List of works - Takayuki Yamamoto

>0 g, ≤5 g A multicenter retrospective study aiming to identify patients who respond well to adsorptive granulomonocytapheresis in moderately to severely active ulcerative colitis.

scientific article

A meta-analysis comparing conventional end-to-end anastomosis vs. other anastomotic configurations after resection in Crohn's disease

scientific article published on 01 October 2007

A new anastomotic technique for prevention of postoperative recurrence in Crohn's disease

scientific article published on 21 November 2012

A novel sol particle immunoassay for fecal calprotectin in inflammatory bowel disease patients.

scientific article

Adacolumn leucocytapheresis for ulcerative colitis: clinical and endoscopic features of responders and unresponders

scientific article

Adalimumab and postoperative complications of elective intestinal resections in Crohn's disease: a propensity score case-matched study.

scientific article

Adalimumab for the prevention of recurrence after surgery for Crohn's disease

scientific article published on 01 July 2012

Adalimumab or infliximab for the prevention or treatment of post-operative recurrence in Crohn's disease

scientific article published on 27 September 2012

An Increased Serum N-Terminal Telopeptide of Type I Collagen, a Biochemical Marker of Increased Bone Resorption, Is Associated with Infliximab Therapy in Patients with Crohn's Disease

scientific article published on 08 August 2015

An intestinal fistula in a 3-year-old child caused by the ingestion of magnets: Report of a case ⬇️

scientific article published on 01 January 1995

An open-label prospective randomized multicenter study of intensive versus weekly granulocyte and monocyte apheresis in active crohn's disease

scientific article published on 19 November 2015

Anti-TNF and Postoperative Complications in Abdominal Crohn's Disease Surgery

scientific article published in January 2019

Anti-inflammatory effects of enteral nutrition on mesentery fat in patients with Crohn's disease

scientific article published on 04 December 2014

Biologics and surgical outcomes in Crohn's disease: is there a direct relationship?

scientific article published on 16 July 2020

Can Fecal Biomarkers Detect Ileal Inflammation in Inflammatory Bowel Disease?

scientific article

Changes in the rate of and trends in colectomy for ulcerative colitis during the era of biologics and calcineurin inhibitors based on a Japanese nationwide cohort study

scientific article published on 15 July 2019

Comment to 'Nutritional therapy versus 6-mercaptopurine as maintenance therapy in patients with Crohn's disease'

scientific article published on 14 September 2012

Comparison of Safety and Efficacy of Tacrolimus versus Infliximab for Active Ulcerative Colitis.

scientific article published on 19 October 2017

Consecutive Monitoring of Fecal Calprotectin and Lactoferrin for the Early Diagnosis and Prediction of Pouchitis after Restorative Proctocolectomy for Ulcerative Colitis.

scientific article

Consecutive monitoring of faecal calprotectin during mesalazine suppository therapy for active rectal inflammation in ulcerative colitis.

scientific article

Conventional vs nonconventional strictureplasties for Crohn's disease

scientific article published on 01 November 2012

Correction: A multicenter retrospective study aiming to identify patients who respond well to adsorptive granulomonocytapheresis in moderately to severely active ulcerative colitis

scientific article published on 08 October 2018

Correction: A multicenter retrospective study aiming to identify patients who respond well to adsorptive granulomonocytapheresis in moderately to severely active ulcerative colitis

scientific article published on 14 November 2018

Diagnosis and monitoring of postoperative recurrence in Crohn's disease

scientific article published on 17 July 2014

Dietary and enteral interventions for Crohn's disease.

scientific article

Direct retrospective comparison of adalimumab and infliximab in preventing early postoperative endoscopic recurrence after ileocaecal resection for crohn's disease: results from the MULTIPER database

scientific article published on 28 March 2015

Disappointing results following proctectomy with end-colostomy for anorectal Crohn's disease

scientific article published on 07 September 2012

Does preoperative enteral nutrition reduce the incidence of surgical complications in patients with Crohn's disease? A case-matched study

scientific article published on 29 November 2019

Editorial: tacrolimus vs. anti-tumour necrosis factor agents for moderately to severely active ulcerative colitis--authors' reply.

scientific article

Effects of preoperative leukocytapheresis on inflammatory cytokines following surgery for ulcerative colitis: a prospective randomized study

scientific article published on 3 September 2013

Efficacy of biologic therapy in patients with chronic pouchitis.

