The bull is a graph consisting of a triangle and two vertex-disjoint pendant edges. A graph is called bull-free if no induced subgraph of it is a bull. A graph G is perfect if for every induced subgraph H of G, the chromatic number of H equals the size of the largest complete subgraph of H. This paper describes the structure of all bull-free perfect graphs.

The bull is a graph consisting of a triangle and two pendant edges. A graph is called bull-free if no induced subgraph of it is a bull. This is a summary of the last two papers [2, 3] in a series [1, 2, 3]. The goal of the series is to give a complete description of all bull-free graphs. We call a bull-free graph elementary if it does not contain an induced three-edge-path P such that some vert...

the gastric cancer in iran is the fourth in the general population. this study was designed to determine the five-year survival rate of gastric cancer patients, and to assess its associated factors. we analyzed the data using a time-dependent covariates model, and recommend it for analyses of similar data. 281 gastric cancer patients with adenocarcinomatous pathology who had been operated on at...

Background & Aims: Gastric carcinoma is the second most frequent cancer worldwide. Adjuvant treatment of gastric cancer varies worldwide; many differences have been observed in their clinical and pathological features, and survival rate. The aim of this study was to determine clinical and pathological features, and survival rate in a group of patients in south-east of Iran. Methods: Patient rec...

Aim: The experiment was conducted to study the total seminal plasma protein (TSPP) and heparin-binding proteins (HBPs) in relation to initial semen quality of buffalo bull. Materials and Methods: Semen from two Murrah buffalo bulls (bull no. 605 and 790) with mass motility of ≥3+ were used for the study and categorized into three groups (Group IMass motility 3+, Group IIMass motility 4+ and Gro...