山东痛风是什么症况(山东尿酸降下来多久后不痛) (今日更新中)

CANBERRA, Aug. 17 (Xinhua) -- Australian scientist on Wednesday said his international research team has discovered the trick on how butterfly learn to change its wing pattern to avoid being eaten by birds.The Amazonian butterfly, Heliconius numata, has learnt to carry out a single genetic switch to alter its wing pattern so it appears to be another bad-tasting butterfly that birds will avoid.Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at Australia's University of Melbourne was part of the international research team, which was led by scientists at Centre National de la Recherche Scientifique (CNRS) and the University of Exeter in United Kingdom.Dr. Lee said the historical mystery had puzzled researchers for decades."Charles Darwin was puzzled by how butterflies evolved such similar patterns of warning coloration," Dr. Siu Fai (Ronald) Lee from the Department of Genetics and Bio21 Institute at the University of Melbourne told Western Australia Today."We have now solved this mystery, identifying the region of chromosome responsible for changing wing pattern."He said the research team identified a genetic switch known as a supergene, which allowed the butterfly to morph into several different forms, allowing one species to mimic another."It is amazing that by changing just one small region of the chromosomes, the butterfly is able to fool its predators by mimicking a range of different butterflies that taste bad," he said."The butterflies rearrange this supergene DNA like a small pack of cards, and the result is new wing patterns. It means that butterflies look completely different but have the same DNA."There are other butterflies doing similar tricks, but this is the most elegant one."I was just fascinated by how elegant they were."He said the discovery proves that small chromosomal changes can preserve successful gene combinations, and thus help a species to adapt.The findings of the study are published on August 14 in the international journal Nature.

MOSCOW, Aug. 7 (Xinhua) -- A state of emergency has been imposed in a district in the Krasnodar Region in south Russia amid an out break of the African swine fever, the regional emergencies center said on Sunday.The emergencies center told local reporters that the African swine fever virus (ASFV) was found in a private farm where 15 pigs died of the disease, but the source of the infection is still unclear.Local authorities said some 12,000 pigs in and around the Krylovskaya village, some three km away from the private farm, are being culled, 50 of which have already died of the ASFV in recent days.In April, the regional emergencies has temporarily declared a state of emergency in the Labinsky district in the region, as the ASFV was found at a livestock farm. 85 pigs were culled at the farm.

WASHINGTON, July 5 (Xinhua) -- Adhering to a healthy lifestyle, including not smoking, exercising regularly, having a low body weight and eating a healthy diet, appears to lower the risk of sudden cardiac death (SCD) in women, according to a study to be published Wednesday in the Journal of the American Medical Association."Sudden cardiac death (defined as death occurring within one hour after symptom onset without evidence of circulatory collapse) accounts for more than half of all cardiac deaths, with an incidence of approximately 250,000 to 310,000 cases annually in the United States," the authors write as background information in the study.Using data collected as part of the Nurses' Health Study, Stephanie Chiuve, of Brigham and Women's Hospital and Harvard Medical School, and colleagues examined the association between a healthy lifestyle and risk of SCD.A total of 81,722 women who participated in the Nurses' Health Study from June 1984 to June 2010 were included in the new study, and lifestyle factors were assessed via questionnaires every two to four years. A low-risk lifestyle was defined as not smoking, having a body mass index (BMI) of less than 25, exercise duration of 30 minutes/day or longer, and consuming a diet closely related to a Mediterranean-style diet (emphasizes high intake of vegetables, fruits, nuts, legumes, whole grains and fish, with moderate alcohol intake).During the 26 years of follow-up, there were 321 cases of SCD among women (average age 72 years at the time of the SCD event) in the study. All four low-risk factors were significantly and independently associated with a lower risk of SCD. Not smoking, exercising and eating a healthy diet each were inversely associated with risk of SCD. BMI also was associated with the risk of SCD, with women having a BMI between 21 and 24.9 at lowest risk.Women at low risk for all four lifestyle factors had a 92 percent lower risk of SCD when compared with women at low risk for none of the four lifestyle factors."In this cohort of female nurses, adherence to an overall healthy lifestyle was associated with a lower risk of SCD and may be an effective strategy for the prevention of SCD," the authors write.

CHENGDU, Sept. 3 (Xinhua) -- A list of this year's top 500 Chinese enterprises was unveiled in the city of Chengdu in southwest China's Sichuan Province on Saturday.The Sinopec Group was ranked first, with last year's revenues reaching 1.97 trillion yuan (307.81 billion U.S. dollars), followed by the China National Petroleum Corp. and State Grid Corp., whose revenues hit 1.72 trillion yuan and 1.53 trillion yuan last year, respectively.The rest of the top 10 was rounded out by the Industrial and Commercial Bank of China, China Mobile, China Railway Group, China Railway Construction Corp., China Construction Bank, China Life Insurance Co. and Agricultural Bank of China.The list is the 10th of its kind to be jointly released by the China Enterprise Confederation and the China Enterprise Directors Association. The threshold for entering the list was raised to 14.2 billion yuan in revenues, an increase over the 11.08-billion-yuan threshold used during the previous year.Revenues for China's top 500 companies rose 31.6 percent year-on-year to 36.31 trillion yuan in 2010, while their total assets increased by 18.4 percent to 108.1 trillion yuan, the two organizations said.The companies reported profits of 2.08 trillion yuan for last year, a rise of 38.67 percent from one year earlier.They paid 2.73 trillion yuan in taxes in 2010, accounting for 37.3 percent of the country's total tax revenues.

PARIS, Aug. 7 (Xinhua) -- European heavy-lift launcher Ariane 5 lifted off two communication satellites on Saturday.The Ariane 5, carrying Astra 1N and BSAT-3c/JCSAT-110R, was launched at 2252 GMT on Saturday from Kourou launch centre in French Guiana, according to live broadcast of the launching process.This was the fourth mission of Ariane 5 in 2011 and its 203th flight that sent off the two satellites Saturday night to their respective geostationary transfer orbits.Astra 1N, to be separated first, is built by EADS Astrium in Toulouse, France, for the Luxembourg-based operator SES Astra. With a designed lifespan of 15 years, it has an estimated liftoff mass of 5,350 kg and is fitted with 52 active Ku-band transponders.It is initially to deliver interim capacity from an orbital position of 28.2 degree East, and will subsequently move to SES Astra's prime location at 19.2 degree East for primary and backup services.BSAT-3c/JCSAT-110R is manufactured by Lockheed Martin Commercial Space Systems in Newtown, Pennsylvania, for Japanese operators B-SAT Corporation and SKY Perfect JSAT Corporation. This satellite weighs approximately 2,910 kg at launch time. It is to be positioned at 110 degree East longitude in geostationary orbit with a lifetime exceeding 16 years.This Ariane 5 flight has been postponed twice, firstly due to some technical problem in early July and then delayed by bad weather.Arianespace plans to achieve six Ariane 5 missions through this year.

来源：资阳报