scientific article published on 9 August 2012

Efficacy of enteral nutrition during infliximab maintenance therapy in patients with Crohn's disease.

scientific article published on 30 November 2012

Efficacy of granulocyte and monocyte apheresis for antibiotic-refractory pouchitis after proctocolectomy for ulcerative colitis: an open-label, prospective, multicentre study.

scientific article

Elemental diet therapy for pouchitis following restorative proctocolectomy for ulcerative colitis

scientific article published on 13 September 2012

Endoscopic score vs. fecal biomarkers for predicting relapse in patients with ulcerative colitis after clinical remission and mucosal healing.

scientific article

Enteral nutrition for maintaining remission in patients with quiescent Crohn's disease: current status and future perspectives

scientific article published on 15 August 2015

Enteral nutrition for the maintenance of remission in Crohn's disease: a systematic review.

scientific article published on January 2010

Factors affecting recurrence after surgery for Crohn's disease.

scientific article published in July 2005

Factors affecting the incidence of early endoscopic recurrence after ileocolonic resection for Crohn's disease: a multicentre observational study

scientific article published on 10 December 2016

Faecal biomarkers for screening small bowel inflammation in patients with Crohn's disease: a prospective study.

scientific article published on 4 July 2017

Faecal calprotectin and lactoferrin as markers for monitoring disease activity and predicting clinical recurrence in patients with Crohn's disease after ileocolonic resection: A prospective pilot study.

scientific article

Faecal calprotectin level for assessing endoscopic activity and predicting future clinical course in patients with moderately active ulcerative colitis undergoing granulomonocytapheresis: a prospective cohort study

scientific article published on 01 August 2018

Fecal calprotectin and lactoferrin as predictors of relapse in patients with quiescent ulcerative colitis during maintenance therapy.

scientific article

Fecal calprotectin for detection of postoperative endoscopic recurrence in Crohn's disease: systematic review and meta-analysis

scientific article published on 08 July 2018

Fistula-associated anal carcinoma in Crohn's disease

scientific article published on 24 July 2018

Follow up of more than 10 years after strictureplasty for jejunoileal Crohn's disease: long-term results and predictive factors for outcome

scientific article published on 01 March 1999

Granulocyte and monocyte adsorptive apheresis in the treatment of active distal ulcerative colitis: a prospective, pilot study.

scientific article published on October 2004

Granulomonocytapheresis as a cell-dependent treatment option for patients with inflammatory bowel disease: Concepts and clinical features for better therapeutic outcomes

scientific article published on 08 November 2018

Impact of Preoperative Nutritional Status on the Incidence Rate of Surgical Complications in Patients With Inflammatory Bowel Disease With Vs Without Preoperative Biologic Therapy: A Case-Control Study

scientific article published on 01 June 2019

Impact of elemental diet on mucosal inflammation in patients with active Crohn's disease: cytokine production and endoscopic and histological findings

scientific article published on 01 June 2005

Impact of long-term enteral nutrition on clinical and endoscopic recurrence after resection for Crohn's disease: A prospective, non-randomized, parallel, controlled study

scientific article published on 01 January 2007

Impact of selective leukocytapheresis on mucosal inflammation and ulcerative colitis: cytokine profiles and endoscopic findings

scientific article published on 01 August 2006

Impacts of long-term enteral nutrition on clinical and endoscopic disease activities and mucosal cytokines during remission in patients with Crohn's disease: a prospective study

scientific article published on 01 December 2007

Increases in body mass index during infliximab therapy in patients with Crohn's disease: an open label prospective study

scientific article published on 04 August 2011

Infliximab for early endoscopic recurrence in patients with Crohn's disease

scientific article published on 24 March 2012

Infliximab for the prevention of postoperative recurrence in patients with multiple surgeries for Crohn's disease

scientific article published on 17 March 2012

Intraperitoneal cytokine productions and their relationship to peritoneal sepsis and systemic inflammatory markers in patients with inflammatory bowel disease

scientific article published on 01 May 2005

Is fecal calprotectin useful for monitoring endoscopic disease activity in patients with postoperative Crohn's disease?

scientific article published on 30 August 2013

Is pouch surgery safe in children with ulcerative colitis who are treated with preoperative immunosuppressive medications?

