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991.
992.
激光扫描共聚焦显微镜的原理与生物学应用 总被引:8,自引:0,他引:8
激光扫描共聚焦显微镜在光学显微镜基础上结合了激光和计算机图象处理技术,把光学显微镜的分辨率提高了30-40%,其光学切片性能使观察组织、细胞的三维结构成为可能。本文简要介绍了共聚焦显微镜的历史和成象原理,着重介绍了其在生物学领域的应用,如样品的三维定量测量及活细胞的动态信号监测,并结合新兴的光生物学技术,如光镊、笼锁化合物的解笼锁、细胞分选、光漂白后的荧光恢复,探讨了激光共聚焦显微镜在激光细胞生物学的应用前景 相似文献
993.
994.
目的 寻找新的抗万古霉素耐药菌活性化合物。方法 首次采用固相法合成了分别用生物素(Biotin)和^125I标记的D-Ala-D-Lactate和D-Ala-D-Ala探针化合物以及18个结构限定性的多肽和多肽衍生物化学库,并建立了“一珠一化合物”组合正交筛选实验方法。结果 发现了一个新的体外抑制低水平万古霉素耐药菌的化合物(Enterococcus faecalis,ATCC 51299,MIC值为17.5mg/L)。该化合物对万古霉素敏感菌菌株的抑制活性为MIC6.25mg/L(Staphylococcus aurreus,ATCC 25923)。结论 “一珠一化合物”组合正交筛选方法可以用于研究小分子间的相互作用。 相似文献
995.
Transient cochlear ischemia causes delayed cell death in the organ of Corti: an experimental study in gerbils 总被引:4,自引:0,他引:4
Koga K Hakuba N Watanabe F Shudou M Nakagawa T Gyo K 《The Journal of comparative neurology》2003,456(2):105-111
To elucidate whether ischemia-reperfusion can cause delayed cell death in the cochlea, the effects of transient cochlear ischemia on hearing and on neuronal structures in the cochlea were studied in Mongolian gerbils. Ischemia was induced by bilaterally occluding the vertebral arteries for 5 minutes in gerbils, which lack posterior cerebral communicating arteries. In gerbils, the labyrinthine arteries are fed solely by the vertebral arteries. Occlusion of the vertebral arteries caused a remarkable increase in the threshold of compound action potentials (CAPs), which recovered over the following day. However, 7 days after the onset of reperfusion, the threshold began to increase again. Morphologic changes in the hair cell stereocilia were revealed by electron microscopy. The number of nuclear collapses was counted in cells stained for DNA and F-actin to evaluate the degree of cell death in the organ of Corti. Changes in spiral ganglion cell (SGC) neuron number were detected, whether or not progressive neuronal death occurred in the SGC. These studies showed that sporadic fusion of hair cells and the disappearance of hair cell stereocilia did not begin until 4 days after ischemia. On subsequent days, the loss of hair cells, especially inner hair cells (IHCs), and the degeneration of SGC neurons became apparent. Ten days after ischemia, the mean percentage cell loss of IHCs was 6.4% in the basal turn, 6.4% in the second turn, and 0.8% in the apical turn, respectively, and the number of SGC neurons had decreased to 89% of preischemic status. These results indicate that transient ischemia causes delayed hearing loss and cell death in the cochlea by day 7 after ischemia. 相似文献
996.
A synthetic heparin-mimicking polyanionic compound inhibits central nervous system inflammation 总被引:6,自引:0,他引:6
Irony-Tur-Sinai M Vlodavsky I Ben-Sasson SA Pinto F Sicsic C Brenner T 《Journal of the neurological sciences》2003,206(1):49-57
The immunomodulating capacity of heparin led us to test the effect of the synthetic heparin-mimicking and low anticoagulant compound RG-13577 on the course of experimental autoimmune encephalomyelitis (EAE) and central nervous system (CNS) inflammation. EAE was induced in SJL mice by inoculation with whole mouse spinal cord homogenate. RG-13577, delivered intraperitoneally, inhibited the clinical signs of acute EAE and markedly ameliorated inflammation in the spinal cord, primarily by inhibiting heparanase activity in lymphocytes and astrocytes and thus impairing lymphocyte traffic. RG-13577 treatment was effective when started on day of disease induction or day 7 after induction. The low molecular weight heparin, enoxaparin, tested under the same conditions, exerted only a minor insignificant inhibitory effect. RG-13577 also inhibited the tyrosine phosphorylation of several proteins, particularly Erk1 and Erk2 of the MAP kinase signaling pathways associated with inflammation and cell proliferation. RG-13577 blocked the activity of sPLA(2) and inhibited CNS PGE(2) production both in vivo and in vitro. 相似文献
997.
