Education and Specialization
1993 - Çukurova University, Faculty of Medicine, Graduation
1999 - Cumhuriyet University, Internal Medicine Specialization
2004 - Turkey High Specialization Hospital, Gastroenterology Specialization

Experience
2004-2008 - Ankara Numune Training and Research Hospital
2009-2012 - Dışkapı Yıldırım Beyazıt Training and Research Hospital
2012-2016 - Hacettepe University
2015-2016 - Massachusetts General Hospital, Harvard Medical School
2017-2020 - Private Eryaman Hospital

Professional Memberships
Turkish Society of Gastroenterology
Gastrointestinal Endoscopy Association
Turkish Liver Research Society
Viral Hepatitis Combat Association
European Gastroenterology Board
American Gastroenterological Association
Asian Pacific Association for the Study of Liver

1. Ozturk O, Koklu H, Akbal E, Aksoy EK, Altan E, Basar O, Yuksel O, Arslan S, Koklu S. Diverticular disease and posture during defecation : a prospective comparative study. Acta Gastroenterol Belg. 2018 Oct-Dec;81(4):490-495. PMID: 30645917.
2. Basar O, Yuksel O, Yang DJ, Samarasena J, Forcione D, DiMaio CJ, Wagh MS, Chang K, Casey B, Fernandez-Del Castillo C, Pitman MB, Brugge WR. Feasibility and safety of microforceps biopsy in the diagnosis of pancreatic cysts. Gastrointest Endosc. 2018 Jul;88(1):79-86. doi: 10.1016/j.gie.2018.02.039. Epub 2018 Mar 3. PMID: 29510146.
3. Franses JW, Basar O, Kadayifci A, Yuksel O, Choz M, Kulkarni AS, Tai E, Vo KD, Arora KS, Desai N, Licausi JA, Toner M, Maheswaran S, Haber DA, Ryan DP, Brugge WR, Ting DT. Improved Detection of Circulating Epithelial Cells in Patients with Intraductal Papillary Mucinous Neoplasms. Oncologist. 2018 Jan;23(1):121-127. doi: 10.1634/theoncologist.2017-0234.
4. Yilmaz B, Aktas B, Altinbas A, Ginis Z, Ozturk G, Ekiz F, Kilincalp S, Deveci M, Simsek Z, Coban S, Basar O, Yuksel O. The Role of M30 in Predicting the Severity of Liver Fibrosis and Inflammation in Chronic Hepatitis B Patients. Hepat Mon. 2016 Aug 10;16(9):e35640. doi: 10.5812/hepatmon.35640. PMID: 27822256; PMCID: PMC5088916.
5. Ekiz Ö, Çelik E, Balta İ, Bülbül Şen B, Rifaioğlu EN, Demir M, Ekiz F, Başar Ö, Yüksel O. Nail changes in patients with inflammatory bowel diseases. Turk J Med Sci. 2016 Feb 17;46(2):495-500. doi: 10.3906/sag-1502-139. PMID: 27511517.
6. Ozturk O, Koklu S, Basar O, Purnak T, Yuksel O. An unusual cause of anemia in an elder: isolated splenic hemangiomatosis and hemorrhagic telangiectasia. Gastroenterol Nurs. 2016 Jul-Aug;39(4):317-8. doi: 10.1097/SGA.0000000000000244. PMID: 27467061.
7. Ozturk O, Koklu S, Basar O, Purnak T, Yuksel O. Crohn disease presented with a giant colonic mass. Gastroenterol Nurs. 2016 May-Jun;39(3):235-7. doi: 10.1097/SGA.0000000000000249. PMID: 27258465.
8. Ekiz F, Yuksel İ, Arikök AT, Yilmaz B, Altinbas A, Aktas B, Deveci M, Basar O, Coban S, Yuksel O. Will a second biopsy sample affect treatment decisions in patients with chronic hepatitis B? Hepatol Int. 2016 Jul;10(4):602-5. doi: 10.1007/s12072-015-9666-5. Epub 2015 Sep 28. PMID: 26416085.
9. Karaahmet F, Basar O, Coban S, Aydoğ G, Yuksel O. Signet Ring Cell Carcinoma of Both Colon and Pancreas. J Gastrointest Cancer. 2015 Dec;46(4):445-6. doi: 10.1007/s12029-015-9763-7. PMID: 26386689.
10. Dede F, Ayli D, Gonul I, Yuksel O, Ozturk R, Yildiz A, Yenigun E, Piskinpasa S, Turgut D, Koc E, Odabas AR. The effect of Helicobacter pylori eradication on proteinuria in patients with primary glomerulonephritis. Arch Med Sci. 2015 Aug 12;11(4):764-9. doi: 10.5114/aoms.2013.37013. Epub 2013 Aug 20. PMID: 26322088; PMCID: PMC4548018.
11. Çiftci A, Yilmaz B, Köklü S, Yüksel O, Özsoy M, Erden G, Öztürk G, Akbal E, Ergül B, Koçak E, Cesur S. Serum levels of nitrate, nitrite and advanced oxidation protein products (AOPP) in patients with nonalcoholic fatty liver disease. Acta Gastroenterol Belg. 2015 Jun;78(2):201-5. PMID: 26151688.
