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81.
Association of SULT1A1 phenotype and genotype with prostate cancer risk in African-Americans and Caucasians. 总被引:3,自引:0,他引:3
Susan Nowell D Luke Ratnasinghe Christine B Ambrosone Suzanne Williams Terri Teague-Ross Lyndsey Trimble Gail Runnels Alindria Carrol Bridgett Green Angie Stone Don Johnson Graham Greene Fred F Kadlubar Nicholas P Lang 《Cancer epidemiology, biomarkers & prevention》2004,13(2):270-276
Exposure to heterocyclic amines may increase prostate cancer risk. Human sulfotransferase 1A1 (SULT1A1) is involved in the bioactivation of some dietary procarcinogens, including the N-hydroxy metabolite of the food-borne heterocyclic amine, 2-amino-1-methyl-6-phenylimidazo(4,5-b) pyridine. This study compares a polymorphism in the SULT1A1 gene, SULT1A1 enzyme activity, meat consumption, and the risk of prostate cancer in a population based case-control study. Prostate cancer patients (n = 464) and control individuals (n = 459), frequency matched on age and ethnicity, provided informed consent, answered a survey, and provided a blood sample. Platelets were isolated for phenotype analysis, and DNA was isolated from lymphocytes for genotype determination. Meat consumption was assessed using a dietary questionnaire. Caucasians homozygous for the SULT1A1*1 high activity allele were at increased risk for prostate cancer [odds ratio (OR), 1.68; 95% confidence interval (CI), 1.05-2.68] compared with individuals homozygous for the low-activity allele. The association between SULT1A1 genotype and prostate cancer risk in African-Americans did not reach significance (OR, 1.60; 95% CI, 0.46-5.62). When SULT1A1 activity was considered, there was a strong association between increased SULT1A1 activity and prostate cancer risk in Caucasians (OR, 3.04; 95% CI, 1.8-5.1 and OR, 4.96; 95% CI, 3.0-8.3, for the second and third tertiles of SULT1A1 activity, respectively) compared with individuals in the low enzyme activity tertile. A similar association was also found in African-American patients, with ORs of 6.7 and 9.6 for the second and third tertiles of SULT1A1 activity (95% CI, 2.1-21.3 and 2.9-31.3, respectively). When consumption of well-done meat was considered, there was increased risk of prostate cancer (OR, 1.42; 95% CI, 1.01-1.99 and OR, 1.68; 95% CI, 1.20-2.36 for the second and third tertiles, respectively). When SULT1A1 activity was stratified by tertiles of meat consumption, there was greater risk of prostate cancer in the highest tertile of meat consumption. These results indicate that variations in SULT1A1 activity contributes to prostate cancer risk and the magnitude of the association may differ by ethnicity and be modified by meat consumption. 相似文献
82.
MJ Stevens PD Stricker J Saalfeld PC Brenner R Kooner GFA O'Neill PJ Duval RS Jagavkar P Cross J Martland 《Journal of Medical Imaging and Radiation Oncology》2003,47(2):152-160
Combination high dose rate brachytherapy (HDRB) and external beam radiation therapy is technically and clinically feasible as definitive treatment for localized prostate cancer. We report the first large Australian experience using this technique of radiation dose escalation in 82 patients with intermediate‐ and high‐risk disease. With a median follow up of 3 years (156 weeks), complications were low and overall prostate‐specific antigen progression‐free survival was 91% using the American Society for Therapeutic Radiology and Oncology consensus definition. The delivery of hypofractionated radiation through the HDRB component shortens overall treatment time and is both biologically and logistically advantageous. As a radiation boost strategy, HDRB is easy to learn and could be introduced into most facilities with brachytherapy capability. 相似文献
83.
Tyrosinemia type I is an autosomal recessive inherited defect of tyrosine metabolism. The underlying cause is a defect of fumarylacetoacetate hydrolase. The disease affects the liver (acute liver failure, liver cirrhosis, hepatocellular cancer), the kidney (tubulopathy with hypophosphatemic rickets), and the peripheral nervous system (paresthesia, vegetative symptoms, progressive paralysis). Beside the hypertyrosinemia the diagnosis can be made on the basis of urinary excretion of a pathological metabolite of the tyrosine metabolism (succinylacetone). Therapeutic options are a regulated phenylalanine/tyrosine diet, a very effective drug therapy (NTBC) that has been available for several years, and in cases of acute liver failure or end-stage liver cirrhosis a liver transplantation. 相似文献
84.
Ohne Zusammenfassung 相似文献
85.
PD Dr. F. Bahlmann 《Der Gyn?kologe》2004,37(8):725-736
In monochorionic twin pregnancies, the risk of developing a twin to twin transfusion syndrome is between 15 and 20%. Using high-resolution ultrasound machines, sonographic images demonstrate the detailed features of placental development. The lambda sign was established for the diagnosis of dichorionic placenta and the T sign for monochorionic placenta at the end of the first trimester. Other sonographic findings of the twin to twin transfusion syndrome are monochorionicity, same sex, polyhydramnios, permanently filled bladder in the recipient, and oligo/anhydramnios of the donor with a slightly filled or empty bladder. Fetoscopic laser treatment has become an accepted procedure to coagulate the placental anastomoses. This development is supported by actual studies about psycho- and neuromotoric development in early childhood, which shows a lower rate of disabled children in the group receiving laser therapy in comparison to the group undergoing amnioreduction. Twin pregnancies complicated by twin to twin transfusion syndrome should be treated in specialized prenatal centers. 相似文献
86.