scientific article

Jejunal Crohn's disease is associated with a higher postoperative recurrence rate than ileocaecal Crohn's disease

scientific article published on 01 July 2005

Letter: The effects of preoperative infliximab on complications after surgery for ulcerative colitis

scientific article published on 01 December 2012

Letter: can a specific surgical approach reduce post-operative recurrence in Crohn's disease?

scientific article published on 01 November 2018

Letter: deleterious effects of smoking on post-operative Crohn's disease.

scientific article published in June 2016

Letter: diet and relapse in Crohn's disease

scientific article published on 01 March 2014

Letter: endoscopic balloon dilatation or strictureplasty for stricturing Crohn's disease?

scientific article published on 01 August 2012

Letter: endoscopic monitoring and treatment step-up in post-operative Crohn's disease

scientific article published on 01 May 2012

Letter: faecal calprotectin and lactoferrin - accurate biomarkers in post-operative Crohn's disease?

scientific article published on 01 August 2014

Letter: faecal calprotectin for the prediction of relapse in inactive inflammatory bowel disease.

scientific article

Letter: faecal diversion for severe perianal Crohn's disease - practical issues

scientific article published on 01 November 2015

Letter: is measurement of faecal biomarkers helpful for the early diagnosis and prediction of pouchitis after proctocolectomy for ulcerative colitis?

scientific article published on 01 January 2020

Letter: leucocytapheresis as a nonpharmacologic treatment for patients with ulcerative colitis during pregnancy

scientific article published on 01 January 2015

Letter: pre-operative anti-TNF-α and post-operative complications in ulcerative colitis

scientific article published on 01 July 2012

Letter: should we delay surgery, or stop anti-TNF therapy prior to elective surgical procedures in Crohn's disease patients receiving anti-TNF agents?

scientific article published on 01 October 2019

Letter: small bowel recurrence and fate of the rectum after total colectomy and ileostomy for Crohn's colitis

scientific article published in March 2017

Letter: which patient profile for tacrolimus in ulcerative colitis? Authors' reply

scientific article published on 01 June 2016

Letter: wide variation in faecal calprotectin values according to the assay - authors' reply.

scientific article

Long Time from Diagnosis to Surgery May Increase Postoperative Complication Rates in Elective CD Intestinal Resections: An Observational Study.

scientific article

Long strictureplasty is as safe and effective as short strictureplasty in small-bowel Crohn's disease

scientific article published on 01 November 2004

Long-term clinical impact of early introduction of granulocyte and monocyte adsorptive apheresis in new onset, moderately active, extensive ulcerative colitis.

scientific article published on 12 January 2012

Long-term efficacy of enteral nutrition for patients with Crohn's disease

scientific article published on 21 October 2012

Long-term results of strictureplasty without synchronous resection for jejunoileal Crohn's disease

scientific article published in February 1999

Modern management of perianal fistulas in Crohn's disease: future directions.

scientific article published on 13 January 2018

Monitoring and detection of disease recurrence after resection for Crohn's disease: the role of non-invasive fecal biomarkers

scientific article

Mucosal healing in patients with ulcerative colitis during a course of selective leukocytapheresis therapy: a prospective cohort study.

scientific article

Mucosal inflammation in the terminal ileum of ulcerative colitis patients: endoscopic findings and cytokine profiles

scientific article published on 19 February 2008

Nutrition and diet in inflammatory bowel disease.

scientific article

POSTOPERATIVE APPROACH FOR CROHN'S DISEASE: THE RIGHT THERAPY TO THE RIGHT PATIENT.

scientific article

Peritoneal cytokines as early markers of peritonitis following surgery for colorectal carcinoma: A prospective study ⬇️

scientific article published on November 12, 2010

Postoperative change of mucosal inflammation at strictureplasty segment in Crohn's disease: cytokine production and endoscopic and histologic findings

scientific article published on 01 April 2005

Postoperative infliximab and elemental diet combination in a case with diffuse, extensive jejunoileal Crohn's disease.

scientific article published on 23 October 2013

Preoperative Vedolizumab and Postoperative Outcomes in Inflammatory Bowel Disease: Does Smoke Always Mean Fire?