12. Altinbaş A, Yilmaz B, Aktaş B, Ekiz F, Şimşek Z, Başar Ö, Çoban Ş, Yüksel O. What is the main target: a clearer colon with a sennoside-based regime, or adequate bowel cleansing before colonoscopy with a PEG-EL-based regime? Turk J Med Sci. 2015;45(2):404-8. doi: 10.3906/sag-1402-86. PMID: 26084134.
13. Örmeci N, Özbaş B, Güner R, Özkan H, Yalçı A, Çoban Ş, Dökmeci A, Kalkan Ç, Akıncı H, Yüksel O, Başar Ö, Yüksel İ, Balık İ. Tenofovir-best hope for treatment of chronic hepatitis B infection? Turk J Gastroenterol. 2015 Jul;26(4):322-7. doi: 10.5152/tjg.2015.0164. Epub 2015 Jun 2. PMID: 26038999.
14. Koklu S, Gulsen MT, Tuna Y, Koklu H, Yuksel O, Demir M, Guner R, Dogan Z, Kucukazman M, Poyrazoglu OK, Biyik M, Ozturk NA, Aydogan T, Coban S, Kocaman O, Sapmaz F, Gokturk SH, Karaca C, Demirezer A, Tanoglu A, Yildirim B, Altinbas A, Atak BM, Cosar AM, Alkan E; Other collaborators. Differences in nephrotoxicity risk and renal effects among anti-viral therapies against hepatitis B. Aliment Pharmacol Ther. 2015 Feb;41(3):310-9. doi: 10.1111/apt.13036. Epub 2014 Dec 4. PMID: 25982037.
15. Arslan MS, Ekiz F, Deveci M, Sahin M, Topaloglu O, Karbek B, Tutal E, Ginis Z, Cakal E, Ozbek M, Yuksel O, Delibasi T. The relationship between cytotoxin-associated gene A positive Helicobacter pylori infection and autoimmune thyroid disease. Endocr Res. 2015;40(4):211-4. doi: 10.3109/07435800.2015.1015727. Epub 2015 May 13. PMID: 25970504.
16. Aktaş B, Başyiğit S, Yüksel O, Akkan T, Atbaşı ST, Uzman M, Yılmaz B, Şimşek G, Nazlıgül Y. The impact of amalgam dental fillings on the frequency of Helicobacter pylori infection and H. pylori eradication rates in patients treated with concomitant, quadruple, and levofloxacin-based therapies. Eur J Gastroenterol Hepatol. 2015 Jul;27(7):769-75. doi: 10.1097/MEG.0000000000000372. PMID: 25919773.
17. Altinbaş A, Çoban Ş, Başar Ö, Yüksel O. Utility of M30, an apoptotic serum marker, in liver diseases. Turk J Med Sci. 2015;45(1):6-10. doi: 10.3906/sag-1309-14. PMID: 25790523.
18. Ozturk O, Basar O, Koklu S, Yuksel O, Purnak T, Sokmensuer C. An unusual presentation of malignant melanoma: amelanotic gastric metastasis. Am J Gastroenterol. 2015 Mar;110(3):476. doi: 10.1038/ajg.2014.434. PMID: 25743721.
19. Purnak T, Yuksel O. Overview of venous thrombosis in inflammatory bowel disease. Inflamm Bowel Dis. 2015 May;21(5):1195-203. doi: 10.1097/MIB.0000000000000274. PMID: 25581828.
20. Caner S, Altinbaş A, Yeşıl Y, Beyazit Y, Yilmaz B, Yüksel O. The relation between Helicobacter pylori and ulcerative colitis. Turk J Med Sci. 2014;44(5):820-3. doi: 10.3906/sag-1305-39. PMID: 25539552.
21. Oztürk O, Köklü S, Yüksel O. Constipation: an unusual presentation of ulcerative pancolitis in an elderly adult. J Am Geriatr Soc. 2014 Oct;62(10):2013-4.
22. Aktaş B, Coban S, Başar O, Yaman S, Yılmaz B, Ekiz F, Yüksel O. Fulminant liver failure and renal failure related with malva sylvestris. Turk J Gastroenterol. 2014 Aug;25(4):437.
23. Hamamci M, Karaahmet F, Ekiz F, Yuksel O, Başar O, Coban S. Like a pearl: a rare, white, common bile duct stone in an elderly adult. J Am Geriatr Soc. 2014 Sep;62(9):1816.
24. Yılmaz B, Köklü S, Yüksel O, Arslan S. Serum beta 2-microglobulin as a biomarker in inflammatory bowel disease. World J Gastroenterol. 2014 Aug 21;20(31):10916-20.
25. Aktaş B, Başar O, Yılmaz B, Ekiz F, Altınbaş A, Coban S, Büyükçam F, Albayrak A, Giniş Z, Yüksel O, Delibaşı T. Serum M30 and M65 levels and effects of Ankaferd blood stopper in cerulein induced experimental acute pancreatitis model in rats. Int J Clin Exp Med. 2014 Jul 15;7(7):1676-83
26. Aktaş B, Coban S, Simşek Z, Başar O, Arıkök AT, Yüksel O. Carcinoid tumor of the minor duodenal papilla: a rare entity in elderly individuals. J Am Geriatr Soc. 2014 Oct;62(10):2006-8.
27. Altınbaş A, Ekiz F, Başar Ö, Kılınçalp S, Yılmaz B, Aktaş B, Yüksel O. Drinking pineapple juice for undigested food in stomach. Turk J Gastroenterol. 2014 Apr;25(2):220-1.
