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排序方式: 共有98条查询结果,搜索用时 15 毫秒
1.
Ge-132对小鼠H22肝癌移植瘤的实验研究证明:1.Ge-132对H22肝癌移植瘤有一定的抑制作用,300mg/kg体重剂量抑瘤率达到36.19%;2.增强机体的抗氧化作用,抑制脂质的过氧化物水平;3.促进免疫功能,当Ge-132和环磷酰胺联合使用时,可抵抗环磷酰胺的免疫抑制作用,而且并不减弱其抑制瘤作用。  相似文献   
2.
利用火焰原子吸收法直接测定羊睾丸,梅花鹿胎盘提取液中铅的含量,实验结果表明,两种提以液中均含有铅,梅花鹿胎盘提取液铅含量低于羊睾丸,透析液组高于超滤液组,这一结果为合理开发利用羊睾丸,梅花鹿胎盘提取液提供一定的数据。  相似文献   
3.
Neonatal exposure to synthetic estrogen endocrine disruptors or estrogen-receptor inhibitors induces developmental abnormalities in the male reproductive system. To investigate whether neonatal exposure affects spermatogenesis in juvenile and pubertal testis, Sprague-Dawley rat pups were given synthetic estrogen endocrine disruptors or estrogen-receptor inhibitors by a single injection on the day of birth at concentrations ranging between 2 to 40 mm, and sacrificed on day 21 (juvenile), 35 (prepuberty) or 50 (puberty). The testes were weighed and examined histologically at each stage. Further, the metabolites of steroidogenesis were analyzed using normal-phase high performance liquid chromatography. Neonatal exposure significantly reduced testis weights and steroidogenesis to one- fifth to one-half of that of the juvenile control, and further suppressed irreversible steroidogenesis and spermatogenesis during puberty.  相似文献   
4.
Alzheimer's disease (AD) is a progressive neurodegenerative disorder that is the most common cause of dementia in aging populations. Although senile plaques and neurofibrillary tangles are well-established hallmarks of AD, changes in cerebral white matter correlate with cognitive decline and may increase the risk of the development of dementia. We used the triple transgenic (3xTg)-AD mouse model of AD, previously used to show that white matter changes precede plaque formation, to test the hypothesis that MRI detectable changes occur in the corpus callosum, external capsule and the fornix. T2-weighted and diffusion tensor magnetic resonance imaging and histological stains were employed to assess white matter in older (11–17 months) 3xTg-AD mice and controls. We found no statistically significant changes in white matter between 3xTg-AD mice and controls, despite well-developed neurofibrillary tangles and beta amyloid immunoreactive plaques. Myelin staining was normal in affected mice. These data suggest that the 3xTg-AD mouse model does not develop MRI detectable white matter changes at the ages we examined.  相似文献   
5.
Human Mammary Tumor Virus (HMTV) or Mouse Mammary Tumor Virus holds similarity as an endogenous onco-retrovirus belongs to retroviridae family, predominantly infects the epithelial cell of human as well as mouse. With the recognition of nano-biosensor in nanotechnology, ideal interdigitated electrode (IDE) was genuinely performed for HMTV detection. Aluminium enriched IDE (AlIDE) was fabricated for high performance detection with a cost-effective photolithography technique. In this research, (3-glycidyloxypropyl) trimethoxysilane refined platform was selected to detect the conductivity with HMTV target DNA interaction on the designed AlIDE. Strong binding affinity of streptavidin-biotin with target DNA enhanced the sensitivity by empowering higher number of HMTV probe and target complementation on sensing surface. Furthermore, the target DNA was immobilized on probe modified AlIDE and a quantitative value of 100 aM attained as a lowest detection. A linear with dose-dependent duplex formation was shown with the regression coefficient value of 0.964. Negative control has shown insignificant detection at 10 pM, which justifies the higher fold discrimination with specificity. The excellence of AlIDE performance in detection of HMTV may pave the way for more verification on other diseases.  相似文献   
6.
ICP-MS法测定鼠脊髓液中超痕量镧、铈、镨和钕   总被引:2,自引:0,他引:2  
采用NHO3+HClO4混合酸溶样,感耦等离子体-质谱(ICP-MS)直接测定鼠脊髓液中La、Ce、Pr和Nd,对等离子体质谱测定条件进行了最佳化选择。选用铼(Re)内标可补偿基体影响和仪器漂移。方法检出限为7.6-20.3ng/L,加标试验回收率为94%-102%,相对标准偏差(RSD)为2.1%-3.7%。  相似文献   
7.
