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41.
Lene Mellemkjær Christoffer Johansen Martha S. Linet Gloria Gridley Jørgen H. Olsen 《Cancer causes & control : CCC》1998,9(2):183-187
Objective: Epidemiologic studies have not been able definitely to exclude that appendectomy carries a cancer risk. This study was conducted to clarify whether appendectomy is associated with a subsequent increase in cancer risk, since appendectomy is frequently an elective procedure. Methods: The present study included more than 82,000 persons who underwent appendectomy for acute appendicitis during 1977-89 according to the nation-wide Danish Hospital Discharge Register. During a follow-up interval of up to 17 years, cancer incidence was assessed by linkage to the Danish Cancer Registry and compared with the incidence in the general population of Denmark. Results: The total number of malignancies among appendectomized persons was 1.05 times higher than expected with 95 percent confidence intervals of 0.99-1.11. There was no clear significant excess of any specific cancer type. Conclusion: During a postsurgery period of nearly two decades, results of our study did not support the hypothesis that either appendectomy or acute appendicitis are likely to be associated with malignant neoplasms. 相似文献
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Transplantation of embryonic nigral tissue is used as an experimental therapy for patients with Parkinson's disease but is hampered by a limited survival rate of dopaminergic neurons. Glial cell line-derived neurotrophic factor (GDNF) is a potent survival factor for nigrostriatal dopaminergic neurons, and the present in vitro study aimed at improving the survival of dopaminergic neurons in porcine mesencephalic brain slice cultures by adding transfected, immortalized, temperature-sensitive GDNF-releasing HiB5 cells (HiB5-GDNF). Embryonic (E27/28) porcine ventral mesencephalic brain slices were placed on membrane inserts in six-well plates with serum-containing medium, and HiB5-GDNF, nontransfected HiB5 cells (HiB5-control), or green fluorescent protein-producing HiB5 cells (HiB5-GFP) were seeded onto each tissue slice. The concentration of GDNF in the coculture medium was 0.49 +/- 0.13 ng/ml at day 9 and 0. 22 +/- 0.05 ng/ml at day 19 (mean +/- SEM) as measured by GDNF ELISA. The decrease in release of GDNF over time was paralleled by a gradual reduction in the number of HiB5-GFP cells expressing the reporter gene (EGFP). At day 12, HPLC analysis revealed that medium from HiB5-GDNF cocultures contained 2.0 times more dopamine than medium from HiB5-control cocultures. At day 21 there was 1.6 times more dopamine. Similar results were obtained for the dopamine metabolite 3,4-dihydroxyphenylacetic acid. At day 21, cell counts showed that HiB5-GDNF cocultures contained 1.5 times more tyrosine hydroxylase immunoreactive neurons than HiB5-control cocultures, which must be compared with a 1.8 fold increase after chronic treatment with rhGDNF (10 ng/ml). In conclusion, the better survival of HiB5-GDNF cocultures is promising for the generation of effective cell lines for local delivery of neurotrophic factors to intracerebral nigral grafts. 相似文献
43.
B Barstad T I A S?rensen A Tj?nneland D Johansen U Becker I B Andersen M Gr?nbaek 《European journal of cancer prevention》2005,14(3):239-243
The objective was to study prospectively the relation between quantity and type of alcohol and risk of gastric cancer. In a pooled database from three population studies conducted in 1964-1992, a total of 15,236 men and 13,227 women were followed for a total of 389,051 person-years. During follow-up 122 incident cases of gastric cancer were identified. Total alcohol intake itself was not associated with gastric cancer, but type of alcohol seemed to influence risk. Compared with non-wine drinkers, participants who drank 1-6 glasses of wine had a relative risk ratio of 0.76 (95% confidence interval (CI) 0.50-1.16), whereas those who drank >13 glasses of wine per week had a relative risk ratio of 0.16 (95% CI 0.02-1.18). Linear trend test showed a significant association with a relative risk ratio of 0.60 (95% CI 0.39-0.93) per glass of wine drunk per day. These relations persisted after adjustment for age, gender, educational level, body mass index, smoking habits, inhalation and physical activity. There was no association between beer or spirits drinking and gastric cancer. In conclusion, the present study suggests that a daily intake of wine may prevent development of gastric cancer. 相似文献
44.