28. Yilmaz B, Basar O, Altınbas A, Ekiz F, Aktas B, Oztürk G, Ginis Z, Coban S,Ucar E, Erarslan E, Coskun Y, Yüksel I, Tuna Y, Yüksel O. The utility of thrombopoietin in predicting liver fibrosis in chronic hepatitis B. Int J Clin Exp Med. 2014 May 15;7(5):1430-4.
29. Yilmaz B, Basar O, Aktas B, Altinbas A, Ekiz F, Büyükcam F, Albayrak A, Ginis Z, Oztürk G, Coban S, Ucar E, Kaya O, Yüksel O, Caner S, Delibasi T. Effects of urtica dioica extract on experimental acute pancreatitis model in rats. Int J Clin Exp Med. 2014 May 15;7(5):1313-8.
30. Karaahmet F, Coban S, Basar O, Yuksel O. Successful treatment of a large choledochal inflammatory polyp in a patient with cutaneous neurofibromatosis. Endoscopy. 2014;46 Suppl 1 UCTN:E113.
31. Koklu S, Gulsen MT, Tuna Y, Koklu H, Yuksel O, Yilmaz B, Karaca C, Ataseven H, Guner R, Kucukazman M, Kockar C, Demir M, Poyrazoglu OK, Ibis M, Purnak T,Etgul S, Alkan E, Coban S, Gokturk S, Biyik M, Baykal O, Basar O, Koklu N, Tatar G, Simsek H. Lamivudine treatment failure risks in chronic hepatitis B patients with low viral load. Digestion. 2013;88(4):266-71.
32. Yılmaz B, Çoban Ş, Usküdar O, Şimşek Z, Aktaş B, Yüksel O. Successful treatment of postpolypectomy colonic hemorrhage with a combination of hemoclip and endoscopic band ligation. Turk J Gastroenterol. 2013;24(4):375-6.
33. Yılmaz B, Altınbaş A, Ekiz F, Yüksel I, Çoban Ş, Yüksel O. An unexpected cause of acute colonic obstruction: globe vesicale. Turk J Gastroenterol.2013;24(4):372-3.
34. Simşek Z, Altınbaş A, Delibaşı T, Yüksel O. Incomplete stomach emptying as a complication of intragastric balloon treatment and a solution suggestion:Pineapple juice drinking. Turk J Gastroenterol. 2013;24(4):330-3.
35. Altınbas A, Aktas B, Yılmaz B, Ekiz F, Deveci M, Basar O, Simsek Z, Coban S, Tuna Y, Uyar MF, Yuksel O. Adding pineapple juice to a polyethylene glycol-based bowel cleansing regime improved the quality of colon cleaning. Ann Nutr Metab. 2013;63(1-2):83-7.
36. Aktaş B, Altınbaş A, Başar O, Yılmaz B, Ekiz F, Giniş Z, Oztürk G, Coban S,Tuna Y, Uçar E, Erarslan E, Yüksel O. Serum m 30 levels reflects ulcerative colitis activity. Inflamm Bowel Dis. 2013 Oct;19(11):2400-3.
37. Purnak T, Beyazit Y, Efe C, Ozaslan E, Yuksel O, Altiparmak E. Authors' reply: 'Mean platelet volume could be a promising biomarker to monitor dietary compliance in celiac disease'. Ups J Med Sci. 2013 Aug;118(3):208.
38. Altinbas A, Hamamci M, Karakose M, Delibasi T, Yuksel O. Pineapple juice ingestion for gastric discomfort in diabetic gastroparesis. Acta GastroenterolBelg. 2013 Mar;76(1):72-3.
39. Kılınçalp S, Ekiz F, Başar O, Ayte MR, Coban S, Yılmaz B, Altınbaş A, Başar N, Aktaş B, Tuna Y, Erbiş H, Uçar E, Erarslan E, Yüksel O. Mean platelet volume could be possible biomarker in early diagnosis and monitoring of gastric cancer. Platelets. 2014;25(8):592-4.
40. Ucar F, Sezer S, Ginis Z, Ozturk G, Albayrak A, Basar O, Ekiz F, Coban S,Yuksel O, Armutcu F, Akbal E. APRI, the FIB-4 score, and Forn's index have noninvasive diagnostic value for liver fibrosis in patients with chronic hepatitis B. Eur J Gastroenterol Hepatol. 2013 Sep;25(9):1076-81.
41. Simsek Z, Karaahmet F, Yuksel O, Yilmaz B, Coban S. Successful endoscopic treatment of massive bleeding related to the appendiceal stump. Endoscopy. 2013;45 Suppl 2 UCTN:E15.
42. Kilincalp S, Deveci M, Coban S, Basar O, Yuksel O. A new cause of acute hepatitis: gemifloxacin. Acta Gastroenterol Belg. 2012 Dec;75(4):460-1.
43. Başar O, Yimaz B, Ekiz F, Giniş Z, Altinbaş A, Aktaş B, Tuna Y, Çoban S,Delibaş N, Yüksel O. Non-invasive tests in prediction of liver fibrosis in chronic hepatitis B and comparison with post-antiviral treatment results. Clin Res Hepatol Gastroenterol. 2013 Apr;37(2):152-8.
44. Karaahmet F, Basar Ö, Yüksel I, Coban S, Yuksel O. Letter: vitamin D supplementation and the irritable bowel syndrome. Aliment Pharmacol Ther. 2013 Feb;37(4):499.
