产科诊断剂量超声波对培养细胞影响的实验研究

采用模拟在人体中使用的实测超声剂量，对体外培养的Ｌ－９２９株细胞进行辐照，通过细胞回复能力试验，观察回复前后的细胞增殖与抑制。对体外培养的人胚肺纤维细胞经１次及５次辐照，观察了ＤＮＡ及细胞核面积的影响。并通过电镜观察了细胞超微结构的变化。上述实验结果，均提示经辐照后细胞有增殖趋向     

铁缺乏时淋巴细胞增殖反应改变的实验研究

本研究采用体外细胞培养，３Ｈ－Ｔｄｒ掺入，原子吸收光谱分析等技术方法，观察了低浓度Ｆｅ－ｃｉｔ时淋巴细胞内铁浓度变化及经ＣｏｎＡ、ＰＨＡ诱导的细胞增殖反应能力改变，结果显示：铁缺乏时（第２、３、４组）ＳＩ降低，与正常组（第１组）比较相差非常显著（Ｐ＜０．０１），ＳＩ与细胞内铁浓度的变化呈显著正相关（Ｐ＜０．０５，ｒ１＝０．９４６６，ｒ２＝０．９３３９），说明铁缺乏时淋巴细胞增殖反应能力受抑。     

Distribution of glutathione and glutathione-related enzyme systems in mitochondria and cytosol of cultured cerebellar astrocytes and granule cells

The cellular and regional distribution of glutathione (GSH) and GSH-related enzyme systems involved in cellular defense against reactive oxygen species and electrophilic xenobiotics in the nervous system has been extensively studied. However, little is known about the subcellular distribution of GSH systems in brain tissue and cultured neural cells. The present study investigates the distribution of mitochondrial and cytosolic GSH and GSH-related enzymes in cultured cerebellar astrocytes and granule cells, and compares them with levels in the adult rat cerebellum. Cytosolic GSH levels and cytosolic activities of glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) in astrocytes were 57, 153, 245, and 92% higher than those found in granule cells, respectively. In contrast, granule cells contained significantly higher mitochondrial GSH levels than astrocytes. Granule cells also demonstrated comparable mitochondria/cytosolic concentrations of GSH and GR, GPX and GST activities to those observed in the cerebellar tissue, whereas ratios in astrocytes were markedly lower. Although in vitro treatments with 100 μM ethacrynic acid depleted both cytosolic and mitochondrial GSH in cultured astrocytes and granule cells in a time-dependent fashion, cellular GSH in granule cells was more resistant to the GSH-depleting agent than astrocytes. These results suggest that although GSH and GSH-related enzymes are abundant in cytosolic compartments of astrocytes, mitochondrial pools are relatively small. Since brain mitochondria are sites of significant hydrogen peroxide generation, the mitochondrial localization of GSH and its associated enzymes in neural cells provide important defenses against toxic oxygen species in the nervous system. Differences in subcellular distribution of GSH systems in individual neural cell types may provide a basis for selective cellular and/or subcellular expression of neurotoxicity.     

Image technique optimization in MR imaging of a titanium alloy joint prosthesis

The purpose of this study was to explore systematically the effect of the imaging parameters changeable by the user in spin-echo (SE) imaging sequences to minimize image distortion when imaging joint prostheses. A titanium alloy hip joint prosthesis was studied at 1.0 T. The SE imaging parameters were bandwidth/pixel (BW/p), TE, strength of encoding gradients (matrix size), echo train length (ETL), and direction of phase and frequency encoding. The effect of ETL in rapid acquisition relaxation enhanced (RARE) sequences was also evaluated with a turbo-SE sequence using a different ETL with the same TR and an effective TE. It is concluded that an optimized image quality can be achieved in SE imaging by using a high bandwidth/pixel value (at least 130 Hz/pixel), a high resolution matrix (256–512), sequences with multiple refocusing, and a frequency-encoding axis parallel to the long axis of the prosthesis. The degree of distortion is reduced with this optimized technique.     

