Publications by authors named "Rafael F Perini"

In carcinogenesis, the "field defect" is recognized clinically because of the high propensity of survivors of certain cancers to develop other malignancies of the same tissue type, often in a nearby location. Such field defects have been indicated in colon cancer. The molecular abnormalities that are responsible for a field defect in the colon should be detectable at high frequency in the histologically normal tissue surrounding a colonic adenocarcinoma or surrounding an adenoma with advanced neoplasia (well on the way to a colon cancer), but at low frequency in the colonic mucosa from patients without colonic neoplasia.

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Portal hypertensive gastropathy (PHG) is often seen in patients with portal hypertension, and can lead to transfusion-dependent anemia as well as acute, life-threatening bleeding episodes. This Review focuses on the mechanisms that underlie the pathogenesis of PHG that provide reasonable grounds for the treatment of this condition, and ultimately enable translation of basic research into clinical practice. Increased portal pressure associated with cirrhosis and liver dysfunction is critical for the development of clinically significant PHG, and leads to impaired gastric mucosal defense mechanisms that render the stomach susceptible to mucosal injury.

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Purpose: Laparoscopic cholecystectomy (LC) is the treatment of choice for gallstones. There is an increased incidence of bile duct injuries in LC compared with the open technique. Isolated right segmental hepatic duct injury (IRSHDI) represents a challenge not only for management but also for diagnosis.

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Background: Bleeding as a complication of endoscopic sphincterotomy is influenced by several factors. The objective of this study was to compare rates of bleeding after sphincterotomy performed with two different electrosurgical current generators (Valleylab SSE2L and ERBE ICC200).

Methods: A total of 6179 consecutive reports of ERCP were analyzed to compare the frequency of endoscopically and clinically evident bleeding after sphincterotomy when using the Valleylab SSE2L generator (from February 1994 to November 1997) and the ERBE ICC200 generator (from December 1997 to September 2000).

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The healing of gastric ulcer is a complicated process that involves the proliferation of epithelial and endothelial cells and the concerted actions of a wide range of growth factors. Prostaglandins play an important role in ulcer healing. Expression of cyclooxygenase-2 (COX-2) is markedly upregulated around the margins of gastric ulcers and its inhibition leads to a delay of ulcer healing.

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