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目的:探讨CD40/CD40配体结合产生的共刺激信号对干细胞、B细胞增殖分化的影响及CD40配体抗白血病的作用。资料来源:检索Pubmed和Springer数据库1995-01/2005-12与CD40/CD40配体、白血病干细胞及白血病相关文献,检索词为“CD40,CD40L,Leukemia,Leukemicstemcell”,限定文献语种为英语。资料选择:对资料进行初审,选取实验包括实验组和对照组的文献,排除明显不随机实验和临床研究及重复性研究。资料提炼:共收集到30篇关于CD40/CD40配体结合产生的共刺激信号对干细胞、B细胞增殖分化的影响及CD40配体抗白血病作用的实验文章,23篇符合纳入标准,排除的7篇均为同一研究。资料综合:综合23个实验包括CD40/CD40配体对白细胞干细胞、B细胞增殖分化的影响,对白血病患者预后的影响及CD40配体对白血病患者的治疗作用,并对CD40/CD40配体对白细胞干细胞、B细胞及白血病患者的影响、作用进行分析。结论:CD40/CD40L结合所产生的共刺激信号可促进白血病干细胞和B细胞的增殖分化,与白血病的发生、发展和预后有密切关系。CD40/CD40L在免疫应答中起关键作用,广泛应用于白血病的免疫治疗。 相似文献
64.
Sonographic and Doppler imaging in the diagnosis and treatment of gestational trophoblastic disease: a 12-year experience. 总被引:5,自引:0,他引:5
OBJECTIVE: To evaluate the clinical utility of sonography with Doppler examination in the diagnosis and treatment of gestational trophoblastic disease (GTD). METHODS: A retrospective analysis of 355 cases of GTD seen over a 12-year period in 2 large university referral hospitals in China was performed. Clinical appearances, sonographic findings, Doppler waveforms, and patient outcomes were reviewed. Sonographic and Doppler examinations were performed to diagnose the presence of molar tissue, detect invasive disease, assess disease recurrence, and monitor the efficacy of chemotherapy. Doppler waveforms of 13 patients with normal early pregnancies were also examined for comparison. RESULTS: Of the 355 patients with GTD, 106 had a classic hydatidiform mole (CHM), 33 had a partial hydatidiform mole (PHM), 184 had an invasive hydatidiform mole (IHM), and 32 had choriocarcinoma. Sonography showed abnormal molar tissue confined to the endometrial cavity in all cases of CHM. In cases of IHM and choriocarcinoma, soft tissue invasion and cystic vascular spaces within the myometrium were shown. Cases of PHM had a thickened, hydropic placenta with a concomitant fetus. Doppler waveforms showed resistive indices of 0.55 (SD, 0.06) for CHM, 0.56 (SD, 0.04) for PHM, 0.28 (SD, 0.06) for IHM, 0.25 (SD, 0.05) for choriocarcinoma, and 0.66 (SD, 0.04) for normal pregnancies. The abnormal sonographic and Doppler findings in invasive disease resolved when chemotherapy was successful. CONCLUSIONS: Sonography and Doppler imaging were helpful in diagnosing GTD, in determining whether invasive disease was present, in detecting recurrence of disease, and in following the effectiveness of chemotherapy. 相似文献
65.
本研究旨在探索鼠巨细胞病毒(MCMV)在小鼠骨髓单个核亚群细胞中的感染特性。采用免疫磁珠分选法(MACS)分选小鼠骨髓单个核亚群细胞,包括lin+细胞、lin-细胞、lin-CD117+和lin-CD117-细胞;用MCMV攻击分选的各组分细胞并以细胞因子和诱导剂诱导细胞分化,最后检测病毒核酸及相关蛋白。结果表明:在MCMV感染的lin+细胞中可检测到病毒DNA和立即早期基因的转录产物及其蛋白,而在感染的lin-细胞中则未检测到任何病毒产物。通过添加细胞因子GM-CSF、rhEPO或佛波酯,则可以在感染的lin-细胞中检测到MCMV的立即早期和早期基因转录产物以及蛋白表达。在lin-CD117+和lin-CD117-细胞中也未检测到病毒基因转录产物,但MCMV感染可抑制lin-CD117+造血干/祖细胞集落的形成以及下调其表面标志CD117抗原的表达。结论:MCMV可在小鼠骨髓单个核亚群细胞中潜伏感染;小鼠骨髓中具有原始干/祖细胞性质的细胞群对MCMV不易感,但MCMV感染可对这些细胞的功能产生抑制作用,可使细胞表面标志表达下调。 相似文献
66.