45. Efe C, Ozaslan E, Wahlin S, Purnak T, Muratori L, Quarneti C, Yüksel O, Muratori P. Antibodies to soluble liver antigen in patients with various liver diseases: a multicentre study. Liver Int. 2013 Feb;33(2):190-6.
46. Karaahmet F, Coban S, Yuksel O, Başar O, Yüksel I. Letter: Clostridium difficile colitis in patients with ulcerative colitis. Aliment Pharmacol Ther. 2013 Jan;37(2):285-6.
47. Karaahmet F, Coban S, Başar O, Yuksel O. Letter: Vaptans for the treatment of hyponatraemia and ascites in patients with cirrhosis. Aliment Pharmacol Ther. 2012 Dec;36(11-12):1103-4; author reply 1104.
48. Köklü S, Tuna Y, Gülşen MT, Demir M, Köksal AŞ, Koçkar MC, Aygün C, Coban S, Ozdil K, Ataseven H, Akin E, Pürnak T, Yüksel I, Ataseven H, Ibiş M, Yildirim B, Nadir I, Küçükazman M, Akbal E, Yüksel O, Başar O, Alkan E, Baykal O. Long-term efficacy and safety of lamivudine, entecavir, and tenofovir for treatment of hepatitis B virus-related cirrhosis. Clin Gastroenterol Hepatol. 2013 Jan;11(1):88-94.
49. Kilincalp S, Deveci M, Basar O, Ekiz F, Coban S, Yuksel O.  Shark liver oil: hidden dangers. Ann Hepatol. 2012 Sep-Oct;11(5):728-30.
50. Karaahmet F, Kilincalp S, Deveci M, Coban S, Yuksel O. Letter: misoprostol may have a beneficial effect in biliary colic. Aliment Pharmacol Ther. 2012 Sep;36(6):602-3; author reply 603.
51. Coban Ş, Akbal E, Köklü S, Köklü G, Ulaşlı MA, Erkeç S, Aktaş B, Yüksel O,Koçak E, Erdem HR. Clinical trial: transcutaneous interferential electrical stimulation in individuals with irritable bowel syndrome - a prospective
52. double-blind randomized study. Digestion. 2012;86(2):86-93.
53. Aktaş B, Başar Ö, Altinbaş A, Ekiz F, Yüksel O. Rabeprazole-induced acute cholestatic liver injury. Turk J Gastroenterol. 2012 Jun;23(3):309-10.
54. Yüksel İ, Ekiz Ö, Ekiz F, Başar Ö, Yüksel O. Facial purpura in an elderly patient after upper gastrointestinal endoscopy. Chin Med J (Engl). 2012 Apr;125(8):1520.
55. Purnak T, Olmez S, Torun S, Efe C, Sayilir A, Ozaslan E, Tenlik I, Kalkan IH, Beyazit Y, Yuksel O. Mean platelet volume is increased in chronic hepatitis C patients with advanced fibrosis. Clin Res Hepatol Gastroenterol. 2012 May 7.
56. Altinbas A, Aktas B, Basar O, Yüksel O, Ekiz F, Yilmaz B, Coban S. Is there an association between the measurement of qualitative HBsAg and virologic response in chronic HBV infection? Ann Hepatol. 2012 May-Jun;11(3):320-5.
57. Ekiz F, Yuksel I, Simsek Z, Teber MA, Basar O, Altınbas A, Yüksel O. A foreign body in stomach: dental prosthesis. Acta Endosc. (2009) 39:437-438.
58. Dede F, Aylı D, Gonul I, Yuksel O, Ozturk R, Yıldız A, Yenigun E, Piskinpasa S, Turgut D, Koc E, Odabas AR. The Effect of Helicobacter Pylori Eradication on Proteinüria in Patients with Primary Glomerulonephritis. Archives of Medical Science. (Accept)
59. Efe C, Wahlin S, Ozaslan E, Berlot AH, Purnak T, Muratori L, Luigi QC, Yüksel O, Thiefin G, Muratori P. Autoimmune hepatitis/primary biliary cirrhosis overlap syndrome and associated extrahepatic autoimmune diseases. Eur J Gastroenterol Hepatol. 2012 May;24(5):531-4.
60. Yilmaz B, Coban S, Usküdar O, Unverdı H, Aktaş B, Yüksel O. Giant fibroepithelial polyp of the anus. Turk J Gastroenterol. 2011 Dec;22(6):651-2. PubMed PMID: 22287418
61. Karaahmet F, Kılıncalp S, Altınbas A, Coban S, Yuksel O. Intrabiliary rapamycin may slow progression of primary sclerosing cholangitis. Aliment Pharmacol Ther. 2012 Feb;35(4):490-1. doi: 10.1111/j.1365-2036.2011.04974.x. PubMed PMID: 22248428
62. Kılınçalp S, Ekiz F, Başar O, Coban S, Yüksel O. Equisetum arvense (Field Horsetail)-induced liver injury. Eur J Gastroenterol Hepatol. 2012 Feb;24(2):213-4. PubMed PMID: 22228296
63. Beyazit Y, Koklu S, Ozturk ZA, Yüksel O, Ibis M, Arhan M, Gultuna S, Sezer S, Yuksel I, Babali A. Inclusion of a Spasmolytic in Bowel Cleansing: A Prospective Randomized Study. Gastroenterol Nurs. 2011 Sep;34(5):352-355. PubMed PMID:21979395.
