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1.
We have isolated the delta-globin gene of the New-World spider monkey,
Ateles geoffroyi, and compared its nucleotide sequence with those of other
primate delta- and beta-globin genes. Among primate delta-globin genes, the
rate of nonsynonymous substitutions is much less than the rate of
synonymous substitutions. This suggests that primate delta- globin genes
may remain under evolutionary conservation, perhaps because hemoglobin A2
has an as yet unknown physiological importance.
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SUSAN G LANGRETH JONATHAN D. BERMAN G. PATRICK RIORDAN LINDA S. LEE 《The Journal of eukaryotic microbiology》1983,30(3):555-561
The mechanism of action of antileishmanial compounds is poorly understood. Ultrastructural changes in Leishmania tropica within human macrophages exposed in vitro to Pentostam, pentamidine, amphotericin B, WR 6026, ketoconazole, and Formycin B were examined in these experiments. In Pentostam-treated cultures, some organisms exhibited diminished definition of mitochondrial and other membranes, while other organisms had completely disintegrated. Pentostam-exposed macrophages demonstrated loss of membrane definition in the absence of further alterations; it is therefore hypothesized that impaired macrophage membrane function may contribute towards the effect of this drug against macrophage-contained organisms. Leishmania parasites in pentamidine-treated cultures initially demonstrated swollen kinetoplasts and fragmentation of the kinetoplast DNA core. The initial observed effect of the other four drugs on the parasites was cytoplasmic condensation. These ultrastructural studies suggest that all five non-antimonial drugs may have different mechanisms of action than antimony (Pentostam) against Leishmania. 相似文献
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WINSTON D. EDWARDS JULES J. BERMAN JERRY M. RICE MARK W. TOWNSEND 《Development, growth & differentiation》1979,21(6):519-525
The differentiation in organ culture of a rat nephroblastoma is compared with differentiation of normal rat metanephric tissue under the same conditions. The nephroblastoma arose in a 19 week old female Fischer F344 rat given a single intraperitoneal injection of 4.0 μmole methyl(methoxymethy1)nitrosamine (DMN-OMe)/g body weight at one day of age. The tumor consisted almost entirely of spindle cells although a few well-differentiated tubules were scattered throughout the tumor mass. No primitive tubules were seen, but focal aggregates of tumor cells suggestive of nascent epithelial differentiation were frequent. Fragments of the nephroblastoma were cultured on gelfoam sponge in Williams Medium E supplemented with hydrocortisone, insulin, and fetal bovine serum. Within one day extensive tubulogenesis was observed. High mitotic activity resulted in a steady increase in the size of cultured explants over a period of 6 days. By day six, differentiating tubules filled the explant tissue. Cultured fragments were nearly indistinguishable histologically from normal F344 rat fetal kidney explanted to organ culture on day 15 of gestation and grown in vitro for the same period. 相似文献
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Giselle?L?Ferrari Jefferson?LB?Marques Rajiv?A?Gandhi Simon?R?Heller Fábio?K?Schneider Solomon?Tesfaye Humberto?R?GambaEmail author 《Biomedical engineering online》2010,9(1):26
Background
Autonomic neuropathy is a common and serious complication of diabetes. Early detection is essential to enable appropriate interventional therapy and management. Dynamic pupillometry has been proposed as a simpler and more sensitive tool to detect subclinical autonomic dysfunction. The aim of this study was to investigate pupil responsiveness in diabetic subjects with and without cardiovascular autonomic neuropathy (CAN) using dynamic pupillometry in two sets of experiments. 相似文献8.
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一种新的肝细胞生成素(HPO)转录本及其生物学活性 总被引:3,自引:1,他引:2
利用 5′RACE技术从人胎肝组织中分离一种新形式的肝细胞生成素 (HPO 2 0 5 )cDNA ,其编码蛋白质氨基酸序列的N端较已报道的人肝细胞生成素HPO(hepatopoietin)多 80个氨基酸 ,推测其蛋白质分子量为 2 3kD。RT PCR检测HPOmRNA在多种肝癌细胞中表达 ,Western印迹可检测到 2 3kDHPO 2 0 5表达 ,表明此种形式HPO在自然状态下存在。将构建的HPO 2 0 5真核表达载体转染入COS 7细胞 ,其表达蛋白质能够刺激HepG2肝癌细胞DNA合成 ;将HPO 2 0 5、HPO和荷空表达载体分别转染入低水平表达HPO的Bel 740 2肝癌细胞株 ,发现HPO 2 0 5比HPO具有较强的激活MAPK磷酸化的活性。细胞周期分析稳定转染HPO 2 0 5 ,HPO细胞的增殖周期也支持这一结论。这些结果表明HPO 2 0 5具有刺激肝源性细胞增殖的活性 ,并提示HPO 2 0 5可能较HPO有更强的生物学活性 相似文献