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61.
Aneuploidy induction by water extract from Tripterygium hypoglaucum (Level) Hutch in mouse bone marrow cells 总被引:2,自引:1,他引:2
Hie aneuploidy-inducing activity of a Chinese medicinal herb,Tripterygium hypoglaucum (level) Hutch (THH), was investigatedby means of three cytogenetic end-points, i.e. C-mitotic (CM)effects, micronuclei (MN) and parallel chromosome structuralaberration (CA) analyses in vivo. The CA analysis was expectedto reflect the origins of MN induced by clastogens or aneugens.The experiments were performed on mouse bone marrow cells. Theanimals were treated with the crude water extracts of THH (singlei.p. injection) in the dose range 120686 mg/kg. Colchicine(COL) was taken as a positive control for its known aneuploidy-inducingeffects. THH showed similar genotoxic effects to COL in CM,MN and CA analyses: positive CM effects were observed accompaniedwith increases of mitotic index and frequencies of CM cellsas well as decreased frequencies of anaphase in all of the THH-treatedgroups. The compound showed a positive MN response in bone marrowpolychromatic erythrocytes but was negative in CA analyses.No sex differences were found in any treated group. The preliminaryresults suggested that THH is an aneuploidy inducer in mousebone marrow cells under the present experimental conditions. 相似文献
62.
M Avellanet RM Mirapeix D Escudero C Riera JM Domenech-Mateu 《Surgical and radiologic anatomy : SRA》1996,18(4):271-273
Summary We present a case with a characteristic magnetic resonance image (MRI) of bilateral open-lipped schizencephaly and atypical clinical presentation. The patient is still alive and in good health in her forties, she has never presented seizures, and although the motor dysfunction is well correlated with cerebral lobe involvement, neurobehavioral dysfunction is not proportional to the MR image of the cerebral malformation.
Un cas inhabituel de schizencéphalie bilatérale
Résumé Nous présentons un cas de schizencéphalie bilatérale ouverte caractérisé par une présentation clinique atypique et une imagerie par résonance magnétique nucléaire caractéristique. La patiente est encore vivante, en bonne santé, à plus de 40 ans, elle n'a jamais présenté de crise comitiale et, bien que les troubles moteurs soient bien corrélés aux altérations cérébrales, les troubles neuro-comportementaux ne sont pas proportionnels aux images IRM de cette malformation cérébrale.相似文献
63.
Kermit Zhang Eleina Cox Samuel Strom Zhuo Luan Xu Alexis Disilvestro Kelly Usrey 《American journal of medical genetics. Part A》2020,182(9):2124-2128
Baraitser‐Winter cerebrofrontofacial syndrome (BWCFF) is a rare autosomal dominant developmental disorder associated with missense mutations in the genes ACTB or ACTG1. The classic presentation of BWCFF is discerned by the combination of unique craniofacial characteristics including ocular coloboma, intellectual disability, and hypertelorism. Congenital contractures and organ malformations are often present, including structural defects in the brain, heart, renal, and musculoskeletal system. However, there is limited documentation regarding its prenatal presentation that may encourage healthcare providers to be aware of this disorder when presented throughout pregnancy. Herein we describe a case of a pregnancy with large cystic hygroma and omphalocele. Whole exome sequencing (WES) was performed and a de novo, heterozygous, likely pathogenic mutation in ACTB was detected, c.1004G>A (p.Arg335His), conferring a diagnosis of BWCFF. 相似文献
64.
为探讨烧伤对大鼠免疫功能的影响及不同免疫调节剂对它的作用,本研究利用烫伤大鼠实验模型,采用溶血分光光度法和微量细胞病变抑制法,在整体条件下分别测定了各组烫伤大鼠伤后第5、10天时脾细胞产生TFN-γ和抗SRTBC抗体的能力。 相似文献
65.
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67.
肾阳虚证患者红细胞LPO、SOD和ATP酶活性的变化 总被引:6,自引:0,他引:6
目的 :探讨肾阳虚证患者红细胞LPO、SOD和ATP酶活性的特点及其意义。方法 :观察 19例肾阳虚证患者和 2 1例正常人红细胞LPO、SOD和红细胞膜Na+ K+ ATP酶、Mg2 + ATP酶、Ca2 + ATP酶、Ca2 + Mg2 + ATP酶活性的变化。结果 :与对照组比较 ,肾阳虚证患者红细胞LPO含量升高 (P <0 .0 1) ,红细胞SOD活性降低 (P <0 .0 1) ;红细胞膜Na+ K+ ATP酶活性显著升高 (P <0 .0 1) ,而Mg2 + ATP酶活性变化无显著性差异 ,Ca2 + ATP酶活性升高 (P <0 .0 1) ,Ca2 + Mg2 + ATP酶活性也显著升高 (P <0 .0 1)。结论 :肾阳虚证患者红细胞内脂质过氧化反应增强 ,而抗氧化能力降低 ,红细胞膜Na+ K+ ATP酶、Ca2 + ATP酶和Ca2 + Mg2 + ATP酶活性升高 ;本研究为理解肾阳虚证的病理生理基础提供了初步实验依据 相似文献
68.
p21WAF1/CIPI基因导入对p53突变人肺癌细胞系生长特性的影响 总被引:2,自引:0,他引:2
目的 探讨含突变p53基因癌细胞系p21基因的抗肿瘤作用。方法 构建人p21表达重组子,导入p53基因突变的人肺癌PG细胞每当增产同表达p21的细胞系;然后观察其形态太生长特性的改变;CDK4,PCNA水平;对基因毒性物的反应性。结果 在含p53基因突变的PG细胞内导入的性p21基因,其高表达p21约是PG细胞的6倍,转谬为薄等异型性降低;生长速度下降(50%),叠落生长不明显;在0.5%血甭条件 相似文献
69.
70.
Yin C Ying L Zhang PC Zhuo RX Kang ET Leong KW Mao HQ 《Journal of biomedical materials research. Part A》2003,67(4):1093-1104
Galactosylated surface is an attractive substrate for hepatocyte culture because of the specific interaction between the galactose ligand and the asialoglycoprotein receptor on hepatocytes. In this study, we described a scheme to achieve high density of immobilized galactose ligands on polyethylene terephthalate (PET) surface by first surface-grafting polyacrylic acid on plasma-pretreated PET film under UV irradiation, followed by conjugation of a galactose derivative (1-O-(6'-aminohexyl)-D-galactopyranoside) to the grafted polyacrylic acid chains. A high galactose density of 513 nmol/cm(2) on the PET surface was used in this study to investigate the behavior of cultured hepatocyte. This engineered substrate showed high affinity to fluorescein isothiocyanate-lectin binding. Primary rat hepatocytes, when seeded at a density of 2 x 10(5) cells/cm(2), attached to the galactosylated PET substrate at a similar efficiency compared with collagen-coated substrate. The hepatocytes spontaneously formed aggregates 1 day after cell seeding and showed better maintenance of albumin secretion and urea synthesis functions than those cultured on collagen-coated surface. 相似文献