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张旭东  郭树忠 《医学争鸣》2005,26(18):1716-1718
CTLA4-Ig是一种融合免疫球蛋白,可以选择性地阻断CD28与B7的信号传导通路,导致T细胞免疫失能,诱导对特异性抗原的免疫耐受. 本文介绍了其生物学特性、免疫诱导耐受机制及在异体移植方面的研究进展和局限性,其在异体移植方面展示了良好的应用前景.  相似文献   
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Xanthogranulomatous orchitis is an extremely rare inflammatory non-neoplastic destructive lesion of the testis. We report a 44-year-old man who presented with right scrotal swelling and two discharging sinuses. Testicular tumor markers were normal. Scrotal ultrasound showed heterogeneous testicular areas and irregular margin of the tunica. Surgical exploration revealed infected, unhealthy testicular tissue with necrosis and tumor-like lesion. Orchidectomy was done and histopathology showed xanthogranulomatous orchitis.  相似文献   
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Tumours of the nerve sheath origin in the head and neck are not common. Schwannomas are rare. Only a few cases have been reported so far. We report a rare case of Schwannoma of Submandibular region arising from the lingual nerve.  相似文献   
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反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量   总被引:7,自引:0,他引:7  
倪坤仪  王建  陈健  郁建  屠树滋 《药学学报》1994,29(8):624-633
反相高效液相色谱法测定牛黄类中成药中胆汁酸的含量倪坤仪,王建,陈健,郁建,屠树滋(中国药科大学210009)含牛黄的中成药种类很多,在医疗中具有广泛的用途。中药牛黄中主要成分为胆汁酸和胆红素。本文主要研究用HPLC法测定牛黄以及含牛黄中成药中胆汁酸的...  相似文献   
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Lipophilic diaminocyclohexane (DACH) platinum complexes have shown significant promise in preclinical studies. One of these compounds,cis-bis-neodecanoato-trans-R,R-1,2-diaminocyclohexaneplatinum(II) (NDDP), which contains two branched leaving groups of 10 carbons, showed a favorable toxicity profile in a liposomal formulation in early clinical trials. However, like many other DACH platinum compounds with branched leaving groups, it is unstable within the liposomes, thus preventing its widespread clinical evaluation. We studied the effect of the configuration of leaving groups on intraliposomal complex stability by studying a series of DACH platinum complexes containing linear alkyl carboxylato leaving groups of 5–18 carbons. The entrapment efficiency was greater than 90% for all liposomal preparations of the complexes and was independent of lipid composition and length of the leaving group. The drug leakage from the liposomes was minimal, but was directly related to the length of the leaving group. Intraliposomal stability was inversely related to the length of the leaving group and the content of DMPG (dimyristoyl phosphatidylglycerol) in the liposomes. The effect of length of leaving group on intraliposomal stability was minimal in compounds with leaving groups smaller than 10 carbons, but very pronounced in compounds with longer leaving groups. Stable liposomal formulations of selected compounds with leaving groups of 6 and 10 carbons had significant in vivo antitumor activity against both L1210/S and L1210/PDD leukemias. The results indicate (1) that compounds with linear leaving groups are much more stable within DMPG-containing liposomes than compounds with branched leaving groups and (2) that DMPG is required for in vivo antitumor activity. Stable and active liposomal formulations of selected compounds with linear leaving groups have been identified. These formulations are candidates for clinical development.Abbreviations DMPC dimyristoyl phosphatidylcholine - DMPG dimyristoyl phosphatidylglycerol - L-NDDP liposomalcis-bis-neodecanoato-trans-1,2-diaminocyclohexaneplatinum(II) The work reported in this paper was supported in part by NIH grants CA 41581, 45423, 50270, and 58342  相似文献   
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Low density lipoprotein (LDL) has been found to represent a suitable carrier for cytotoxic drugs that may target them to cancer. This study investigated whether very low density lipoprotein (VLDL), LDL and high density lipoprotein (HDL) can be used to effectively incorporate four cytotoxic drugs, 5-fluorouracil (5-FU), 5-iododeoxyuridine (IUdR), doxorubicin (Dox) and vindesine; characterized the complexes; and examined the effect of incorporation on drug cytotoxicity against HeLa cervical and MCF-7 breast carcinoma cells. Significant drug loading was achieved into all three classes of lipoproteins, consistent with the sizes and hydrophobicity of the drugs. The relative loading efficiency was found to be vindesine>IUdR>Dox>5-FU for all three classes of lipoproteins. As shown by electron microscopy (EM), drug incorporation did not affect the size or morphology of the lipoproteins. Differential scanning calorimetry (DSC) showed that drug loading did not significantly change the thermal transition temperature of core lipids in the lipoproteins. The transition enthalpy was changed only for LDL–Dox and LDL–vindesine. The drugs remained stable in the lipoproteins as determined by high performance liquid chromatography (HPLC). EM, DSC and HPLC data suggest that drugs were incorporated into lipoproteins without disrupting their integrity and drugs remained in their stable forms inside lipoproteins. Compared with free drugs in cytotoxicity assays, the IC50 values of LDL– and HDL–drug complexes were significantly lower (2.4- to 8.6-fold for LDL complexes and 2.5- to 23-fold for HDL complexes). All free or lipoprotein-bound drug formulations were comparably more cytotoxic against MCF-7 than HeLa cells. Upregulating the lipoprotein receptors enhanced, and downregulating them inhibited, the cytotoxicity, indicating the mechanistic involvement of lipoprotein receptor pathways. Complexes of all four drugs with VLDL, in contrast to LDL and HDL, had the same cytotoxicity as the four corresponding free drugs. Our results suggest that further studies are required of the potential of HDL to be a cancer targeting drug carrier.  相似文献   
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