天津天津市龙济医院泌尿科(武清前列腺治疗选择天津市武清区龙济医院) (今日更新中)

WASHINGTON, Dec. 5 (Xinhua) -- NASA's Kepler mission has confirmed its first planet in the "habitable zone," a region where liquid water could exist on a planet's surface, the U.S. space agency announced on Monday.The newly-confirmed planet, Kepler-22b, is the smallest yet found to orbit in the middle of the habitable zone of a star similar to Sun. The planet is about 2.4 times the radius of Earth. Scientists don't yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding Earth-like planets.Previous research hinted at the existence of near-Earth-size planets in habitable zones, but clear confirmation proved elusive. Two other small planets orbiting stars smaller and cooler than Sun recently were confirmed on the very edges of the habitable zone, with orbits more closely resembling those of Venus and Mars.Kepler-22's star is a bit smaller than our sun, so its habitable zone is slightly closer in. The diagram shows an artist's rendering of the planet comfortably orbiting within the habitable zone, similar to where Earth circles the sun. Kepler-22b has a yearly orbit of 289 days. The planet is the smallest known to orbit in the middle of the habitable zone of a sun-like star. It's about 2.4 times the size of Earth."This is a major milestone on the road to finding Earth's twin, " said Douglas Hudgins, Kepler program scientist at the NASA Headquarters in Washington. "Kepler's results continue to demonstrate the importance of NASA's science missions, which aim to answer some of the biggest questions about our place in the universe."Kepler discovers planets and planet candidates by measuring dips in the brightness of more than 150,000 stars to search for planets that cross in front, or "transit," the stars. Kepler requires at least three transits to verify a signal as a planet."Fortune smiled upon us with the detection of this planet," said William Borucki, Kepler principal investigator at the NASA Ames Research Center who led the team that discovered Kepler-22b. "The first transit was captured just three days after we declared the spacecraft operationally ready. We witnessed the defining third transit over the 2010 holiday season."The Kepler science team uses ground-based telescopes and the Spitzer Space Telescope to review observations on planet candidates the spacecraft finds. The star field that Kepler observes in the constellations Cygnus and Lyra can only be seen from ground-based observatories in spring through early fall. The data from these other observations help determine which candidates can be validated as planets.Kepler-22b is located 600 light years away. While the planet is larger than Earth, its orbit of 290 days around a Sun-like star resembles that of Earth. The planet's host star belongs to the same class as Sun, called G-type, although it is slightly smaller and cooler.Of the 54 habitable-zone planet candidates reported in February 2011, Kepler-22b is the first to be confirmed. This finding will be published in The Astrophysical Journal.

RIO DE JANEIRO, Dec 15 (Xinhua) -- Brazilian President Dilma Rousseff Thursday signed a law banning smoking in public spaces and tobacco advertising at sale places in his country.Smoking in all enclosed public spaces, defined as free access areas used simultaneously by several people, is forbidden in the new law.It also prohibits tobacco advertising such as posters or banners at sale places. Previously the ban was only imposed on TV, radio and billboards advertising.In addition, the law increases the taxes and establishes minimum prices over the tobacco products to discourage buyers, therefore the cigarettes prices are expected to increase 20 percent in 2012 and 55 percent by 2015.Health warnings are also required on both sides of cigarette packs to alert consumers about the consequences of their smoking habit.The law is welcomed by some anti-smoking groups."In addition to protecting the health of its citizens, Brazil has also set an example for the world," said Matthew Myer, president of Campaign for Tobacco-Free Kids.

