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11.
Paul P. W. van Buul Iris M. Zandman Mira Grigorova Jan J. W. A. Boei Adayapalam T. Natarajan 《Chromosome research》1995,3(7):427-432
The efficiency of two methods of detection of translocations induced in mouse stem cell spermatogonia by X-ray doses of 2, 5 and 7 Gy was compared: classical multivalent analysis at diakinesis-metaphase I of meiosis and observation via fluorescencein situ hybridization analysis of mitotic or meiotic stages. Specific DNA libraries for chromosomes 1, 11 and 13 were used. The results obtained indicate that (a) chromosomes 1, 11 and 13 are more involved in multivalent formation than expected on the basis of DNA content and (b) if the mitotic FISH analysis data are corrected for the observed over-representation, the frequencies of induced translocations are similar to those recorded in the classical multivalent studies, suggesting equal scoring efficiencies in both systems. 相似文献
12.
烹调油烟致大小鼠肺癌的实验研究 总被引:1,自引:0,他引:1
[目的]了解烹调油烟(cooking oil fumes,COF)的动物致癌性。[方法]采用动式染毒法给Balb/c小鼠(雌雄各半)吸入COF浓度为9.09、20.65、38.85mg/m^3,染毒1次/1~2d,30min/次,共150次,计8个月;SD大鼠(雌雄各半)吸入COF浓度为6、88、15.06、35.33mg/m^3,染毒1次/2d,30min/次,共191次,计12.5个月。分别制备COF慢性中毒动物模型;两实验均设空白对照组,吸入与实验组相同温度的清洁空气。[结果]COF诱发Balb/c小鼠实验组肺癌总发生率为18、95%(29/153),低、中、高浓度组肺癌发生率分别为15.09%、20、00%和22.00%,与对照组差异均有显著性。但低、中、高三组间差异无显著性(P〉0.05);COF诱发SD大鼠肺癌总发生率为9、10%(9/99),低、中、高浓度组肺癌发生率分别为6.45%、8.57%、12.12%,高浓度组肺癌发生率高于对照组(P〈0.05)。各性别组间肺癌发生率的差别无显著性(P〉0.05)。[结论]COF可以诱导Balb/c小鼠和SD大鼠肺癌,诱发的肺癌主要为肺腺癌(小鼠28/29,大鼠7/9),余为小细胞肺癌。 相似文献
13.
14.
J. Duteil FA Rambert AM Pointeau P. Mangiameli and E. Assous 《Fundamental & clinical pharmacology》1991,5(8):695-708
The potential antidepressant effect of flerobuterol (dl-(fluoro-2 phenyl)-1 t-butylamino-2 ethanol), a new drug related to beta-adrenoceptor agonists, was evaluated and compared with imipramine and salbutamol using classical psychopharmacological tests in mice. Like imipramine and salbutamol, flerobuterol (0.5-32 mg kg-1, ip) fully prevented apomorphine (16 mg kg-1, sc)- and partly reversed reserpine- and oxotremorine-induced hypothermia. At higher doses (16-32 mg kg-1), flerobuterol enhanced the toxic effects of yohimbine. Unlike imipramine, flerobuterol and salbutamol did not reduce immobility duration in the behavioural despair test. Salbutamol and flerobuterol decreased locomotor activity. Flerobuterol did not induce mydriasis, did not prevent oxotremorine-induced tremors or salivary and lacrimal gland secretion and did not reduce reserpine-induced palpebral ptosis. Propranolol (8 mg kg-1, ip) but not alpha-methyl-paratyrosine (75 mg kg-1, ip) prevented the flerobuterol-induced antagonism of apomorphine-induced hypothermia. Our results suggest that flerobuterol demonstrates potential antidepressant activity, which could be related to beta-adrenoceptor activation in mice. 相似文献
15.
