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Chuan-Bin Guo Nian-Hui Cui Guang-Yan Yu Ding-Xin Liu Shu-Cong Meng Qing Song 《Journal of oral and maxillofacial surgery》2003,61(8):909-912
PURPOSES: Inhibition of cerulenin on the endogenous fatty acid synthetic activities of oral squamous cell carcinoma (OSCC) and normal oral mucosa was assayed. METHODS: Squamous cell carcinoma and normal oral mucosa were collected fresh from surgical specimens. The collected tissues were minced in RPMI 1640 and divided into 3 groups: cerulenin treated, dimethylsulfoxide treated, and control. The tissues were incubated in [1(2)-(14)C]acetic acid, sodium salt for the last 2.5 hours of the treatment at 37 degrees C in 5% CO(2). After labeling, total lipids were extracted and counted for (14)C by scintillation counting. RESULTS: Endogenous fatty acid synthetic activities of oral squamous cell caranoma in the cerulenin-treated group decreased by 19% at 1 hour, 64% at 2 hours, and 87% at 4 hours; remained nearly unchanged in the dimethylsulfoxide-treated group; and increased slightly in the control group. The oral mucosa tissues were only mildly affected by cerulenin in fatty acid synthesis. CONCLUSIONS: Cerulenin significantly inhibits fatty acid synthetic activity in squamous cell carcinoma and only mildly affected the oral mucosa, indicating that the fatty acid synthetic pathway may be exploited as a target for developing anticancer drugs. 相似文献
84.
BACKGROUND: In recent years some reports have been published propagating microsurgical resection of ventral foramen magnum meningiomas (VFMMs). Operative approaches to these lesions have been studied by various authors, but remain controversial.
OBJECTIVE: To discuss the operative technique and outcome in patients with VFMMs who had been treated via a far lateral suboccipital approach.
DESIGN: Retrospectively clinic case investigation.
SETTING: Department of Neurosurgery, the Ninth People's Hospital, Medical School of Shanghai Jiao Tong University.
PARTICIPANTS: Between January 1997 and June 2003, 10 patients were treated surgically with VFMMs in Department of Neurosurgery, the Ninth People's Hospital, Medical School of Shanghai Jiao Tong University. In the series of 10 patients, ages ranged from 37 to 72 years, mean (53±10) years, were consisted of 6 males and 4 females. All the subjects were informed of the treatment plan and agreed to join the experiment. Early symptoms included headache and upper cervical pain. The time between the first occurrence of symptoms and the diagnosis ranged from 6 months to 17 months, mean (10.3±3.4) months. Main presenting symptoms were unilateral upper extremity sensory and motor deficits in 6 cases, swallowing difficulties in 2 and spastic quadriparesis in 2. VFMMs were demonstrated as round by the computed tomographic (CT) scan and magnetic resonance imaging (MRI) in all patients. The maximum diameter of tumors ranged from 2 to 4 cm, mean (2.55±0.57) cm, including 2 cm in one case, 2.0-3.0 cm in six and 3.0-4.0 cm in three.
METHODS: ①All tumors were removed via the far lateral suboccipital approach. Resection of the posterior 5 mm of the condyle was necessary in one patient whose tumors' diameter were 2 cm. The patient was situated in the lateral decubitus position. The head was fixed in a Mayfield headrest. A C-shaped incision made behind the ear 2 cm medial to the mastoid process, turning vertically down to the level C4, to expose the extradural segment of the vertebral artery (VA). After the dura was opened longitudinally behind VA entry point, the tumor was revealed to identify the complete cranial nerves and the intracranial VA under magnification of the surgical microscope. Every attempt should be made to keep the arachnoid and the dentate ligament was sectioned. Then the tumor was debulked significantly, and dissected away from the cranial nerves and the blood vessels with microsurgical techniques. If it was risk to dissect tumor from the vertebral artery, its branches, or any cranial nerve, the progression was discontinued and portion of the tumor was left behind. After resection of the tumor, the site of its attachment was coagulated and the involved layer of dura was resected. ②The degree of tumor resection was classified based on Al-Mefty's grade into three categories: gross-total resection: excision of the dural attachment and drilling of adjacent bone; near-total resection: a few millimeters of insulated and cauterized tumor were left on the vertebral artery or other vital; subtotal resection: more than 50% of the tumor mass were removed. ③All patients underwent clinical examination for lower cranial nerves or long tract deficits on the first day postoperatively. CT or MRI and neurological examinations were performed at 3 months of follow-up.
MAIN OUTCOME MEASURES: Operative effect.