WASHINGTON, Oct. 13 (Xinhua) -- In a trial that included about 35,000 men, those who were randomized to receive daily supplementation with vitamin E had a significantly increased risk of prostate cancer, according to a study published this week in the Journal of the American Medical Association.The study followed more than 35,533 men 50 or older at 427 sites in the United States, Canada and Puerto Rico. The men were divided into four groups who took daily doses of 400 international units of Vitamin E and 200 micrograms of selenium; Vitamin E and a placebo that looked like selenium; selenium and a placebo that looked like Vitamin E; or two placebos. The recommended daily intake of Vitamin E is about 22.4 international units.The researchers from the Cleveland Clinic found that the rate of prostate cancer detection was greater in all treatment groups when compared with placebo but was statistically significant only in the vitamin E alone group -- a 17 percent increased rate of prostate cancer detection. The difference in rates of prostate cancer between vitamin E and placebo became apparent during the participants' third year in the trial. The elevated risk estimate for vitamin E was consistent across both low- and high-grade disease."The observed 17 percent increase in prostate cancer incidence demonstrates the potential for seemingly innocuous yet biologically active substances such as vitamins to cause harm. The lack of benefit from dietary supplementation with vitamin E or other agents with respect to preventing common health conditions and cancers or improving overall survival, and their potential harm, underscore the need for consumers to be skeptical of health claims for unregulated over-the-counter products in the absence of strong evidence of benefit demonstrated in clinical trials," the researchers said.

WASHINGTON, Oct. 3 (Xinhua) -- Researchers at St. Michael's Hospital in Canada have discovered a new function for an enzyme that may protect against organ injury and death from anemia, according to a study appearing Monday in the U.S. journal of the Proceeding of the National Academy of Sciences.Researchers found that when people have anemia, neuronal nitric oxide synthase (nNOS) -- an enzyme in nerve cells that produces nitric oxide, an important signaling molecule in the body -- increases the body's ability to respond, adapt to low oxygen levels and makes the body more efficient in delivering oxygen to tissues. They also found that levels of nNOS in the brain increased in anemic mice, and that the mice without this enzyme die earlier, and with higher hemoglobin levels."Identifying this mechanism may lead to new therapies and approaches to improving outcomes for anemic patients," said Dr. Greg Hare, a researcher at the Li Ka Shing Knowledge Institute of the hospital and one of the lead investigators of the study.Anemia occurs when blood has a lower than normal number of red blood cells or hemoglobin -- an iron-rich protein that carries oxygen from the lungs and heart to the rest of the body. Cells need oxygen to survive and to produce energy for all bodily functions. The condition has many different causes including infection (malaria, HIV, parasites), nutritional deficiencies (iron, folate, B12), genetic mutations, pregnancy, trauma and surgical blood loss."This research will help us identify when an anemic patient is at greatest risk for injury and death when undergoing surgery," said Hare. "Research is underway to test these findings in humans."

KUNMING, Nov. 30 (Xinhua) -- More than 10,000 new HIV infections were reported in southwest China's Yunnan province during the first 10 months of this year, bringing the total number of HIV carriers and AIDS patients in the province to more than 90,000, local AIDS prevention authorities said Wednesday.As of Oct. 31, a total of 93,567 HIV infections had been reported in the province, with the disease claiming 14,340 lives, according to statistics from the Yunnan AIDS Prevention Bureau.The number of HIV infections contracted through sexual contact has been rising and sexual contact is now the main cause of the disease's proliferation, said Xu Heping, director of the bureau.Of the province's infected population, 45.8 percent contracted the disease through sexual contact, while 37.3 percent contracted the disease through intravenous drug abuse, according to the bureau.Sexually transmitted infections accounted for 77.3 percent of new infections during the January-October period, up from 71.3 percent during the same period last year, according to the statistics.Xu said this year's new infections mainly occurred in people between the ages of 20 and 39, accounting for 60.8 percent of the total.Infections among rural residents and unemployed people accounted for 55.3 percent and 18.6 percent, respectively, of this year's total, according to Xu.Lu Lin, director of the Yunnan disease control and prevention center, said migrant workers are particularly vulnerable to the disease due to their nomadic nature and lack of knowledge about the disease.China currently has 346,000 registered HIV carriers and AIDS patients, although the actual number is predicted to hit 780,000 by the end of this year, according to an expert panel consisting of members of China's Ministry of Health (MOH), the World Health Organization and UNAIDS.

来源：资阳报