昆明市医院流产(昆明如果打胎要多久) (今日更新中)

WASHINGTON, Jan. 2 (Xinhua) -- A systematic review of previous studies suggests that there may be a positive connection between physical activity and children's academic performance, according to a report published Monday in the Archives of Pediatrics & Adolescent Medicine.A group of scientists at the Vrije Universiteit (Free University) Medical Center in the Netherlands reviewed evidence on the relationship between physical activity and academic performance because of concerns that pressure to improve test scores may often mean more instructional time for classroom subjects with less time for physical activity.The authors identified 10 observational and four interventional studies for review, 12 of which were done in the United States, one in Canada and one in South Africa. Sample sizes ranged from 53 to about 12,000 participants between the ages of eight years and 18 years old. Follow-up varied from eight weeks to more than five years."According to the best-evidence synthesis, we found strong evidence of a significant positive relationship between physical activity and academic performance. The findings of one high-quality intervention study and one high-quality observational study suggest that being more physically active is positively related to improved academic performance in children," the report said.Background information in the article suggests that exercise may help cognition by increasing blood and oxygen flow to the brain, increasing levels of norepinephrine and endorphin to decrease stress and improve mood, and increasing growth factors that help create new nerve cells and support synaptic plasticity."More high-quality studies are needed on the dose-response relationship between physical activity and academic performance and on the explanatory mechanisms, using reliable and valid measurement instruments to assess this relationship accurately," the report concluded.

COPENHAGEN, Oct. 1 (Xinhua) -- Denmark implemented a tax on foods high in saturated fat from Saturday, the first of its kind in the world, which will affect products containing more than 2.3 percent saturated fat.Butter, cream, cheese, meat, cooking oil and processed foods like pizza and dark chocolate are among thousands of products affected. The so-called fat tax is pegged at 16 Danish kroner (2.87 U.S. dollars) per kilo of saturated fat.Thus, a 250-gram packet of butter, which previously cost 15.5 Danish kroner (2.78 dollars), will now cost 18.10 Danish kroner (3.25 dollars). And the cost of a liter of olive oil has risen from 38.95 Danish kroner (7 dollars) to 41.60 Danish kroner (7.48 dollars), for example.Some Danes began hoarding the affected products ahead of Saturday's deadline, while stores across Denmark rushed to mark-up prices of these goods.Although the new tax will mean higher costs for consumers and many food product manufacturers, the Danish government believes the tax is a good way of reducing Danes'consumption of fatty foods.Local producers are worried the tax will give an unfair advantage to manufacturers from neighboring countries who, they say, can now sell their products more cheaply in the Danish market.However, tax authorities here said imported food products will also be subject to the tax.

BEIJING, Jan. 14 (Xinhua) -- A Spring Festival gala was held at the Great Hall of the People Saturday to entertain the country's military officers, soldiers and civilians.Representatives of officers and soldiers in the military units and armed police forces in Beijing as well as some Beijing residents attended the gala.President Hu Jintao and other top Chinese leaders including Wu Bangguo, Jia Qinglin, Li Changchun, Xi Jinping, Li Keqiang, He Guoqiang and Zhou Yongkang were also present at the gala.Hu expressed greetings to the audience and extended his good wishes for them, ahead of the traditional Spring Festival, or the Chinese Lunar New Year, which falls on Jan. 23 this year.

NEW YORK, Dec. 1 (Xinhua) -- New York City Mayor Michael Bloomberg announced on Thursday a new recommendation that doctors offer every person with an HIV diagnosis antiretroviral treatment to help them live longer and prevent transmission.This marks a change from the current practice that treatment only be offered to those who show signs of damage to their immune systems, said the mayor during the annual World AIDS Day commemorative ceremony at Gracie Mansion. "Over the past ten years HIV diagnoses and deaths in New York City have seen a dramatic decline," said Mayor Bloomberg. "Steady progress in our fight against HIV has turned what used to be a death sentence into a disease that can be prevented and, with antiretroviral therapy, managed.The annual death toll from HIV in the city is down by more than a third: 933 deaths in 2009Despite this progress, however, more than 110,000 people in New York City are infected with HIV, more than in any other U.S. city and about 75 percent of all cases in the New York State.Figures from the New York City Health and Hospitals Corporation (HHC) showed that HHC has tested more than one million New Yorkers for HIV since 2005 when the public hospitals and health centers began offering HIV screening as a routine part of medical care for patients aged 13 to 64.

来源：资阳报