外来入侵物种造成的间接经济损失估算模型

外来入侵物种已对我国生态系统功能造成严重破坏.由于没有市场交易和市场价格,采用机会成本、影子价格或影子工程费用估算外来入侵物种对生态系统服务功能造成的经济损失.在分析森林、农田、草原、湿地、草坪等生态系统服务功能价值评估的基础上,根据外来入侵物种对各类生态系统服务功能造成的损害程度,分别建立了外来入侵物种对森林、农田、草原、湿地、草坪等生态系统的间接经济损失评估模型;并在参数估计的基础上,计算了2000年外来入侵物种造成的间接经济损失.     

肿瘤标志物联合检测在原发性肝细胞癌早期诊断中的应用

用生物发光免疫分析法、 比色法联合检测确诊的原发性肝细胞癌（53例）、 乙型病毒 性肝炎（80例）、 慢性乙肝合并肝硬化（34例）患者同份血清的肿瘤标志物甲种胎儿蛋白( AFP)和肿瘤特异性生长因子(TSGF)．　结果显示, 原发性肝细胞癌组血清TSGF和AFP与其他 组比较均有显著差异（P<0.01）; 原发性肝癌组中TSGF与AFP联合阳性检出率为96.2 %． 关键词: 生物发光免疫分析技术; 甲种胎儿蛋白; 肿瘤特异性生长因子; 原发性肝细胞癌     

The role of P-glycoprotein/cellular prion protein interaction in multidrug-resistant breast cancer cells treated with paclitaxel

We previously reported that treatment with P-glycoprotein (P-gp) substrates promotes in vitro invasion in multidrug-resistant (MDR) breast cancer cells. This effect is initiated by the P-gp pump function and mediated by interaction of P-gp with some unknown component(s). However, the underlying mechanism(s) remains poorly understood. Here we confirm a novel physical interaction between P-gp and cellular prion protein (PrP^c). Blocking P-gp activity or depletion of PrP^c inhibited paclitaxel (P-gp substrate)- induced invasion. Paclitaxel further facilitated the formation of P-gp/PrP^c clusters residing in caveolar domains and promoted the association of P-gp with caveolin-1. Both caveolin-1 and the integrity of caveolae were required for the drug-induced invasion. In addition, the P-gp/PrP^c complex also played an important role in anti-apoptotic activity of MCF7/Adr cells.These data provide new insights into the mode by which MDR breast cancers evade cytotoxic attacks from P-gp substrates and also suggest a role for P-gp/ PrP^c interaction in this process. Received 4 September 2008; received after revision 16 November 2008; accepted 18 November 2008     

Notch and cancer: a double-edged sword

The highly conserved Notch signaling pathway plays pleiotropic roles during embryonic development and is important for the regulation of selfrenewing tissues. The physiological functions of this signaling cascade range from stem cell maintenance and influencing cell fate decisions of barely differentiated progenitor cells, to the induction of terminal differentiation processes, all of which have been found to be recapitulated in different forms of cancers. Although Notch signaling has mostly been associated with oncogenic and growth-promoting roles, depending on the tissue type it can also function as a tumor suppressor. Here we describe recent findings on Notch signaling in cancer and tumor angiogenesis, and highlight some of the therapeutic approaches that are currently being developed to interfere with tumor growth and progression. Received 2 April 2007; received after revision 29 June 2007; accepted 2 July 2007     

Molecular targets of glioma invasion

Glioblastoma multiforme is the most common and lethal primary malignant brain tumor. Although considerable progress has been made in technical proficiencies of surgical and radiation treatment for brain tumor patients, the impact of these advances on clinical outcome has been disappointing, with median survival time not exceeding 15 months. Over the last 30 years, no significant increase in survival of patients suffering from this disease has been achieved. A fundamental source of the management challenge presented in glioma patients is the insidious propensity of tumor invasion into distant brain tissue. Invasive tumor cells escape surgical removal and geographically dodge lethal radiation exposure and chemotherapy. Recent improved understanding of biochemical and molecular determinants of glioma cell invasion provide valuable insight into the underlying biological features of the disease, as well as illuminating possible new therapeutic targets. These findings are moving forward to translational research and clinical trials as novel antiglioma therapies. Received 25 July 2006; received after revision 27 October 2006; accepted 22 November 2006     

肿瘤标志物的最新研究技术及其临床检测方法

肿瘤标志物已被广泛应用于肿瘤的临床诊断、分期、监测疗效和预后等方面.通过对肿瘤标志物的研究技术和临床检测方法进行详细介绍,可提高分子诊断及应用临床联合检测技术,能帮助肿瘤患者早期确诊和有效治疗.     

A new cell line (XTY) from a tumor ofXenopus laevis

A new cell line (XTY) was derived from a tumor of a femaleXenopus laevis. This cell line has been proliferating in standard amphibian culture medium for more than 4 years (470 generations) and has a doubling time of 75.5 h at 25°C. The cells aggregate into large groups, and their stellate morphology and the expression of desmin demonstrated by immunocytochemistry suggest that their origin is not epithelial.     

Agglutinins from aquatic insects—tumor cell agglutination activity

Agglutinins were identified in whole body extracts of aquatic insects by means of murine tumor cell agglutination, using sarcoma 180 ascites, Ehrlich, and MM-46 cells. Screening revealed agglutinins in 5 of 10 of the larvae tested, and in 2 of 6 of the water-dwelling adult insects;Gerris paludum insularis andGyrinus japonicus. Only the agglutinin from adultG. paludum also agglutinated human erythrocytes. An ascites tumor was converted into a solid form in vivo after administration ofG. paludum agglutinin. The observation that these aquatic insect agglutinins preferentially agglutinate tumor cells has considerable implications in terms of anti-tumor effects such as inhibition of cell proliferation and metastasis.Deceased.     

生长/分化因子MK家族的生物学作用的研究进展

孕中期肾蛋白（Ｍｉｄｋｉｎｅ，ＭＫ）和多效生长因子（Ｐｌｅｉｏｔｒｏｐｈｉｎ，ＰＴＮ）组成一种新的肝素结合生长／分化因子家族。它们都是分泌性单肽链蛋白，蛋白质结构都类似。ＭＫ和ＰＴＮ基因均可在胚胎发育期在多种组织大量表达，而仅ＰＴＮ在出生后，有一种神经系统的短暂表达高峰，两者不同地见于数种成年期组织。这些发现结合体外实验结果，提示它们在发育上有重要的促生长／分化作用，并具有神经营养活性，在成年期也有某些未知的生理功能。其中，尤以对神经系统的发育和维持最为重要。它们还可促进血管内皮细胞的纤溶活性，并可能作为肿瘤生长因子在某些肿瘤的发生中起作用