64. Ekiz F, Ormeci N, Coban S, Karabulut HG, Aktas B, Tukun A, Tuncali T, Yüksel O, Alkış N. Association of methylenetetrahydrofolate reductase C677T-A1298C polymorphisms with risk for esophageal adenocarcinoma, Barrett's esophagus, and reflux esophagitis. Dis Esophagus. 2011 Sep 23. doi:10.1111/j.1442-2050.2011.01262.x. [Epub ahead of print] PubMed PMID: 21951971.
65. Ekiz F, Yuksel O, Albayrak M, Çoban S, Albayrak A, Erarslan E. Ileocolonic involvement of follicular small cell lymphoma : A Rare Entity. Acta Gastro-Enterologica Belgica, Vol. LXXIV, October-December 2011
66. Yilmaz B, Ekız F, Coban S, Yüksel I, Yüksel O. Cefixime-induced hepatotoxicity. Turk J Gastroenterol. 2011 Aug;22(4):445. PubMed PMID: 21948584.
67. Altinbaş A, Sımşek Z, Usküdar O, Aktaş B, Yüksel O. Endoscopic removal of an ingested toothpick from the prepyloric antrum in an adult woman. Turk J Gastroenterol. 2011 Aug;22(4):439-40. PubMed PMID: 21948580.
68. Kılınçalp S, Altınbaş A, Başar O, Deveci M, Yüksel O. A case of ulcerative colitis co-existing with pseudo-membranous enterocolitis. J Crohns Colitis. 2011 Oct;5(5):506-7. Epub 2011 Aug 2. PubMed PMID: 21939932.
69. Altınbas A, Ekiz F, Yılmaz B, Basar O, Yuksel O. Dissolution of undigested food in a diabetic patient's stomach by drinking pineapple juice. Endocr Pract.2011 May-Jun;17(3):522-3. PubMed PMID: 21837823.
70. Ekız F, Yüksel O, Usküdar O, Yüksel I, Altinbaş A, Başar O. Successful endoscopic removal of fractured basket traction wire during mechanical lithotripsy. Turk J Gastroenterol. 2011 Apr;22(2):233-4. PubMed PMID: 21796572.
71. Purnak T, Efe C, Yuksel O, Beyazit Y, Ozaslan E, Altiparmak E. Mean platelet volume could be a promising biomarker to monitor dietary compliance in celiac disease. Ups J Med Sci. 2011 Aug;116(3):208-11. Epub 2011 Jun 16. PubMed PMID:21679011.
72. Ekiz F, Yüksel O, Koçak E, Yılmaz B, Altınbaş A, Çoban S, Yüksel I, Üsküdar O,Köklü S. Mean platelet volume as a fibrosis marker in patients with chronic hepatitis B. J Clin Lab Anal. 2011;25(3):162-5. doi:10.1002/jcla.20450. PubMed PMID: 21567462.
73. Yılmaz B, Yüksel O, Coban S, Cakmak I, Başar O, Ekiz F. Rare complication of ulcerative colitis: aseptic nasal septal abscess. Inflamm Bowel Dis. 2011 Jul;17(7):E71. doi: 10.1002/ibd.21732. Epub 2011 Apr 27. PubMed PMID: 21538715.
74. Ekiz F, Yüksel I, Ekiz O, Coban S, Basar O, Yüksel O. Levocetirizine induced hepatotoxicity in a patient with chronic urticaria. Ann Hepatol. 2011 Apr-Jun;10(2):237-8. PubMed PMID: 21502689.
75. Sımşek Z, Altinbaş A, Ekız F, Başar O, Yüksel I, Yüksel O. Cancer of the transverse colon revealed by a gastrocolic fistula. Turk J Gastroenterol. 2011 Feb;22(1):107-8. PubMed PMID: 21480126.
76. Simsek Z, Altinbas A, Yuksel I, Yuksel O. Effective treatment with pineapple juice in small bowel obstruction due to phytobezoar in a gastrectomized patient. Dig Endosc. 2011 Apr;23(2):197. doi:10.1111/j.1443-1661.2010.01059.x. PubMed PMID: 21429030.
77. Ekiz F, Usküdar O, Simsek Z, Yüksel I, Basar O, Altinbas A, Yüksel O. Cefuroxime axetil-induced liver failure. Ann Hepatol. 2010 Jul 1;9(3):306. PubMed PMID: 20720277.
78. Yilmaz B, Ekiz F, Yüksel I, Altinbas A, Deveci M, Yüksel O. A rare case of recurrent prolonged hepatotoxicity due to ornidazole. Ann Hepatol. 2010 Jul 1;9(3):305. PubMed PMID: 20720276.
79. Ekiz F, Yuksel I, Basar O, Coban S, Yuksel O, Teber MA. Liver injury associated with Malva grandifolia. Hepatobiliary Pancreat Dis Int. 2010 Aug;9(4):443-4. PubMed PMID: 20688614.
80. Altinbas A, Ekiz F, Yuksel O. Routine hepatitis B virus DNA testing in patients with human immunodeficiency virus. Hepatology. 2010 Jul;52(1):397. PubMed PMID: 20578159.
81. Ekiz F, Coban S, Onder EO, Turan D, Yuksel I, Yuksel O. A rare cause of dysphagia: esophageal hydatidosis. Gastrointest Endosc. 2010 Jun 9. [Epub ahead of print] PubMed PMID: 20538275.