双光子激发荧光成像技术对小鼠植入前胚胎的实时观测   总被引:3,自引:1,他引:3  
双光子激发的蓝移效应可使利用同一束超快激光同时激发多种不同荧光特性的生物荧光染料的设想得以实现。选取锁模飞秒掺钛蓝宝石(Ti-sapphire)激光器输出的730nm激光,分别激发Hoechst33342,Fluo-4,PI和Indo-1四种常用生物荧光染料,分别利用(455±15)nm,(540±15)nm,(580±16)nm和(500±15)nm四种滤光片获得特异性荧光图像。结合双光子激发荧光成像技术穿透深,光损伤小,信噪比好等优势,选取合适的荧光染料组,应用单束激光激发、双染双通道成像方法,对小鼠植入前胚胎内细胞中的钙信号和染色体进行三维、四维实时成像,为探究小鼠植入前胚胎发育规律提供一种全新的多参数观测手段。  相似文献   
8.
探究模拟微重力条件下不同剂量C离子辐射对雄性动物生殖器官的急性影响, 以期了解空间环境辐射所致机体生殖系统的损伤。采用小鼠尾部悬吊模型地面模拟微重力状态1周后, 利用重离子加速器提供的C离子辐照处理, 检测了生殖器官脏器系数及精子密度、组织形态变化、DNA损伤以及细胞凋亡各项指标。结果表明, 微重力和C离子辐射均能引起睾丸损伤, 且1 Gy单纯辐照组中损伤最为严重。此外发现, 模拟微重力能够在一定程度上降低辐射诱导的损伤, 其内在机制有待于进一步的研究。In this paper it was investigated that the effect of modeled microgravity on the acute injury induced by low doses of carbon ions in the male reproductive organs of mice, assessing the risk associated with the space environments. In our study, outbred Kunming mice were stimulated in microgravity by tail suspension, and then were irradiated with the low doses of carbon ions diliuered by HIRFL, and measured the testis and epididymis coefficient, sperm number of epididymis, histological alterations, DNA strand breaks and cell apoptosis. The results demonstrated that carbon ions and stimulated microgravity could induce the damage in the present study. Moreover, most serious injury all occurred in the irradiation group. In addition, it was also found that the damage of the carbon ion irradiation combined microgravity group were lower than those of the irradiation group, while the related mechanism needs the further investigation.  相似文献   
9.
A capillary electrophoresis method with in‐column light‐emitting diode induced fluorescence detection is described for simultaneous determination of D ,L ‐serine in the midbrain of a Parkinson's disease mouse. D ,L ‐Serine was derivatized with fluorescein isothiocyanate, and chiral separation and determination of D ,L ‐serine derivatives were performed on a laboratory‐built capillary electrophoresis system with in‐column light‐emitting diode induced fluorescence detector using γ‐cyclodextrin as chiral selector. Using this method, the levels of D ‐ and L ‐serine in the midbrains of Parkinson's disease mice were determined. When compared to controls, the levels of D ‐ and L ‐serine showed significant differences. The result suggested that the biosynthesis and the transportation of endogenous D ,L ‐serine may participate in Parkinson's disease pathogenesis.  相似文献   
10.
In the present study, novel representatives of the important group of biologically-active, dehydroabietic acid-bearing dithiocarbamate moiety, were synthesized and characterized by 1H NMR, 13C NMR, HR-MS. The in vitro antiproliferative activity evaluation (MTT) indicated that these compounds exhibited potent inhibitory activities in various cancer cell lines (HepG-2, MCF-7, HeLa, T-24, MGC-803). Particularly, compound III-b possessed extraordinary cytotoxicity with low micromolar IC50 values ranging from 4.07 to 38.84 µM against tested cancer cell lines, while displayed weak cytotoxicity on two normal cell lines (LO-2 and HEK 293 T). Subsequently, the potential mechanisms of representative compound III-b were elementarily investigated by Transwell experiment, which showed III-b can inhibit cancer cells migration. Annexin-V/PI dual staining showed that the compound can induce HepG-2 cells apoptosis in a dose-dependent manner. Meanwhile this apoptosis may be related to the upregulated protein expression of cleaved-caspase 3, cleaved-caspase 9, Bax and downregulated of Bcl-2 indicated by Western Blot. Later study further confirmed that ROS levels in HepG-2 cells increased significantly with the rise of concentrations. In addition, through the network pharmacology data analyzing, the core targets and signaling pathways of compound III-b for treatment of liver neoplasms were forecasted. Molecular docking model showed that compound III-b had high affinity with hub targets (CASP3, EGFR, HSP90AA1, MAPK1, ERBB2, MDM2), suggesting that compound III-b might target the hub protein to modulate signaling activity. Taken together, these data indicated that dehydroabietic acid structural modification following the “Molecular hybridization” principle is a feasible way to discover the potential multi-targeted antitumor compounds.  相似文献   
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