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51.
The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment.  相似文献   
52.
Sensitivity of cervical cytology is suboptimal, especially in developing countries such as Mexico, despite available guidelines aimed at improving this. When obtaining cervical samples, whether the samples are taken from the transformation zone and whether abnormal cells are missing must be considered. Cervical secretions (CS) are always present in variable proportions, and when cleaning the cervix, better samples may be obtained. In this study, we analyzed samples obtained with or without cleaning the cervix, and compared their contents in order to determine the sensitivity and specificity of these two methods. Methods: Of 500 patients who underwent cytology and colposcopy, 271 (54.2%) required a second opinion due to a diagnosis of cervical intraepithelial neoplasia (CIN). CS was removed and compared with the clean, second sample (SS) using in both liquid-based cytology. The quality of samples according to the Bethesda System, the presence of CIN, and inflammatory reactions were recorded. The sensitivity and specificity were calculated using biopsy as the gold standard. Results: The SS resulted in a higher proportion of adequate samples being obtained (97.6% vs. 44.8%), and in increased sensitivity (88.2% vs. 58.8%). CIN was detected in the SS 26% more often than in the CS (34 vs. 27 samples), whereas inflammatory reactions were noted more often in the CS (91.4% vs. 74%). Conclusion: Cervical sampling including CS results in lower sensitivity and CIN detection rates, and in more inflammatory reactions. By excluding CS from cervical samples, the sensitivity could be improved and the false negative rate could be reduced.  相似文献   
53.
目的:在成功分离人皮肤角质形成细胞的基础上,观察表皮生长因子受体在人皮肤角质形成细胞中的表达情况。方法:实验于2006-3/10在北京大学深圳医院中心实验室进行。采用dispase Ⅱ-trypsin两步消化法获取表皮基底层细胞,用小鼠皮肤成纤维母细胞滋养层和黄素腺嘌呤二核苷酸培养液进行培养。小鼠皮肤成纤维母细胞的预处理:向对数生长期的小鼠皮肤成纤维母细胞培养液中加入丝裂霉素C至终浓度为4mg/L,37℃下培养4h,弃去培养液,用D-Hank’s液洗3次,加入浓度为0.25g/L的胰蛋白酶消化,分离出细胞,离心(200g,5min),用黄素腺嘌呤二核苷酸培养液悬浮细胞,计数,以5.0×104/cm2的密度种于培养皿内,37℃、体积分数0.05的CO2培养箱下培养。角质形成细胞的培养:将分离的角质形成细胞悬浮在黄素腺嘌呤二核苷酸培养液中,以2.0×104/cm2的密度接种在前1天经丝裂霉素C处理的小鼠皮肤成纤维母细胞滋养层上,37℃、体积分数0.05的CO2培养箱下培养。24h换液,以后每3d换1次液。采用免疫细胞化学的方法检测表皮生长因子受体的表达,采用复合逆转录聚合酶链反应检测角质形成细胞中表皮生长因子受体mRNA的表达。结果:采用dispaseⅡ消化法分离了真皮和表皮,获得较多的角质形成细胞,可以避免真皮成纤维细胞的污染。人皮肤角质形成细胞在黄素腺嘌呤二核苷酸培养液中培养5d可见明显的集落,约10d可长满单层。免疫细胞化学显示表皮生长因子受体在细胞表面有明显的表达,复合逆转录聚合酶链反应显示表皮生长因子受体mRNA有明显的表达。结论:用小鼠皮肤成纤维母细胞滋养层和黄素腺嘌呤二核苷酸培养液可以较好地培养原代人皮肤角质形成细胞,表皮生长因子受体在细胞表面有明显的表达,这些结果为与表皮生长因子受体相关的皮肤病(如银屑病)的研究奠定了基础。  相似文献   
54.