scientific article

Prevention of Postoperative Recurrence in CD: Tailoring Treatment to Patient Profile

scientific article published on 01 January 2019

Prevention of postoperative recurrence in Crohn's disease

scientific article published on 01 March 2014

Prevention of recurrence after surgery for Crohn’s disease: Efficacy of infliximab ⬇️

scientific article published on November 21, 2010

Real life results in using 5-ASA for maintaining mild to moderate UC patients in Japan, a multi-center study, OPTIMUM Study.

scientific article

Reply to Lee and Brown

scientific article published on 24 January 2020

Review article: diet and inflammatory bowel disease--epidemiology and treatment.

scientific article

Risk factors for anastomotic complications after resection for Crohn's disease

scientific article published on 01 October 2012

Risk factors for complications after ileocolonic resection for Crohn's disease with a major focus on the impact of preoperative immunosuppressive and biologic therapy: A retrospective international multicentre study

scientific article published on 06 August 2015

Risk factors for pouchitis after surgery for ulcerative colitis.

scientific article published in June 2013

Risk factors for symptomatic recurrence after intestinal resection for Crohn's disease: a retrospective study in a Chinese population.

scientific article published on 23 April 2013

Safety and efficacy of strictureplasty for Crohn's disease: a systematic review and meta-analysis.

scientific article published on November 2007

Serial monitoring of faecal calprotectin for the assessment of endoscopic recurrence in asymptomatic patients after ileocolonic resection for Crohn's disease: a long-term prospective study.

scientific article published on May 2016

Steroid-sparing strategies in the management of ulcerative colitis: efficacy of leukocytapheresis.

scientific article published on November 2012

Strictureplasty or resection for small-bowel Crohn's disease?

scientific article published on 01 December 2012

Strictureplasty vs resection in small bowel Crohn's disease: an evaluation of short-term outcomes and recurrence

scientific article published on 01 October 2007

Surgery for luminal Crohn's disease.

scientific article published on January 2014

Systemic and local cytokine production in quiescent ulcerative colitis and its relationship to future relapse: a prospective pilot study.

scientific article

Tacrolimus vs. anti-tumour necrosis factor agents for moderately to severely active ulcerative colitis: a retrospective observational study

scientific article published on 13 January 2016

The clinical value of faecal calprotectin and lactoferrin measurement in postoperative Crohn's disease.

scientific article published on February 2015

The effect of smoking after surgery for Crohn's disease: a meta-analysis of observational studies.

scientific article published on 2 September 2008

The impact of early endoscopic lesions on the clinical course of patients following ileocolonic resection for Crohn's disease: A 5-year prospective cohort study

scientific article published in August 2013

The impact of preoperative biologic therapy on anastomotic complications after surgery for Crohn's disease

scientific article published on 19 July 2012

The impact of preoperative infliximab therapy on postoperative complications in patients with ulcerative colitis

scientific article published on 27 June 2012

The impact of preoperative total parenteral nutrition on early complications after surgery for Crohn's disease

scientific article published on 16 May 2012

The impact of preoperative use of infliximab on postoperative complications in patients with Crohn's disease

scientific article published on 02 July 2012

The impact of the fecal stream and stasis on immunologic reactions in ileal pouch after restorative proctocolectomy for ulcerative colitis: a prospective, pilot study.

scientific article

The risk of postoperative complications following preoperative anti-TNF therapy in patients with Crohn's disease: the need for prospective studies.

scientific article published on 18 April 2013

The role of granulocyte and monocyte apheresis in inflammatory bowel disease

scientific article published on 03 August 2012

The role of strictureplasty in the surgical management of duodenal Crohn's disease

scientific article published on 20 December 2012

The value of plasma cytokine measurement for the detection of strangulation in patients with bowel obstruction: a prospective, pilot study

scientific article published on 01 July 2005

Therapeutic strategies for prevention of postoperative recurrence in patients with Crohn's disease

scientific article published on 01 December 2012

Treating inflammatory bowel disease by adsorptive leucocytapheresis: a desire to treat without drugs

scientific article

Treatment options for children and adolescents with inflammatory bowel disease: is granulomonocytapheresis an effective alternative to drug therapy?

scientific article published on 14 June 2017

List of works by Takayuki Yamamoto

>0 g, ≤5 g A multicenter retrospective study aiming to identify patients who respond well to adsorptive granulomonocytapheresis in moderately to severely active ulcerative colitis.

