吉林最权威的男性医院(吉林无痛包皮要多少钱) (今日更新中)

WASHINGTON, July 20 (Xinhua) -- The loss of a protein that coats sperm may explain a significant proportion of infertility in men worldwide, according to a study by an international team of researchers led by University of California Davis.A paper describing the work was published Wednesday in the journal Science Translational Medicine. The research could open up new ways to screen and treat couples for infertility.The gene DEFB126 encodes a protein called Beta Defensin 126, which coats the surface of sperm and helps it penetrate cervical mucus in the female. A survey of samples from the U.S., Britain and China showed that as many as a quarter of men worldwide carry two copies of the defective gene.In the new study, researchers found that men with a muted DEFB126 lack Beta Defensin 126, making it much more difficult for sperm to swim through the mucus and eventually join with an egg.Examining 500 newly married Chinese couples, researchers found that the lack of Beta Defensin 126 in men with the DEFB126 mutation lowered fertility (even among men that did not display other deficiencies usually associated with infertility, like inadequate semen volume and low sperm motility). Wives of men with the Beta Defensin 126 variant were significantly less likely to become pregnant than were other couples, and 30 percent less likely to have a birth.This genetic variation in DEFB126 likely accounts for many unexplained cases of infertility, researchers say. They hope next to work with a major infertility program in the U.S. to further explore the role of the mutation.

GENEVA, Aug. 12 (Xinhua) -- 18 people seeking treatment at hospitals in Somalia had been confirmed cholera positive through laboratory tests, the Geneva based World Health Organization (WHO) said on Friday.The 18 positive cases were detected out of 30 stool samples collected from patients seeking treatment at hospitals for acute watery diarrhea, a symptom that could result from cholera, WHO spokesperson Tarek Jasarevic told reporters.All confirmed cases, including residents of Mogadishu district and those among internally displaced persons (IDPs), were said to be tested positive for the Vibrio cholera serotype "inaba", which had been the predominant serotype in Somalia for the past three years."These results are an alarming reminder of the critical situation in Mogadishu and other parts of Southern, Central Somalia, (which are) still experiencing drought, population displacement and conflict," Jasarevic said.WHO has reported a dramatic increase of acute watery diarrhea cases in Somalia.In June and July alone, 1,633 acute watery diarrhea cases had been registered in Banadir Hospital, Mogadishu, representing 38 percent of all reported cases in 2011, and a sharp rise comparing with the same period last year.The United Nations public health arm said the situation was related to poor sanitation and limited access to safe water in numerous informal IDP settlements and a limited capacity of existing health partners to access those settlements and provide essential health services.In addition, the high number of malnourished children due to the ongoing famine increased the susceptibility to waterborne diseases.

STOCKHOLM, Aug. 30 (Xinhua) -- Meat diet, a dietary habit popular in some developed countries, can produce more greenhouse gas and thus is likely to actually cause more impact on climate, said a Swedish study published Tuesday.According to Swedish Radio's Ekot news program, the meat diet, also known as Low Carb High Fat (LCHF) diet, doubled the greenhouse gas emission compared with the balanced diet recommended by the Swedish Food Administration.Many Swedish people have abandoned the diet habit of eating root vegetables and fruits, and switched to LCHF diets. The LCHF diet has more meat, fat and unusual greenhouse gas emission. But these root vegetables, such as potatoes and carrots, and other naturally grown vegetables can be planted with less greenhouse gas emission.The report also revealed that many of the LCHF diet advices are actually given by the researchers sponsored by meat industry.

LOS ANGELES, July 22 (Xinhua) -- Two teams of astronomers have discovered the largest and farthest reservoir of water ever detected in the universe, NASA's Jet Propulsion Laboratory (JPL) said on Friday.The water, equivalent to 140 trillion times all the water in the world's ocean, surrounds a huge, feeding black hole, called a quasar, more than 12 billion light-years away, according to JPL in Pasadena, California."The environment around this quasar is very unique in that it's producing this huge mass of water," said Matt Bradford, a scientist at JPL. "It's another demonstration that water is pervasive throughout the universe, even at the very earliest times. "This artist's concept illustrates a quasar, or feeding black hole, similar to APM 08279+5255, where astronomers discovered huge amounts of water vapor. Gas and dust likely form a torus around the central black hole, with clouds of charged gas above and below. X-rays emerge from the very central region, while thermal infrared radiation is emitted by dust throughout most of the torus. While this figure shows the quasar's torus approximately edge-on, the torus around APM 08279+5255 is likely positioned face-on from our point of view.A quasar is powered by an enormous black hole that steadily consumes a surrounding disk of gas and dust. As it eats, the quasar spews out huge amounts of energy. Both groups of astronomers studied a particular quasar called APM 08279+5255, which harbors a black hole 20 billion times more massive than the sun and produces as much energy as a thousand trillion suns.Astronomers expected water vapor to be present even in the early, distant universe, but had not detected it this far away before. There's water vapor in the Milky Way, although the total amount is 4,000 times less than in the quasar, because most of the Milky Way's water is frozen in ice. Water vapor is an important trace gas that reveals the nature of the quasar. In this particular quasar, the water vapor is distributed around the black hole in a gaseous region spanning hundreds of light-years in size (a light-year is about six trillion miles).Its presence indicates that the quasar is bathing the gas in X- rays and infrared radiation, and that the gas is unusually warm and dense by astronomical standards, JPL said.Although the gas is at a chilly minus 63 degrees Fahrenheit ( minus 53 degrees Celsius) and is 300 trillion times less dense than Earth's atmosphere, it's still five times hotter and 10 to 100 times denser than what's typical in galaxies like the Milky Way, said JPL.Measurements of the water vapor and of other molecules, such as carbon monoxide, suggest there is enough gas to feed the black hole until it grows to about six times its size, JPL said.Whether this will happen is not clear, the astronomers say, since some of the gas may end up condensing into stars or might be ejected from the quasar.Bradford's team made their observations starting in 2008, using an instrument called "Z-Spec" at the California Institute of Technology's (Caltech's) Submillimeter Observatory, a 33-foot (10- meter) telescope near the summit of Mauna Kea in Hawaii. Follow-up observations were made with the Combined Array for Research in Millimeter-Wave Astronomy (CARMA), an array of radio dishes in the Inyo Mountains of Southern California.The second group, led by Dariusz Lis, senior research associate in physics at Caltech and deputy director of the Caltech Submillimeter Observatory, used the Plateau de Bure Interferometer in the French Alps to find water. In 2010, Lis's team serendipitously detected water in APM 8279+5255, observing one spectral signature.Bradford's team was able to get more information about the water, including its enormous mass, because they detected several spectral signatures of the water, according to JPL.

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