南宁微观解剖肌纤维模型(青海高级着装式老年行动模拟服) (今日更新中)

BEIJING, July 26 (Xinhuanet) -- Hong Kong scientists announced that they had determined the idea of time travel is impossible by proving nothing can travel faster than the speed of light.The finding is contained in a study done by a research team from Hong Kong University of Science and Technology. The study was published Monday in a scientific journal "Physical Review Letters" in the United States."The study, which showed that single photons also obey the speed limit c, confirms Einstein's causality, that is, an effect cannot occur before its cause," the university said on its website."By showing that single photons cannot travel faster than the speed of light, our results bring a closure to the debate on the true speed of information carried by a single photon." said Professor Du Shengwang, who led the study.The possibility of time travel was raised 10 years ago when scientists discovered the optical pulses in some specific medium might propagate information in a faster-than-light speed."Our findings will also likely have potential applications by giving scientists a better picture on the transmission of quantum information." Du said.

BEIJING, Sep. 13 (Xinhuanet) --Experts have called for a national drug-control system after a nationwide deficit of a life-saving drug, which has lasted at least three months.Doctors at a Beijing hospital said some specialized hospitals, which perform hundreds of cardiac operations every month, have been paralyzed by their lack of protamine sulfate, which is commonly administered after heart surgery to reverse the anticoagulant effects of heparin.The earliest report of a shortage was in Hubei province on July 21. This was followed by reports of shortages in Guangdong, Shandong and Liaoning provinces.The Shandong newspaper, Qilu Evening News, quoted a regional sales manager, surnamed Zhuang, as saying the province had been allocated 150 doses of protamine sulfate after Shanghai No 1 Biochemical and Pharmaceutical Co Ltd recently resumed production of the drug."But its monthly use here is usually 10,000 doses," he said.The Ministry of Health has denied it is responsible for supplies of the drug and passed the buck to the State Food and Drug Administration, claiming the latter is responsible for the supervision of medicines.Shen Chen, head of the publicity office of the State Food and Drug Administration, said he was unaware of the shortage, but said the administration is responsible for the quality of medicines, not the supply."Development and reform authorities oversee the medicines' prices, while the industrial and commercial authorities oversee the storage. The food and drug departments only cover the approval and quality of medicines."Industry insiders said one of the reasons for the shortage was the low profit margin, which discourages companies from mass producing the drug."Some companies can't earn enough to recover their costs, therefore it is almost impossible to maintain their enthusiasm for continuing production," said Lu Guoping, secretary-general of the Shanghai Pharmaceutical Trade Association.Lu said the government should issue policies to prevent future shortages of such medicines to avoid possible nationwide public health incidents.Yi Shenghua, a lawyer at Beijing Yingke Law Firm, said the country should have a unified system to guarantee the normal supply of medicines that are widely used and drug manufacturers should fulfill their responsibilities to society, even though there is no law stipulating they should produce specific medicines.He came up with two ways to deal with the problem of companies only producing profitable drugs."The government can order businesses to manufacture a certain amount of cheap medicines. Or it can offer financial assistance to subsidize cheap, but life-saving medicines."

THE HAGUE, June 24 (Xinhua) -- Bird flu was discovered at a poultry farm in the central Dutch province of Flevoland, the Ministry of Agriculture said Friday.It said the virus discovered was a mild variant. The farm's 47,000 chickens were slaughtered to prevent the virus turning into a contagious and deadly variant.It remains uncertain whether the chickens were infected with the high or low pathologene H7 variant. The low pathologene version can mutate into a high pathologen, which is extremely transmittable.Poultry from other farms in a zone of three kilometres of the contaminated farm will be tested. A prohibition of transport for poultry, eggs and poultry manure has been set.

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.

BEIJING, July 13 (Xinhuanet) -- Gasoline powers vehicles all around the world, but a sick Chinese man has been drinking the sticky liquid for 42 years under the illusion that it can relieve his physical pain.Chen Dejun, 71, lives by himself in shabby thatched cottage on a hill in Shuijiang township, Nanchuan district of southwest China's Chongqing municipality. The short and bony man said he drinks 3 to 3.5 kilograms of gasoline every month, which he buys from a station at the foot of the hill.Chen is known locally as a stonecutter and master of weaving bamboo with a good business sense. But he’s also known for his undying love of drinking gasoline.He developed the habit back in 1969 when he suddenly began coughing and felt pain in his chest. Seeing no progress after trying some medicine, he took up the folk remedy of drinking kerosene, Chongqing Evening News reported.It turned out to be helpful for him after the first sip, and he since became addicted to kerosene. Then he moved on to gasoline.Chen said it is hard to calculate exactly how much gasoline he has swallowed throughout his life, but the newspaper reported Chen has consumed an estimated 1.5 tons over the past 42 years.Chen's wife Yuan Huibi and their three sons tried many times to stop Chen's addiction to gasoline, but those efforts only made the family relations tense. Eight years ago Chen moved to the cottage to live alone.Sources from Honglou Hospital in Chongqing said Chen‘s health is fine despite having symptoms of emphysema. Chen refused to receive free check ups from the hospital.Feng Fu, an associate professor with the Second Hospital Affiliated to Chongqing Medical University, said Chen may have developed some resistance to gasoline. Otherwise, Feng said, it would be impossible for Chen to live. Feng also said gasoline may only work as anaesthetic for Chen but can’t cure his pain.

来源：资阳报