82. Ekiz F, Yuksel I, Kertmen N, Yuksel O. Liver toxicity due to broccoli juice. Eur J Gastroenterol Hepatol. 2010 Jul;22(7):898. PubMed PMID: 20535075.
83. Altinbas A, Yüksel I, Pamukcu M, Ekiz F, Basar O, Yüksel O. Spontaneous HBsAg seroconversion after severe flare of chronic hepatitis B infection. Ann Hepatol. 2010 Apr-Jun;9(2):194-7. PubMed PMID: 20526016.
84. Altinbaş A, Coban S, Yüksel O. Fibrosis in liver as a predictive marker for hepatitis C virus therapy. Hepatology. 2010 May;51(5):1858; author reply 1858. PubMed PMID: 20432265.
85. Köklü S, Gültuna S, Yuksel O. Left-sided portal hypertension: 5-years follow-up. Hepatogastroenterology. 2010 Jan-Feb;57(97):1-2. PubMed PMID: 20422861.
86. Altinbas A, Ekiz F, Yuksel O. Obesity as risk factor for lactic acidosis during nucleoside analogue treatment. Hepatology. 2010 Jun;51(6):2235. PubMed PMID: 20229521.
87. Efe C, Nasirğlu N, Ozaslan E, Yuksel O, Tunca H, Sennaroglu E. Ascites and peritonitis due to leptospirosis. Eur J Gastroenterol Hepatol. 2010 Mar;22(3):376-7. PubMed PMID: 20134259.
88. Köklü S, Yüksel O, Onur I, Unverdi S, Biyikoğlu I, Akbal E, Sengül D, Unverdi H, Ekşioğlu M. Ileocolonic involvement in Behçet's disease: endoscopic and histological evaluation. Digestion. 2010;81(4):214-7. Epub 2010 Jan 21. PubMed PMID: 20110705.
89. Coban S, Ertugrul I, Ekiz F, Akif Teber M, Yuksel O. Budd-Chiari syndrome and portal vein thrombosis due to essential thrombocytosis. Platelets. 2010;21(2):144-6. PubMed PMID: 20085436.
90. Köklü S, Yuksel O, Coban S, Basar O. Is endoscopic band ligation necessary for primary prophylaxis of esophageal varices without high bleeding risks? Hepatology. 2009 Dec;50(6):2052; author reply 2052-3. PubMed PMID: 19937693.
91. Köklü S, Kekilli M, Arhan M, Demirel HA, Dadasov M, Yüksel O. A congenital anomaly as a cause of abdominal pain in a 74-year-old man. J Am Geriatr Soc. 2009 Sep;57(9):1728-9. PubMed PMID: 19895447.
92. Babalı A, Cakal E, Purnak T, Bıyıkoğlu I, Cakal B, Yüksel O, Köklü S. Serum alpha-fetoprotein levels in liver steatosis. Hepatol Int. 2009 Nov 5. [Epub ahead of print] PubMed PMID: 19890679; PubMed Central PMCID: PMC2790592.
93. Ataseven H, Oztürk ZA, Arhan M, Yüksel O, Köklü S, Ibiş M, Başar O, Yilmaz FM, Yüksel I. Cancer antigen 125 levels in inflammatory bowel diseases. J Clin Lab Anal. 2009;23(4):244-8. PubMed PMID: 19623645.
94. Odemiş B, Ciçek B, Zengin NI, Arhan M, Kacar S, Cengiz C, Yüksel O. Barrett's esophagus and endoscopically assessed esophagogastric junction integrity in 1000 consecutive Turkish patients undergoing endoscopy: a prospective study. Dis Esophagus. 2009;22(8):649-55. Epub 2009 Jun 9. PubMed PMID: 19515192.
95. Yüksel O, Köklü S, Başar O, Yüksel I, Akgül H. Erosive gastritis mimicking watermelon stomach. Am J Gastroenterol. 2009 Jun;104(6):1606-7. Epub 2009 Apr 21. PubMed PMID: 19491883.
96. Köklü S, Bulut M, Cakal B, Bozkurt A, Yüksel O. Gastric cancer presenting with Plummer-Vinson Syndrome. J Am Geriatr Soc. 2009 May;57(5):933-4. PubMed PMID: 19470022.
97. Yüksel O, Helvaci K, Başar O, Köklü S, Caner S, Helvaci N, Abayli E, Altiparmak E. An overlooked indicator of disease activity in ulcerative colitis: mean platelet volume. Platelets. 2009 Jun;20(4):277-81. PubMed PMID: 19459134.
98. Arhan M, Köklü S, Yalçin F, Batgi H, Yilmaz SR, Yüksel O. Severe intestinal bleeding in a patient with Wegener's granulomatosis. Am J Gastroenterol. 2009 Aug;104(8):2119-20. Epub 2009 May 19. PubMed PMID: 19455112.
99. Kisacik B, Akdogan A, Yilmaz G, Karadag O, Yilmaz FM, Koklu S, Yuksel O, Ertenli AI, Kiraz S. Serum adenosine deaminase activities during acute attacks and attack-free periods of familial Mediterranean fever. Eur J Intern Med. 2009 Jan;20(1):44-7. Epub 2008 Jun 20. PubMed PMID: 19237091.