目的:一些理论质疑富血小板血浆对骨前体细胞成骨分化的作用,本实验拟验证富血小板血浆对体外培养的人骨髓间充质干细胞成骨分化的抑制效应。方法:实验于2005-05/11在南方医科大学组织工程试验室(省级)完成。①实验方法:抽取6名健康志愿者髂前上棘骨髓5mL进行体外细胞培养扩增,静脉血10mL以二次离心法制得富血小板血浆。诱导骨髓间充质干细胞时富血小板血浆与骨髓间充质干细胞均来自同一个体。②碱性磷酸酶染色:取第4代骨髓间充质干细胞,分为两组:富血小板血浆组加入富血小板血浆使终浓度为100g/L,单纯血清培养组仅加入等量胎牛血清。培养后第7天进行碱性磷酸酶染色,阳性细胞为胞质中呈现黑色颗粒或块状沉淀。③矿化结节染色:取第4代骨髓间充质干细胞,分组同上。培养后第19天以0.1%茜素红-TrisHcl(pH8.3)37℃下放置30min,矿盐沉积染色阳性为红色。④Cbfa1基因表达:取第4代骨髓间充质干细胞,分组同上。培养后第3,7,12,16天RT-PCR法检测骨髓间充质干细胞Cbfa1基因的表达。⑤形态学观察:实验过程中使用相差显微镜观察各组细胞生长情况及形态学变化。结果:①骨髓间充质干细胞碱性磷酸酶染色结果:培养后第7天,富血小板血浆组碱性磷酸酶阳性细胞数量较单纯血清培养组明显减少,且阳性细胞内灰黑色颗粒也明显减少,为弱阳性。②骨髓间充质干细胞矿化结节染色结果:培养后第19天,单纯血清培养组可见细胞表面有较多的矿盐沉积,但未形成明显的矿化结节。富血小板血浆组细胞表面只有稀少的矿盐沉积。③骨髓间充质干细胞cbfa1mRNA的表达:培养后第3,7,12,16天,随着培养时间的延长单纯血清培养组与富血小板血浆组cbfa1基因表达量均逐渐增高,同一时间点两组间cbfa1基因的表达基本相似。④骨髓间充质干细胞形态学变化:富血小板血浆组骨髓间充质干细胞增殖旺盛,细胞达到单层汇合的时间较单纯血清培养组明显缩短。单纯血清培养组细胞在完全汇合后开始出现聚合现象(14~16d),但趋向性不明显,未完全形成团簇;富血小板血浆组细胞在完全汇合后未出现聚合现象,细胞密集生长。培养初期两组细胞以梭形为主,多角形细胞较少,培养至14~16d单纯血清培养组多角形细胞较富血小板血浆组增多。结论:富血小板血浆可抑制人骨髓间充质干细胞碱性磷酸酶的分泌与矿盐沉积,对人骨髓间充质干细胞成骨分化的直接效应是抑制其分化。  相似文献   
55.
目的:肝脏可溶性复合物具有保护肝脏、刺激肝组织再生等生物学活性,观察天然物质肝脏可溶性复合物对肿瘤细胞生长增殖的抑制作用.方法:实验于2006-05/2007-02在四川大学华西医院生物治疗国家重点实验室实验肿瘤研究室完成.①分离人胚胎、成年及新生小鼠肝脏组织,生理盐水清洗、剪碎、筛网过滤,用生理盐水制备混悬液,3 000 r/min离心,收集上清,制备肝脏可溶性复合物.②体外实验:用上述不同来源的肝脏可溶性复合物体外处理肿瘤细胞,四甲基偶氮唑盐比色法测定其对乳腺癌细胞EMT6增殖的影响.③体内实验:观察成年鼠肝脏可溶物质对乳腺癌细胞EMT6体内生长的抑制作用及其对荷瘤鼠生存状况的影响,包括不同给药剂量及不同给药途径两个实验,给药途径包括在接种肿瘤细胞部位的对侧腋下、同侧腋下、腹腔注射及灌胃等.结果:①体外实验显示不同来源的肝脏可溶性复合物能明显抑制肿瘤细胞EMT6增殖率,肿瘤增殖抑制率均显著高于血清白蛋白处理组(P<0.05),并呈剂量依赖性.②成年鼠肝脏可溶物质8mg/L组抑瘤率高于2,4 mg/L组(P<0.05),未观察到明显毒副效应.③比较不同给药途径,成年鼠肝脏可溶物质同侧注射组的抑瘤率较其他3组的抑瘤率高(P<0.05),各成年鼠肝脏可溶物质给予组的体质量增长率比相应生理盐水对照组高(P<0.05).④与相应生理盐水对照组比较,在同侧腋下注射成年鼠肝脏可溶物质的小鼠生存期明显延长(P<0.05).结论:肝脏可溶性复合物具有抑制肿瘤细胞生长的作用,并且呈一定的剂量依赖性.不同的给药途径中,在接种肿瘤细胞部位的同侧腋下给药抑瘤效果最好.  相似文献   
56.
