TNF与急性早幼粒细胞白血病

１６例急性早幼粒细胞白自病患者血清ＴＮＦ活性明显高于正常对照（Ｐ＜０．０５），而经ＲＡ诱导分化治疗中期及治疗后明显降低（Ｐ＜０．０５），但仍高于正常对照组。各治疗时相的外周白细胞浆内ＴＮＦ平均水平及正常对照间均无明显差别（Ｐ＞０．０５），治疗前及治疗中期胞浆ＴＮＦ活性升高率明显高于治疗后或正常对照（Ｐ＜０．０５）。相关分析表明：血清ＴＮＦ活性水平与外周血ＷＢＣ总数或骨髓ＧＭ－ＣＦＵ无明显相关，而与     

Facilitating visuospatial attention for the contralateral hemifield by repetitive TMS on the posterior parietal cortex

Previous studies have demonstrated that repetitive transcranial magnetic stimulation (rTMS) could modulate the visuospatial functions. In this study, we investigated the effect of off-line high frequency subthreshold rTMS, when applied over the right or left posterior parietal cortex (PPC), on the visuospatial attention of the bilateral hemispaces. The subjects underwent visuospatial tasks before and immediately after receiving 1000 pulses of 10 Hz rTMS for a period of 20 min, and their responses were recorded. Our results demonstrated that the high frequency rTMS applied over the PPC produced facilitative effects on the visuospatial attention to the contralateral hemispace. The inhibitory effect to the ipsilateral hemispace was noticeable only in the left PPC.     

卫生资源优化配置的伦理要求

1　医学目的和卫生资源的配置卫生资源的配置问题 ,不是一个孤立的问题 ,它是同一定的医学目的联系在一起的 ,一定的医学目的 ,对卫生资源的配置起着导向作用 ,是为一定的医学目的服务的。传统医学由于受科学技术和社会发展的局限 ,以及受传统疾病模式的影响 ,只能把医学的目的定位于对疾病的治疗上 ,向一个消防队员一样 ,哪里有火、火大 ,就把目标投向哪里 ,从而终日疲于奔命 ,和这种医学目的相适应 ,这时的卫生资源配置就只能是把大部分卫生资源用于对疾病的诊治上。随着社会的发展 ,疾病模式发生了显著的变化 ,这种救火式的医疗 ,致使一…     

Metabolism of saikosaponin c and naringin by human intestinal bacteria

By human intestinal bacteria, saikosaponin c was transformed to four metabolites, prosaikogenin E1 (E1) prosaikogenin E2 (E2), prosaikogenin E3 (E3) and saikogenin E. Metabolic time course of saikosaponin c was as follows; in early time, saikosaponin c was converted to E1 and E2, and then these were transformed to saikogenin E via E3. Also, this metabolic pathway was similar to the metabolism of saikosaponin c by rat intestinal bacteria.Bacteroides JY-6 andBacteroides YK-4, the bacteria isolated from human intestinal bacteria, could transform saiko-saponin c to E via E1 (or E2) and E3. However, these bacteria were not able to directly transform E1 and E2 to saikogenin E. Naringin was mainly transformed to naringenin by human intestinal bacteria. The minor metabolic pathway transformed naringin to naringenin via prunin. By JY-6 or YK-4, naringin was metabolized to naringenin only via prunin.     

Hydrolysis kinetics of metampicillin by high performance liquid chromatography

The hydrolysis of metampicillin to ampicillin was investigated using high performance liquid chromatography. We developed the simultaneous determination of metampicillin and ampicillin using a Zorbax CN column and 5% acetonitrile and 8% methanol in 0.02 M phosphate buffer (pH 7.0) as mobile phase. Metampicillin was hydrolyzed to ampicillin with half life of 41.5 min at physiological pH and temperature. In acidic pH, metampicillin was rapidly hydrolyzed to ampicillin within a chromatographic separation.     

Biological monitoring of tetrahydrofuran: contribution of a physiologically based pharmacokinetic model

A seven-compartment physiologically based pharmacokinetic (PBPK) model was developed to predict biological levels of tetrahydrofuran under various exposure scenarios. Affinities for the tissue were estimated from measurements of liquid-gas partition coefficients for water, olive oil, and blood. Metabolism was assumed to follow a rapid first order reaction. urinary excretion was simulated considering passive reabsorption of tetrahydrofuran in the tubules. The validity of the model was tested by comparison with available experimental and field data. Agreement was satisfactory with all studies available except one, which showed much higher results than expected. The source of this difference could not be identified, but cannot be explained by different exposure conditions, such as duration, concentration, or physical work load. However, it is recommended that this particular study not be used in the establishment of a biological exposure index. Simulation of repeated occupational exposure with the PBPK model allowed the prediction of biological levels that would be reached after repeated exposure at the American Conference of Governmental Industrial Hygienists' threshold limit value, time-weighted average of 200 ppm. For samples taken at the end of the shift, the PBPK model predicts 5.1 ppm for breath, 57 mumol/L (4.1 mg/L) for venous blood, and 100 mumol/L (7.2 mg/L) for urine.     

Immunohistochemical analysis of Fas ligand expression in normal human tissues

Cross-linking of Fas and Fas ligand (FasL) induces apoptosis in Fas-bearing cells and regulates apoptosis. Fas is widely expressed in normal human tissues, but FasL expression has been considered to be restricted to lymphoid tissues. Recent studies have demonstrated that FasL is also expressed in some nonlymphoid tissues. To screen the in situ expression of FasL in normal human tissues, immunohistochemistry was performed using paraffin-embedded human tissues. FasL immunostaining was easily detected in testis, neurons, trophoblasts, tonsil, lymph node, Paneth cells, hepatocytes, renal tubular epithelium and bronchial epithelium, consistent with previous reports. Surprisingly, FasL was also expressed in many other cell types, including thymic medulla, skeletal muscle, cardiac muscle, pituitary gland, parathyroid gland, prostate glands, oocytes, epithelium of fallopian tube, endometrial glands, and gastric parietal cells. These findings demonstrate that FasL is widely expressed in human tissues and suggest that wide but cell-type specific expression of FasL may not only be implicated in the regulation of immune homeostasis but also in the regulation of cell death and life in many cell types in vivo.     

MR microcirculation assessment in cervical cancer: correlations with histomorphological tumor markers and clinical outcome.

This article reviews the experience available to date on microcirculation assessment in cancer of the cervix including correlation studies of magnetic resonance (MR) microcirculatory parameters with histo-morphometric predictors and direct correlation with patient outcome. The data suggest that MR microcirculation parameters do not always correlate with histo-morphometric parameters, while there is evidence that MR parameters predict patients' treatment outcome. These observations raise the issue that perhaps the histo-morphometric parameters, accepted gold standards for tumor angiogenesis and prognostic factors, reflect anatomical information at a "static" single time point and may not always provide sufficient information on the "dynamic" microcirculation function of the tumor. MR microcirculation assessment reflects both anatomical and functional information and may provide this additional information on the "dynamic" angiogenic and metabolic status of a tumor. Therefore, assessment of tumor microcirculation may augment the individual risk profile in cervical cancer patients and has the potential to impact on therapy selection and treatment outcome.