A meta-analysis comparing conventional end-to-end anastomosis vs. other anastomotic configurations after resection in Crohn's disease

A new anastomotic technique for prevention of postoperative recurrence in Crohn's disease

A novel sol particle immunoassay for fecal calprotectin in inflammatory bowel disease patients.

Adacolumn leucocytapheresis for ulcerative colitis: clinical and endoscopic features of responders and unresponders

Adalimumab and postoperative complications of elective intestinal resections in Crohn's disease: a propensity score case-matched study.

Adalimumab for the prevention of recurrence after surgery for Crohn's disease

Adalimumab or infliximab for the prevention or treatment of post-operative recurrence in Crohn's disease

An Increased Serum N-Terminal Telopeptide of Type I Collagen, a Biochemical Marker of Increased Bone Resorption, Is Associated with Infliximab Therapy in Patients with Crohn's Disease

An intestinal fistula in a 3-year-old child caused by the ingestion of magnets: Report of a case ⬇️

An open-label prospective randomized multicenter study of intensive versus weekly granulocyte and monocyte apheresis in active crohn's disease

Anti-TNF and Postoperative Complications in Abdominal Crohn's Disease Surgery

Anti-inflammatory effects of enteral nutrition on mesentery fat in patients with Crohn's disease

Biologics and surgical outcomes in Crohn's disease: is there a direct relationship?

Can Fecal Biomarkers Detect Ileal Inflammation in Inflammatory Bowel Disease?

Changes in the rate of and trends in colectomy for ulcerative colitis during the era of biologics and calcineurin inhibitors based on a Japanese nationwide cohort study

Comment to 'Nutritional therapy versus 6-mercaptopurine as maintenance therapy in patients with Crohn's disease'

Comparison of Safety and Efficacy of Tacrolimus versus Infliximab for Active Ulcerative Colitis.

Consecutive Monitoring of Fecal Calprotectin and Lactoferrin for the Early Diagnosis and Prediction of Pouchitis after Restorative Proctocolectomy for Ulcerative Colitis.

Consecutive monitoring of faecal calprotectin during mesalazine suppository therapy for active rectal inflammation in ulcerative colitis.

Conventional vs nonconventional strictureplasties for Crohn's disease

Correction: A multicenter retrospective study aiming to identify patients who respond well to adsorptive granulomonocytapheresis in moderately to severely active ulcerative colitis

Correction: A multicenter retrospective study aiming to identify patients who respond well to adsorptive granulomonocytapheresis in moderately to severely active ulcerative colitis

Diagnosis and monitoring of postoperative recurrence in Crohn's disease

Dietary and enteral interventions for Crohn's disease.

Direct retrospective comparison of adalimumab and infliximab in preventing early postoperative endoscopic recurrence after ileocaecal resection for crohn's disease: results from the MULTIPER database

Disappointing results following proctectomy with end-colostomy for anorectal Crohn's disease

Does preoperative enteral nutrition reduce the incidence of surgical complications in patients with Crohn's disease? A case-matched study

Editorial: tacrolimus vs. anti-tumour necrosis factor agents for moderately to severely active ulcerative colitis--authors' reply.

Effects of preoperative leukocytapheresis on inflammatory cytokines following surgery for ulcerative colitis: a prospective randomized study

Efficacy of biologic therapy in patients with chronic pouchitis.

Efficacy of enteral nutrition during infliximab maintenance therapy in patients with Crohn's disease.

Efficacy of granulocyte and monocyte apheresis for antibiotic-refractory pouchitis after proctocolectomy for ulcerative colitis: an open-label, prospective, multicentre study.

Elemental diet therapy for pouchitis following restorative proctocolectomy for ulcerative colitis

Endoscopic score vs. fecal biomarkers for predicting relapse in patients with ulcerative colitis after clinical remission and mucosal healing.

Enteral nutrition for maintaining remission in patients with quiescent Crohn's disease: current status and future perspectives

Enteral nutrition for the maintenance of remission in Crohn's disease: a systematic review.

Factors affecting recurrence after surgery for Crohn's disease.

Factors affecting the incidence of early endoscopic recurrence after ileocolonic resection for Crohn's disease: a multicentre observational study

Faecal biomarkers for screening small bowel inflammation in patients with Crohn's disease: a prospective study.

