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91.
目的:探讨利用体外碎石机低能量冲击波促进皮瓣成活的可行性及探索理想的实验条件。方法:应用X线定位系统的KDE-2001A型体外冲击波碎石机以0.18mJ/mm2能量冲击波治疗对20只大鼠背部皮瓣模型分为单纯皮瓣组和冲击波治疗组,进行同体成活率对比观察结果:冲击波治疗组坏死面积明显小于单纯皮瓣对照组;冲击波治疗组毛细血管分布明显密集于单纯皮瓣组。结论:0.18mJ/mm2能量冲击波亦可提高皮瓣成活率,以X线C型臂为定位系统的国内碎石机可满足实验要求。 相似文献
92.
BackgroundThe effects and mechanisms of preweaning Manganese (Mn) exposure on cognitive dysfunction remain unclear.ObjectiveThis study evaluated the effects of preweaning Mn exposure on spatial learning and memory as well as the protein expression of CaMKIIα and p-CaMKIIα.MethodsWe treated neonate rats with Mn2+ doses of 0 (control group), 10, 20 and 30 mg of Mn2+ per kg body weight (Mn-exposed groups) over postnatal day (PND) 1–21 by intraperitoneal injection. The ability of spatial learning and memory was tested on PND 22 using the Morris water maze (MWM), while the protein expressions of CaMKIIα and p-CaMKIIα in the hippocampus were evaluated by Western blotting. The levels of Mn in the blood and hippocampus were measured by inductively coupled plasma-mass spectrometry (ICP-MS).ResultsThe rats in Mn-exposed groups showed a significant delay in spatial learning ability on the third day of the MWM without dose-dependent differences, but there was no effect on the spatial memory ability. p-CaMKIIα, but not CaMKIIα protein expression significantly reduced in the Mn-exposed group.ConclusionThese findings suggested that the inhibition of p-CaMKIIα could be one of the mechanisms involved in the occurrence of Mn-induced cognitive impairments. 相似文献
93.
Comparison of electroretinographic responses between two different age groups of adult Dark Agouti rats 下载免费PDF全文
AIM: To describe and compare the differences in electroretinographic responses between two different age groups of adult Dark Agouti (DA) rats and to better understand the effect of age on retinal histology and function.METHODS: The electroretinographic responses of two different age groups of adult DA rats were compared. Animals were divided into younger adult DA rats 10-12wk (n=8) and older adult DA rats 17-19wk (n=8). Full field electroretinography (ERG) was recorded simultaneously from both eyes after dark adaption and light adaption and parameters including the positive scotopic threshold response (pSTR), negative scotopic threshold response (nSTR), scotopic a-wave, b-wave, photopic a-wave, b-wave and photopic negative response (PhNR) were compared between groups.RESULTS: The older adult rats displayed lower stimulation thresholds of the STRs (pSTR and nSTR) and higher amplitudes of pSTR, scotopic a-wave and b-wave, photopic b-wave and PhNR amplitudes, with shorter implicit times. Photopic a-wave amplitudes were however higher in the younger adult rats.CONCLUSION:In summary, for the rod system, photoreceptor, bipolar cell and RGC activity was enhanced in the older adult rats. For the cone system, RGC and bipolar cell activity was enhanced, while photoreceptor activity was depressed in the older adult rats. Such age-related selective modification of retinal cell function needs to be considered when conducting ophthalmic research in adult rats. 相似文献
94.
目的:观察反式白藜芦醇( TR)对β-淀粉样肽(Aβ25-35)致痴呆大鼠海马旁回的保护作用。方法先将SD大鼠分为3,20月龄2大组,然后再分为假手术组、模型组、低与高剂量实验组。用Aβ25-35制痴呆模型后,实验组灌胃给TR 10,40 mg? kg-1? d-1,假手术组、模型组均给予0.9%NaCl(1 mL/100 g),连续10 d。用实时定量PCR法检测8组大鼠海马及皮质半胱氨酸蛋白酶-3(caspase-3)、DNA聚合酶γ的表达。结果模型组与假手术组的caspase-3、DNA聚合酶γ表达水平比较差异有统计学意义( P<0.01),说明造模成功。 TR对caspase-3、DNA聚合酶γ表达水平的下调非常显著( P<0.01)。模型组3月龄较20月龄大鼠的caspase-3表达量明显增高( P<0.05)。实验组3月龄与20月龄大鼠caspase-3表达量差别有统计学意义( P<0.05)。结论 TR对损伤的大鼠海马周围皮层神经元有保护作用。 相似文献
95.