100. Ibiş M, Yüksel O, Yilmaz G, Köklü S, Yilmaz FM, Ertuğrul I, Uçar E, Altiparmak ME. Serum angiotensin converting enzyme levels in pancreatic diseases. Hepatogastroenterology. 2008 Sep-Oct;55(86-87):1814-7. PubMed PMID: 19102399.
101. Ertuğrul I, Köklü S, Başar O, Yüksel O, Uçar E, Coban S, Ibiş M, Arhan M,Odemiş B, Saşmaz N. Thrombosis of the portal venous system: a prospective study. J Clin Gastroenterol. 2008 Aug;42(7):835-8. PubMed PMID: 18469722.
102. Oztürk ZA, Köklü S, Basat O, Yüksel O, Basar O, Filik L. Should We perform polypectomy for all colorectal polps, or follow-up. Chir Gastroenterol 2008;24:216-20.
103. Oztürk ZA, Köklü S, Erol MF, Yilmaz FM, Basar O, Yüksel O, Yilmaz G, Kisacik B, Yüksel I. Serum adenosine deaminase levels in diagnosis of acute appendicitis. Emerg Med J. 2008 Sep;25(9):583-5. PubMed PMID: 18723708.
104. Yüksel O, Bolat AD, Köklü S, Altiparmak E, Albayrak M, Caner S. Ischemic colitis, an unusual complication of colonoscopy. South Med J. 2008 Sep;101(9):972-3. PubMed PMID: 18708963.
105. Kayhan B, Ozer D, Akdogan M, Ozaslan E, Yuksel O. Can 5-aminosalicylic acid suppository decrease the pain after rectal band ligation? World J Gastroenterol. 2008 Jun 14;14(22):3523-5. PubMed PMID: 18567081; PubMed Central PMCID: PMC2716615.
106. Ertuğrul I, Köklü S, Başar O, Yüksel O, Uçar E, Coban S, Ibiş M, Arhan M,Odemiş B, Saşmaz N. Thrombosis of the portal venous system: a prospective study. J Clin Gastroenterol. 2008 Aug;42(7):835-8. PubMed PMID: 18469722.
107. Koşan B, Yüksel O, Ustün I, Köklü S, Topal F, Yilmaz M, Ergül B, Karaahmetoğlu S, Eskioğlu E, Altiparmak E. Role of endogenous cortisol on Helicobacter pylori colonization. Clin Biochem. 2008 Jul;41(10-11):917-9. Epub 2008 Mar 19. PubMed PMID: 18381206.
108. Yüksel O, Parlak E, Köklü S, Ertugrul I, Tunç B, Sahin B. Conscious sedation during endoscopic retrograde cholangiopancreatography: midazolam or midazolam plus meperidine? Eur J Gastroenterol Hepatol. 2007 Nov;19(11):1002-6. PubMed PMID: 18049171.
109. Ibiş M, Köklü S, Yilmaz FM, Başar O, Yilmaz G, Yüksel O, Yildirim E, Oztürk ZA. Serum adenosine deaminase levels in pancreatic diseases. Pancreatology. 2007;7(5-6):526-30. Epub 2007 Sep 27. PubMed PMID: 17901713.
110. Yolcu OF, Köklü S, Yüksel O, Coban S, Ayaz S, Akif Oztürk M, Benekli M. Vascular endothelial growth factor receptor-1 levels in hepatocellular carcinoma and correlations with clinicopathological features. Hepatogastroenterology. 2007 Jul-Aug;54(77):1526-8. PubMed PMID: 17708290.
111. Coban S, Yüksel O, Koçkar MC, Köklü S, Basar O, Tutkak H, Ormeci N. The significance of serum transforming growth factor beta 1 in detecting of gastric and colon cancers. Hepatogastroenterology. 2007 Jul-Aug;54(77):1472-6. PubMed PMID: 17708279.
112. Yüksel O, Arhan M, Köklü S, Oğuz P, Parlak E. Onerous concomitant complications of ulcerative colitis: a case report. Z Gastroenterol. 2007 May;45(5):379-81. PubMed PMID: 17503316.
113. Odemiş B, Parlak E, Başar O, Yüksel O, Sahin B. Biliary tract obstruction secondary to malignant lymphoma: experience at a referral center. Dig Dis Sci. 2007 Sep;52(9):2323-32. Epub 2007 Apr 4. PubMed PMID: 17406815.
114. Köklü S, Coban S, Yüksel O, Arhan M. Left-sided portal hypertension. Dig Dis Sci. 2007 May;52(5):1141-9. Epub 2007 Mar 24. Review. PubMed PMID: 17385040.
115. Arhan M, Köksal AŞ, Yüksel O, Akdoğan M. Karaciğer Fibrozisinin Değerlendirilmesinde Serum Hyaluronik Asit Düzeyinin Yeri Türkiye Klinikleri Tıp Bilimleri Dergisi 2007;27(1):21-26 (Dergi 2007 Ocak ayından itibaren SCI-Expanded kapsamında)
116. Savas N, Dagli U, Akbulut S, Yuksel O, Sahin B. Colorectal cancer localization in young patients: should we expand the screening program? Dig Dis Sci. 2007 Mar;52(3):798-802. PubMed PMID: 17245629.
117. Başar O, Oztürk MA, Köklü S, Ayaz S, Yüksel O, Kiraz S, Ertenli I, Calgüneri M. Plasma levels of soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) in familial Mediterranean fever. Joint Bone Spine. 2007 Jan;74(1):52-5. Epub 2006 Apr 17. PubMed PMID: 17223601.
