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31.
目的:对地雷伤伤员的截肢残段进行解剖学观察,了解地雷伤的解剖特点,为地雷伤的治疗提供可以借鉴的解剖依据。方法对3段地雷伤截肢残段进行解剖,分离出神经、动静脉,测量肌肉、神经、动静脉长度及出血范围,并取肌肉组织做成切片在镜下观察。结果3段地雷伤截肢残段的大部分肌肉、神经、血管断裂收缩,骨折多呈粉碎性。肌肉组织镜下观察发现,远心端组织结构破坏,肌纤维收缩、破裂、坏死;近心端肌肉组织水肿,大部分肌纤维正常,肌纤维染色浅、纹理模糊。结论地雷伤具有远达效应,地雷爆炸产生的冲击波会沿着伤肢蔓延,造成触雷部位附近的组织撕裂、渗血。  相似文献   
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In the last few years, there have been important new insights into the structural biology of G-protein coupled receptors. It is now known that allosteric binding sites are involved in the affinity and selectivity of ligands for G-protein coupled receptors, and that signaling by these receptors involves both G-protein dependent and independent pathways. The present review outlines the physiological and pharmacological implications of this perspective for the design of new drugs to treat disorders of the central nervous system. Specifically, new possibilities are explored in relation to allosteric and orthosteric binding sites on dopamine receptors for the treatment of Parkinson’s disease, and on muscarinic receptors for Alzheimer’s disease. Future research can seek to identify ligands that can bind to more than one site on the same receptor, or simultaneously bind to two receptors and form a dimer. For example, the design of bivalent drugs that can reach homo/hetero-dimers of D2 dopamine receptor holds promise as a relevant therapeutic strategy for Parkinson’s disease. Regarding the treatment of Alzheimer’s disease, the design of dualsteric ligands for mono-oligomeric muscarinic receptors could increase therapeutic effectiveness by generating potent compounds that could activate more than one signaling pathway.  相似文献   
34.
目的 研究金纳米团簇诱导的小鼠体内毒性是否有性别差异.方法 首先制备谷胱甘肽保护的金纳米团簇(GSH-Au NCs)和牛血清白蛋白保护的金纳米团簇(BSA-Au NCs),然后将48只雌雄各半的昆明鼠随机分为对照组、GSH-Au NCs给药组和BSA-Au NCs给药组.给药组每只小鼠腹腔注射0.2 ml金纳米团簇,对照组注射等量生理盐水;28 d后通过免疫指数、血常规和生化指标来评价金纳米团簇诱导的体内毒性是否有性别差异.结果 2实验组的雌雄小鼠的红细胞和白细胞都有所改变.BSA-Au NCs组的雌性小鼠的胸腺指数有明显增加,其差异有统计学意义(P<0.05).GSH-Au NCs组的雌性小鼠的谷草转氨酶有所升高,BSA-Au NCs组的雄性小鼠的谷丙转氨酶略有升高;2实验组小鼠的肌酐有明显变化,其差异有统计学意义(P<0.05).结论 BSA-Au NCs组的雌性小鼠受到的免疫反应更明显,2实验组的雌雄小鼠受到相似的感染及炎症,雌雄小鼠的肝脏都有所变化,但雌性小鼠比雄性小鼠的肾脏更易受到损害.  相似文献   
35.
Samples of gold soldered assemblies from three different dental casting gold alloys were subjected to various homogenizing heat treatments. The distribution of available alloy components in the region of the gold-solder junction was investigated using electron-probe micro-analysis. An extensive statistical treatment of the data was performed. Concentration differences between casting alloy and solder alloy were not levelled out to any great extent unless after prolonged heat treatment (3 hours) for one of the three alloys. However, this heat treatment caused grain growth and an increased amount of microporosities in the region of the joint. In the soldered assemblies from two of the three casting alloys microphases with a composition different from the original alloys appeared at the gold-solder junction after heat treatment. The results show that homogenizing heat treatment of gold soldered assemblies should not be performed as a routine.  相似文献   
36.
