CARACAS, Venezuela (AP) _ Cuban doctor Vivian Iglesias hears gunfire at night while trying to sleep. She's seen two murder victims, and someone ripped a gold chain off her neck two days after she arrived in April.

For her willingness to brave Caracas' Resplandor slum, Iglesias has earned the admiration of her patients in this hamlet of tin shacks stacked atop one another. Many here are getting personal medical attention for the first time.

Iglesias is one of 1,000 Cuban doctors working and living in Caracas slums under a program sponsored by President Hugo Chavez. In exchange, Venezuela is providing Cuba with oil.

``We never thought we'd get a doctor around these parts,'' says Yanis Narvaez, 26, holding her feverish toddler inside her leaky shanty while Iglesias took his temperature. ``I don't think she is doing anything bad like a lot of people say just because she is Cuban.''

Critics say the ``Inside the Barrio'' program is proof that Chavez wants to impose a communist system like that of his friend and mentor, Cuban President Fidel Castro.

Venezuela's opposition claims the doctors, along with more than 1,000 Cuban sports trainers and teachers here, have a socialist political agenda. Chavez's open admiration for Castro in a country that once defeated a Cuban-backed insurgency fuels the criticism.

But Chavez and his supporters insist ``Inside the Barrio'' and other Cuban-backed programs are key to achieving a balance between socialism and the free market policies he claims have impoverished Latin America.

``It's not a question of the worth and ability of the Cuban sports trainers, medical doctors and teachers because it's useless to deny the benefits of their presence,'' wrote Teodoro Petkoff, a former guerrilla who is editor of Tal Cual newspaper.

``Chavez, by creating the image that he is marching toward a society modeled after Fidel's Cuba, has created strong resistance to his government.''

Chavez's government has sent more than 4,000 needy Venezuelans to Cuba for free medical treatment. Cuban teachers are training 100,000 Venezuelan volunteers for a national literacy campaign.

Venezuela, meanwhile, provides Cuba with crude oil.

Cuba long has sent medical brigades to other developing nations. It recently agreed to send 80 doctors and nurses to Trinidad and Tobago.

But the Venezuelan Medical Federation says the Cubans are taking jobs needed by 8,000 unemployed local physicians. The federation also complains the Cubans haven't taken equivalency classes and exams normally required for foreign doctors to practice in Venezuela.

At the Jose Gregorio Hernandez public hospital in western Caracas, doctors like Henry Prato fume at government suggestions that they don't make similar sacrifices to serve the poor.

A pediatrician, Prato earns $325 a month _ half what it costs to feed and house a family of five. He and fellow doctors didn't get their state Christmas bonuses last year. The nine-story hospital's elevators don't work. Its bathrooms don't either.

Elsewhere, state doctors and nurses work double shifts to make ends meet. Shortages of medicines and bandages are common.

``In Venezuela, there are many doctors who are much more prepared ... who know the treatments used here, know what medicines are used here and know the diseases in Venezuela,'' Prato said.

With one doctor for every 500 people, there's no shortage, but many slum or rural residents can't quickly get medical care, said Fernando Bianco, president of the Caracas Metropolitan District College of Doctors.

Bianco and government officials insist Venezuelans eventually will replace Cubans in the program.

The Cubans live with host families and work in clinics tucked in the maze of hillside shanties ringing Caracas. The goal is to provide basic health care for about 1 million people.

The Cubans receive a $250 monthly stipend.

The Cubans are needed now, Bianco says, because most Venezuelan doctors fear living in slums.

In Iglesias' clinic, there is no evidence of a political agenda, such as portraits of Castro on walls or lectures about the Cuban system. The only portrait is of Chavez, and a slogan painted at the entrance says, ``'Inside the Slum' is the revolution advancing with the strength of the people.''

``I really never imagined things would be like this,'' Iglesias says. ``Robberies, muggings. ... But I like the Venezuelans. I like how they talk, their sayings, and if I can help, that's great.''