In this study, sociodemographic, laboratory, and clinical features of cases of organic phosphorus (OP) intoxication in the Southeast Anatolian region of Turkey were investigated. Patients with OP intoxication admitted to the Emergency Service of Dicle University Hospital in Diyarbakyir City between May and August 1998 were evaluated. This prospective cohort study included five male (M) and 19 female (F) consecutive patients. Five cases were accidental intoxication; however, 19 cases were suicide attempts. Mean age of cases was 24+/-11 years; 54.2% of them were under the age of 20 years and 83.3% of them were under the age of 30 years. The M/F ratio was 1.0/3.8. The cases of suicidal purposeful intoxications were mostly determined in singles (58.3%, P<0.05). Most of the cases had a primary education level (16, 66.7%) and a lower socioeconomic status (14, 58.3%); 79.2% of cases admitted to our emergency service received atropine in primary health care centers. In emergency service, pralidoxime (PAM) was administered to only 29.2% of cases. According to ECG examination, tachycardia (14, 58.3%), ST changes (13, 54.2%), and T changes (3, 12.5%) were mostly seen; bradycardia and serious ventricular arrhythmias were not seen in any case. Patients who received atropine plus PAM had higher rates of arrhythmias, but this was not statistically significant (P>0.05). The most observed biochemical features of cases were leukocytosis (21 cases), hypokalemia (18 cases), and hyponatremia (4 cases). Other biochemical features were not evidently altered. In present cases, the most frequently seen symptoms and findings were vomiting (18, 75%), feeling faint (17, 70.8%), and tachycardia and dozing off (14, 58.3%). Serious ventricular arrhythmias were not observed, and in our region, OP intoxication especially affected young unmarried females, and most of them resulted from a suicidal purpose. 相似文献
998.
将 1 33例热咳患者随机分成两组 ,治疗组 98例予以柴胡清肺合剂治疗 ,对照组 35例予以复方可待因糖浆治疗 ,疗程均为 2周。结果 :治疗组总有效率为 94 8% ,对照组为 54 7% ,差异有显著性意义 (P <0 0 0 1 )。提示柴胡清肺合剂治疗热咳有待好疗效。 相似文献
999.
复方半枝莲胶囊体外抗肿瘤作用的实验研究 总被引:2,自引:0,他引:2
目的观察复方半枝莲胶囊体外抗肿瘤作用。方法采用活细胞计数法、MTT法、集落形成试验观察其对人肝癌细胞、人宫颈癌Hala细胞及人胃癌细胞的体外抑瘤作用。结果复方半枝莲胶囊对上述三种人癌细胞的生长增殖曲线具有明显的抑制作用;对三种人癌细胞降解MTT半数抑瘤浓度(IC50)分别为1.05mg/mL、0.75mg/mL、1.08mg/mL对三种人癌细胞的集落形成有明显的抑制作用,最大抑制率分别为45.16%、68.42%、45.31%。结论复方半枝莲胶囊体外具有明显的抗肿瘤活性。 相似文献
1000.
白松片对抑郁模型大鼠海马神经元睫状神经生长因子及其mRNA表达水平的影响 总被引:2,自引:0,他引:2
目的观测白松片对抑郁模型大鼠海马睫状神经生长因子(CNTF)及其mRNA表达水平的影响,探讨白松片的抗抑郁作用的机制。方法将大鼠随机分为正常组、模型组、白松片组、氟西汀组,采用连续21d慢性轻度不可预见性应激配合孤养复制抑郁模型。运用免疫组化和原位杂交方法探讨白松片对抑郁模型大鼠海马神经元细胞CNTF、CNTFmRNA表达的影响。结果白松片组大鼠海马神经元CNTF免疫反应阳性细胞数目增多,神经元平均灰度值降低,其中CA1区(105.14±7.21),CA3区(104.47±6.05),DG区(108.18±7.56);CNTFmRNA杂交阳性信号增加,神经元平均灰度值降低,其中CA1区(182.14±12.68),CA3区(176.82±11.12),DG区(175.98±12.15)。与模型组比较,差异有显著性(P<0.05或P<0.01)。结论白松片增加抑郁模型大鼠海马CNTF、CNTFmRNA的表达,可能是其抗抑郁作用的分子机制之一。 相似文献