纤维蛋白封闭剂对SD大鼠连续腹腔注射给药14天的毒性研究 总被引:1,自引:0,他引:1
目的 评价SD大鼠连续腹腔注射纤维蛋白封闭剂的安全性。方法 SD大鼠雌雄分别按体质量随机分4组,即空白对照组、纤维蛋白封闭剂低剂量组、中剂量组和高剂量组,每组20只,雌雄各半。3个给药组的给药剂量分别为85.5、171.0和342.0mg/kg,每天腹腔注射给药,连续14d,恢复期28d,进行一般症状、血液学、血液生化和病理组织学等指标检测。结果 与空白对照组相比,纤维蛋白封闭剂中、高剂量组大鼠第14天的白细胞计数显著升高,纤维蛋白原显著降低,中、高剂量组大鼠脾脏的脏器重量有增加趋势。组织病理学检查发现部分高剂量动物腹腔出现残留药物引起的纤维肉芽组织包裹。上述变化指标在恢复期结束时基本可恢复。结论大鼠腹腔注射纤维蛋白封闭剂85.5~342.0mg/kg,安全剂量为85.5mg/kg,毒性剂量为171.0mg/kg。毒性靶系统或靶部位为血液系统、免疫系统和给药局部,毒性作用可逆。 相似文献
96.
Dimethylarsinic acid (DMAV) changed the expressions of proliferative related factors and secretion of inflammatory cytokines in rat bladder 下载免费PDF全文
Zhang Lin Liu Shengnan Wang Fei Song Yingli Sun Qingshan Sheng Wei Xi. Shuhua Sun Guifan 《Journal of applied toxicology : JAT》2015,35(2):133-141
Dimethylarsinic acid (DMAV), the major urinary metabolite of inorganic arsenic, is a urinary bladder carcinogen and bladder tumor promoter in adult rats. Increased urothelial cellular proliferation has been considered as an earlier phenotype in DMAV‐induced bladder carcinogenesis. The present study examined the ultrastructural changes of bladder epithelial cells and expressions of proliferation factors, as well as the secretion of inflammatory cytokines in rats exposed to DMAV for 10 weeks by transmission electron microscopy (TEM), qRT‐PCR, immunohistochemical staining and ELISA methods. The results showed that DMAV administered in the drinking water produced urothelial cytotoxicity and ultrastructural changes in rats. PCNA, cyclin D1 and COX‐2 mRNA expressions and immunoreactivities were elevated in bladder urothelium. In addition, 200 ppm DMAV treatment increased the transforming growth factor‐beta 1 (TGF‐β1) secretion and decreased tumor necrosis factor‐alpha (TNF)‐α level in the urine of rats. These data suggest that chronic inflammation, bladder epithelium lesions and proliferation might be the basic process of the chronic toxicity effects in DMAV‐treated rats. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
97.
Absorption,distribution, metabolism and excretion of novel phosphodiesterase type 4 inhibitor ASP3258 in rats 下载免费PDF全文
Yoshiaki Ohtsu Takuya Sonoda Yoko Susaki Toshifumi Tohda Yasuhisa Fukunaga Takafumi Iwatsubo Kiyoshi Noguchi 《Biopharmaceutics & drug disposition》2015,36(1):34-48
The potent and selective phosphodiesterase 4 inhibitor ASP3258 is a novel therapeutic agent for asthma and chronic obstructive pulmonary disease (COPD). After a single oral administration to rats, ASP3258 is rapidly absorbed with a bioavailability of 106%. In situ absorption data indicated that ASP3258 is mainly absorbed in the small intestine. Tissue distribution data after oral administration of 14C‐ASP3258 showed rapid and extensive distribution to various tissues. Excluding the gastrointestinal tract, the tissues with the highest concentrations were liver, heart and plasma. Liquid chromatography‐nuclear magnetic resonance spectroscopy data revealed that O‐glucuronidation of the carboxylic acid moiety of ASP3258 (formation of an acyl glucuronide) plays a key role in metabolism. No indication was found that the acyl glucuronide reacted with proteins in plasma or tissues. When 14C‐ASP3258 was orally administered to intact rats, urinary and fecal excretion accounted for 1.3% and 100.6% of the administered radioactivity, respectively. After a single oral administration of 14C‐ASP3258 to bile‐cannulated rats, urinary and biliary excretion accounted for 0.7% and 93.8% of the administered radioactivity, respectively. These findings suggest that fecal excretion via bile plays an important role in the elimination of ASP3258‐derived radioactivity. In vitro metabolic profiles were relatively similar among the species examined, suggesting that our findings in rats may help us to understand pharmacokinetics, efficacy and safety profiles in humans and other species. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
98.
