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991.
Effective high-capacity gutless adenoviral vectors mediate transgene expression in human glioma cells. 总被引:2,自引:0,他引:2
Marianela Candolfi James F Curtin Wei-Dong Xiong Kurt M Kroeger Chunyan Liu Altan Rentsendorj Hasmik Agadjanian Lali Medina-Kauwe Donna Palmer Philip Ng Pedro R Lowenstein Maria G Castro 《Molecular therapy》2006,14(3):371-381
Glioblastoma multiforme (GBM) is the most common subtype of primary malignant brain tumor. Although serotype 5 adenoviral vectors (Ads) have been used successfully in clinical trials for GBM, the capacity of Ads to infect human glioma cells and the expression of adenoviral receptors in GBM cells have been challenged. In this report, we studied the expression of three molecules that have been shown to mediate adenoviral entry into cells, i.e., coxsackie and adenovirus receptor (CAR), integrin alphavbeta3 (INT), and major histocompatibility complex class I (MHCI), in rodent glioma cell lines and low-passage primary cultures and cell lines from human GBM. We correlated levels of expression of CAR, INT, and MHCI with transduction efficiency elicited by several high-capacity helper-dependent adenoviral vectors (HC-Ads). Expression levels of adenoviral receptors were variable among the different GBM cells studied. HC-Ad-mediated therapeutic gene expression was efficient, ranging between 20 and 80% of the total target cells expressing the encoded transgenes. Our results show no correlation between the levels of CAR, INT, or MHCI molecules and the levels of transgene expression or the number of GBM cells transduced. We conclude that expression levels of adenoviral receptors do not predict their transduction efficiency or biological function. 相似文献
992.
通过分析高等院校计算机基础教育面临的形势和存在的问题,提出相应的解决办法,同时指出教师必须采用新的教学模式和教学方法,这样才能培养出符合时代需求的新型人才。 相似文献
993.
994.
高等护理毕业生应具备临床护理、护理教育、护理科研、护理管理、社区护理5方面的能力。其授课水平的高低将成为评价高护生护理教育能力的重要指标。我院从2002年起探讨对高护生临床授课的教学模式,以提高授课水平。笔者对2004年-2005年在我院实习的168名高护生进行调查,现将结果报告如下。 相似文献
995.
Tom Rossenbacker MD Sheila J. Carroll MD Huajun Liu MD Cuno Kuipri Thomy J.L. de Ravel FCP Koen Devriendt MD PhD Peter Carmeliet MD PhD Robert S. Kass PhD Hein Heidbüchel MD PhD 《Heart rhythm》2004,1(5):611-615
OBJECTIVES: The purpose of this study was to determine the clinical and biophysical characteristics of a novel SCN5A mutation. BACKGROUND: Brugada syndrome and isolated cardiac conduction defect have been linked to SCN5A mutations. METHODS: Eleven members of a western European family underwent electrophysiologic investigations and mutation analysis of the SCN5A gene. Wild-type and mutant SCN5A channels were expressed in HEK293 cells, and whole cell currents were studied using patch clamp procedures. RESULTS: A novel mutation, R376H, in the first pore segment of SCN5A variably causes Brugada syndrome and/or conduction disease in a single family. Biophysical analysis demonstrated a significant current reduction for the mutant, a pathophysiologic profile consistent with Brugada syndrome and isolated cardiac conduction defect. Among 11 family members, 9 were carriers of the mutation. The proband's initial presentation was a saddleback Brugada ECG, atrial flutter, and diffuse conduction disturbances. He had no inducible ventricular arrhythmias but experienced sudden cardiac death. His brother was affected by atrial flutter and had a clear conduction disorder, but he did not display baseline or evocable ECG signs of Brugada syndrome. He received an implantable cardioverter-defibrillator that delivered one appropriate shock after 1 year of follow-up. The phenotype in the family members was highly variable and ranged from noninducible and inducible asymptomatic carriers of the mutations to isolated conduction disease and to symptomatic Brugada syndrome. CONCLUSIONS: We describe the functional characterization of a novel SCN5A pore mutation, R376H, with variable clinical expression in the same family. Differentiating between electrophysiologic entities (Brugada syndrome-isolated cardiac conduction defect) is more challenging. Recognition of factors modifying the clinical presentation may be important for clinical decision making. 相似文献
996.
Facial spasm, trigeminal neuralgia and stubborn facial paralysis are commonly seen in clinic. The authors have obtained quite good therapeutic results for the above diseases by using the mind-refreshing acupuncture therapy. These are introduced in the following. 相似文献
997.
