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61.
用~3H-TdR掺入法观察不同稀释度的正常人与重症肌无力患者胸腺提取液对健康成人外周血淋巴细胞增殖的影响。实验证实了正常儿童的胸腺功能下降(高浓度P<0.02,余浓度P>0.05),成人胸腺无功能(P>0.05);并且得出增生型重症肌无力胸腺提取液对PHA诱导的人外周血淋巴细胞增殖有促进和抑制双向作用。提示重症肌无力患者的胸腺免疫活性与正常人比较有差异。解释并肯定了手术切除胸腺治疗增生型重症肌无力的作用。 相似文献
62.
为了探讨蜂王宝对免疫功能的影响,用蜂王宝对受抑小鼠进行了淋巴细胞增殖,抗体形成细胞等免疫功能试验。在正常淋巴细胞增殖中,蜂王宝组与正常对照组比较差异非常显著(P<0.01),在PHA诱导的小鼠淋巴细胞增殖中,蜂王宝组与正常对照组比较和蜂王宝+强的松龙组与强的松龙组比较差异也非常显著(P<0.01).蜂王宝+强的松龙组与强的松龙组的脾重比较差异有显著性(P<0.05),结果显示,蜂王宝能显著提高受抑小鼠淋巴细胞增殖能力,而对体液免癌无明显作用。 相似文献
63.
64.
D. M. Samarin G. V. Seledtsova V. I. Seledtsov V. Ya. Taraban V. A. Kozlov 《Bulletin of experimental biology and medicine》1997,123(1):57-60
Immature erythroid cells suppress the proliferative response of preactivated B lymphocytes to lipopolysaccharide. The same
effect is observed when recombinant human interleukin-2 or culture medium conditioned by preactivated T or B cells is added
to cultured cells. Suppressive nucleate erythroid cells are resistant to leucine methyl ester.
Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 1, pp. 66–70, January, 1997 相似文献
65.
Vijay Tumuluri Graham A. Thomas Ian S. Fraser 《Journal of oral pathology & medicine》2004,33(4):204-208
BACKGROUND: We hypothesise that the density of proliferating cells at the invasive tumour front (ITF) has a positive relationship with prognostic and risk factors in human oral squamous cell carcinoma (SCC). METHODS: Tissues from 47 human oral SCC specimens were collected and stained with a monoclonal antibody directed against the Ki-67 antigen using a horseradish peroxidase based two-step immunostaining method. Counting was performed on two parallel sections at the ITF using an image analyser. The Ki-67 labelling index (LI) was determined by measuring the number of nuclei/mm(2) of epithelium. RESULTS: Our results show that the density of proliferating cells is related to clinical staging, with advanced stage of disease having a significantly higher Ki-67 LI compared with early stage of disease (2111 +/- 905 vs. 1908 +/- 913; P = 0.03). Importantly, this study shows that tumours that have metastasised have a significantly higher Ki-67 LI than tumours where distant metastasis was not detected (3257 +/- 650 vs. 1966 +/- 881; P < 0.0001). CONCLUSIONS: Cell proliferation, as measured by the Ki-67 LI at the ITF, has a positive relationship with clinical staging, tumour thickness, smoking status of the patient and alcohol consumption. Further, we suggest that a multicenter study with a large cohort of patients is indicated to fully elucidate whether cell proliferation at the ITF is directly related to patient survival. 相似文献
66.
