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131.
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   
132.
目的 研究皮质类固醇激素调节小鼠哮喘模型树突细胞表面共刺激分子表达的机制,以及肺表面活性蛋白A(SP-A)在其调节中的作用。方法 BALB/c小鼠30只,分为3组:哮喘组,采用卵蛋白(OVA)致敏和激发;对照组,以生理盐水代替OVA;治疗组,每次OVA激发后10min,腹腔注射地塞米松01mg。用免疫组化法检测SP-A在肺内的表达情况。采用Leica DM Snk软件进行图像采集,并用Qwin软件计算小气道内棕色区域面积,取平均值,进行统计分析。分离培养脾脏树突细胞,用流式细胞仪(FACS)检测树突细胞表面共刺激分子CD80的表达变化。结果 哮喘组肺组织表现为嗜酸性细胞及淋巴细胞浸润为主的炎症变化,治疗组和对照组无此变化。哮喘组的SP-A表达明显低于对照组和治疗组(P〈0.01),CD80的表达率明显高于治疗组(P〈0.01);哮喘组小气道内SP-A表达与树突细胞CD80阳性率呈负相关(r=-0.907,P〈0.01)。结论 皮质类固醇对小鼠哮喘模型的肺表面活性蛋白有明显的保护作用,可通过激发肺表面活性蛋白抑制树突细胞表面共刺激分子CD80的表达。  相似文献   
133.
Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inorganic anions were roughly proportional to lyotropic Hofmeister swelling abilities of the anions; F?<SO4 2?<Cl? <ClO4 ?<NO3 <SCN? <Br <I?, i.e. l, Br and SCN increased the flux of drugs through the mouse skin, while F?, SO4 2?, Cl?, ClO4 ? and NO3 ? decreased or did not affect the flux. In invivo experiment using the rabbit as the test animal, the plasma concentration of salicylic acid of the rabbit to which 10%-salicylic acid ointment containing 5%-Nal or NaBr was applied was significantly higher than that of the rabbit to which the ointment without the electrolytes was applied. The amounts of sterol leached out of stratum corneum sheet when the sheet was immersed in aqueous solutions of Nal, NaBr, or NaSCN were much more than that of stratum corneum immersed in aqueous solutions of the other inorganic anions. The FTIR/ATR spectroscopy showed that the peaks at 2853 cm?1 and 2924 cm?1 in the IR absorption spectrum of the stratum corneum sheet of the mouse were shifted to higher frequencies by the anions which enhanced the transdermal drug permeation, while not shifted by the anions which did not have any permeation-enhancing activities or have permeation-reducing activities. These results suggest that sodium salts of some anions such as iodide, bromide and thiocyanate enhance transdermal permeation of salicylic acid through swelling and perturbation of the skin structure by these anions.  相似文献   
134.
135.
应用计算机化清醒大鼠血流动力学测定技术,观察5-HT2受体阻滞剂Ritanserin(Rit)和α1受体阻滞剂哌唑嗪对清醒自发性高血压大鼠(SHR)的血压、血压波动性(BPV)和动脉压力感受性反射血压控制部分(ABR-BP)的效应,旨在初步探讨兼具5-HT2受体和α1受体阻滞作用地新型抗高血压药Ketanserin降低BPV的机制。结果表明:Rit对SHR无降压作用,但侧脑室给药明显提高ABR-B  相似文献   
136.
137.
研究目的调查分析出院后精神分裂症患者的心理状况,了解存在的问题并探讨解决的对策。研究方法对77例出院后精神分裂症病人就22项心理问题进行调查统计,并对比男女患者差异。结果男性易发脾气、借酒消愁、因病影响工作安排的现象较女性突出,而女性的婚姻状况较紧性明显。结论社区防治的病人心理问题较繁杂,因此防治工作应重视患者的心理特点,解决患者的实际问题。  相似文献   
138.