RESULTS: All ten patients with VFMMs were treated via a far lateral suboccipital approach. Gross total resection was achieved in 6 patients, near-total resection was carried out in 2 and subtotal resection in 2 patients. One patients died in the postoperative period due to acute respiratory distress syndrome, five patients kept normal neurological status, whereas other four patients suffered from lower cranial nerve deficits and aspiration pneumonia was observed in two of them. The data of following up for 3 months showed that 2 patients still had lower cranial nerve deficit and others recovered from their illness. No tumor relapse or increment was found in CT or MRI scans.
CONCLUSION: Most of VFMMs could be totally removed via a far lateral suboccipital approach with or without resection of the occipital condyle according to the tumor size, allowing most of these patients to achieve a good outcome in a 3 months follow-up. 相似文献
85.
目的探讨小肝细胞癌的CT影像表现。方法回顾我院2001年2月-2005年2月经病理证实的12例小肝细胞癌的CT表现。结果通过平扫、动脉期、门脉期及部分延迟扫描均可对小肝细胞癌作出定性诊断。结论螺旋CT作为非创伤性容积扫描技术对小肝细胞癌的早期检出、定位、定性诊断具有十分重要的临床价值。 相似文献
86.
岛状皮瓣静脉淤血再通后对大鼠全身情况的影响 总被引:4,自引:0,他引:4
目的:探讨岛状皮瓣静脉淤血再通后对全身多脏器的影响。方法:按静脉淤血时间的不同将大鼠分为4组。观察耳部微循环的改变,测量术后肿瘤坏死因子α(TNFα),白细胞介素10(IL-10)的动态变化,观察心,肺,肝,肾,小肠及耳部血管等组织结构及中性粒细胞浸润数目。结果:皮瓣原位缝合组及静脉淤血2h组,耳部微循环、TNFα、IL-10浓度基本保持不变,各脏器结构改变较轻,中性粒细胞浸润数目少。静脉淤血6、10h组,微循环,肺,小肠,血管则有明显组织学改变,大量中性粒细胞浸润其中,但心,肝,肾组织学改变较轻。TNFα浓度再灌注1h达到高峰,其后逐渐下降,IL-10浓度3h达到最低,然后逐渐上升。结论:皮瓣静脉淤血再通后可造成肺、小肠及血管器官损伤,静脉淤血时间越长,再通后则损伤程度越重。全身微循环的改变,中性粒细胞在肺、小肠中的浸润,与血管内皮细胞的粘附及细胞因子TNFα与IL-10的浓度失衡是重要的操作原因。 相似文献
87.
88.
目的探讨不同视场角参数对虚拟环境中目标判断的影响规律 ,找出最佳视场角参数。方法利用自行研制基于PC平台的虚拟现实 (VR)实验系统 ,选定 45名年龄在 2 3~ 5 8岁被试者并完成大小与角度判断的实验设计。首先进行 30 0人次的预实验 ,确定引起虚拟环境中目标判断差错的视场角及相应观察任务的差别等级 ,然后开始单因素、4水平的完全随机正式实验。结果方差分析表明 ,不同的虚拟环境视场角对目标判断的真实性有显著性影响 ,当视场角为 60°时 ,目标判断的正确率最大。结论利用VR技术进行载人航天器工效设计、操作训练或其它任务的研究时 ,应考虑视场角的作用 ,适合目标大小判断的视场角参数值宜取 60°,以便获得最大的工效 相似文献
89.
对某镍业公司车间空气中镍浓度和工人指甲镍含量进行了测定。按照生产过程和卫生学特点,将所获数据划分为碎矿压球、电炉转炉和汽车维修三组。空气镍浓度几何均值分别为0.0978、0.0623和0.0202mg/m~3;工人指甲镍几何均值分别为23.04、21.07和4.84μg/g;两者呈现一定的接触水平-反应关系。表明以指甲镍作为职业性接镍人群的生物监测指标有一定的参考价值。 相似文献
90.
目的 探讨富氧对高原人体运动心力储备方面的影响。方法 对海拔 3 70 0m高原的 1 2名健康青年富氧 (氧浓度为 2 4%~ 2 5 %)前后分别进行踏阶运动 ,采用心力监护仪采集和记录心动周期和心力信息 ,把完成规定运动量运动后第一心音 (S1 )幅值对安静时S1 幅值增加的相应倍数评估心肌收缩能力储备指数 (CCRI) ;利用舒张期和收缩期时限数据计算舒张期 /收缩期比值 (D/S比 )。结果 运动后较安静时HR ,D/S ,S1 幅值均增高 ,有非常显著性差异 (P <0 .0 1 ) ;富氧运动较未富氧运动CCRI,D/S ,S1 幅值增高 ,有显著性差异 (P <0 .0 5 ) ,HR无统计学意义 (P >0 .0 5 )。结论 高原低氧环境下心脏储备主要是心肌收缩能力储备而不是心率储备。富氧对增强机体心力储备具有重要作用 相似文献