PD Dr. T. Moser N. Strenzke A. Meyer A. Lesinski-Schiedat T. Lenarz D. Beutner A. Foerst R. Lang-Roth H. von Wedel M. Walger M. Gross A. Keilmann A. Limberger T. Steffens J. Strutz 《HNO》2006,54(11):833-841
Pathological auditory brainstem responses (lack of responses, elevated thresholds and perturbed waveforms) in combination with present otoacoustic emissions are typical audiometric findings in patients with a hearing impairment that particularly affects speech comprehension or complete deafness. This heterogenous group of disorders first described as “auditory neuropathy” includes dysfunction of peripheral synaptic coding of sound by inner hair cells (synaptopathy) and/or of the generation and propagation of action potentials in the auditory nerve (neuropathy). This joint statement provides prevailing background information as well as recommendations on diagnosis and treatment. The statement focuses on the handling in the german language area but also refers to current international statements. 相似文献
87.
Minimally invasive diagnostic procedures for the breast under mammography, ultrasound, and magnetic resonance guidance have led to a higher specificity of imaging techniques and a decrease in open biopsy of the breast. The percutaneous approach is more cost and time effective and reduces morbidity compared with open biopsy. The “Step-3-guideline for early breast cancer detection in Germany” represents the first national guidelines for a nationwide, quality assured, early breast cancer detection program, including recommendations for minimally invasive breast diagnostics. Indications for ultrasound guided vacuum biopsy of the breast are summarized in the “Consensus on the use and technique of vacuum-assisted sonographic breast biopsy” by the Study Group on Minimally Invasive Breast Interventions (AG MiMi) of the German Society of Senology (DGS). 相似文献
88.
Zusammenfassung Beim differenzierten Schilddrüsenkarzinom besteht bei nicht Organkapsel überschreitendem Tumorwachstum und adäquater Operation keine Indikation zur postoperativen Bestrahlung. Bei Patienten mit Organkapsel überschreitendem Wachstum wird nach vollständiger Resektion der Nutzen einer zusätzlichen perkutanen Radiotherapie kontrovers diskutiert. Die MSDS-Studie (Multizenterstudie Differenziertes Schilddrüsenkarzinom), die eine Randomisierung genau zu dieser Fragestellung durchführte, musste aufgrund der mangelnden Rekrutierung vorzeitig beendet werden. Beim anaplastischen Schilddrüsenkarzinom wird die vollständige Resektion angestrebt. Die postoperative Bestrahlung ist dann obligat. Bei Therapieprotokollen mit zusätzlicher Adriamycingabe konnten erhöhte lokale Kontroll- und Überlebensraten beobachtet werden. Bei medullärem Schilddrüsenkarzinom und inkompletter Tumorresektion geht eine additive Radiotherapie mit einer verbesserten lokalen Kontrolle einher. Bei nicht Radiojod speichernden Metastasen des Schilddrüsenkarzinoms wird die Radiotherapie im Bereich des Knochens bei Schmerzen, Frakturgefahr oder Myelonkompression eingesetzt. 相似文献
89.
Zusammenfassung Multimodale Therapiestrategien, die Chirurgie, Strahlen- und Chemotherapie kombinieren, haben die Behandlungsergebnisse bei Tumoren der Lunge und der Kopf-Hals Region verbessert. Die Ergänzung des Therapiespektrums um weitere Ansätze, die sich in der Wirkungsweise und möglichst durch reduzierte Toxizität von den konventionellen unterscheiden, erscheint jedoch zur Erzielung weiterer Fortschritte notwendig. Eine neue Generation immunologischer passiver (antikörperbasierter) und auch aktiver (Vakzinierungs-) Strategien erscheint aussichtsreich und befindet sich gegenwärtig in der klinischen Prüfung. Die Untersuchung der optimalen zeitlichen Sequenz in Kombination mit den konventionellen Therapieverfahren und die Individualisierung der Therapie auf Basis genomischer/proteomischer Daten muss die klinische Integration begleiten. 相似文献
90.
The aim of treatment in isolated locally recurrent rectal cancer is R0 resection, which is possible in 30%. Because of the high rate of surgical complications after repeat surgery in the pelvis, preoperative staging has to be precise to estimate the extent and location of the recurrent rectal cancer. After exclusion of distant metastases, surgery should be considered following preoperative radiochemotherapy if possible. When a curative treatment concept is not indicated, radiotherapy is the best treatment choice. This paper presents various tabularised summaries about therapeutic strategies in isolated locally recurrent rectal cancer. 相似文献