Oral cadmium exposure during rat pregnancy: assessment of transplacental micronutrient transport and steroidogenesis at term 下载免费PDF全文
Anja Mikolić Martina Piasek Antonija Sulimanec Grgec Veda M. Varnai Sandra Stasenko Saša Kralik Oguić 《Journal of applied toxicology : JAT》2015,35(5):508-519
Diet is the main source of cadmium (Cd) exposure. Gastrointestinal absorption increases during pregnancy. Cadmium accumulated in the placenta may interfere with nutrient transport to the foetus. Data on the potential of Cd to act as a steroid disruptor of pregnancy are limited. We evaluated the effects of oral Cd exposure during pregnancy on placental function in micronutrient transfer to the foetus and steroidogenesis in Wistar rats (regular 4‐day cyclers) that mated with unexposed males. Pregnant rats were randomly assigned to a Cd group exposed orally to 50 mg Cd l–1 (CdCl2xH2O dissolved in demineralized water), ≈7.5 mg Cd kg–1 a day, during 20 days of gestation and control (supplied with demineralized water). Non‐pregnant rats were treated under the same experimental conditions. On day 20, all of the rats were killed and samples were taken for element analyses (by electrothermal atomic absorption spectrometry). Progesterone and testosterone were measured in serum and placenta‐derived samples (by immunoenzymometric assay and/or enzyme‐linked immunosorbent assay). In the exposed rats, Cd increased in blood and organs, more in pregnant rats, and in placenta and foetus whereas zinc increased in liver. Iron decreased in maternal organs and in foetus, whereas zinc decreased in maternal kidney and placenta. Liver copper was lower and kidney copper higher in all pregnant vs. non‐pregnant rats. Steroids in serum and placenta did not change. In conclusion, oral Cd exposure during rat pregnancy does not affect progesterone and testosterone at term. Transplacental iron and zinc handover are disrupted, which may put at risk the maintenance of foetal nutrition and viability. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
99.
目的:研究新型蒽环类衍生物HYY-014在大鼠体内的药代动力学和组织分布特征,为临床研究提供实验依据。方法大鼠单次尾静脉注射1.5 mg/kg的HYY-014后,采用LC-MS/MS法测定各时间点血浆和组织中HYY-014及其代谢物HYY-M3的浓度,药代动力学参数经DAS 3.0统计软件计算获得。结果采用统计矩方法处理药物浓度时间数据, HYY-014药代动力学参数 Cmax、T1/2、Vd、CL、AUC0-t、MRT0-t分别为(1628.6±618.6)μg/L、(24.4±3.6) h、(23.4±5.2) L/kg、(0.66±0.08) L/kg/h、(2219.5±276.9)μg/L ·h、(15.1±2.4) h;HYY-M3药代动力学参数Cmax、AUC0-t分别为(2.2±0.6)μg/L、(103.1±13.7)μg/L·h。静脉注射该药后,很快向机体的各组织广泛分布,且具有明显的靶向性,主要分布在脾、肾、肺、心脏、肝等组织,脑组织中浓度极低。结论静脉注射HYY-014组织分布广泛,具有明显的靶向性,肺、肝组织中的药物浓度均较高,不能通过血脑屏障。 相似文献
100.
Fluorescent Visualisation of Oxytocin in the Hypothalamo‐neurohypophysial/‐spinal Pathways After Chronic Inflammation in Oxytocin‐Monomeric Red Fluorescent Protein 1 Transgenic Rats 下载免费PDF全文
T. Matsuura M. Kawasaki H. Hashimoto T. Ishikura M. Yoshimura J.‐I. Ohkubo T. Maruyama Y. Motojima K. Sabanai T. Mori H. Ohnishi A. Sakai Y. Ueta 《Journal of neuroendocrinology》2015,27(7):636-646
Oxytocin (OXT) is a well‐known neurohypophysial hormone that is synthesised in the paraventricular (PVN) and supraoptic nuclei (SON) of the hypothalamus. The projection of magnocellular neurosecretory cells, which synthesise OXT and arginine vasopressin in the PVN and SON, to the posterior pituitary plays an essential role in mammalian labour and lactation through its peripheral action. However, previous studies have shown that parvocellular OXTergic cells in the PVN, which project to the medulla and spinal cord, are involved in various physiological functions (e.g. sensory modulation and autonomic). In the present study, we examined OXT expression in the PVN, SON and spinal cord after chronic inflammation from adjuvant arthritis (AA). We used transgenic rats that express OXT and the monomeric red fluorescent protein 1 (mRFP1) fusion gene to visualise both the magnocellular and parvocellular OXTergic pathways. OXT‐mRFP1 fluorescence intensity was significantly increased in the PVN, SON, dorsal horn of the spinal cord and posterior pituitary in AA rats. The levels of OXT‐mRFP1 mRNA were significantly increased in the PVN and SON of AA rats. These results suggested that OXT was up‐regulated in both hypothalamic magnocellular neurosecretory cells and parvocellular cells by chronic inflammation, and also that OXT in the PVN‐spinal pathway may be involved in sensory modulation. OXT‐mRFP1 transgenic rats are a very useful model for visualising the OXTergic pathways from vesicles in a single cell to terminals in in vitro preparations. 相似文献