Summary This study was undertaken to elucidate, using the Golgi method, the neuropathological change in the brain of the macular mutant mouse, whose hemizygote (Ml/y) is considered to be a model of Menkes kinky hair disease (MKHD). The hemizygote mice gradually lost weight after 10 days of age and died with emaciation and seizure around day 15. The normal littermate (+/y) was well developed. In the cerebrum, the arborization of pyramidal neurons in the layer V of the Ml/y was the same as that in the +/y on day 10. However, development of arborization in the Ml/y was delayed in comparison with that in the +/y on days 12 and 14. Purkinje cells with several somal sprouts were observed in the cerebellum in both the Ml/y and +/y on day 7. The somal sprouts in the +/y had regressed gradually by day 12, while they were still in the anterior and middle lobes of the Ml/y on day 14. Additionally, the trunks of Ml/y stem dendrites became thicker and a cactus formation was recognized on the branching portion of the dendrites on day 14. Arborization of these abnormal Purkinje cells was distinctly poor compared with that in the +/y. These results suggest that the growth of the neurons is delayed in the Ml/y and simultaneously their cytoskeletal developments are disturbed, especially in the Purkinje cells. There is a close similarity in many respects to the neuropathological change in MKHD. 相似文献
16.
目的 研究甘肃棘豆生物碱部位对KM小鼠肝癌H22细胞抑制作用及其对KM小鼠免疫功能的影响。 方法 采用鼠源性肝癌细胞H22移植瘤法,将60只KM小鼠随机分为5组,其中高、中、低剂量组分别给予甘肃棘豆生物碱部位32、16、8 mg/kg体重灌胃,阴性对照组给予生理盐水(NS)20 mL/kg灌胃,5- 氟脲嘧啶(5-FU)组给予5-FU 15 mg/kg体重腹腔注射,每天1次,连续给药10天。检测平均瘤重和抑瘤率,计算脾指数、胸腺指数,MTT法测脾细胞增殖率。 结果 甘肃棘豆生物碱部位高、中、低剂量组对肝癌细胞H22实体移植瘤的抑制率分别为43%、29%、23%;各剂量组小鼠的脾指数和胸腺指数均明显高于阴性对照组,中、高剂量组明显高于5-FU 组(P<0.05);各剂量组在24、48、72 h的脾细胞增殖率也明显高于阴性对照组及5-FU 组(P<0.01)。 结论 甘肃棘豆生物碱部位对KM小鼠肝癌H22移植瘤有抑制作用,并能增强KM小鼠免疫功能。 相似文献
17.
Quantification of Basal and Stimulated ROS Levels as Predictors of Islet Potency and Function 总被引:2,自引:0,他引:2
B. Armann M. S. Hanson E. Hatch A. Steffen L. A. Fernandez 《American journal of transplantation》2007,7(1):38-47
We have developed a luminol-based assay using intact islets, which allows for quantification of reactive oxygen species (ROS). In addition, an index capable of characterizing metabolic and mitochondrial integrity prior to transplantation was created based on the capacity of islets to respond to high glucose and rotenone (mitochondrial respiratory chain complex I inhibitor) by production of ROS. To validate this assay, lipid peroxidation and antioxidative defense capacity were evaluated by detection of malondialdehyde (MDA) levels and glutathione peroxidase activity (GPx), respectively. Also, flow cytometric analyses of ROS (dihydroethidine), apoptosis (Annexin V, active caspases), necrosis (Topro3), and mitochondrial membrane potential (JC-1) were done in parallel to correlate with changes in luminol-measured ROS. ATP/ADP ratios were quantified by HPLC and the predictive value of ROS measurement on islet functional potency was correlated with capacity to reverse diabetes in a streptozotocin-induced diabetic NOD.scid mouse model as well as in human transplant recipients. Our data demonstrate that levels of ROS in islets correlate with the percentage of apoptotic cells and their functional potency in vivo. The ROS indices following glucose and rotenone exposure are indicative of metabolic potency and mitochondrial integrity and can be used as surrogate markers to evaluate the quality of islets prior to transplantation. 相似文献
18.
