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991.
BACKGROUND: Mixed hematopoietic chimerism is a reliable means of tolerance induction, but its utility has not been demonstrated in discordant xenogeneic combinations because of the difficulty in achieving lasting hematopoietic engraftment. Miniature swine are likely to be suitable organ donors for humans. To evaluate the ability of mixed chimerism to induce swine-specific tolerance in widely disparate xenogeneic recipients, this study aimed to achieve long-lasting chimerism in a pig to mouse combination. METHODS: Immunodeficient transgenic mice were developed by crossing transgenic founders carrying porcine interleukin-3, granulocyte macrophage-colony stimulating factor, and stem cell factor genes with severe combined immunodeficient mice or non-obese diabetic/severe combined immunodeficient mice. Swine bone marrow transplantation was performed in these mice, and porcine chimerism was followed for 20 weeks. RESULTS: Whereas swine cells became undetectable in all non-Tg littermates by 7 weeks, high levels of porcine hematopoietic chimerism, including the presence of porcine class II+ cells in the host thymus were maintained in Tg mice for >20 weeks. Colony-forming assays revealed the presence of large numbers of swine hematopoietic progenitor cells in the marrow of these mice at 20 weeks after bone marrow transplantation. CONCLUSIONS: These transgenic mice demonstrate for the first time that spontaneous migration of marrow donor antigen-presenting cells to an intact recipient thymus can occur and that porcine stem cells can persist in this highly disparate species combination. These data therefore support the feasibility of the eventual goal of tolerance induction by mixed chimerism in discordant xenogeneic combinations. 相似文献
992.
Morphologic changes in efferent ductules and epididymis in estrogen receptor-alpha knockout mice 总被引:3,自引:0,他引:3
Estrogen has been shown to have an important role in fluid reabsorption in efferent ductules of the testis. Our previous study of the estrogen receptor-alpha knockout mouse (ERKO) showed that the efferent ductules and rete testis were primary targets of estrogen receptor function. In the present study, a more comprehensive evaluation of the ERKO male reproductive tract was performed to determine the severity of effects in efferent ductules as well as the epididymis. The following observations were found in ERKO males: 1) blind-ending efferent ductules were more prevalent in ERKO than in wild type (WT) tissues; 2) glycogen-containing cells were observed at the rete testis-efferent ductule junction; 3) the tubular diameters of the efferent ductules and initial segment epididymides were dilated; 4) efferent ductules were dilated between 130 to 300% over wild type ductules; 5) efferent ductule epithelial height was reduced nearly 50%; 6) microvilli of nonciliated cells of efferent ductules were 64% shorter in length; 7) cilia were reduced in number; 8) initial segment epithelium was displaced into regions adjacent to the rete testis and in short segments of the common region of efferent ductule; 9) apical, narrow, and clear cells of the epididymis also were abnormal in some regions; 10) in the corpus and cauda regions, sperm granulomas were noted in one third of the ERKO males. In conclusion, the entire reproductive tract is affected in ERKO males. The cells showing the greatest effects were estrogen receptor-positive cells. It appears that in the ERKO mouse there are developmental anomalies that must be considered separately from adult dysfunctional changes in the male reproductive tract. 相似文献
993.
994.
目的 :研究细胞周期蛋白D1与E在非小细胞肺癌 (NSCLC)发生、发展中的作用及相互关系。方法 :免疫组化方法检测 87例NSCLC肿瘤组织中细胞周期蛋白D1、E的表达及PCNA估计增殖指数 (PI) ,并将上述结果与临床病理及预后资料进行对比分析。结果 :87例NSCLC中细胞周期蛋白D1、E阳性率分别为 4 4 .8% (39/87)、4 8.3% (42 /87) ,细胞周期蛋白D1阳性组的PI值显著高于阴性组 (P〈0 .0 5 ) ,细胞周期蛋白E阳性组PI值与阴性组无显著差异 (P〉0 .0 5 ) ;细胞周期蛋白D1阳性组肿瘤直径、淋巴结转移率和生存率均与阴性组有显著差异(P〈0 .0 1、〈0 .0 5、〈0 .0 1) ,细胞周期蛋白E阳性组淋巴结转移率、临床分期和生存率均与阴性组有显著差异 (P〈0 .0 5、〈0 .0 5、〈0 .0 1) ;细胞周期蛋白D1阳性组中细胞周期蛋白E的阳性率显著高于其阴性组 (P〈0 .0 5 ) ;细胞周期蛋白D1与细胞周期蛋白E双阳性组的PI值、肿瘤直径、淋巴结转移率显著高于非双阳性组 (P值均〈0 .0 5 ) ,生存率显著低于非双阳性组 (P〈0 .0 1)。结论 :细胞周期蛋白D1、细胞周期蛋白E均参与NSCLC的发生、发展 ,并影响其预后 ,但两者在其中所起作用不同 :细胞周期蛋白D1是调节NSCLC增殖的主要因素 ,细胞周期蛋白E主要与NSCLC进展有关 ;细胞周期蛋白D1可促 相似文献
995.
