广东中山肠胃检查多少钱(中山大便出很多血怎么回事) (今日更新中)

WASHINGTON, July 27 (Xinhua) -- Astronomers studying observations taken by NASA's Wide-field Infrared Survey Explorer (WISE) mission have discovered the first known "Trojan" asteroid orbiting the sun along with Earth, the U.S. National Aeronautics and Space Administration (NASA) announced Wednesday in a statement.Trojans are asteroids that share an orbit with a planet near stable points in front of or behind the planet. Because they constantly lead or follow in the same orbit as the planet, they never can collide with it. In our solar system, Trojans also share orbits with Neptune, Mars and Jupiter. Two of Saturn's moons share orbits with Trojans.Scientists had predicted Earth should have Trojans, but they have been difficult to find because they are relatively small and appear near the sun from Earth's point of view."These asteroids dwell mostly in the daylight, making them very hard to see," said Martin Connors of Athabasca University in Canada, lead author of a new paper on the discovery to be published Thursday in the journal Nature. "But we finally found one, because the object has an unusual orbit that takes it farther away from the sun than what is typical for Trojans. WISE was a game-changer, giving us a point of view difficult to have at Earth 's surface."The WISE telescope scanned the entire sky in infrared light from January 2010 to February 2011. Connors and his team began their search for an Earth Trojan using data from NEOWISE, an addition to the WISE mission that focused in part on near-Earth objects, or NEOs, such as asteroids and comets. NEOs are bodies that pass within 28 million miles (45 million kilometers) of Earth 's path around the sun. The NEOWISE project observed more than 155, 000 asteroids in the main belt between Mars and Jupiter, and more than 500 NEOs, discovering 132 that were previously unknown.The team's hunt resulted in two Trojan candidates. One called 2010 TK7 was confirmed as an Earth Trojan after follow-up observations with the Canada-France-Hawaii Telescope on Mauna Kea in Hawaii.The asteroid is roughly 1,000 feet (300 meters) in diameter. It has an unusual orbit that traces a complex motion near a stable point in the plane of Earth's orbit, although the asteroid also moves above and below the plane. The object is about 50 million miles (80 million kilometers) from Earth. The asteroid's orbit is well-defined and for at least the next 100 years, it will not come closer to Earth than 15 million miles (24 million kilometers).

COPENHAGEN, May 29 (Xinhua) -- The number of confirmed E.coli cases has risen to 11 with at least another eight persons suspected of having the intestinal infection in Denmark, according to Denmark's National Serum Institute on Sunday.Five of the confirmed cases show symptoms of kidney failure which marks an advanced stage of the sickness, the institute said.Danish cucumbers are suspected of helping spread the E. coli bacteria believed to be causing a deadly outbreak of intestinal infection in Denmark and Germany, local media reported Sunday.The Danish cucumbers were mixed in Germany with cucumbers originating in the Netherlands, making it difficult to determine if Danish cucumbers are in fact contaminated.Denmark's Veterinary and Food Administration (DVFA) had earlier said the suspicion against Danish cucumber was "vague", but advised Danish consumers not to eat raw tomatoes, lettuces and cucumbers from Germany, and cucumber from Spain.It is now checking Danish cucumbers for traces of E. coli with results expected on Tuesday.Some Danish retailers have now removed these products from their supermarket shelves. And the Danish branch of fast-food chain McDonald's announced Saturday that it was dropping fresh cucumbers from its menu until further notice.The infection, which is food-borne, can be caused by eating raw or uncooked foods such as vegetables contaminated with the E. coli bacteria.Symptoms of infection include mild fever, bloody diarrhea and vomiting, and can last five to seven days. It can prove fatal in the very young, sick, or elderly.