Histopathological characterisation of effects of the mouse Pax6 missense mutation on eye development
Thaya Ramaesh Steven E. Williams Catriona Paul Kanna Ramaesh John D. West 《Experimental eye research》2009,89(2):263-273
Mutations in PAX6/Pax6 lead to a variety of ocular anomalies in humans and mice. The aim of the study was to characterise the ocular abnormalities caused by the missense Pax6Leca4 mutation and compare them to published observations on Pax6 alleles that are functionally equivalent to Pax6− null alleles (such as Pax6Sey and Pax6Sey-Neu) and human inherited eye diseases. Ocular features of homozygous Pax6Leca4/Leca4 and heterozygous Pax6Leca4/+ embryos at E12.5-E18.5, heterozygous Pax6Leca4/+ young mice at P18 and heterozygous Pax6Leca4/+ adults at 12 weeks were analysed histologically with their wild-type Pax6+/+ littermates. Homozygous Pax6Leca4/Leca4 fetuses died perinatally with no eyes although an optic cup rudiment with pigmented cells developed. Pax6Leca4/+ mice were microphthalmic and a range of other severe ocular phenotypes affected both the anterior and the posterior segments. In contrast to Pax6+/−, the Pax6Leca4/+ eyes had no goblet cells in the corneal epithelium, the iris was not hypoplastic and there was no lens-corneal epithelial plug. However, microphthalmia was more severe, corneal vascularisation occurred earlier (during fetal stages), pigmented cells were present in the vitreous and corneal stroma and the ciliary body was malformed or abnormal. These results show that, although Pax6Leca4/+ lacked some eye abnormalities commonly seen in Pax6Sey/+ and Pax6Sey-Neu/+ eyes, in most respects their eyes were more severely affected. These differences probably reflect both differences between the Pax6Leca4 and the Pax6Sey-Neu mutations and differences in modifier gene expression in different genetic backgrounds. The presence of pigmented cells in the cornea is a novel observation. Some Pax6Leca4/+ ocular abnormalities were similar to those present in human Peters' anomaly and persistent hyperplastic primary vitreous (PHPV) so Pax6Leca4/+ mice provide a useful model for some inherited eye diseases. 相似文献
19.
目的 观察经祛瘀解毒颗粒治疗后子宫内膜异位症(endometriosis,EM)患者卵泡液对小鼠胚胎发育的影响。 方法 在常规培养液中分别加入治疗组EM患者卵泡液(祛瘀解毒颗粒)、对照组EM患者卵泡液及空白组(因输卵管因素行体外受精-胚胎移植)患者卵泡液,20只小鼠超排卵共收集189枚2 细胞鼠胚分别放入各组培养液进行培养,其中治疗组培养液70枚,对照组培养液60枚,空白组培养液59枚,观察和检测2 细胞鼠胚在体外发育至8细胞期、桑葚胚期和囊胚期的比率,及早期鼠胚优质胚胎数目和优质胚胎率。 结果 治疗组培养液有53枚鼠胚(75.71%,53/70)发育到8细胞期,48枚(68.57%,48/70)发育到桑葚胚期,45枚(64.28%,45/70)发育到囊胚期,与对照组培养液(56.67%,34/60、48.33%,29/60、35.00%,21/60)比较差异有统计学意义(P<0.05)。治疗组有61枚优质胚胎(87.14%),对照组为44枚(73.33%),两组比较差异有统计学意义(P<0.05)。 结论 EM患者卵泡液对早期鼠胚存在毒性作用,经祛瘀解毒颗粒治疗后EM患者卵泡液可提高早期鼠胚培养质量。 相似文献
20.
放线菌素23-21属放线菌素类抗癌抗生素,由浅黄色链霉菌产生,该菌从中国福州土壤样品中分离得到。采用裸小鼠人鼻咽癌细胞系(CNE-2Z)和人胃癌细胞系(MGc-803)两种移植模型观察了放线菌素23-21的作用。放线菌素23—21 50μg/kg,对CNE-27移植瘤和MGc803移植瘤的抑制率分别为58.4%(P<0.05)和68.7%(P<0.05)。肿瘤生长曲线显示,治疗组肿瘤生长缓慢。电镜检查,治疗组瘤细胞可见核仁分离和微球体形成。提示放线菌素23-21可能有抑制核仁rRNA合成的作用。在有效剂量下,未见重要脏器病理改变。 相似文献