目的:调查了解山东泰安地区农村人群的血脂水平,为该地区农民心脑血管疾病的预防提供基础数据。方法:实验于2006-06随机选取泰安市两个自然村650人进行健康检查,男270人,女380人,年龄2~88岁。①650人均于早晨空腹采集静脉血3mL,静置凝固后,2h内分离血清,采用全自动生化分析仪常规测定患者血脂指标总胆固醇、三酰甘油水平。②总胆固醇>5.2mmol/L判定为高胆固醇血症,三酰甘油>1.7mmol/L判定为高三酰甘油血症。结果:650人全部完成血样采集与血脂指标检测。①不同性别血脂水平比较:被检人群男性三酰甘油水平显著高于女性[(1.16±1.47),(0.95±0.84)mmol/L,P<0.05];男女总胆固醇水平基本相似(P>0.05)。②不同年龄段血脂水平比较:8人因具体年龄段不祥被排除,剩余642人分为3个年龄段:2~30岁、31~50岁、51~88岁。结果31~50岁人群三酰甘油水平显著高于2~30岁人群[(1.14±1.47),(0.88±0.70)mmol/L,P<0.05],略高于51~88岁人群(P>0.05);51~88岁人群总胆固醇水平>31~50岁人群>2~30岁人群,相邻年龄段间比较差异均有显著性意义(P<0.001)。③各年龄段男女间血脂水平比较:2~30岁人群和51~88岁人群三酰甘油水平性别间差异均无显著性意义(P>0.05),但总胆固醇水平女性均显著高于男性[(2.38±1.47),(1.85±1.26)mmol/L,P<0.05;(4.48±0.92),(4.18±0.76)mmol/L,P0.01]。31~50岁人群男性三酰甘油水平显著高于女性[(1.51±2.06),(0.90±0.80)mmol/L,P<0.01],总胆固醇水平基本相似(P>0.05)。④各年龄段男女高血脂症构成比:31~50岁人群高三酰甘油血症构成比显著高于2~30岁、51~88岁人群(23.1%,5.5%,9.3%,P<0.01);随着年龄增高,各年龄段高胆固醇血症构成比逐渐升高,相邻年龄段间差异均有显著性意义(2.7%,8.6%,15.6%,P<0.01)。31~50岁人群男性高三酰甘油血症、高胆固醇血症的构成比显著高于女性(P<0.01);2~30岁、51~88岁人群男女间高血脂症的构成比基本相似(P>0.05)。结论:①山东泰安地区农村人群高三酰甘油血症,31~50岁年龄段患病率最高;高胆固醇血症患病率随年龄增长逐步上升,提示中年人健康体检尤为重要。②高脂血症应从青少年开始加大预防和保健力度,进行广泛和反复的健康教育,倡导健康的生活方式和生活行为。  相似文献   
57.
恶性肿瘤淋巴管生成与转移的研究进展   总被引:1,自引:0,他引:1  
张海娥  庄建基  杨帆 《医学争鸣》2007,28(5):479-480
淋巴道转移是肿瘤转移的重要途径,也是判断预后的重要依据. 随着淋巴管生成因子及许多淋巴管特异性标记物的发现,肿瘤新生淋巴管调控与淋巴道转移机制研究得以深入开展. 大量的研究发现,恶性肿瘤和瘤周组织内存在新生的淋巴管,新生的淋巴管密度和淋巴管标记物的表达强度均与淋巴结转移密切相关. 这为揭示恶性肿瘤淋巴道转移机制和开发淋巴管靶向治疗提供了重要的研究途径. 现就近年来肿瘤淋巴管生成与转移的研究进展作一综述.  相似文献   
58.
Background Post‐inflammatory hyperpigmentation (PIH) is a common occurrence in patients with acne vulgaris, particularly in those with skin of colour. Aims A previous study has demonstrated the benefit of tretinoin (retinoic acid) in the treatment of PIH; however, there is currently no standard protocol to evaluate change in PIH following treatment. Based on these findings, we performed a pilot, exploratory, blinded, intraindividual‐controlled methodology study that consisted of a photographic assessment protocol with facial mapping. Materials and methods The study was based on a secondary analysis of a phase 4, community‐based trial of 544 acne patients who were treated with tretinoin gel microsphere 0.04% or 0.1%. Only patients with Fitzpatrick types III–V (skin of colour) were included in the study; subjects with Fitzpatrick skin type VI were excluded because the photographic assessment did not allow for proper evaluation. Results Despite the small number of subjects evaluated (n = 25), the results revealed consistent assessment of improvement in PIH between two independent graders (weighted κ = 0.84). Conclusion Further study with a larger population is recommended to validate the accuracy of this method.  相似文献   
59.
Background Bedbugs (Cimex lectularius) have been feeding on sleeping human beings since prehistory. In Europe, bed bugs were common and endemic until World War II when improved body and home hygiene, and widespread use of insecticides led to almost complete eradication. Current evidence indicates that bedbugs are making a comeback in Europe, USA, Canada and Australia. In our practice in Southern France, we observed several cases within a period of only 1 year. Objectives Based on this experience, we conducted an epidemiological study to evaluate the status of bedbugs in France. Methods During summer 2009, we mailed a short questionnaire to all hospital professors in the CEDEF (Collège des Enseignants de Dermatologie de France) asking four questions: number of suspected diagnosis of bedbugs in the year 2009, and number of certain positive diagnosis, difficulties in treatment, use of a pest control professional for treatment, and finally personal opinion on actual incidence of bedbugs, compared with past years. Results Of the 84 questionnaires sent, there were only 26 responses despite two reminders. The responses were predominantly southern France, probably as a result of intensive immigration and increased travel and trade. Difficulties encountered during diagnosis and treatment are also mentioned. Utilizing the services of entomological experts and pest control professionals is essential. Conclusions France has the same experience regarding the resurgence of bedbugs as several European countries, USA, Canada and Australia, especially the southern regions. This emerging health problem has to be known by dermatologists. A national programme has been launched in France to assess actual incidence and study C. lectularius‐ related diseases.  相似文献   
60.
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