OBJECTIVES: To observe the role of the engineered growth plate (EGP) in the treatment of premature arrest of growth plate and to establish a novel treatment method for the premature arrest of the growth plate. METHODS: The engineered growth plates were cultured for the first time by using polylactic acid (PLA) as cell scaffold seeded with growth plate chondrocytes and they were implanted into the medial proximal defects of growth plates of New Zealand rabbit tibia. The degree of deformity of the tibia was evaluated by X-ray and the expression of collagen II mRNA of regenerating growth plate was detected by in situ hybridization technique. RESULTS: Little deformity appeared in the EGP group 8 weeks after operation. Some deformity was seen in the EGP group 16 weeks after operation, whereas it's degree was much less than that of the control group (P = 0.0001). The degree of the angular deformity of the EGP precultured with bFGF and TGF-beta group was less than that of the EGP group (P < 0.05). The cells in the regenerating growth plate arranged in column and were stained blue by in situ hybridization technique. CONCLUSION: The EGP can prevent the formation of bony bridge and restore the growth of the damaged growth plate. 相似文献
996.
糖皮质激素诱导性股骨头坏死模型的血管改变 总被引:18,自引:1,他引:17
目的 探讨在糖皮质激素诱导股骨头坏死过程中血管形态的改变与髓腔内脂肪填塞的关系。 方法 12~ 18个月龄的健康日本大耳白兔 5 2只 ,按 2 5mg·kg-1·d-1注射地塞米松建立股骨头坏死模型 ,通过血管铸型扫描电镜观察、墨汁灌注切片光镜观察及图像分析等方法观察用药中和停药后股骨头病理和血管形态的变化。 结果 用药 2周出现股骨头髓腔内脂肪填塞 ,窦状隙血管因脂肪细胞压迫变细 ,血管铸型、墨汁灌注切片显示了血管表面压迹。病变随用药时间的延长而加重 ,窦状隙血管逐渐失去其结构特征。图像分析示股骨头内血管面积进行性下降 ,8周约为对照组的1/ 4。停药 6周负重区髓腔内仍存在明显脂肪化 ,血管纤细、稀少。实验 4周 ,股骨头内出现典型骨坏死灶。随时间的延长 ,坏死灶增大、股骨头坏死程度加重。 结论 髓腔内脂肪填塞是导致糖皮质激素诱导性股骨头坏死中缺血损害的重要病理因素之一 ,尤其在股骨头坏死的早期起着非常重要的作用 相似文献
997.
998.
川红花产地环境及品质特性研究 总被引:1,自引:0,他引:1
川红花是传统的活血化瘀中药材,本文从川红花道地产区简阳的产地生态环境、产区的种植历史、与其它品种质量的比较等多方面研究了川红花的品质特性。结果表明,简阳具有悠久的川红花种植历史,良好的种植技术和品牌效应,产地生态环境因子(大气、土壤、农田灌溉、水质)符合中药材生产质量管理规范(GAP)要求;川红花品种的有效成份黄色素和红色素含量高,其吸收度分别为0.614和0.844,符合《中国药典》2000年版一部要求,并高于其它同生态条件种植的非地道性品种,其水溶性黄酮苷类的含量也高于其它品种;在不影响黄色素和黄酮苷类含量的条件下改进采收加工技术可大幅度提高红色素的含量,吸收度可达1.271,对红色素工业化提取极有利用价值;川红花药材的主要重金属和农药残留量均明显低于国家药材进出口绿色行业标准。实施川红花规范化栽培及按GAP要求建立生产基地后将进一步提高川红花的品质,增强川红花的国际市场竟争能力。 相似文献
999.
目的 建立地黄中地黄苷D的HPLC测定方法,提出地黄苷D的含量限度。方法HypersilC18分析柱(250mm×4.6mm,5μm),流动相为乙腈-水(4:96),流速为1mL/min,柱温为室温,检测波长为205nm。结果 地黄苷D回收率为100.6%,RSD为2.1%,8个产地的16份完整药材中地黄苷D的含量为0.137%~0.691%。结论 方法快速、简便、准确,可用于地黄质量控制,建议地黄苷D的含量应不低于0.15%。? 相似文献
1000.
哈尔滨市南岗区1992~2001年乳腺癌发病死亡趋势 总被引:3,自引:0,他引:3
[目的]分析1992年~2001年哈尔滨市南岗区女性乳腺癌发病和死亡水平及变化趋势,预测近期发病率和死亡率水平。[方法]资料来源于南岗区恶性肿瘤发病死亡登记报告系统,采用ICD-9进行死因分类,利用SPSS软件包分析,采用灰色系统GM(1,1)进行预测。[结果]10年间女性乳腺癌发病率和死亡率呈上升趋势,年平均发病率和死亡率分别为31.95/10万和7.91/10万。乳腺癌发病和死亡分别居女性恶性肿瘤发病和死亡的第二位和第三位,分别占恶性肿瘤发病和死亡的21.17%和7.90%。25岁~35岁乳腺癌发病率增加明显。预测2006年女性乳腺癌发病率和死亡率将分别达到54.98/10万和11.36/10万。[结论]女性乳腺癌发病率和死亡率呈逐渐缓慢升高趋势,预测女性乳腺癌发病率和死亡率分别将以每年3.7%和2.2%的速度递增。 相似文献