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雾化吸入羟基喜树碱在兔体内的组织分布   总被引:4,自引:0,他引:4  
目的研究雾化吸入羟基喜树碱在兔体内的组织分布特点。方法建立了采用RP-HPLC法测定兔血浆和组织中羟基喜树碱浓度的方法。比较雾化吸入和静脉注射给药后的组织分布特点与血药浓度。结果相对于静脉注射途径,采用雾化吸入途径给予同剂量羟基喜树碱后0.5,1和2 h肺中的药物浓度分别提高了13.52,27.81和20.82倍,而药物在其他组织中的分布几乎都显著降低。雾化吸入给药后的绝对生物利用度为7.38%。结论雾化吸入给予羟基喜树碱能够在维持肺内药物高浓度的同时显著降低药物在其他正常组织以及血浆中的分布。羟基喜树碱改用雾化吸入途径给药治疗肺癌具有明显的优势。  相似文献   
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目的探讨我国京剧艺术不同行当的电声门图和声测试的参数特点。方法采用电脑多媒体操作系统,使用Dr.Speech3.0软件,对137名20~64岁不同行当的专业演员发稳态元音屈/ae、/a:/、i:/同步进行声门图和声学测试的检测和分析,并以嗓音健康的普通人群作对照组。结果京剧艺术各行当元音/ae/、/a:/、/i:/声门图和声学测试除Fo差异比较显著外,其他声门图参数Fo、Jitter、Shimmer、NEE、CQ、CQP及声学测试参数Fo、Jitter、Shimmer、NEE均有其不同的参数值,有统计学意义(P〉0.01、P〉0.05)。对照组的各嗓音参数值均在DPSS提供的正常范围内。结论京剧各行当的嗓音有其独特的声学特征,引用Dr.Speech3.0软件可对各行当嗓音参数值进行临床客观检测与评估,对京剧嗓音的训练与保健提供了有益的临床价值。  相似文献   
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The extent of peritoneal metastases (PM) largely determines the possibility of complete or optimal cytoreductive surgery in advanced ovarian cancer. An objective scoring system to quantify the extent of PM can help clinicians to decide whether or not to embark on CRS. Therefore several scoring systems have been developed by different research teams and this review summarizes their performance in predicting a complete or optimal cytoreduction in patients with advanced ovarian cancer. A systematic search in the MEDLINE database revealed 19 articles that described a total of five main scoring systems to predict the completeness of CRS in patients with FIGO stage III-IV ovarian cancer based on the surgical exploration of the abdominal cavity; PCI, PIV, Eisenkop, Espada, and Kasper. The Peritoneal Cancer Index (PCI) and the Predictive Index Value (PIV) were mentioned most frequently and showed AUCs of 0.69–0.92 and 0.66–0.98, respectively. Due to the use of different cut-offs sensitivities and specificities greatly varied. Therefore with the current data, no scoring system could be identified as best. An objective measure of the extent of disease can be of great clinical use for identifying ovarian cancer patients for which a complete (or optimal) CRS is achievable, however due to local differences in treatment strategies and surgical policy a widely adopted objective scoring system with a standard cut-off value is not feasible. Nevertheless, objective scoring systems can play an important role to guide treatment decisions.  相似文献   
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Adoptive transfer of regulatory T (Treg) cells have been employed effectively for suppression of several animal models for autoimmune diseases. In order to employ Treg cell therapy in patients, it is necessary to generate Treg cells from the patient's own cells (autologous) that would be able to suppress effectively the disease in vivo, upon their reintroduction to the patient. Towards this objective, we report in the present study on a protocol for a successful immune-regulation of experimental autoimmune myasthenia gravis (EAMG) by ex vivo – generated autologous Treg cells. For this protocol bone marrow (BM) cells, are first cultured in the presence of GM-CSF, giving rise to a population of CD11c+MHCII+CD45RA+CD8 DCs (BMDCs). Splenic CD4+ T cells are then co-cultured with the differentiated BM cells and expand to 90% of Foxp3+ Treg cells. In vitro assay exhibits a similar dose dependent manner in the suppression of T effector cells proliferation between Treg cells obtained from either healthy or sick donors. In addition, both Treg cells inhibit similarly the secretion of IFN-γ from activated splenocytes. Administration of 1 × 106 ex-vivo generated Treg cells, I.V, to EAMG rats, modulates the disease following a single treatment, given 3 days or 3 weeks after disease induction. Similar disease inhibition was achieved when CD4 cells were taken from either healthy or sick donors. The disease suppression was accompanied by reduced levels of total AChR specific antibodies in the serum. Moreover, due to the polyclonality of the described Treg cell, we have examined whether this treatment approach could be also employed for the treatment of other autoimmune diseases involving Treg cells. Indeed, we demonstrated that the ex-vivo generated autologous Treg cells suppress Adjuvant Arthritis (AA) in rats.This study opens the way for the application of induced autologous Treg cell therapy for myasthenia gravis, as well as for other human autoimmune diseases involving Treg cells.  相似文献   
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The performance of enzyme linked immunosorbent assays (EAST) for identifying six indoor allergens was evaluated using skin prick test (SPT) as reference tests in 154 children with allergic rhinitis. Sensitivity of EAST ranged from 9% (cat) to 54% (HDM) with specificity of 74%(cockroach) to 100% (cat) with an agreement ranged from 58 to 86%. Cut off values ?> ?0.35 kU/L showed best sensitivity and specificity. Our findings agree with extant literature which suggests that the ability of EAST to determine the precipitating allergen is moderate. Assays for definitively identifying the inhalant allergen are currently not available.  相似文献   
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