2型糖尿病(消渴病)微观辨证的临床研究 总被引:4,自引:0,他引:4
目的 为糖尿病的临床辨证、治疗用药提供客观依据和帮助。方法 观察 2型糖尿病 (消渴病 ,diabetesmellitus)不同证型患者各 30例 ,正常对照组 30例 ,检测血清一氧化氮 (NO)、血浆α -颗粒膜蛋白 (GMP 14 0 )、血浆D -二聚体 (D D)、血清白细胞介素 - 6 (IL 6 )这些微观指标的变化 ,探讨其与中医辨证分型的关系。结果 ①血清NO值在各组中的变化是阴虚热盛组 >正常对照组>气阴两虚组 >气滞血瘀组 ,每两组间具有显著性差异 (P <0 0 5 ) ,其中气滞血瘀组与其它 3组具有非常显著性差异 (P <0 0 1)。②糖尿病各组患者血浆GMP 14 0、D D值均较正常对照组有非常显著性增高 (P <0 0 1) ,在糖尿病组各证型中 ,呈阴虚热盛组 <气阴两虚组 <气滞血瘀组变化趋势 ,且血浆GMP 14 0和D D的变化呈正相关 (r=0 6 6 )。③血清IL 6在糖尿病组较正常对照组升高 ,其变化呈阴虚热盛组 <气阴两虚组 <气滞血瘀组趋势 ,每两组间具有非常显著性差异 (P <0 0 1)。结论 糖尿病发病以正气不足为内在依据。随着病程的进展 ,脾肾亏虚及血瘀加重是必然趋势。治疗应重视补脾肾和活血化瘀 相似文献
998.
目的 探讨含碘食物对Graves病患者摄取^99mTc与^131I的影响。方法 选择曾食含碘食物的Graves病患者20例,在禁食含碘食物前后分两次进行摄^131I试验与甲状腺^99mTc显像.前者测定3、24h摄^131I率,后者计算摄锝指数(TI)及估算甲状腺质量(TW)。采用Wilcoxon符号秩和检验对数据进行对比分析。结果 20例患者禁止含碘食物前后的摄^131I率显著不同,所有患者禁食含碘食物后3和24h摄^131I率均显著增高。TI2例未变、2例增高、16例降低;TM18例减小、2例增大。较未禁食含碘食物的首次检测,两者均有显著性变化。结论 含碘食物对甲状腺摄取Na^99mTcO4的影响与Na^131I显著不同,含碘食物100%减低甲状腺^131I的摄取而90%锝摄取增高。 相似文献
999.
眶骨的改变在眶部疾病HR-MRI诊断中的作用 总被引:6,自引:0,他引:6
目的:探讨眶骨的影像学所见及其在眶部疾病诊断中的作用。方法:回顾性分析诊断明确的眶部疾病80例的HR-MRI影像表现。80例中良性囊肿18例,外伤6例,炎性疾病6例,蝶骨嵴脑膜瘤9例,其他肿瘤41例。磁共振扫描采用1.5T GE Signa及Siemens Magnetom Sp63磁共振扫描机,用眶部表面线圈,SE系列常规轴位、冠状位及矢状位扫描,部分病例行脂肪抑制及增强扫描。结果:正常眶骨的HR-MRI表现为结构完整,边缘光整,皮质骨在T1WI及。T2WI上均为无信号区。15例眶骨受压迫性改变全见于良性囊肿的病例,骨质增生改变主要见于蝶骨脑膜瘤,2例骨折见于外伤病例,21例骨质破坏大多见于不同的恶性肿瘤病变中。结论:不同的眶部病变对眶骨的影响有差异,良性囊肿主要表现为眶骨受压迫性改变,蝶骨脑膜瘤多表现为骨质增生,外伤病例伴有眶骨骨折,恶性肿瘤病例常伴有眶骨的破坏。眶骨的改变对眶部疾病HR-MRI的诊断和鉴别诊断有重要作用。 相似文献
1000.
Zhuo Liu Boliang Wang Xiuying Xu Cheng Wang 《Computerized medical imaging and graphics》2006,30(6-7):371-376
This paper constructs two finite element models of human crystalline lens and zonules based on published clinical data. Displacement and pressure were applied to study the mechanism of vision accommodation. The simulation results show that, in Model A, under the pull of the zonules, the thickness of the lens decreased linearly, and the lens diameter increased linearly. The optical power of the lens increased as the zonules displacement increased. Furthermore, the pressure had a remarkable influence on the shape of the lens and the optical power. The lens also became thinner and flatter as the pressure increased. The optical power increased when the pressure increased. In Model B, the lens became thicker and optical power increased as the equatorial zonules stretched. It is basically consistent with Schachar's hypothesis. The outcome of this paper proved that the analytical model presented in this paper can be used in the theoretical study of the accommodation mechanism of the lens. 相似文献