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51.
MR perfusion imaging of pulmonary parenchyma using pulsed arterial spin labeling techniques: FAIRER and FAIR 总被引:12,自引:0,他引:12
Magnetic resonance imaging of pulmonary parenchyma perfusion using pulsed arterial spin labeling (ASL) techniques is presented. ASL uses magnetically labeled water as an endogenous, freely diffusible tracer. Presented are comparative results of ASL methods called Flow sensitive Alternating Inversion Recovery (FAIR), and FAIR with an Extra Radiofrequency pulse (FAIRER). Six healthy human volunteers were imaged. Perfusion-weighted images at different time delays, TI, were calculated from the subtraction of the control and tag images, which were acquired within a single breathhold. Detailed pulmonary structures can be visualized with negligible cardiac or respiratory motion artifacts. Different patterns of signal enhancement between the pulmonary vessels and parenchyma are shown in the perfusion images acquired at different TIs. 相似文献
52.
Cyclosporine is a powerful immunosuppressant with a narrow therapeutic window and considerable inter- and intrapatient variability.
The pre-dose trough concentration (Cmin) is commonly used for therapeutic drug monitoring. With the new microemulsion (Neoral), intrapatient variability was reduced.
However, the usefulness of Neoral Cmin was questioned. Firstly, because of the improved and more-rapid absorption, accidental intake before blood sampling has a
greater impact on Cmin than with classic cyclosporine. Secondly, Cmin may be low despite high drug exposure, due to rapid clearance in children. A full pharmacokinetic (PK) profile with determination
of the area under the curve (AUC) is expensive and cumbersome, and therefore a search for an abbreviated AUC began. Here,
we present a retrospective analysis of 84 PK profiles from 78 pediatric renal transplant recipients. By analysis of rejection
episodes and toxicity, we estimated a target AUC above 5,000 ng×h/ml in the early post-transplant period and 3,900 ng×h/ml
beyond 100 days. The abbreviated AUC using the 2- and 6-h concentrations (C2 and C6) and a simple estimate derived from the
3-h concentration (C3) were equally well correlated with the AUC. From our data, we recommend a target C3 at approximately
800 ng/ml early after transplantation and 450–550 ng/ml beyond 100 days.
Received: 28 January 1998 / Revised: 10 June 1998 / Accepted: 15 June 1998 相似文献
53.
Multidisciplinary approach to palliation of obstructive jaundice caused by a central hepatocellular carcinoma 总被引:3,自引:0,他引:3
BACKGROUND/AIMS: Obstructive jaundice due to intraductal tumour growth is a rare symptom in association with hepatocellular carcinoma (HCC). METHODS: We report a 65-year-old white male who was admitted to our department with a 2-week history of progressive jaundice. At laparotomy, the liver showed advanced cirrhosis due to long-standing biliary obstruction. Cholangiography confirmed total obstruction of the main bifurcation of the hepatic duct by intraductal tumour growth. Combination treatment with surgical segment III drainage, transcatheter arterial embolization and radioembolization with yttrium-90 resin particles and endoscopic stenting was performed. This form of treatment has never been reported before. RESULTS: With these combined procedures, relief of jaundice and a survival time of 32 months could be achieved. CONCLUSION: The combination of palliative methods may relieve jaundice, ensure a good quality of life and possibly prolong survival in patients with mechanical tumour obstruction of the biliary tree by HCC. 相似文献
54.
2-(1-Aryl-1-hydroxymethyl)- and 2-aroyl-DHAQ derivatives (DHAQ, 1,4-dihydroxy-9,10-anthraquinone), and 2-(1-aryl-1-hydroxymethyl)-ATO derivatives (ATO, anthracene-1,4,9,10-tetraone) were synthesized and their antitumor activities were determined. 2-(1-Aryl-1-hydroxymethyl)-DHAQ derivatives showed a stronger cytotoxicity compared to the series of 2-(1-hydroxyalkyl)-1,4-dihydroxy-9,10-anthraquinone derivatives. It was suggested that the presence of aryl group at the side chain accelerated the bioreductive activation leading to cell death. 2-Aroyl-DHAQ derivatives, despite their higher electrophilicity, revealed smaller cytotoxicity and antitumor activity (expressed by T/C value) than 2-(1-aryl-1-hydroxymethyl)-DHAQ derivatives. Thus, no consistent relationship between the electronic effect on aromatic side chain and the cytotoxicity was observed. ATO series exhibited a higher antitumor activity (T/C, 125 to approximately 218%), though their cytotoxicity was not further improved compared to that of 2-(1-aryl-1-hydroxymethyl)-1,4-dihydroxy-9,10-anthraquinones. They manifested no correlation between the cytotoxicity and the antitumor activity. In case of 2-[1-hydroxy-1-(4-propylphenyl)-methyl]-ATO, the most bioactive one in vivo among the same series, it showed an ED50 value of 10.2 mg/mL and a T/C value of 218%. It is assumed that the anthracene-1,4,9,10-tetraones after uptake into cellular tissues might be transformed to a cytotoxic metabolite(s). 相似文献
55.