Regeneration of kidney tubular epithelial cells

Conclusion The mechanisms that regulate regeneration of kidney epithelial cells after acute tubular necrosis are poorly understood. Repair of the nephron can take place in the adverse systemic metabolic setting caused by failure of renal function. This clinical observation suggests that factors released at the site of the tubular insult can mediate repair. Studies carried out in this and other laboratories show that kidney epithelial cells can release and respond to polypeptide growth factors which may thereby contribute to renal regeneration by autocrine and paracrine mechanisms. Specific growth factors secreted by cells and deposited in the tubular basement membrane prior to injury may subsequently participate in nephron repair. In addition, adenine nucleotides released from injured or dying cells at the injury site or provided exogenously could stimulate surviving renal epithelial cells at the edges of the wound to migrate along the basement membrane to rapidly reepithelialize the nephron and subsequently initiate mitogenesis to replace cells lost by necrosis.The nephrotoxic effect of many agents used in cancer chemotherapy and the older age of patients undergoing complicated surgical procedures has increased the incidence of ARF, whereas the mortality rate has not changed since the early 1950s [22]. Thus there is considerable need for innovative therapeutic strategies. An important goal of future research efforts is to identify new growth factors that facilitate migration, differentiation, and proliferation of renal epithelial cells at sites of tubular necrosis. Isolation and use of these agents in combination with dialysis and nutritional support could speed renal regeneration and thereby improve the outcome in patients with this condition.Abbreviations ARF acute renal failure - ECM extracellular matrix - EGF epidermal growth factor - FGF fibroblast growth factor - IGF insulin-like growth factor - MGSA melanocyte growth-stimulating activity - PDGF platelet-derived growth factor - IGF transforming growth factor     

二甲亚砜对人表皮的核酸和蛋白质合成的影响

用体外培养的人的伪表皮作为模型，进行药物毒理学作用的研究，观察了二甲亚砜（ＤＭＳＯ）在不同浓度和不同接触时间条件下，对人的伪表皮细胞脱氧核糖核酸（ＤＮＡ）、核糖核酸（ＲＮＡ）和蛋白质合成的影响：随着接触时间的延长，ＤＮＡ、ＲＮＡ和蛋白质合成均受抑制。低浓度条件下（１％），ＤＮＡ、ＲＮＡ和蛋白质合成增加；在１５～５０％浓度下，ＤＮＡ和蛋白质合成抑制，而ＲＮＡ合成仍增加；在高浓度条件下（７０％～１００％），ＤＮＡ、ＲＮＡ和蛋白质合成均明显抑制。     

乳必泰胶囊药效学研究

目的：探讨乳必泰胶囊的药效学。方法：通过大鼠乳腺增生模型及其它试验观察本品对乳腺增生的抑制作用及其它药理作用。结果：乳必泰胶囊能明显抑制乳腺组织增生，降低血清雌二醇水平，减少乳头直径及子宫系数，能明显抑制角叉菜胶引起的足肿胀。结论：这些作用说明乳必泰胶囊用于治疗乳腺增生，可能对患的症状有一定缓解作用。     

Isolation and identification of chondroitin sulfates from the mud snail

Chondroitin sulfates were isolated from the mud snail. For the quantitative analysis of enzymatic digestion products of isolated chondroitin sulfates, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitinase ABC, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-D-galactose (ΔDi-OS), 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-6-O-sulfo-D-galactose (ΔDi-6S) and 2-acetamide-2-deoxy-3-O-(β-D-gluco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose (ΔDi-4S) were produced from the mud snail chondroitin sulfates. The analysis showed that relative proportion of ΔDi-OS/ΔDi-6S/ΔDi-4S was 58.7/3.1/38.2. The immunomodulating activity of chondroitin sulfate was examined by cell proliferation assay and these results suggest that it might be a immunosuppressant.     

树突状细胞的移行与递呈抗原作用的实验研究

借助异硫氰酸荧光素（ＦＩＴＣ）的可显示性，将其作为抗原免疫ＣＢＡ小鼠，以观察树突状细胞的移行及其抗原递呈方式与功能。结果表明，经ＦＩＴＣ两次刺激后（皮内），移行至局部淋巴结的树突状细胞数明显高于对照组（Ｐ＜０．０５）。ＦＡＣＳ的分析结果亦表明，局部淋巴结内的树突状细胞荧光阳性率显著增高，且荧光显微镜观察呈现不均一的膜荧光，提示该细胞的抗原递呈方式为单纯膜结合型，而无内在化过程。ＣｏｎＡ刺激的淋巴细胞增殖反应及ＦＩＴＣ特异性刺激的细胞增殖反应则分别体现了树突状细胞抗原递呈作用的后效应。