目的 以转铁蛋白(transferrin,Tf)为模板,氯金酸为原料,原位合成靶向荧光探针-内生型转铁蛋白-金纳米簇(gold nanoclusters,AuNCs),并以前列腺癌(prostate cancer,PCa)为模型,探讨该荧光探针的靶向成像效果.方法 利用场发射透射电子显微镜及粒度分析仪分析所合成的荧光探针的形貌、水合粒径及分布;利用紫外-可见分光光度计及荧光分光光度计对其光学性能进行表征;MTT法检测细胞毒性;并通过细胞荧光成像及竞争抑制实验表征其肿瘤的特异性靶向效果;静脉注射Tf-AuNCs至PC-3种植瘤鼠体内,进行连续荧光成像,评价其肿瘤靶向成像效果;通过组织病理学明确其活体毒性.结果 本研究制备的Tf-AuNCs粒径约为3 nm,荧光发射峰为700 nm,保留了Tf及金纳米簇的性能;细胞成像结果显示Tf-AuNCs对前列腺肿瘤细胞(PC-3)特异性靶向效果好;小动物活体成像结果显示Tf-AuNCs探针仅需15 min即可准确显示肿瘤部位,至2h时肿瘤区荧光强度达峰值,表明其具有良好的活体肿瘤成像能力;病理学结果表明Tf-AuNCs具有良好的生物相容性.结论 Tf-AuNCs荧光探针具有良好的光学性能、特异靶向能力,并具有优异的荧光成像能力及良好的生物相容性,将有望应用于PCa的早期影像学分析.  相似文献   
37.
Gold nanorods (GNRs) are used for their wide variety of applications in various industries. There is a little availability of data related to toxicity and ecological implications of these GNRs. The study evaluated the oxidative stress induction following intra-tracheal instillation of 1 and 5?mg/kg b.w. doses of 10 and 25?nm GNRs by estimating various oxidative stress markers including lipid peroxidation (malondialdehyde; MDA), glutathione (GSH), superoxide dismutase (SOD), catalase and total antioxidant capacity (TAC) after 1?day, 1?week, 1?month, and 3?months post exposure periods. The results have shown increased MDA levels and decreased GSH levels following 1?day and 1?week post exposure periods, indicating induction of oxidative stress. Also, the SOD, catalase and TAC levels were significantly decreased following exposure of both 10 and 25?nm GNRs after 1?day and 1?week after exposures, indicating the inhibition of antioxidant defense mechanisms. Moreover, the 10?nm GNRs at 5?mg/kg dose displayed greater changes in all the estimated parameters, representing dose and size based induction of oxidative stress by GNRs. In contrast, a little change was observed during 1?month and 3?months post exposure periods, may be due to recovery. Finally, the GNRs induced dose-size-dependent oxidative stress induction by various oxidative stress markers following intra-tracheal instillation in rats.  相似文献   
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Concerns about the bioaccumulation and toxicity of gold nanoparticles inside humans have recently risen. HT-29 and HepG2 cell lines and Wistar rats were exposed to 10, 30 or 60 nm gold nanoparticles to determine their tissue distribution, subcellular location and deleterious effects. Cell viability, ROS production and DNA damage were evaluated in vitro. Lipid peroxidation and protein carbonylation were determined in liver. ICP-MS measurements showed the presence of gold in intestine, kidney, liver, spleen, feces and urine. Subcellular locations of gold nanoparticles were observed in colon cells and liver samples by transmission electron microscopy. Inflammatory markers in liver and biochemical parameters in plasma were measured to assess the inflammatory status and presence of tissue damage. The size of the nanoparticles determined differences in the biodistribution and the excretion route. The smallest nanoparticles showed more deleterious effects, confirmed by their location inside the cell nucleus and the higher DNA damage.  相似文献   
40.
Timely detection is crucial for successful treatment of cancer. The current study describes a new approach that involves utilization of the tumor cell environment for bioimaging with in-situ biosynthesized nanoscale gold and iron probes and subsequent dissemination of Au-Fe nanoclusters from cargo exosomes within the circulatory system. We have isolated the Au-Fe cargo exosomes from the blood of the treated murine models after in situ biosyntheses from their respective pre-ionic solutions (HAuCl4, FeCl2), whereas Na2SeO3 supplementation added into Au lethal effect. The microarray data of various differentially expressed genes revealed the up-regulated tumor ablation and metal binding genes in SGC-7901 cell lines after treatment with Au-Fe-Se triplet ionic solution. The isolation of Au-Fe nanoclusters cargo exosomes (nano in nano) after secretion from deeply seated tumors may help in early diagnosis and reveal the tumor ablation status during and after the relevant treatment like radio-chemo therapies et al.  相似文献   
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