Takahashi Y Mai M Wilson M Kitadai Y Bucana C Ellis L 《International journal of oncology》1996,8(4):701-705
To determine the role of site of tumor implantation on tumor angiogenesis, we implanted gastric cancer cells in the orthotopic (stomach) and ectopic (subcutaneous) locations in nude mice. Tumors in the stomach demonstrated greater vascularization, higher levels of vascular endothelial growth factor (VEGF) expression, and greater proliferation compared with tumors in the subcutaneous tissues. These data suggest that the relationships among the expression of VEGF, vascularization, and proliferation of human gastric cancer cells are regulated by the organ microenvironment. In addition, VEGF may provide a target for anti-angiogenic therapy for gastric cancers. 相似文献
56.
RELATIONSHIP BETWEEN CORNEAL DELLEN AND TEARFILM BREAKUP TIME 总被引:1,自引:0,他引:1
Guanghuan Mai Shaomei Yang Eye Hospital Zhangshan Ophthalmic Center Sun Yat-sen University of Medical Sciences Guangzhou China 《眼科学报》1991,7(1):43-46
The BUT of 51 strabismus patients were measured before and after operation. The average pre-op BUT was 28.75 seconds(10.96"-91.80"). The post-op BUT in all operated eyes were reduced significantly, no matter what procedures had been performed and whether dellen appeared or not(P<0.01). The BUT in the group complicated dellen reduced from 23.22"(pre-op) to 8.61"(post-op). The incidence of dellen was 22.54% in this study. The incidence of dellen after rectus resection procedure(47.75%) was much higher than that after rectus recession(5.13%)(P<0.01). This study showed that dellen was closelyre related to the BUT and occurred more often in the eyes on which resection procedure was performed. It is considered that excessive lacrimation and elevation of the bulbar conjunctiva near the limbus may disturb the stability of the precornea tearfilm and cause the tearfilm break up earlier. Local corneal dehydration and dellen formation may be caused by reduced BUT. The incidence of dellen after operation may be higher if the cornea was carefully observed. 相似文献
57.
Malin F. Böttcher Jenny Bjurström Xiao-Mei Mai Lennart Nilsson Maria C. Jenmalm 《Pediatric allergy and immunology》2003,14(5):345-350
Atopic asthma is characterized by excessive T helper 2 (Th2)-like immunity to allergens in the bronchial mucosa. The Th2-cytokine interleukin (IL)-4 induces IgE production, while the Th2-cytokine IL-5 promotes eosinophilic inflammation in the airways of asthmatics. Most asthmatics are atopic, but a subgroup is non-atopic. We hypothesize that allergen-induced Th2, particularly IL-5, responses can be observed in peripheral blood in both atopic and non-atopic asthmatic children but not in healthy control children. The aim of the present study was to determine IL-4, IL-5, IL-9, IL-10, IL-13 and IFN-γ secretion induced from peripheral blood mononuclear cells (PBMC) by a broad panel of inhalant allergens (timothy, cat, birch, dog and house dust mite) in asthmatic children with and without sensitization. The study included 13 atopic asthmatic, 5 non-atopic asthmatic, and 12 non-atopic non-asthmatic children. PBMC were stimulated with allergens and cytokine production was measured with enzyme-linked immunosorbent assay (ELISA). Higher levels of cat and dog antigen-induced IL-5 release were more commonly observed in both atopic and non-atopic asthmatics than in controls. Children with atopic, but not non-atopic, asthma produced higher levels of allergen-induced IL-4 and IL-9 than controls. Non-atopic asthmatics produced more IL-10 than atopic asthmatics after cat stimulation. High levels of eosinophilia-associated IL-5 responses are induced by cat and dog allergen in both atopic and non-atopic asthmatic children. The Th2 cytokines IL-4 and IL-9 were associated only with atopic asthma, probably due to their IgE-inducing properties. 相似文献
58.