118. Coban S, Ozkan H, Köklü S, Yüksel O, Koçkar MC, Akar T, Ormeci N. The utility of serum receptor-binding cancer antigen expressed on SiSo cells in gastrointestinal tract cancers. Can J Gastroenterol. 2006 Sep;20(9):593-6. PubMed PMID: 17001401; PubMed Central PMCID: PMC2659945.
119. Odemiş B, Köksal AS, Yüksel O, Kacar S, Turhan N. Squamous cell cancer of the liver arising from an epidermoid cyst: case report and review of the literature. Dig Dis Sci. 2006 Jul;51(7):1278-84. Review. PubMed PMID: 16944026.
120. Topal F, Ozaslan E, Akbulut S, Küçükazman M, Yüksel O, Altiparmak E. Methylprednisolone-induced toxic hepatitis. Ann Pharmacother. 2006 Oct;40(10):1868-71. Epub 2006 Aug 22. PubMed PMID: 16926305.
121. Odemis B, Ataseven H, Basar O, Ertugrul I, Yüksel O, Turhan N. Ulcer in the basis of Zenker's diverticulum mimicking esophageal malignancy. J Natl Med Assoc. 2006 Jul;98(7):1177-80.
122. Köklü S, Odemiş B, Cengiz C, Yüksel O, Usküdar O, Turhan N. Fulminant hepatic failure due to secondary amyloidosis. Dig Liver Dis. 2006 Mar;38(3):208-10. Epub 2006 Feb 7. PubMed PMID: 16461024.
123. Yüksel O, Köklü S, Arhan M, Yolcu OF, Ertuğrul I, Odemiş B, Altiparmak E, Sahin B. Effects of esophageal varice eradication on portal hypertensive gastropathy and fundal varices: a retrospective and comparative study. Dig Dis Sci. 2006 Jan;51(1):27-30. PubMed PMID: 16416205.
124. Köklü S, Parlak E, Yüksel O, Sahin B. Reply. Age Ageing. 2006 May;35(3):323; author reply.
125. Köklü S, Parlak E, Yüksel O, Sahin B. Endoscopic retrograde cholangiopancreatography in the elderly: a prospective and comparative study. Age Ageing. 2005 Nov;34(6):572-7. PubMed PMID: 16267181.
126. Altlparmak E, Koklu S, Yalinkilic M, Yuksel O, Cicek B, Kayacetin E, Sahin T. Viral and host causes of fatty liver in chronic hepatitis B. World J Gastroenterol. 2005 May 28;11(20):3056-9. PubMed PMID: 15918189.
127. Köklü S, Yüksel O, Arhan M, Coban S, Başar O, Yolcu OF, Uçar E, Ibiş M, Ertugrul I, Sahin B. Report of 24 left-sided portal hypertension cases: a single-center prospective cohort study. Dig Dis Sci. 2005 May;50(5):976-82.PubMed PMID: 15906778.
128. Köksal AS, Usküdar O, Köklü S, Yüksel O, Beyazit Y, Sahin B. Propranolol-exacerbated mesenteric ischemia in a patient with hyperthyroidism. Ann Pharmacother. 2005 Mar;39(3):559-62. Epub 2005 Feb 8. PubMed PMID: 15701768.
129. Köklü S, Oztürk MA, Balci M, Yüksel O, Ertenli I, Kiraz S. Interferon-gamma levels in familial Mediterranean fever. Joint Bone Spine. 2005 Jan;72(1):38-40. PubMed PMID: 15681246.
130. Coban S, Yüksel O, Köklü S, Ceyhan K, Baykara M, Dökmeci A. Atypical presentation of hepatocellular carcinoma: a mass on the left thoracic wall. BMC Cancer. 2004 Dec 1;4:89. PubMed PMID: 15574203; PubMed Central PMCID: PMC535896.
131. Yolcu OF, Köklü S, Köksal AS, Yüksel O, Beyazit Y, Basar O. Alfuzosin-induced acute hepatitis in a patient with chronic liver disease. Ann Pharmacother. 2004 Sep;38(9):1443-5. Epub 2004 Jul 27. PubMed PMID: 15280514.
132. Köklü S, Yüksel O, Yolcu OF, Arhan M, Altiparmak E. Cholestatic attack due to ampicillin and cross-reactivity to cefuroxime. Ann Pharmacother. 2004 Sep;38(9):1539-40. Epub 2004 Jul 20. PubMed PMID: 15266040.
133. Yüksel O, Köklü S, Uçar E, Saşmaz N, Sahin B. Severe recurrent gastrointestinal bleeding due to angiodysplasia in a Bernard-Soulier patient: an onerous medical concomitance. Dig Dis Sci. 2004 May;49(5):885-7. PubMed PMID: 15259515.
134. Köklü S, Yüksel O, Filik L, Usküdar O, Altundag K, Altiparmak E. Recurrent cholestasis due to ampicillin. Ann Pharmacother. 2003 Mar;37(3):395-7. PubMed PMID: 12639171.
135. Yüksel O, Dökmetaş HS, Topcu S, Erselcan T, Sencan M. Relationship between bone mineral density and insulin resistance in polycystic ovary syndrome. J Bone Miner Metab. 2001;19(4):257-62. PubMed PMID: 11448019.