Background: Solitary pigmented lesions of melanocytic origin are uncommon in the oral mucosa. These lesions include the oral and labial melanotic macule, oral melanocytic nevus, oral melanoacanthoma, oral melanoma and atypical melanocytic proliferation. The purpose of the study was twofold: to report a large series of solitary melanocytic lesions from one source, and to determine the relative frequency of these lesions. Methods: The study was based on a systematic search of the files of the Pacific Oral and Maxillofacial Pathology Laboratory, University of the Pacific, San Francisco for solitary pigmented melanocytic lesions (benign and malignant) accessed during the years 1984–2002. Results: Of the 89 430 biopsies accessed during the 19‐year period, 773 (0.83%) cases of solitary pigmented melanocytic lesions in the oral mucosa were identified. Oral and labial melanotic macules were the most common melanocytic lesions comprising 86.1% of the entire group and 0.7% of the total number of accessed biopsies. The vermilion border and gingiva were the most common sites (31.1% and 31.0% respectively). Oral melanocytic nevi comprised 11.8% of the entire melanocytic group and 0.1% of the total number of biopsies. The most common site was the palate (44%). Intramucosal nevi were the most common (64%), followed by compound nevi (16.5%) and common blue nevi (16.5%). Junctional nevi were uncommon (3.0%). Oral melanoacanthoma comprised only 0.9% of the entire melanocytic group and 0.008% of the total number of biopsies. Oral melanoma and atypical melanocytic proliferation were the least common lesions each comprising 0.6% of the entire melanocytic group and 0.006% of the total number of biopsies. The most common site for oral melanoma was the palate (60%). Conclusion: The palate was the most common location for both melanocytic nevi and oral melanoma. Thus, all melanocytic lesions in the palate should be viewed with caution and biopsy is recommended to rule out melanoma. Further studies are required to elucidate the entity of oral atypical melanocytic proliferation. 相似文献
67.
本文根据β_2-受体兴奋剂和茶碱类药物的作用机制,结合两类药物的基本结构和构效关系,运用新药设计中的拼合原理及生物电子等排原理,设计扦合成了两类共十六个尚未见于文献报导的化合物。经初步药理实验证明均具有抗哮喘作用,其中I_(5-8)活性较高,且对心脏副作用轻微,可望成为治疗哮喘的新药。 相似文献
68.
69.
The purpose of this study was to investigate the histogenesis of experimental tumors in the rat esophagus. Thirty rats received 0.0015% N-methyl-N-amylnitrosamine (MNAN) in the drinking water for 12 weeks. Another 30 rats received tap water. All rats then received tap water until sacrifice. Rats from each group were sacrificed immediately after MNAN administration, four weeks after, and eight weeks after. One hour before sacrifice, [3H]TdR was injected by tail vein to label proliferating cells. The entire esophagus and stomach were removed and processed for light and electron microscopy and autoradiography. The overall frequency of esophageal tumors after MNAN was 83% and did not differ significantly among the three experimental groups. Tumors were primarily papillomas and squamous cell carcinomas and occurred with equal frequency in the upper, middle, and lower thirds of the esophagus. No tumors were found in the squamous-lined forestomach. Electron microscopy revealed abundant tonofilaments, free ribosomes, and mitochondria accompanied by vacuoles. By autoradiography, esophageal epithelial proliferation was markedly stimulated in nontumorous mucosa from all three experimental groups. We conclude that MNAN ingestion for 12 weeks reliably produces papillomas and squamous cell carcinomas throughout the rat esophagus, but not in the squamouslined forestomach, and that MNAN stimulated marked epithelial proliferation which is accompanied by thickening of the epithelium in nontumorus esophageal mucosa. 相似文献
70.
目的 探讨胃肠富集kruppel因子 (GKLF)在宫颈鳞癌组织及正常宫颈组织中的表达及意义。方法 应用半定量的逆转录聚合酶链式反应 (RT -PCR)方法检测 32例宫颈鳞癌组织 (研究组 )中GKLFmRNA的表达强度 ,以 10例正常宫颈组织作为对照 (对照组 )。结果 GKLFmRNA在正常宫颈组织中的表达强度为 0 .76± 0 .15 ,而在宫颈鳞癌中的相对表达强度为 0 .4 2± 0 .19,与正常宫颈组织相比较 ,宫颈鳞癌组织中GKLFmRNA的表达丰度较低 (P <0 .0 5 )。而且临床分期愈晚 ,GKLFmRNA的表达强度愈低 ,差异有显著性 (P <0 .0 5 )。随着病理分级增高 ,GKLFmRNA的表达强度逐渐降低 ,差异有显著性 (P <0 .0 5 )。结论 宫颈鳞癌组织中GKLF表达下调 ,而且GKLFmRNA的表达与宫颈癌的临床分期和病理分级呈负相关 ,提示GKLF可能参与了宫颈癌的发生或进展过程 相似文献