Faecal calprotectin and lactoferrin as markers for monitoring disease activity and predicting clinical recurrence in patients with Crohn's disease after ileocolonic resection: A prospective pilot study.

Faecal calprotectin level for assessing endoscopic activity and predicting future clinical course in patients with moderately active ulcerative colitis undergoing granulomonocytapheresis: a prospective cohort study

Fecal calprotectin and lactoferrin as predictors of relapse in patients with quiescent ulcerative colitis during maintenance therapy.

Fecal calprotectin for detection of postoperative endoscopic recurrence in Crohn's disease: systematic review and meta-analysis

Fistula-associated anal carcinoma in Crohn's disease

Follow up of more than 10 years after strictureplasty for jejunoileal Crohn's disease: long-term results and predictive factors for outcome

Granulocyte and monocyte adsorptive apheresis in the treatment of active distal ulcerative colitis: a prospective, pilot study.

Granulomonocytapheresis as a cell-dependent treatment option for patients with inflammatory bowel disease: Concepts and clinical features for better therapeutic outcomes

Impact of Preoperative Nutritional Status on the Incidence Rate of Surgical Complications in Patients With Inflammatory Bowel Disease With Vs Without Preoperative Biologic Therapy: A Case-Control Study

Impact of elemental diet on mucosal inflammation in patients with active Crohn's disease: cytokine production and endoscopic and histological findings

Impact of long-term enteral nutrition on clinical and endoscopic recurrence after resection for Crohn's disease: A prospective, non-randomized, parallel, controlled study

Impact of selective leukocytapheresis on mucosal inflammation and ulcerative colitis: cytokine profiles and endoscopic findings

Impacts of long-term enteral nutrition on clinical and endoscopic disease activities and mucosal cytokines during remission in patients with Crohn's disease: a prospective study

Increases in body mass index during infliximab therapy in patients with Crohn's disease: an open label prospective study

Infliximab for early endoscopic recurrence in patients with Crohn's disease

Infliximab for the prevention of postoperative recurrence in patients with multiple surgeries for Crohn's disease

Intraperitoneal cytokine productions and their relationship to peritoneal sepsis and systemic inflammatory markers in patients with inflammatory bowel disease

Is fecal calprotectin useful for monitoring endoscopic disease activity in patients with postoperative Crohn's disease?

Is pouch surgery safe in children with ulcerative colitis who are treated with preoperative immunosuppressive medications?

Jejunal Crohn's disease is associated with a higher postoperative recurrence rate than ileocaecal Crohn's disease

Letter: The effects of preoperative infliximab on complications after surgery for ulcerative colitis

Letter: can a specific surgical approach reduce post-operative recurrence in Crohn's disease?

Letter: deleterious effects of smoking on post-operative Crohn's disease.

Letter: diet and relapse in Crohn's disease

Letter: endoscopic balloon dilatation or strictureplasty for stricturing Crohn's disease?

Letter: endoscopic monitoring and treatment step-up in post-operative Crohn's disease

Letter: faecal calprotectin and lactoferrin - accurate biomarkers in post-operative Crohn's disease?

Letter: faecal calprotectin for the prediction of relapse in inactive inflammatory bowel disease.

Letter: faecal diversion for severe perianal Crohn's disease - practical issues

Letter: is measurement of faecal biomarkers helpful for the early diagnosis and prediction of pouchitis after proctocolectomy for ulcerative colitis?

Letter: leucocytapheresis as a nonpharmacologic treatment for patients with ulcerative colitis during pregnancy

Letter: pre-operative anti-TNF-α and post-operative complications in ulcerative colitis

Letter: should we delay surgery, or stop anti-TNF therapy prior to elective surgical procedures in Crohn's disease patients receiving anti-TNF agents?

Letter: small bowel recurrence and fate of the rectum after total colectomy and ileostomy for Crohn's colitis

Letter: which patient profile for tacrolimus in ulcerative colitis? Authors' reply

Letter: wide variation in faecal calprotectin values according to the assay - authors' reply.

Long Time from Diagnosis to Surgery May Increase Postoperative Complication Rates in Elective CD Intestinal Resections: An Observational Study.

Long strictureplasty is as safe and effective as short strictureplasty in small-bowel Crohn's disease

Long-term clinical impact of early introduction of granulocyte and monocyte adsorptive apheresis in new onset, moderately active, extensive ulcerative colitis.