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Background: Neuroendocrine tumors usually present with inoperable metastatic disease and severe hormonal symtoms. Specific chemotherapy, alpha-interferon and the somatostatin analog octreotide are established therapies in these patients but all of them eventually fail. Other somatostatin analogs, e.g., RC-160 and lanreotide, are currently being studied in different doses and modes of administration.Patients and methods: Nineteen patients with advanced neuroendocrine gastrointestinal tumors [13 carcinoids and six endocrine pancreatic tumors (EPT)], liver metastases being present in 18, most of them heavily pretreated, were included. Seventeen out of 18 patients had somatostatin receptors demonstrated by octreotide scintigraphy. Lanreotide was given as four daily subcutaneous injections, starting with 750 µg/d, then increasing every week up to 12,000 µg/d after six weeks, a dose which was maintained, if tolerated, for 12 months, or until progression.Results: There was a significant tumor size response (>50%) in one patient (5%), whereas 12 patients (70%) had tumor stabilization for 12 months. Bichemical tumor markers were significantly reduced at six months (urinary 5-hydroxyindoleacetic acid and plasma chromogranin) and 12 months (chromogranin) and the overall biochemical response rate was 58% with this high dose of lanreotide. Adverse events were observed and four patients stopped the treatment due to adverse events. Studies of tumor biopsies before and during treatment indicated induction of apoptosis in patients with tumor stabilization and biochemical response.Conclusion: High-dose treatment with lanreotide (12,000 µg/d) produced tumor size response in 5%, stabilization in 70% and a biochemical response in 58% of patients. These results should be related to the advanced stage of the disease as indicated by the mean duration of disease of more than four years, but they do not appear to be better than those achieved with standard doses of somatostatin analogs. However, in responding patients we observed induction of apoptosis in the tumors, a phenomenon not seen with regular doses of somatostatin analogs, but often produced by chemotherapeutic agents. 相似文献
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WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
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Intra-arterial tissue adhesive for medical splenectomy in humans 总被引:2,自引:0,他引:2
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H Khalili A Soudbakhsh M Hajiabdolbaghi S Dashti-Khavidaki A Poorzare AA Saeedi R Sharififar 《BMC infectious diseases》2008,8(1):165
Background
Human immunodeficiency virus infected individuals are prone to malnutrition due to increased energy requirements, enteropathy and increased catabolism. Trace elements such as zinc and selenium have major role in maintaining a healthy immune system. This study was designed to evaluate the nutritional status of Iranian subjects who were newly diagnosed with human immunodeficiency virus infection and to compare serum level of zinc and selenium in these patients with those of the sex and aged match healthy subjects. 相似文献17.
背景目前已开展了对重性精神病患者进提供连续性服务的研究。目的探讨基层对有抑郁症风险患者提供连续性服务的水平,并与对心力衰竭患者的服务水平进行对比。方法采用抑郁症风险患者与心力衰竭患者对比的探索性研究。采用患者问卷评估服务的持续性,包含如下内容:(1)联系的服务提供者数(个人连续性);(2)诊所内服务提供者之间的合作(团队连续性)(6个项目,分数1~5分);(3)诊所外全科医师与服务提供者之间的合作(跨界连续性)(4个项目,分数1~5分)。结果大多数抑郁症风险患者在过去1年中寻遍整个服务提供界联系了几个服务提供者,曾遇到过高水平团队连续性服务及低水平跨界连续性服务。在诊所中可接触到的不同服务提供者要明显多于心力衰竭患者服务提供者(P<0.01)。抑郁症风险患者的服务提供者之间的合作更好一些,每项平均得分4.3分,心力衰竭患者得分为4.0分(P=0.03)。然而,跨界连续性服务方面正好相反:抑郁症风险患者每项平均得分3.5分,心力衰竭患者得分为4.0分(P=0.01)。结论抑郁症风险患者与心力衰竭患者之间的探索性对比显示:体验服务连续性方面的差距不大。对此还应行进一步分析。 相似文献
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CHO-K1, COS-7, and Rat2 fibroblast cell lines are generally believed to be devoid of estrogen receptors (ERs) and have been widely used to study the functions of ER-alpha and ER-beta after transfection of their cDNAs. Numerous studies have demonstrated that transfected ER-alpha or ER-beta mediates estradiol-induced activation of multiple signaling pathways, including the MAPK/ERK pathways. We report here for the first time that both 17alpha-estradiol and 17beta-estradiol elicit activation of MAPK/ERK in native, nontransfected CHO-K1, COS-7, and Rat2 fibroblast cell lines. We further report that, contrary to the generally held belief, these cell lines are not unresponsive to estradiol in their native, nontransfected state, and that this estrogen responsiveness is associated with estrogen binding. Using multiple ER antibodies, we failed to find ER-alpha or ER-beta isoforms or even ER-X. In view of these findings, researchers, using such cells as models to investigate mechanisms of estrogen action, must always take into account the existence of endogenous estrogen binding proteins other than ER-alpha, ER-beta, or ER-X. 相似文献
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