于氧化还原稳态的改变,体内抗氧化酶、DNA修复酶和蛋白酶体复合物的活性增加,使氧化损伤水平降低、对氧化应激的抵抗力增强等.因而,运动促进健康的作用其机制可能就是运动可使机体具有较高的抵抗ROS的水平. 相似文献
78.
非体外循环冠状动脉旁路移植术的麻醉和围术期管理 总被引:1,自引:0,他引:1
非体外循环冠状动脉旁路移植术(off—pumpcoronaryarterybypassgrafting,OPCAB),减少了与体外循环(ECC)有关的并发症,如全身炎症样反应,凝血系统障碍继发术后出血,神经系统并发症,脏器灌注不足引起心、肺、脑、肾多器官功能不全等,降低了对机体的生理干扰,术后恢复快,其安全性和有效性已得到临床实践的证明。但是,由于OP—CAB需要在心脏不停跳,没有体外循环的情况下进行,因此手术的特殊性增加了麻醉的难度和要求,我们总结分析了18例实施OPCAB的患者的麻醉和围术期管理,现报告如下。 相似文献
79.
目的:建立一点红不同营养器官中总黄酮和总酚含量测定方法。方法:以芦丁为对照品,采用NaNO2-Al(NO3)3-NaOH比色法测定了总黄酮含量;以没食子酸为对照品,采用Folin-Ciocalteu比色法测定了总酚含量。结果:芦丁浓度在0.01~0.08mg/ml范围内与吸光度呈良好线性关系,平均加样回收率为100.30%,RSD=1.72%,一点红叶、茎、根中总黄酮含量分别为2.54%、1.78%、1.27%;没食子酸浓度在0.002~0.010mg/ml范围内与吸光度呈良好线性关系,平均加样回收率为99.86%,RSD=1.92%,一点红叶、茎、根中总酚含量分别为21.28%、12.77%、8.51%。结论:这2种方法灵敏,准确性强,精密度高,重复性好,可以用作一点红中总黄酮和总酚含量的测定。 相似文献
80.
涎腺肌上皮瘤的临床病理分型和免疫组化研究 总被引:10,自引:0,他引:10
对从1873例涎腺肿瘤复查后确诊的43例涎腺肌上皮瘤进行了临床病理学和免疫组化研究。结果显示:该瘤的患病率约占涎腺肿瘤的2.3%,好发于腮腺(48.84%)和腭腺(41.86%);该瘤在病理上可分为5型:即上皮细胞型、梭形细胞型、浆细胞样细胞型、透明细胞型和混合细胞型,其实质细胞——肿瘤性肌上皮细胞为一个连续变化的瘤细胞谱,各种形态的瘤细胞可以互相转化;免疫组化CK-18、actin染色显示上述各型瘤细胞均为程度不等的阳性。作者认为提高该瘤确诊率的关键是对各型瘤细胞的认识;联合应用CK-18、actin有助于该瘤的诊断和与多形性腺瘤的鉴别。 相似文献