目的:通过对汗腺发生、形态、结构以及神经支配和汗液产生及汗腺细胞电生理实验的归纳总结,加深对汗腺再生与重建理论依据的认识。资料来源:应用计算机检索Medline1990-01/2005-01与汗腺发生、形态、结构以及神经支配及汗液产生机制的相关文章,检索词“sweatgland,structure,function”,并限定文章语种为English。同时计算机检索清华全文期刊数据库1990-01/2005-01与汗腺发生、形态、结构、神经支配及汗腺细胞电生理实验的相关文章,检索词“汗腺、发生、结构、功能”,限定语种为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:文章所述内容应与汗腺发生、形态、结构、神经支配及汗液产生相关。排除标准:重复研究或Meta分析类文章。资料提炼:共收集到510篇相关文献,140篇文献符合纳入标准,排除的370篇文献是由于内容陈旧或重复。资料综合:140篇文献中,86篇涉及汗腺发生、形态与结构,31篇涉及汗腺的神经支配,23篇涉及汗液产生及汗腺细胞电生理实验。①汗腺的发生是一个非常复杂的过程,有赖于表皮基底膜区的生理性稳定与真皮-表皮间的相互作用,是基质金属蛋白酶-2和基质金属蛋白酶-7与细胞外基质、表皮生长因子共同协调作用作用的结果。②汗液从汗腺的分泌部分泌时为近等渗液,流经导管时,钠、氯和一些水分被重吸收,使汗液的成分发生变化,最终以低渗液从皮肤表面排出。③汗腺导管细胞和分泌细胞具有不同的电生理现象,正常状态下分泌细胞静息膜电位明显高于导管细胞。④大量体外实验成功分离并培养了汗腺的导管细胞、分泌细胞以及肌上皮细胞,并对其形态发生、生长调控及分化与功能进行探讨以期重建汗腺。结论:由于表皮干细胞与汗腺在发育学上有共同的起源,有可能利用表皮干细胞向汗腺细胞定向分化,从而再生汗腺。另外大面积烧伤患者仍有部分残留的汗腺,有可能通过加速汗腺再生速度和消除瘢痕组织中的屏障因素来重建汗腺。 相似文献
67.
从2型糖尿病健康教育团队的组成、教育模式、教育内容(2型糖尿病的危害、预防、饮食、运动、心理、药物及血糖监测的护理)及效果评价概括2型糖尿病健康教育的研究进展,归纳总结出2型糖尿病健康教育中存在的不足,并提出相关对策,以提高2型糖尿病健康教育的质量。 相似文献
68.
目的 :探讨彩色多普勒超声 (CDFI)筛选适合药物保守治疗异位妊娠的临床价值。方法 :4 8例生命体征平稳的异位妊娠患者 ,在行CDFI检查后接受甲氨喋呤 (MTX) 5 0mg/m2 单次肌肉注射配合口服米非司酮 15 0mg ,随访直至临床结局。分析成功与失败病例CDFI的特点和绒毛膜促性腺激素 (hCG)水平 ,并制作CDFI评分。结果 :CDFI能直接反映胚胎生命力 ,CDFI图像和血清hCG水平不同者 ,保守治疗成功率有很大差异。结论 :CDFI评分可应用于适合保守治疗异位妊娠病例的筛选。对评分 >9者因失败率高 ,不推荐药物保守治疗。 相似文献
69.
Felipe L. Schiffino Vivian Zhou Peter C. Holland 《The European journal of neuroscience》2014,39(4):640-649
Within most contemporary learning theories, reinforcement prediction error, the difference between the obtained and expected reinforcer value, critically influences associative learning. In some theories, this prediction error determines the momentary effectiveness of the reinforcer itself, such that the same physical event produces more learning when its presentation is surprising than when it is expected. In other theories, prediction error enhances attention to potential cues for that reinforcer by adjusting cue‐specific associability parameters, biasing the processing of those stimuli so that they more readily enter into new associations in the future. A unique feature of these latter theories is that such alterations in stimulus associability must be represented in memory in an enduring fashion. Indeed, considerable data indicate that altered associability may be expressed days after its induction. Previous research from our laboratory identified brain circuit elements critical to the enhancement of stimulus associability by the omission of an expected event, and to the subsequent expression of that altered associability in more rapid learning. Here, for the first time, we identified a brain region, the posterior parietal cortex, as a potential site for a memorial representation of altered stimulus associability. In three experiments using rats and a serial prediction task, we found that intact posterior parietal cortex function was essential during the encoding, consolidation, and retrieval of an associability memory enhanced by surprising omissions. We discuss these new results in the context of our previous findings and additional plausible frontoparietal and subcortical networks. 相似文献
70.
Lingling Kong MD Jian Cheng MD Xiuping Ding MD Baosheng Li MD PhD Jian Zhang PhD Hongsheng Li PhD Wei Huang PhD Tao Zhou MD Hongfu Sun MD 《The breast journal》2014,20(2):116-124
To compare the treatment outcomes between accelerated partial breast irradiation (APBI) and conventional whole‐breast irradiation (WBI) and to explore the efficacy and safety of APBI as an adjuvant treatment for early‐stage breast cancer who received breast‐conserving therapy. Eligible studies were identified on Medline, Embase, and the Cochrane Library updated to July 10, 2012. Comparative studies were considered for inclusion. Analyses were carried out using Stata software. Eleven comparative studies with a total of 7,097 patients were included. The meta‐analysis showed that there were no statistically significant differences between group APBI and group WBI associated with the supraclavicular failure, distant metastasis, overall survival, and disease‐free survival, while local recurrence (LR) and axillary failure (AF) increased in group APBI. The sensitivity analysis indicated that both the LR and AF were not statistically significant difference between the two groups. In the subgroup analysis, LR was statistically significantly higher in group APBI for patients with the age <60, large tumor size, and unknown margin status. APBI is a safe treatment modality and could become a potential option for the delivery of adjuvant radiation therapy in patients receiving breast‐conserving therapy, especially for the suitable group that was classified by the American Society of Radiation Oncology Consensus Panel. 相似文献