Simultaneous quantification of isoniazid,rifampicin, ethambutol and pyrazinamide by liquid chromatography/tandem mass spectrometry 下载免费PDF全文
Julie B. Prahl Marika Lundqvist Justyna M. C. Bahl Isik S. Johansen Åse B. Andersen Niels Frimodt‐Møller Arieh S. Cohen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(11):1004-1015
A remediable cause of poor treatment response in drug‐susceptible tuberculosis (TB) patients may be low plasma levels of one or more of the first‐line anti‐TB drugs. The aim of this work was to develop an accurate and precise LC‐MS/MS method for simultaneous quantification of all four first‐line anti‐TB drugs in plasma suitable for therapeutic drug monitoring (TDM). To adjust for degradation and losses during sample preparation, isotopically labeled compounds were used as internal standards. Plasma samples spiked with internal standards were extracted using protein precipitation with methanol and acetonitrile. Simultaneous separation of all four drugs was accomplished with a Chromolith Reversed‐Phase column and mobile phases consisting of water, methanol, ammonium acetate and formic acid with subsequent mass spectrometric quantification. The linear range of the calibration curve for isoniazid was 0.5–10 mg/L, for rifampicin 0.75–30 mg/L, for ethambutol 0.25–10 mg/L and for pyrazinamide 4–80 mg/L. The lower limit of quantification was 0.5 mg/L, 0.75 mg/L, 0.25 mg/L and 4.0 mg/L, respectively. Precision estimated by the coefficient of variation was <15% for all four drugs. The LC‐MS/MS method can readily be used for simultaneous quantification of first‐line anti‐TB drugs in plasma and is well suited for TDM. 相似文献
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47.
Omer Onur Cakir Fabio Castiglione Zafer Tandogdu Justin Collins Hussain M. Alnajjar Clare Akers Maarten Albersen Constantine Alifrangis Benjamin Ayres Oscar Brouwer Ivor Cullen Peter Hawkey Jakob Kristian Jakobsen Truls Erik Bjerklund Johansen Odunayo Kalejaiye Asheesh Kaul Bela Köves Vivekanandan Kumar Asif Muneer 《Urologic oncology》2021,39(3):197.e9-197.e17
ObjectivesTo develop an international consensus on managing penile cancer patients during the COVID-19 acute waves. A major concern for patients with penile cancer during the coronavirus disease 2019 (COVID-19) pandemic is how the enforced safety measures will affect their disease management. Delays in diagnosis and treatment initiation may have an impact on the extent of the primary lesion as well as the cancer-specific survival because of the development and progression of inguinal lymph node metastases.Materials and methodsA review of the COVID-19 literature was conducted in conjunction with analysis of current international guidelines on the management of penile cancer. Results were presented to an international panel of experts on penile cancer and infection control by a virtual accelerated Delphi process using 4 survey rounds. Consensus opinion was defined as an agreement of ≥80%, which was used to reconfigure management pathways for penile cancer.ResultsLimited evidence is available for delaying penile cancer management. The consensus rate of agreement was 100% that penile cancer pathways should be reconfigured, and measures should be developed to prevent perioperative nosocomial transmission of COVID-19. The panel also reached a consensus on several statements aimed at reconfiguring the management of penile cancer patients during the COVID-19 pandemic.ConclusionsThe international consensus panel proposed a framework for the diagnostic and invasive therapeutic procedures for penile cancer within a low-risk environment for COVID-19. 相似文献
48.
Henrik W. Schytz Faisal M. Amin Rigmor H. Jensen Louise Carlsen Stine Maarbjerg Nunu Lund Karen Aegidius Lise L. Thomsen Flemming W. Bach Dagmar Beier Hanne Johansen Jakob M. Hansen Helge Kasch Signe B. Munksgaard Lars Poulsen Per Schmidt Srensen Peter T. Schmidt-Hansen Vlasta V. Cvetkovic Messoud Ashina Lars Bendtsen 《The journal of headache and pain》2021,22(1)
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