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991.
Human transmissible spongiform encephalopathies (TSE) encompass a group of rare neurodegenerative diseases. In April 2004, a group of international experts and regulators met in Buenos Aires, Argentina, to review the safety and to reach consensus on the use of urinary-derived gonadotrophins with respect to TSE. Iatrogenic transmission of Creutzfeldt-Jakob Disease (CJD) from pituitary-derived gonadotrophins has been reported, no infectivity in urine has been demonstrated, and no definite cases of transmission via urine have been reported. It is currently not possible to monitor donor urine or finished product for the presence of prions. Therefore the assessment of risk has to be based on the likelihood of infection in urine, the source of the urine, and the capacity of the manufacturing process to remove any adventitious infection. Urine for the production of medicinal products should be obtained from sources that minimize the possible presence of materials derived from subjects suffering from human TSE. As no strong evidence for TSE infectivity in urine exists, it can be concluded that the risk of disease-generating prions and TSE infectivity being present in donor urine is low. Current evidence indicates that, with respect to the risk of TSE infection, urinary-derived gonadotrophins appear to be safe. 相似文献
992.
Luby TM Cole G Baker L Kornher JS Ramstedt U Hedley ML 《Clinical immunology (Orlando, Fla.)》2004,112(1):45-53
Injection of microparticle-encapsulated DNA elicits immune responses to plasmid-encoded antigens in mice and humans. Cytochrome P450 CYP1B1 (CYP1B1) is a member of the CYP1 P450 enzyme family that is overexpressed in a variety of solid tumors. The work described herein was performed to study the kinetics of stimulating T cell responsiveness with an encapsulated DNA encoding CYP1B1 and provides support for the clinical development of this formulation. Immunization of HLA-A2/Kb transgenic mice with human CYP1B1 encoding plasmid DNA formulated in poly(lactide-co-glycolide) (PLG) microparticles elicits CD8+ T cells that respond to human CYP1B1-positive target cells. The duration of the immune response, the effect on the immune response of multiple injections, and the safety of repeated injections were studied. These results show that the PLG-encapsulated DNA therapeutic elicits durable immune responses to CYP1B1, the responses are dependent on repeat immunization, and that the formulation is well tolerated. 相似文献
993.
目的:探讨了冠心病患者治疗前后血清SOD、ET及T淋巴细胞亚群水平。方法:分别应用放免法和单克隆抗体法对42例冠心病患者进行了血清SOD、ET及T淋巴细胞亚群水平检测,并与35名正常健康人作比较。结果:冠心病患者在治疗前血清ET水平显著地高于正常人组(P<0.01),而SOD和CD4/CD8比值明显地低于正常人组(P<0.01),经治疗后一个月则与正常人组比较差异无显著性(P>0.05)。结论:检测冠心病患者血清SOD、ET及T淋巴细胞亚群水平对判断病情及其预后均具有一定的临床实用价值。 相似文献
994.
The peroxisome proliferator-activated receptor- (PPAR), first identified in 1990 as a member of the nuclear receptor superfamily, has a central role in the regulation of numerous target genes encoding proteins that modulate fatty acid transport and catabolism. PPAR is the molecular target for the widely prescribed lipid-lowering fibrate drugs and the diverse class of chemicals collectively referred to as peroxisome proliferators. The lipid-lowering function of PPAR occurs across a number of mammalian species, thus demonstrating the essential role of this nuclear receptor in lipid homeostasis. In contrast, prolonged administration of PPAR agonists causes hepatocarcinogenesis, specifically in rats and mice, indicating that PPAR also mediates this effect. There is no strong evidence that the low-affinity fibrate ligands are associated with cancer in humans, but it still remains a possibility that chronic activation with high-affinity ligands could be carcinogenic in humans. It is now established that the species difference between rodents and humans in response to peroxisome proliferators is due in part to PPAR. The cascade of molecular events leading to liver cancer in rodents involves hepatocyte proliferation and oxidative stress, but the PPAR target genes that mediate this response are unknown. This review focuses on the current understanding of the role of PPAR in hepatocarcinogenesis and identifies future research directions that should be taken to delineate the mechanisms underlying PPAR agonist-induced hepatocarcinogenesis. 相似文献
995.
Nakatani T Marui T Yamamoto T Kurosaka M Akisue T Matsumoto K 《Pathology international》2001,51(8):595-602
Although malignant fibrous histiocytoma (MFH) is one of the most common soft tissue sarcomas, its pathogenesis remains unclear. In this study, a cell line derived from human MFH, TNMY1, was established from a metastatic chest-wall lesion of a 60-year-old woman with MFH. The TNMY1 cell line was passaged 95 times, and it still retained the biological characteristics of the original tumor. TNMY1 consists of spindle-shaped cells and pleomorphic cells associated with multinucleated giant cells. Immunohistochemical studies showed that the spindle-shaped and pleomorphic cells were positive for vimentin, CD68 and alpha-smooth muscle actin, but negative for epithelial membrane antigen, desmin, muscle actin, alpha-sarcomeric actin, myoglobin, lysozyme and S-100 protein. The cells expressed collagen types I, III and V. These results indicate that MFH may originate from mesenchymal stem cells with the potential to differentiate into either fibroblasts or histiocytes. An elevated level of collagen type V mRNA expression is considered to support a diagnosis of MFH. 相似文献
996.
大白鼠外侧隔核的传入性神经纤维联系—HRP、荧光素法研究 总被引:2,自引:0,他引:2
本文应用HRP和荧光素标记法对大白鼠外侧隔核的传入性神经纤维联系进行了研究。实验结果表明,外侧隔核的传入神经纤维来源于端脑海马的CA_(1-4)区、杏仁皮质核、内嗅区皮质、斜角带核、视前内侧核、视前外侧核;丘脑的室周核和带旁核;底丘脑的Forel's H_2区和未定带;下丘脑的前核、外侧核、后核以及乳头体上核;中脑的腹侧被盖区。 相似文献
997.
998.
Adenoviruses 12 and 31, but not Ad18, agglutinate rat blood cells at high titer, providing suitable blood cells be available and a prolonged contact period of virus with the erythrocytes is allowed. Purified virus particles show direct, and virus-free supernatants show direct and indirect, hemagglutination, ie, enhancement of HA by heterologous antiserum. Hemagglutination inhibition with rabbit antisera shows cross-reactions between Ad12 and Ad31 with titers 4--32 times lower than with homologous antigens; Ad18 antisera react with antigens from both of the other serotypes. No cross-reactions were seen with antisera from other adenoviruses. This suggests an antigenic relationship of the three viruses of subgroup IV in their fiber antigen gamma, in addition to the known relation in the hexon (epsilon), which is apparent in cross-neutralization. 相似文献
999.
1000.
本文采用过氧化酶—抗过氧化酶(PAP)的免疫组织化学和荧光免疫组织化学的方法,研究了新生期大鼠皮下注射谷氨酸单纳(MSG)对成年后下丘脑弓状核促肾上腺皮质激素(ACTH)神经元和正中隆起内促肾上腺皮质激素释放因子(CRF)神经纤维免疫反应的影响。新生期MSG处理后,弓状核中ACTH神经元的数目明显减少,正中隆起CRF样免疫反应末稍也大大减少,减少程度随MSG剂量增大而增加。提示MSG通过损伤前阿黑皮素(POMC)衍生的神经多肽,从而影响下丘脑—垂体—肾上腺皮质轴的功能。 相似文献