Increased leucocyte Na+/H+ antiport activity has previously been demonstrated in both hypertensive subjects and Type 1 diabetic patients with nephropathy and may indicate a predisposition to hypertension in such diabetic patients. We have studied intracellular pH and Na+/H+ antiport activity in cultured skin fibroblasts from diabetic patients with and without nephropathy, together with non-diabetic controls to assess if such differences persisted in cultured cells. Fibroblasts from diabetic patients with nephropathy were significantly more alkaline [median (range): 6.90 (6.82 to 7.07)] compared to both normoalbuminuric diabetic patients [6.81 (6.75 to 6.89)] or normal controls [6.82 (6.77 to 6.93)] (P < 0.001 for both). This was associated with a raised Na+/H+ antiport activity in cells from patients with nephropathy when intracellular pH (pHi) was clamped to pH 6.5, without any differences in the maximal transport capacity of the antiport at pHi 6.2. Using both intracellular pH and Na+/H+ antiport activity at pHi 6.5, patients with nephropathy were separated from uncomplicated subjects with a sensitivity of 92% and a specificity of 100%. In conclusion, the raised Na+/H+ antiport activity in cells from patients with diabetic nephropathy persists despite passaging in vitro, thus indicating a heritable component, and results mainly from an increased apparent affinity of the antiport for intracellular H+.  相似文献   
139.
Background Previous studies have noted that there is a high utilization rate of traditional Chinese medicine (TCM) services in Taiwan, China and in western countries, but few studies investigated factors associated with the utilization of TCM in Taiwan. This study analyzes the utilization rate and the factors associated with the utilization of TGM in Taiwan. Methods Data for this study were from the 2002 HPKAP Survey that conducted the face-to-face questionnaire interviews of people aged 15 years and over from October 2002 to March 2003 in Taiwan. This study analyzed the utilization of TCM outpatient services, including admission to the hospital and clinic visits. Results A total of 26 755 participants completed the survey in the six-month period. The data revealed that 10.4% of participants had utilized TCM services in the past one month while 4.2% of participants utilized TCM only (without using Western medicine outpatient services (WM) or Folk therapy (F'I')). The average visits of TCM services per patient was higher among people who had utilized TCM and FT services (2.68 visits) than among those who had utilized WM and FT services (2.15 visits) or TCM services alone (2.15 visits) during the previous one month. Younger people (odds ratio OR= 1.78, 95%C/= 1.47-2.16), women (compared with men), and people with higher education levels (OR = 1.58, 95%CI =1.25-1.98) were more likely to visit TCM than compared groups. People with self-reported poor health status (OR = 2.07,95%CI = 1.76-2.44) and people who exercise regularly (OR = 1.17, 95%CI = 1.07-1.27) had higher ORs to visit TCM service than comparison group.Conclusions There is a high utilization of TCM in Taiwan. Further studies are needed to investigate the related factors and determinants between the utilization of TCM and the utilization of FT in Taiwan.  相似文献   
140.
Lactate dehydrogenase (LDH, EC 1.1.1.27) catalyzes an exchange reaction between pyruvate and lactate. It is demonstrated here that this reaction is sufficiently fast to cause a significant magnetization (saturation) transfer effect when the 13C resonance of pyruvate is saturated by a continuous-wave (CW) RF pulse. Infusion of [2-(13)C]glucose was used to allow labeling of pyruvate C2 at 207.9 ppm to determine the pseudo first-order rate constant of the unidirectional lactate-->pyruvate flux in vivo. During systemic administration of GABAA receptor antagonist bicuculline, this pseudo first-order rate constant was determined to be 0.08+/-0.01 s-1 (mean+/-SD, N=4) in halothane-anesthetized adult rat brains. In 9L and C6 rat glioma models, the 13C saturation transfer effect of the LDH reaction was also detected in vivo. Our results demonstrate that the 13C magnetization transfer effect of the LDH reaction may be useful as a novel marker for utilizing noninvasive in vivo MRS to study many physiological and pathological conditions, such as cancer.  相似文献   
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