低剂量对比剂MSCT脑动脉成像的可行性及临床应用

目的探讨低剂量对比剂16层螺旋CT脑动脉成像的可行性及临床应用。方法152例MSCTA病例,行Test-Bolus测试确定脑动脉延时扫描时间,再按46ml低剂量对比剂(优维显370mgI/ml)+40ml生理盐水注射行CT扫描,评价CTA图像质量以及临床应用价值。图像评价由显示动脉分支的级数不同按3分制评分。结果脑动脉最大强化均值485.53±83.78(HU),CTA图像质量评分:3分144例(94.7%),2分7例(4.6%),1分1例(0.7%),共发现动脉瘤19例动静脉畸形12例,烟雾病1例,动脉狭窄37例。结论16层螺旋CT低剂量对比剂脑动脉成像图像质量高,能降低对比剂毒性,具有较高的临床实用价值。     

1，25（OH）2D3对脂多糖作用下大鼠腹膜间皮细胞维生素D受体及肿瘤坏死因子α、转化生长因子β1表达的影响

目的 研究脂多糖（LPS）对大鼠腹膜间皮细胞（RPMC）维生素D受体(VDR)及肿瘤坏死因子α（TNF-α）、转化生长因子β1（TGF-β1）表达的影响,从而为1,25（OH）2D3在腹膜透析相关腹膜炎中的应用提供理论依据。 方法 胰蛋白酶消化法原代培养腹膜间皮细胞、传代、经鉴定后分组：(1)正常对照组;(2)脂多糖组：不同浓度的脂多糖（1、10、100 mg/L）分别作用6 h;10 mg/L脂多糖分别作用2、6、12 h;(3)1,25（OH）2D3作用组：10 mg/L脂多糖预孵育2 h后,加1,25（OH）2D3(10－8 mol/L、10－7 mol/L、10－6 mol/L)再作用6 h。RT-PCR法检测VDR mRNA的表达;Western印迹法检测VDR蛋白表达;ELISA法检测上清液TNF-α、TGF-β1的表达。 结果 与对照组相比,LPS组RPMC VDR mRNA和蛋白表达均显著下调（均P < 0.05）。与LPS组相比,1,25（OH）2D3组VDR mRNA和蛋白表达均显著上调（均P < 0.01）。LPS组上清液中TNF-α、TGF-β1浓度均显著高于对照组（均P < 0.01）;1,25（OH）2D3组上清液中TNF-α、TGF-β1浓度均显著低于LPS组（均P < 0.01）。 结论 LPS能下调RPMC VDR mRNA和蛋白的表达,上调TNF-α、TGF-β1表达。1,25（OH）2D3可逆转LPS的作用,上调RPMC VDR mRNA和蛋白的表达,并下调TNF-α、TGF-β1表达。VDR对腹膜透析相关腹膜炎具有一定的保护作用,并具有抑制腹膜纤维化的作用。     

Phase II study of calcitriol-enhanced docetaxel in patients with previously untreated metastatic or locally advanced pancreatic cancer

Summary   Purpose: To determine the safety and efficacy of weekly high-dose oral calcitriol and docetaxel, given to patients with non-resectable, incurable pancreatic cancer. Patients and Methods: Twenty-five patients were enrolled onto this phase II study. Patients were treated with oral calcitriol 0.5 μg/kg on day 1, followed by docetaxel 36 mg/m² IV on day 2, administered weekly for three consecutive weeks, followed by 1 week without treatment. Patients followed a low-calcium diet and increased their hydration. The primary end-point of the trial was time-to-progression. Results: Three of 25 patients attained a partial response (12%, 95% CI 3 to 31) and seven (28%) achieved stable disease. Median time-to-progression was 15 weeks, and median overall survival was 24 weeks. Toxicities observed (hyperglycemia, fatigue) were mostly attributable to the docetaxel or its pre-treatment. Conclusions: This regimen of high-dose calcitriol with docetaxel may have activity in incurable pancreatic cancer, with a modest increase in TTP when compared to historical findings using single-agent docetaxel. However, results do not appear superior to those seen with gemcitabine, with or without erlotinib.     

四川峨眉山地区二叠系与三叠系界线微量元素地球化学研究

通过对峨眉山地区地层剖面的实地观察和测量,采集界线附近的粘土岩,分析了该区微量元素地球化学的组成特征,并通过对稀土元素标准化图解和其它微量元素的研究,利用微量元素的示踪作用以及微量元素地球化学异常,初步探讨了界线粘土岩的来源,为全球二叠—三叠界线研究工作提供依据。     

Responses to a Modified Visual Cliff by Pre-Walking Infants Born Preterm and at Term

ABSTRACT

The purpose of this study was to examine, using a modified visual cliff apparatus, possible perceptual differences at crawling age between infants born preterm and infants born at term without documented visual or motor impairments. Sixteen infants born at term and 16 born preterm were encouraged to crawl to their caregivers on a modified visual cliff. Successful trials, crossing time, duration of visual attention, duration of tactile exploration, motor strategies, and avoidance behaviors were analyzed. A significant surface effect was found, with longer crossing times and longer durations of visual attention and tactile exploration in the condition with the visual appearance of a deep cliff. Although the two groups of infants did not differ on any of the timed measures, infants born at term demonstrated a larger number of motor strategies and avoidance behaviors by simple tally. This study indicates that infants born at term and those born preterm can perceive a visual cliff and adapt their responses accordingly.     

Effects of Oxytetracycline on Mineralization of Bone in Young Rats

The metabolism of minerals and collagen in young rats receiving oxy—tetracycline was studied by employing double—isotope techniques. the dosage of the antibiotic was adjusted to obtain plasma concentrations comparable with human therapeutic levels. Reduced mineralization and possibly increased resorption of bone were observed after oxy tetracycline administration, whereas no effect on the rate of collagen synthesis could be detected.     

Effect of combined treatment with perindoprilat and low-power red light laser irradiation on human erythrocyte membrane fluidity,membrane potential and acetylcholinesterase activity

Erythrocyte membrane fluidity, membrane potential and acetylcholinesterase activity were estimated after in vitro combined treatment of human erythrocytes with perindoprilat and low-power red light irradiation. Membrane fluidity was determined using fluorescent labels spectroscopy; membrane potential was evaluated by means of potential-sensitive fluorescent dyes; and acetylcholinesterase activity was estimated using the Ellman method. Both perindoprilat and laser irradiation, when used separately, increase microviscosity in the polar region and hyperpolarize the membranes in comparison with control erythrocytes. The combined action of these agents does not cause any further change in these parameters. Perindoprilat has an additional inhibitory effect on the activity of acetylcholinesterase, whereas laser irradiation causes an increase in the activity of the enzyme. Their combined action restores the initial activity of the enzyme independently of the sequence of treatment with both agents.     

抗病毒药物2,5,6-三取代-4(3H)嘧啶酮衍生物的合成及诱导干扰素活性

In order to search for more ideal antiviral drugs,21 substituted pyriiT1idinone derivatives were designed and synthesized,among which 11 were not reported before. The cheinicalstructures were characterized by elemen tal and spectral analysis. The serum interferon - inducing activity was tested in mice. All 2-amino-5-bromo-6-substituted-4-(3H)pyrimidinone compounds were shown to have interferon inducing activity.The corresponding substituted pyrimidine thiones were less active.The new compounds of 6-sulfophenyl derivatives are soluble in、water, but the interferon-inducing activity are not higher than the original compound of ABPP.