目的 建立一种快速有效的分析方法 ,达到鉴定淫羊藿及人参复方产品中黄酮苷类及人参皂苷类成分 ,并测定各成分含量的目的 ,最终控制复方中淫羊藿及人参的比例。方法 通过反相液相色谱 ,对包括药典所收载的淫羊藿药材及其产品进行分析。淫羊藿中的主要黄酮苷类成分 ,以淫羊藿定A、淫羊藿定B、淫羊藿定C、淫羊藿苷为对照品 ;对主要的人参皂苷类成分 ,以人参皂苷Rg1 、Re、Rf、Rb1 、Rb2 、Rd为对照品。结果 在同一色谱条件下 ,对主要黄酮苷类及人参皂苷类成分均可同时测定且分离良好。结论 该方法适用于淫羊藿、人参及其复方产品中淫羊藿黄酮苷类、人参皂苷类成分的定性、定量分析 相似文献
59.
胃癌7号染色体长臂的杂合性缺失分析 总被引:2,自引:0,他引:2
目的:检测胃癌患者7号染色体长臂微卫星位点的杂合性缺失(loss of heterozygosity,LOH),以初步确定7号染色体长臂上与胃癌相关基因连锁最密切的微卫星多态位点及LOH的临床意义.方法:在70例原发性胃癌中应用多重PCR技术扩增覆盖整个7号染色体长臂的9个微卫星位点(平均遗传距离为10cm),聚丙烯酰胺凝胶电泳分离PCR产物,用GeneScan、Genotyper软件进行分析.结果:9个微卫星位点的LOH均可发生于原发性胃癌,总的LOH频率为34.3%(24/70),其中D7S486和D7S798位点的LOH频率较高,分别为24.0%(12/50)和19.2%(5/26);总的LOH频率随临床分期而显著增高(P=0.046),D7S486位点的LOH频率在淋巴结转移者显著高于无淋巴结转移者(P=0.015).结论:在7号染色体长臂D7S486和D7S798位点附近,可能存在与胃癌发展相关的抑癌基因. 相似文献
60.
David Finkle Zhi Ricky Quan Vida Asghari Jessica Kloss Nazli Ghaboosi Elaine Mai Wai Lee Wong Philip Hollingshead Ralph Schwall Hartmut Koeppen Sharon Erickson 《Clinical cancer research》2004,10(7):2499-2511
PURPOSE: This study examined the effectiveness of early and prolonged mu4D5 (the murine form of trastuzumab/Herceptin) treatment in transgenic mice that overexpress human HER2 (huHER2), under the murine mammary tumor virus promoter, as a model of huHER2-overexpressing breast cancer. EXPERIMENTAL DESIGN: Mice were randomly assigned to one of three treatment groups and received i.p. injections from 17 weeks of age until either 52 weeks of age or morbidity. Fourteen mice received 100 mg/kg mu4D5, 14 mice received 100 mg/kg antiherpes simplex virus glycoprotein D control antibody, and 11 mice received a diluent control. RESULTS: High levels of huHER2 expression were detectable in mammary glands of young virgin founder mice. Mammary adenocarcinomas were frequently found in female founders and progeny at an average age of 28 weeks, with some progressing to metastatic disease. The incidence of mammary tumors was significantly reduced, and tumor growth inhibition was observed in mice receiving mu4D5 compared with control mice. In addition, Harderian gland neoplasms, highly associated with overexpression of huHER2 in this transgenic line, were entirely absent in the mu4D5 treatment group, indicating down-regulation of huHER2 in vivo activity. CONCLUSIONS: Early intervention with mu4D5 was of benefit in our transgenic mice at high risk for developing huHER2-overexpressing breast cancer. This study suggests a potential benefit of early treatment with Herceptin in HER2-positive primary breast cancer. 相似文献