The condition of veteran Marxist leader and former West Bengal Chief Minister Jyoti Basu slightly improved on Wenesday. According to Medical bulletin some positive changes of his health has been found. <br/> <br/>Spokesman of the nursing home told reporters in Kolkata that his blood pressure is under control and urinary output has shown improvement. But, Mr.Basu is still critical and has been kept on ventilation. He was admitted in a private nursing home on first January following attack of pneumonia. <br/> <br/>AIR correspondent reports that political leaders cutting across party lines visited the nursing home on Wednesday to enquire about his health. <br/> <br/>The Prime Minister, Dr. Manmohan Singh is visiting Kolkata today to see the ailing Marxist leader. CPI(M) General Secretary Prakash Karat and Polit Bureau member Sitaram Yechury are also arriving in the city today to see the veteran leader. <br/><br/>