CANBERRA, June 6 (Xinhua) -- Australian beef is not to blame for a recent outbreak of E.coli in Japan, Meat and Livestock Australia confirmed on Monday.Twenty people have fallen ill in Japan's Toyama prefecture, with 15 of them infected with the O157 strain of E.coli after eating at a popular Korean-style barbecue restaurant chain, Gyukaka, on May 6.The operators of the restaurant chain, REINS International, said they suspected the bacterium might have been carried by beef imported from Australia.After conducting an investigation into the Japanese outbreak, regional manager for Meat and Livestock Australia, Melanie Brock, said testing shows Australian beef was not the source of the outbreak."The Toyama prefecture health authorities have confirmed following a thorough inspection that imported Australian beef was not the source of an incident of E.coli," Brock said in a statement on Monday."The authorities continue to investigate other food consumed by the affected customers."Brock said Australian beef has long been recognized by the Japanese trade and consumers for its strong safety record.Brock added that Australian beef for export to Japan is processed under the veterinary supervision of the Australian Quarantine and Inspection Service, and is recognized internationally as bearing a high hygienic standard.

BEIJING, August 1 (Xinhuanet) -- U.S. researchers have discovered a genetic mutation unique to African Americans that links to heighten their asthma risk, according to reports published on Sunday in the journal Nature Genetics.Researchers of University of Chicago found a gene, PYHIN1, and its variations may account for asthma risk in people of African descent. In their study, they examined data from nine previous genome-wide association studies, totaling more than 2 million single nucleotide polymorphisms in 3,246 asthma patients and 3,385 control patient, 1,702 patient-parent groupings, 355 family-based cases, and 468 family-based controls.In the study, the researchers found that between 26 percent and 29 percent of people of African-descent carried at least one copy of the gene.  In particular, one polymorphism of the gene was 34 percent more likely found in African-American and Afro-Caribbean people with asthma.  More interestingly, this variant of the gene is rarely found in Caucasian people and in Latino population, it was found in less than 5 percent.This new variant is part of a family of genes linked with the body's response to viral infections. It is thought to be involved in interferon signaling, which could influence the occurrence of asthma.The team stressed that each gene variant on its own plays only a small role in increasing asthma risk, but that risk could be multiplied when combined with other risk genes and with environmental factors.

WASHINGTON, Aug. 2 (Xinhua) -- The weakness of aging is associated with leaky calcium channels inside muscle cells and a drug already in Phase II clinical trials for the treatment of heart failure might plug those leaks, according to a report published Tuesday in the online edition of Cell Metabolism.Earlier studies by the research team led by Andrew Marks of Columbia University showed the same leaks underlie the weakness and fatigue that come with heart failure and Duchenne muscular dystrophy."It's interesting, normal people essentially acquire a form of muscular dystrophy with age," Marks said. "The basis for muscle weakness is the same." Extreme exercise like that done by marathon runners also springs the same sort of leaks, he added, but in that case damaged muscles return to normal after a few days of rest. A microscopic view shows smooth muscle cells derived from human embryonic stem cells showing the nuclei (blue) and proteins of the cytoskeleton (green) in this handout photo released to Reuters by the California Institute for Regenerative Medicine, March 9, 2009The leaks occur in a calcium release channel called ryanodine receptor 1 (RyR1) that is required for muscles to contract. Under conditions of stress, those channels are chemically modified and lose a stabilizing subunit known as calstabin1.Calcium inside of muscle cells is usually kept contained. When it is allowed to leak out into the cell that calcium itself is toxic, turning on an enzyme that chews up muscle cells. Once the leak starts, it's a vicious cycle. The calcium leak raises levels of damaging reactive oxygen species, which oxidize RyR1 and worsen the leak.The researchers made their discovery by studying the skeletal muscles of young and old mice. They also showed that 6-month-old mice carrying a mutation that made their RyR1 channels leaky showed the same muscular defects and weakness characteristic of older mice.When older mice were treated with a drug known as S107, the calcium leak in their muscles slowed and the animals voluntarily showed about a 50 percent increase in the amount of time spent wheel running. Now in clinical trials for patients with heart failure, the drug is known to work by restoring the connection between costabilin and RyR1.Despite considerable effort to understand and reverse age- related muscle wasting, there are no established treatments available. The new work suggests there may be hope in approaching the problem from a different angle."Most research has focused on making more muscle mass," Marks said. "What's different here is that we are focused not on muscle mass but on muscle function. More muscle doesn't help if it is not functional."

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