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51.
Radiology of the orbital apex 总被引:1,自引:0,他引:1
The orbital apex, formed by the superior orbital fissure and optic canal, is the cross-road between the orbit and the intracranial structures. Pathological processes may extend intracranially via the superior orbital fissure and vice versa. In addition to intrinsic soft tissue lesions, various pathological processes may involve the surrounding osseous anatomy. Malignant lesions arising from adjacent structures or from haematogeneous metastasis may also infiltrate this region. 相似文献
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烟溶液与温石棉对细胞增殖活性的影响 总被引:3,自引:0,他引:3
目的 探讨香烟烟雾溶液与温石棉单独及联合作用对细胞增殖活性的影响。方法 将人胚肺( H E L) 成纤维细胞用不同浓度的烟溶液和温石棉单独及联合作用一定时间后,应用[3 H] Td R参入法测定了细胞的增殖能力。结果 低剂量的烟溶液与温石棉单独作用时均可促进细胞的增殖,但较高剂量的烟溶液和温石棉则可抑制细胞的增殖;当二者联合作用时,低剂量的烟溶液与温石棉可协同增加细胞的增殖,而较高剂量的烟溶液与温石棉则只表现为相加作用。结论 烟溶液与温石棉单独及联合作用均可影响 H E L细胞的增殖活性,但其促增殖和抑制增殖能力则随剂量不同而不同。 相似文献
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PURPOSE: To investigate a case of isolated pedunculated congenital corneal dermoid. METHODS: Case report. RESULTS: In a 14-day-old infant, the pedunculated portion of the dermoid was removed and confirmed by histopathologic examination. No surgical complication or recurrence was encountered, and the patient is waiting for a rotational autokeratoplasty. CONCLUSIONS: Prompt treatment of such an unusual tumor is important to allow for visual rehabilitation and development. 相似文献
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Ascorbate, often used as an antioxidant in neural studies, may also serve as a neuromodulator in the vertebrate central nervous system (CNS), in that it modulates the synaptic actions of glutamate and dopamine. Retina of fish contain a high concentration of ascorbate. The release and/or uptake of neurotransmitters are related to membrane potential, which to a large extent is determined by the activity of K+ channels. As retinal bipolar cells are subject to synaptic input from glutamatergic and dopaminergic sources, the effects of ascorbate on voltage-dependent K+ currents (I(K)(v)) of the mixed rod-cone ON-center bipolar cells (Mb) in goldfish retinal slices were studied using whole-cell recording techniques. I(K)(V) was suppressed reversibly 60% by 100-200 microM ascorbate. The effect of ascorbate was not due to changes in pH, oxidative stress, lipid peroxidation, any Ca2+-dependent or Na+-dependent action. However, the suppressive effect of ascorbate was blocked by cholera toxin and Wiptide, a protein kinase A (PKA) inhibitor. It is concluded that ascorbate, at physiological concentrations, inhibits I(K)(V) of bipolar cells via a Gs-protein-PKA system. This effect of ascorbate should be taken into account when using ascorbate as an antioxidant in retinal studies involving dopamine. 相似文献
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《四库全书》子部医家类收有《急救仙方》六卷,作者考证后认为,现流传之道藏本《急救仙方》已非原本明正统年间重修《道藏》时篡伪,而原本内容仅见存于八、九两类之中;四库本《急救仙方》则基本保持了原本卷帙的面貌。原本当为宋人所篡,其内容并不局限于外科疮疡,是一部济急便用的综合性方书。 相似文献
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人肺癌相关抗原的基因克隆 总被引:4,自引:0,他引:4
目的克隆人肺癌相关抗原的基因。方法用λgt11Sfi-Not定向克隆载体构建人肺鳞癌细胞系L-78的cDNA文库,并以抗人肺癌单抗ALT-04为探针进行了筛选。对名为hlc-14的cD-NA克隆作了测序分析与进一步研究。用重组的pXJ41-hlc14质粒转染NIH3T3细胞,通过免疫组化法对克隆基因进行了表达检测与鉴定,还观察了转染细胞的软琼脂集落形成能力。结果建成1.4×106pfu/ml人肺癌cDNA文库,经过四轮免疫学筛选获得6个cDNA克隆,最大的cDNA克隆为hlc-14,长954bp。对该克隆的测序结果与基因库资料比较,未发现同源序列。hlc-14cDNA转染的NIH3T3细胞有明显的肺癌相关抗原表达,并且在软琼脂中的集落形成能力增强。结论hlc-14是一个新的肺癌相关抗原的cDNA序列。这一序列的发现为阐明肺癌的发病机理、探索肺癌基因治疗的靶基因提供了新的线索 相似文献
58.
Fan D Poste G Obrian C Seid C Ward N Earnest L Fidler I 《International journal of oncology》1992,1(7):735-742
A variety of resistance phenotypes to cytotoxic agents in bacteria, protozoa parasites and mammalian cells are mediated by evolutionarily conserved proteins of the mdr family. The finding that chloroquine resistance in the malarial parasite, Plasmodium falciparum, that is mediated by an mdr-1 gene product can be circumvented by tricyclic antidepressant drugs has stimulated the present study to assess whether this class of agents might also modulate the multidrug resistance (MDR) phenotype(s) in mammalian tumor cells. The possible chemosensitizing effects of nine antidepressant drugs have been tested against the UV-2237M murine fibrosarcoma line and its MDR variant. At nontoxic concentrations all nine antidepressants markedly enhanced the cytotoxicity of ADR against the parental cells but were much less effective against the MDR cells. The most active antidepressant, trazodone, also enhanced the cytotoxicities of vinblastine and vincristine, but not those of actinomycin D, mitomycin C, or 5-fluorouracil. The parental cells treated with trazodone exhibited an increased accumulation of intracellular ADR, but lacked detectable alterations in the expression and drug-binding activity of plasma membrane P-glycoprotein, and trazodone did not affect the activities of isolated protein kinase C and calmodulin. These data suggest that the antidepressant drug trazodone may be useful in the reversal of the intrinsic drug resistance of tumor cells that express low levels of P-glycoprotein. 相似文献
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